Boeing 737 - 600/700/800/900. Flight Crew Training Manual (1999 year)

Maneuvers

Recovery from a Fully Developed Stall

An airplane may be stalled in any attitude (nose high, nose low, high angle of

bank) or any airspeed (turning, accelerated stall). It is not always intuitively

obvious that the airplane is stalled.

An airplane stall is characterized by any one (or a combination) of the following

conditions:

• buffeting, which could be heavy

• lack of pitch authority

• lack of roll control

• inability to arrest descent rate.

These conditions are usually accompanied by a continuous stall warning. A stall

must not be confused with the stall warning that alerts the pilot to an approaching

stall. Recovery from an approach to a stall is not the same as recovery from an

actual stall. An approach to a stall is a controlled flight maneuver; a stall is an

out-of-control, but recoverable, condition.

Note: Anytime the airplane enters a fully developed stall, the autopilot and

autothrottle should be disconnected.

To recover from a stall, angle of attack must be reduced below the stalling angle.

Nose down pitch control must be applied and maintained until the wings are

unstalled. Application of forward control column (as much as full forward may be

required) and the use of some nose-down stabilizer trim should provide sufficient

elevator control to produce a nose-down pitch rate. It may be difficult to know

how much stabilizer trim to use, and care must be taken to avoid using too much

trim. Pilots should not fly the airplane using stabilizer trim, and should stop

trimming nose down when they feel the g force on the airplane lessen or the

required elevator force lessen.

Under certain conditions, on airplanes with underwing-mounted engines, it may

be necessary to reduce thrust in order to prevent the angle of attack from

continuing to increase. Once the wing is unstalled, upset recovery actions may be

taken and thrust reapplied as needed.

If normal pitch control inputs do not stop an increasing pitch rate in a nose high

situation, rolling the airplane to a bank angle that starts the nose down may be

effective. Bank angles of about 45°, up to a maximum of 60°, could be needed.

Normal roll controls - up to full deflection of ailerons and spoilers - may be used.

Unloading the wing by maintaining continuous nose-down elevator pressure

keeps the wing angle of attack as low as possible, making the normal roll controls

as effective as possible.

7.20

Maneuvers

Finally, if normal pitch control then roll control is ineffective, careful rudder input

in the direction of the desired roll may be required to initiate a rolling maneuver

recovery.

WARNING: Only a small amount of rudder is needed. Too much rudder

applied too quickly or held too long may result in loss of lateral

and directional control.

Steep Turns

The objective of the steep turn maneuver is to familiarize the pilot with airplane

handling characteristics beyond 35° of bank and improve the instrument cross

check. During training, 45° of bank is used for this maneuver. It is not intended

that the pilot should ever be required to bank greater than 25° to 30° in any normal

or non-normal condition.

Note: Stabilizer trim is not recommended during the steep turn maneuver

because of increased workload during roll out.

Entry

Stabilize airspeed at 250 knots on heading and altitude. Use a normal turn entry.

An increase in pitch is required as the bank angle is increased to maintain constant

altitude. An increase in thrust is required to maintain constant airspeed.

During Turn

Pitch and thrust control are the same as for a normal turn; however, larger pitch

adjustments are required for a given altitude deviation. Trimming during the

maneuver is not recommended. Varying the angle of bank while turning makes

pitch control more difficult. If altitude loss becomes excessive, reduce the angle

of bank as needed to regain positive pitch control.

Smooth and positive control is required. A rapid instrument scan is required to

detect deviations early enough to be corrected by small adjustments.

Attitude Indicator

The attitude indicator is reliable for accurate pitch and bank information

throughout the turn. Precession error does not exist because the IRS is the source

of attitude information.

Vertical Speed Indicator

IRS vertical speed indications are reliable during the turn.

Altimeter

Crosscheck the direction and rate of change, and make smooth minor adjustments

to the pitch attitude for corrections.

7.21

Maneuvers

Airspeed

Airspeed changes very slowly because of small changes in thrust and drag.

Anticipate thrust changes and apply them at the first indication of change on the

airspeed indicator or speed tape (as installed). An increase in thrust is required as

bank angle increases.

Rollout

Roll out at the same rate as used during normal turns. Normally rollout should

begin 15° to 20° prior to the desired heading. A decrease in pitch is required as the

bank angle is decreased to maintain constant altitude. A decrease in thrust is

required to maintain constant airspeed.

Terrain Avoidance

The Ground Proximity Warning System (GPWS) PULL UP Warning occurs when

an unsafe distance or closure rate is detected with terrain below the airplane. The

Look-ahead terrain alerting (as installed) also provides an aural warning when an

unsafe distance is detected from terrain ahead of the airplane. Immediately

accomplish the Terrain Avoidance maneuver found in the non-normal maneuvers

section in the QRH.

Do not attempt to engage the autopilot and/or autothrottle until terrain clearance

is assured.

Traffic Alert and Collision Avoidance System (TCAS)

TCAS is designed to enhance crew awareness of nearby traffic and issue

advisories for timely visual acquisition or appropriate vertical flight path

maneuvers to avoid potential collisions. It is intended as a backup to visual

collision avoidance, application of right-of-way rules and ATC separation.

Use of TA/RA, TA Only, and Transponder Only Modes

TCAS operation should be initiated just before takeoff and continued until just

after landing. Whenever practical, the system should be operated in the TA/RA

mode to maximize system benefits. Operations in the Traffic Advisory (TA) Only

or TCAS Off (Transponder Only) modes, to prevent nuisance advisories and

display clutter, should be in accordance with operator policy.

The responsibility for avoiding collisions still remains with the flight crew and

ATC. Pilots should not become preoccupied with TCAS advisories and displays

at the expense of basic airplane control, normal visual lookout and other crew

duties.

7.22

Maneuvers

Traffic Advisory (TA)

A Traffic Advisory (TA) occurs when nearby traffic meets system minimum

separation criteria, and is indicated aurally and visually on the TCAS traffic

display. A goal of the TA is to alert the pilot of the possibility of an RA. If a TA is

received, immediately accomplish the Traffic Avoidance maneuver in the QRH.

Maneuvers based solely on a TA may result in reduced separation and are not

recommended.

The TA ONLY mode may be appropriate under the following circumstances:

• during takeoff toward known nearby traffic (in visual contact) which

would cause an unwanted RA during initial climb

• during closely spaced parallel runway approaches

• when flying in known close proximity to other airplanes

• in circumstances identified by the operator as having a verified and

significant potential for unwanted or undesirable RAs

• engine out operation.

Resolution Advisory (RA)

When TCAS determines that separation from approaching traffic may not be

sufficient, TCAS issues a Resolution Advisory (RA) aural warning and a pitch

command. Maneuvering is required if any portion of the airplane symbol is within

the red region on the attitude indicator. Flight crews should follow RA commands

using established procedures unless doing so would jeopardize the safe operation

of the airplane or positive visual contact confirms that there is a safer course of

action. If a RA is received, immediately accomplish the Traffic Avoidance

maneuver in the QRH.

Resolution advisories are known to occur more frequently at locations where

traffic frequently converges (e.g. waypoints). This is especially true in RVSM

airspace. Climb or descent profiles should not be modified in anticipation of

avoiding an RA unless specifically requested by ATC.

RA maneuvers require only small pitch attitude changes which should be

accomplished smoothly and without delay. Properly executed, the RA maneuver

is mild and does not require large or abrupt control movements. Remember that

the passengers and flight attendants may not all be seated during this maneuver.

The flight director is not affected by TCAS guidance. Therefore, when complying

with an RA, flight director commands may be followed only if they result in a

vertical speed that satisfies the RA command.

During the RA maneuver, the aircrew attempts to establish visual contact with the

target. However, visual perception of the encounter can be misleading,

particularly at night. The traffic acquired visually may not be the same traffic

causing the RA.

7.23

Maneuvers

Pilots should maintain situational awareness since TCAS may issue RAs in

conflict with terrain considerations, such as during approaches into rising terrain

or during an obstacle limited climb. Continue to follow the planned lateral flight

path unless visual contact with the conflicting traffic requires other action.

Windshear, GPWS, and stall warnings take precedence over TCAS advisories.

Stick shaker must be respected at all times. Complying with RAs may result in

brief exceedance of altitude and/or placard limits. However, even at the limits of

the operating envelope, in most cases sufficient performance is available to safely

maneuver the airplane. Smoothly and expeditiously return to appropriate altitudes

and speeds when clear of conflict. Maneuvering opposite to an RA command is

not recommended since TCAS may be coordinating maneuvers with other

airplanes.

Upset Recovery

For detailed information regarding the nature of upsets, aerodynamic principles,

recommended training and other related information, refer to the Airplane Upset

Recovery Training Aid available through your operator.

An upset can generally be defined as unintentionally exceeding the following

conditions:

• pitch attitude greater than 25 degrees nose up, or

• pitch attitude greater than 10 degrees nose down, or

• bank angle greater than 45 degrees, or

• within above parameters but flying at airspeeds inappropriate for the

conditions.

General

Though flight crews in line operation rarely, if ever, encounter an upset situation,

understanding how to apply aerodynamic fundamentals in such a situation helps

them control the airplane. Several techniques are available for recovering from an

upset. In most situations, if a technique is effective, it is not recommended that

pilots use additional techniques. Several of these techniques are discussed in the

example scenarios below:

• stall recovery

• nose high, wings level

• nose low, wings level

• high bank angles

• nose high, high bank angles

• nose low, high bank angles

7.24

Maneuvers

Stall Recovery

In all upset situations, it is necessary to recover from a stall before applying any

other recovery actions. A stall may exist at any attitude and may be recognized by

continuous stick shaker activation accompanied by one or more of the following:

• buffeting which could be heavy at times

• lack of pitch authority and/or roll control

• inability to arrest descent rate.

If the airplane is stalled, recovery from the stall must be accomplished first by

applying and maintaining nose down elevator until stall recovery is complete and

stick shaker activation ceases. Under certain conditions, it may be necessary to

reduce some thrust in order to prevent the angle of attack from continuing to

increase. Once stall recovery is complete, upset recovery actions may be taken and

thrust reapplied as needed.

Nose High, Wings Level

In a situation where the airplane pitch attitude is unintentionally more than 25

degrees nose high and increasing, the airspeed is decreasing rapidly. As airspeed

decreases, the pilot's ability to maneuver the airplane also decreases. If the

stabilizer trim setting is nose up, as for slow-speed flight, it partially reduces the

nose-down authority of the elevator. Further complicating this situation, as the

airspeed decreases, the pilot could intuitively make a large thrust increase. This

causes an additional pitch up. At full thrust settings and very low airspeeds, the

elevator, working in opposition to the stabilizer, has limited control to reduce the

pitch attitude.

In this situation the pilot should trade altitude for airspeed, and maneuver the

airplane's flight path back toward the horizon. This is accomplished by the input

of up to full nose-down elevator and the use of some nose-down stabilizer trim.

These actions should provide sufficient elevator control power to produce a

nose-down pitch rate. It may be difficult to know how much stabilizer trim to use,

and care must be taken to avoid using too much trim. Pilots should not fly the

airplane using stabilizer trim, and should stop trimming nose down when they feel

the g force on the airplane lessen or the required elevator force lessen. This use of

stabilizer trim may correct an out-of-trim airplane and solve a less-critical

problem before the pilot must apply further recovery measures. Because a large

nose-down pitch rate results in a condition of less than 1 g, at this point the pitch

rate should be controlled by modifying control inputs to maintain between 0 to 1

g. If altitude permits, flight tests have determined that an effective way to achieve

a nose-down pitch rate is to reduce some thrust.

7.25

Maneuvers

If normal pitch control inputs do not stop an increasing pitch rate, rolling the

airplane to a bank angle that starts the nose down should work. Bank angles of

about 45 degrees, up to a maximum of 60 degrees, could be needed. Unloading the

wing by maintaining continuous nose-down elevator pressure keeps the wing

angle of attack as low as possible, making the normal roll controls as effective as

possible. With airspeed as low as stick shaker onset, normal roll controls - up to

full deflection of ailerons and spoilers - may be used. The rolling maneuver

changes the pitch rate into a turning maneuver, allowing the pitch to decrease.

Finally, if normal pitch control then roll control is ineffective, careful rudder input

in the direction of the desired roll may be required to induce a rolling maneuver

for recovery.

Only a small amount of rudder is needed. Too much rudder applied too quickly or

held too long may result in loss of lateral and directional control. Because of the

low energy condition, pilots should exercise caution when applying rudder.

The reduced pitch attitude allows airspeed to increase, thereby improving elevator

and aileron control effectiveness. After the pitch attitude and airspeed return to a

desired range the pilot can reduce angle of bank with normal lateral flight controls

and return the airplane to normal flight.

Nose Low, Wings Level

In a situation where the airplane pitch attitude is unintentionally more than 10

degrees nose low and going lower, the airspeed is increasing rapidly. A pilot

would likely reduce thrust and extend the speedbrakes. Thrust reduction causes an

additional nose-down pitching moment. Speedbrake extension causes a nose-up

pitching moment, an increase in drag, and a decrease in lift for the same angle of

attack. At airspeeds well above VMO/MMO, the ability to command a nose-up

pitch rate with elevator may be reduced because of the extreme aerodynamic loads

on the elevator.

Again, it is necessary to maneuver the airplane's flight path back toward the

horizon. At moderate pitch attitudes, applying nose-up elevator, reducing thrust,

and extending speedbrakes, if necessary, changes the pitch attitude to a desired

range. At extremely low pitch attitudes and high airspeeds (well above

VMO/MMO), nose-up elevator and nose-up trim may be required to establish a

nose-up pitch rate.

High Bank Angles

A high bank angle is one beyond that necessary for normal flight. Though the bank

angle for an upset has been defined as unintentionally more than 45 degrees, it is

possible to experience bank angles greater than 90 degrees.

7.26

Maneuvers

Any time the airplane is not in “zero-angle-of-bank” flight, lift created by the

wings is not being fully applied against gravity, and more than 1 g is required for

level flight. At bank angles greater than 67 degrees, level flight cannot be

maintained within AFM load factor limits. In high bank angle increasing airspeed

situations, the primary objective is to maneuver the lift of the airplane to directly

oppose the force of gravity by rolling (in the shortest direction) to wings level.

Applying nose-up elevator at bank angles above 60 degrees causes no appreciable

change in pitch attitude and may exceed normal structure load limits as well as the

wing angle of attack for stall. The closer the lift vector is to vertical (wings level),

the more effective the applied g is in recovering the airplane.

A smooth application of up to full lateral control should provide enough roll

control power to establish a very positive recovery roll rate. If full roll control

application is not satisfactory, it may even be necessary to apply some rudder in

the direction of the desired roll.

Only a small amount of rudder is needed. Too much rudder applied too quickly or

held too long may result in loss of lateral and directional control or structural

failure.

Nose High, High Bank Angles

A nose high, high angle of bank upset requires deliberate flight control inputs. A

large bank angle is helpful in reducing excessively high pitch attitudes. The pilot

must apply nose-down elevator and adjust the bank angle to achieve the desired

rate of pitch reduction while considering energy management. Once the pitch

attitude has been reduced to the desired level, it is necessary only to reduce the

bank angle, ensure that sufficient airspeed has been achieved, and return the

airplane to level flight.

Nose Low, High Bank Angles

The nose low, high angle of bank upset requires prompt action by the pilot as

altitude is rapidly being exchanged for airspeed. Even if the airplane is at a high

enough altitude that ground impact is not an immediate concern, airspeed can

rapidly increase beyond airplane design limits. Simultaneous application of roll

and adjustment of thrust may be necessary. It may be necessary to apply

nose-down elevator to limit the amount of lift, which will be acting toward the

ground if the bank angle exceeds 90 degrees. This also reduces wing angle of

attack to improve roll capability. Full aileron and spoiler input should be used if

necessary to smoothly establish a recovery roll rate toward the nearest horizon. It

is important to not increase g force or use nose-up elevator or stabilizer until

approaching wings level. The pilot should also extend the speedbrakes as needed.

7.27

Maneuvers

Upset Recovery Techniques

It is possible to consolidate and incorporate recovery techniques into two basic

scenarios, nose high and nose low, and to acknowledge the potential for high bank

angles in each scenario described above. Other crew actions such as recognizing

the upset, reducing automation, and completing the recovery are included in these

techniques. The recommended techniques provide a logical progression for

recovering an airplane.

If an upset situation is recognized, immediately accomplish the Upset Recovery

maneuver found in the non-normal maneuvers section in the QRH.

Windshear

General

Improper or ineffective vertical flight path control has been one of the primary

factors in many cases of flight into terrain. Low altitude windshear encounters are

especially significant because windshear can place the crew in a situation which

requires the maximum performance capability of the airplane. Windshear

encounters near the ground are the most threatening because there is very little

time or altitude to respond to and recover from an encounter.

Airplane Performance in Windshear

Knowledge of how windshear affects airplane performance can be essential to the

successful application of the proper vertical flight path control techniques during

a windshear encounter.

The wind component is mostly horizontal at altitudes below 500 feet. Horizontal

windshear may improve or degrade vertical flight path performance. Windshear

that improves performance is first indicated in the flight deck by an increasing

airspeed. This type of windshear may be a precursor of a shear that decreases

airspeed and degrades vertical flight path performance.

Airspeed decreases if the tailwind increases, or headwind decreases, faster than

the airplane is accelerating. As the airspeed decreases, the airplane normally tends

to pitch down to maintain or regain the in-trim speed. The magnitude of pitch

change is a function of the encountered airspeed change. If the pilot attempts to

regain lost airspeed by lowering the nose, the combination of decreasing airspeed

and decreasing pitch attitude produces a high rate of descent. Unless this is

countered by the pilot, a critical flight path control situation may develop very

rapidly. As little as 5 seconds may be available to recognize and react to a

degrading vertical flight path.

7.28

Maneuvers

In critical low altitude situations, trade airspeed for altitude, if possible. An

increase in pitch attitude, even though the airspeed may be decreasing, increases

the lifting force and improves the flight path angle. Proper pitch control, combined

with maximum available thrust, utilizes the total airplane performance capability.

The crew must be aware of the normal values of airspeed, altitude, rate of climb,

pitch attitude and control column forces. Unusual control column force may be

required to maintain or increase pitch attitude when airspeed is below the in-trim

speed. If significant changes in airspeed occur and unusual control forces are

required, the crew should be alerted to a possible windshear encounter and be

prepared to take action.

Avoidance, Precautions and Recovery

Crew actions are divided into three areas: Avoidance, Precautions and Recovery.

For more information on avoidance and precautions, see the Windshear

supplementary procedure in Volume 1 of the FCOM. For specific crew actions for

recovery, see the Non-Normal Maneuvers section in the QRH.

7.29

Non-Normal Operations

Chapter 8

Table of Contents

Section TOC

8.TOC Non-Normal Operations-Table of Contents

Preface

8.1

Non-Normal Situation Guidelines

8.1

Troubleshooting

8.2

Approach and Landing

8.3

Landing at the Nearest Suitable Airport

8.3

Air Systems

8.4

Cabin Altitude Warning

8.4

Ditching

8.5

Send Distress Signals

8.5

Advise Crew and Passengers

8.5

Fuel Burn-Off

8.5

Passenger Cabin Preparation

8.5

Ditching Final

8.5

Initiate Evacuation

8.6

Electrical

8.6

Approach and Landing on Standby Power

8.6

Engines, APU

8.6

Engine Failure vs Engine Fire After Takeoff

8.6

Engine Tailpipe Fire

8.7

Loss of Engine Thrust Control

8.7

Loss of Thrust on Both Engines

8.8

Engine Severe Damage Accompanied by High Vibration

8.8

Recommended Technique for an In-Flight Engine Shutdown

8.9

8.TOC.1

Non-Normal Operations -

Table of Contents

Evacuation

8.9

Method of Evacuation

8.10

Discharging Fire Bottles during an Evacuation

8.10

Flight Controls

8.11

Leading Edge or Trailing Edge Device Malfunctions

8.11

Flap Extension using the Alternate System

8.13

Jammed or Restricted Flight Controls

8.13

Stabilizer Trim Inoperative

8.15

Runaway Stabilizer

8.16

Manual Stabilizer Trim

8.16

Standby Rudder On (As Installed)

8.17

Flight Instruments, Displays

8.17

Airspeed Unreliable

8.17

Fuel

8.18

Fuel Balance

8.18

Fuel Leak

8.19

Low Fuel

8.20

Hydraulics

8.20

Hydraulic System(s) Inoperative - Landing

8.20

Landing Gear

8.22

Tire Failure during or after Takeoff

8.22

Landing on a Flat Tire

8.22

Partial or Gear Up Landing

8.23

Overspeed

8.25

Tail Strike

8.26

Takeoff Risk Factors

8.26

8.TOC.2

Non-Normal Operations

Chapter 8

Preface

This chapter describes pilot techniques associated with accomplishing selected

Non-Normal Checklists (NNCs) and provides guidance for situations beyond the

scope of NNCs. Aircrews are expected to accomplish NNCs listed in the QRH.

These checklists ensure maximum safety until appropriate actions are completed

and a safe landing is accomplished. Techniques discussed in this chapter minimize

workload, improve crew coordination, enhance safety, and provide a basis for

standardization. A thorough review of the QRH section CI.2, (Checklist

Introduction, Non-Normal Checklists), is an important prerequisite to

understanding this chapter.

Non-Normal Situation Guidelines

When a non-normal situation occurs, the following guidelines apply:

• NON-NORMAL RECOGNITION: The crewmember recognizing the

malfunction calls it out clearly and precisely

• MAINTAIN AIRPLANE CONTROL: It is mandatory that the Pilot

Flying (PF) fly the airplane while the Pilot Monitoring (PM)

accomplishes the NNC. Maximum use of the autoflight system is

recommended to reduce crew workload

• ANALYZE THE SITUATION: NNCs should be accomplished only after

the malfunctioning system has been positively identified

Note: Pilots should don oxygen masks and establish communications

anytime oxygen deprivation or air contamination is suspected, even

though an associated warning has not occurred.

8.1

Non-Normal Operations

• TAKE THE PROPER ACTION: Although many in-flight non-normal

situations require immediate corrective action, difficulties can be

compounded by the rate the PF issues commands and the speed of

execution by the PM. Commands must be clear and concise, allowing

time for acknowledgment of each command prior to issuing further

commands. The PF must exercise positive control by allowing time for

acknowledgment and execution. The other crewmembers must be certain

their reports to the PF are clear and concise, neither exaggerating nor

understating the nature of the non-normal situation. This eliminates

confusion and ensures efficient, effective, and expeditious handling of the

non-normal situation

• EVALUATE THE NEED TO LAND: If the NNC directs the crew to land

at the nearest suitable airport, or if the situation is so identified in the

QRH section CI.2, (Checklist Introduction, Non-Normal Checklists),

diversion to the nearest airport where a safe landing can be accomplished

is required. If the NNC or the Checklist Introduction do not direct landing

at the nearest suitable airport, the pilot must determine if continued flight

to destination may compromise safety.

Troubleshooting

Troubleshooting can be defined as taking steps beyond the published checklist in

an effort to improve or correct a non-normal condition. Examples of this are:

• attempting to reset a system, or cycling a circuit breaker when not

prescribed by the NNC

• using maintenance-level information to dictate crew actions

• use of switches and controls intended only for maintenance.

Troubleshooting is rarely helpful and has caused further loss of system function

or failure, and in some cases, accidents and incidents. The crew should consider

additional actions beyond the checklist only when completion of the published

checklist steps clearly result in an unacceptable situation. In the case of airplane

controllability problems when a safe landing is considered unlikely, airplane

handling evaluations with gear, flaps or speedbrakes extended may be appropriate.

Also, attempting to free jammed flight controls should only be attempted if the

airplane cannot be safely landed with the existing condition and then, according

to the NNC to the extent possible.

Crew distraction, caused by preoccupation with troubleshooting, has been a key

factor in fuel starvation and CFIT accidents. Boeing recommends completion of

the NNC as published whenever possible, in particular for flight control

malfunctions that are addressed by a NNC. Guidance for situations beyond the

scope of the non-normal checklist is provided later in this chapter.

8.2

Non-Normal Operations

Approach and Landing

When a non-normal situation occurs, a rushed approach can often complicate the

situation. Unless circumstances require an immediate landing, complete all

corrective actions before beginning the final approach.

For some non-normal conditions, the possibility of higher airspeed on approach,

longer landing distance, a different flare picture or a different landing technique

should be considered.

Plan an extended straight-in approach with time allocated for the completion of

any lengthy NNC steps such as the use of alternate flap or landing gear extension

systems. Arm autobrakes and speedbrakes unless precluded by the NNC.

Note: The use of autobrakes is recommended because maximum autobraking

may be more effective than maximum manual braking due to timely

application upon touchdown and symmetrical braking. However, the

Advisory Information in the PI chapter of the QRH provides Non-normal

Configuration Landing Distance data based upon the use of maximum

manual braking. When used properly, maximum manual braking provides

the shortest stopping distance.

Fly a normal glide path and attempt to land in the normal touchdown zone. After

landing, use available deceleration measures to bring the airplane to a complete

stop on the runway. The captain must determine if an immediate passenger

evacuation should be accomplished or if the airplane can be safely taxied off the

runway.

Landing at the Nearest Suitable Airport

“Plan to land at the nearest suitable airport” is a phrase used in the QRH. This

section explains the basis for that statement and how it is applied.

In a non-normal situation, the pilot-in-command, having the authority and

responsibility for operation and safety of the flight, must make the decision to

continue the flight as planned or divert. In an emergency situation, this authority

may include necessary deviations from any regulation to meet the emergency. In

all cases, the pilot-in-command is expected to take a safe course of action.

The QRH assists flight crews in the decision making process by indicating those

situations where “landing at the nearest suitable airport” is required. These

situations are described in the Checklist Introduction or the individual NNC.

The regulations regarding an engine failure are specific. Most regulatory agencies

specify that the pilot-in-command of a twin engine airplane that has an engine

failure or engine shutdown shall land at the nearest suitable airport at which a safe

landing can be made.

8.3

Non-Normal Operations

A suitable airport is defined by the operating authority for the operator based on

guidance material, but in general must have adequate facilities and meet certain

minimum weather and field conditions. If required to divert to the nearest suitable

airport (twin engine airplanes with an engine failure), the guidance material also

typically specifies that the pilot should select the nearest suitable airport “in point

of time” or “in terms of time.” In selecting the nearest suitable airport, the

pilot-in-command should consider the suitability of nearby airports in terms of

facilities and weather and their proximity to the airplane position. The

pilot-in-command may determine, based on the nature of the situation and an

examination of the relevant factors, that the safest course of action is to divert to

a more distant airport than the nearest airport. For example, there is not necessarily

a requirement to spiral down to the airport nearest the airplane's present position

if, in the judgment of the pilot-in-command, it would require equal or less time to

continue to another nearby airport.

For persistent smoke or a fire which cannot positively be confirmed to be

completely extinguished, the safest course of action typically requires the earliest

possible descent, landing and passenger evacuation. This may dictate landing at

the nearest airport appropriate for the airplane type, rather than at the nearest

suitable airport normally used for the route segment where the incident occurs.

Air Systems

Cabin Altitude Warning

There have been several reports of cabin altitude warning alerts caused by

improperly configured engine bleed air and air conditioning pack switches. This

condition is often the result of crews failing to reconfigure switches following a

no engine bleed takeoff. Additionally, there have been reports of crews delaying

their response to the cabin altitude warning alert because it was confused with the

takeoff configuration warning horn.

In order to address the problem of incorrectly positioning switches that affect

pressurization, the normal takeoff procedure has been modified to direct the crew

to set or verify the correct position of the engine bleed air and air conditioning

pack switches after flap retraction is complete. Engine bleeds and air conditioning

packs have also been included as specific items in the After Takeoff normal

checklist. Additionally, when doing a no engine bleed takeoff, reference to the No

Engine Bleed Takeoff supplementary procedure, in conjunction with good crew

coordination, reduces the possibility of crew errors.

8.4

Non-Normal Operations

Confusion between the cabin altitude warning horn and the takeoff configuration

warning horn can be resolved if the crew remembers that the takeoff configuration

warning horn is only armed when the airplane is on the ground. If this horn is

activated in flight, it indicates that the cabin altitude has reached 10,000 feet. In

this case, the crew should immediately initiate the Cabin Altitude Warning or

Rapid Depressurization NNC.

Ditching

Send Distress Signals

Transmit Mayday, current position, course, speed, altitude, situation, intention,

time and position of intended touchdown, and type of airplane using existing

air-to-ground frequency. Set transponder code 7700 and, if practical, determine

the course to the nearest ship or landfall.

Advise Crew and Passengers

Alert the crew and the passengers to prepare for ditching. Assign life raft positions

(as installed) and order all loose equipment in the airplane secured. Put on life

vests, shoulder harnesses, and seat belts. Do not inflate life vests until after exiting

the airplane.

Fuel Burn-Off

Consider burning off fuel prior to ditching, if the situation permits. This provides

greater buoyancy and a lower approach speed. However, do not reduce fuel to a

critical amount, as ditching with engine power available improves ability to

properly control touchdown.

Passenger Cabin Preparation

Confer with cabin personnel either by interphone or by having them report to the

flight deck in person to ensure passenger cabin preparations for ditching are

complete.

Ditching Final

Transmit final position. Select flaps 40 or landing flaps appropriate for the existing

conditions.

Advise the cabin crew of imminent touchdown. On final approach announce

ditching is imminent and advise crew and passengers to brace for impact.

Maintain airspeed at VREF. Maintain 200 to 300 fpm rate of descent. Plan to

touchdown on the windward side and parallel to the waves or swells, if possible.

To accomplish the flare and touchdown, rotate smoothly to touchdown attitude of

10° to 12°. Maintain airspeed and rate of descent with thrust.

8.5

Non-Normal Operations

Initiate Evacuation

After the airplane has come to rest, proceed to assigned ditching stations and

evacuate as soon as possible, ensuring all passengers are out of the airplane.

Deploy slides/rafts. Be careful not to rip or puncture the slides/rafts. Avoid drifting

into or under parts of the airplane. Remain clear of fuel-saturated water.

Electrical

Approach and Landing on Standby Power

The probability of a total and unrecoverable AC power failure is remote. Because

of system design, a NNC for accomplishing an approach and landing on standby

power is not required. However, some regulatory agencies require pilots to train

for this condition. During training, or in the unlikely event that a landing must be

made on standby power, the following guidelines should be considered.

Complete all applicable NNCs and approach preparations. Manual pressurization

control and manual stabilizer trim are required. The left navigation radios and

communication radio are operable on standby power. Use right ignition. On some

airplanes, the captain's electronic flight instruments and left FMC are available.

Note: Refer to Volume 2, Chapter 6 of the FCOM for a list of significant

equipment powered by standby power.

Fly the approach on speed. Only partial anti-skid is available so excess approach

airspeed is undesirable. Brake with caution. The flap position indicator is

inoperative. Auto brakes and auto speedbrakes are not available. Reverse thrust is

available.

Engines, APU

Engine Failure vs Engine Fire After Takeoff

The NNC for an engine failure is normally accomplished after the flaps have been

retracted and conditions permit.

In case of an engine fire, when the airplane is under control, the gear has been

retracted, and a safe altitude has been attained (minimum 400 feet AGL)

accomplish the NNC recall items. Due to asymmetric thrust considerations,

Boeing recommends that the PF retard the affected thrust lever after the PM

confirms that the PF has identified the correct engine. Reference items should be

accomplished on a non-interfering basis with other normal duties after the flaps

have been retracted and conditions permit.

8.6

Non-Normal Operations

Engine Tailpipe Fire

Engine tailpipe fires are typically caused by engine control malfunctions that

result in the ignition of pooled fuel. These fires can be damaging to the engine and

have caused unplanned passenger evacuations.

If a tailpipe fire is reported, the crew should accomplish the NNC without delay.

Flight crews should consider the following when dealing with this situation:

• motoring the engine is the primary means of extinguishing the fire

• to prevent an inappropriate evacuation, flight attendants should be

notified without significant delay

• communications with ramp personnel and the tower are important to

determine the status of the tailpipe fire and to request fire extinguishing

assistance

• the engine fire checklist is inappropriate because the engine fire

extinguishing agent is not effective against a fire inside the tailpipe.

Loss of Engine Thrust Control

All turbo fan engines are susceptible to this malfunction whether engine control is

hydro-mechanical, hydro-mechanical with supervisory electronics (e.g. PMC) or

Full Authority Digital Engine Control (FADEC). Engine response to a loss of

control varies from engine to engine. Malfunctions have occurred in-flight and on

the ground. The major challenge the flight crew faces when responding to this

malfunction is recognizing the condition and determining which engine has

malfunctioned. This condition can occur during any phase of flight.

Failure of engine or fuel control system components, or loss of thrust lever

position feedback has caused loss of engine thrust control. Control loss may not

be immediately evident since many engines fail to some fixed RPM or thrust lever

condition. This fixed RPM or thrust lever condition may be very near the

commanded thrust level and therefore difficult to recognize until the flight crew

attempts to change thrust with the thrust lever. Other engine responses include:

shutdown, operation at low RPM, or thrust at the last valid thrust lever setting (in

the case of a thrust lever feedback fault) depending on altitude or air/ground logic.

In all cases, the affected engine does not respond to thrust lever movement.

The Engine Limit/Surge/Stall NNC is written to include this malfunction. Since

recognition may be difficult, if a loss of engine control is suspected, the flight crew

should continue the takeoff or remain airborne until the Engine Limit/Surge/Stall

NNC can be accomplished. This helps with directional control and may preclude

an inadvertent shutdown of the wrong engine. In some conditions, such as during

low speed ground operations, immediate engine shutdown may be necessary to

maintain directional control.

8.7

Non-Normal Operations

Loss of Thrust on Both Engines

Dual engine failure is a situation that demands prompt action regardless of altitude

or airspeed. Accomplish recall items and establish the appropriate airspeed to

immediately attempt a windmill restart. There is a higher probability that a

windmill start will succeed if the restart attempt is made as soon as possible (or

immediately after recognizing an engine failure) to take advantage of high engine

RPM. Use of higher airspeeds and altitudes below 30,000 feet improves the

probability of a restart. Loss of thrust at higher altitudes may require descent to a

lower altitude to improve windmill starting capability.

The inflight start envelope defines the region where windmill starts were

demonstrated during certification. It should be noted that this envelope does not

define the only areas where a windmill start may be successful. The dual engine

failure NNC is written to ensure flight crews take advantage of the high RPM at

engine failure regardless of altitude or airspeed. A subsequent APU start may be

initiated as soon as practical to provide electrical power and starter assist during a

subsequent engine start attempt if the rapid restart is not successful. Initiate the

rapid restart recall procedure before attempting an APU start for the reasons

identified above.

During a rapid restart, EGT may exceed the displayed limit for one-engine starts.

During restart attempts with both engines failed, use the takeoff EGT limit. A hung

or stalled in-flight start is normally indicated by stagnant RPM and increasing

EGT. During start, engines may accelerate to idle slowly but action should not be

taken if RPM is increasing and EGT is not near or rapidly approaching the limit.

Note: When electrical power is restored, do not confuse the establishment of

APU generator power with the establishment of engine generator power at

idle RPM and advance the thrust lever prematurely.

Engine Severe Damage Accompanied by High Vibration

Certain engine failures, such as fan blade separation can cause high levels of

airframe vibration. Although the airframe vibration may seem severe to the flight

crew, it is extremely unlikely that the vibration will damage the airplane structure

or critical systems. However, the vibration should be reduced as soon as possible

by reducing airspeed and descending. As altitude and airspeed change, the

airplane may transition through various levels of vibration. In general, vibration

levels decrease as airspeed decreases, however, at a given altitude vibration may

temporarily increase or decrease as airspeed changes.

If vibration remains unacceptable, descending to a lower altitude (terrain

permitting) allows a lower airspeed and normally lower vibration levels. Vibration

will likely become imperceptible as airspeed is further reduced during approach.

8.8

Non-Normal Operations

The impact of a vibrating environment on human performance is dependent on a

number of factors, including the orientation of the vibration relative to the body.

People working in a vibrating environment may find relief by leaning forward or

backward, standing, or otherwise changing their body position.

Once airframe vibration has been reduced to acceptable levels, the crew must

evaluate the situation and determine a new course of action based on weather, fuel

remaining, and available airports.

Recommended Technique for an In-Flight Engine Shutdown

Any time an engine shutdown is required in flight, good crew coordination is

essential. Airplane incidents have turned into airplane accidents as a result of the

flight crew shutting down the incorrect engine.

When the flight path is under complete control, the crew should proceed with a

deliberate, systematic process that identifies the correct engine and ensures that

the incorrect engine is not shut down. Do not rush through the shutdown

procedure, even for a fire indication. Operators may develop their own crew

coordination techniques that meet these objectives. The following technique is an

example that could be used:

When an engine shutdown is required, the PF verbally confirms the correct engine

with the PM, then disconnects the A/T and slowly retards the thrust lever of the

engine that will be shutdown.

Coordinate activation of the start lever as follows:

• PM places a hand on and verbally identifies the start lever for the engine

that will be shutdown

• PF verbally confirms that the PM has identified the correct engine

• PF directs the PM to move the start lever to cutoff.

If the NNC requires activation of the engine fire switch, coordinate as follows:

• PM places a hand on and verbally identifies the engine fire switch for the

engine that will be shutdown

• PF verbally confirms that the PM has identified the correct engine

• PF directs the PM to pull engine fire switch.

Evacuation

If an evacuation is planned and time permits, a thorough briefing and preparation

of the crew and passengers will increase the chances of a successful evacuation.

Flight deck preparations should include a review of pertinent checklists and any

other actions to be accomplished. Appropriate use of autobrakes should be

discussed. If evacuating due to fire in windy conditions, consider positioning the

airplane so the fire is on the downwind side.

8.9

Non-Normal Operations

Notify cabin crew of possible adverse conditions at the affected exits. The

availability of various exits may differ for each situation. Crewmembers must

make the decision as to which exits are usable for the circumstances.

For unplanned evacuations, the captain needs to analyze the situation carefully

before initiating an evacuation order. Quick actions in a calm and methodical

manner will improve the chances for a successful passenger evacuation.

Method of Evacuation

When there is a need to evacuate passengers and crew, the captain has to choose

between commanding an emergency evacuation using the emergency escape

slides or less urgent means such as deplaning using stairs, jetways, or other means.

All available sources of information should be used to determine the safest course

of action including reports from the cabin crew, other aircraft, and air traffic

control. The captain must then determine the best means of passenger evacuation

by carefully considering all factors. These include, but are not limited to:

• the urgency of the situation, including the possibility of significant injury

or loss of life if a significant delay occurs

• the type of threat to the airplane, including structural damage, fire,

reported bomb on board, etc.

• the possibility of fire spreading rapidly from spilled fuel or other

flammable materials

• the extent of damage to the airplane

• the possibility of passenger injury during an emergency evacuation using

the escape slides.

If in doubt, the crew should consider an emergency evacuation using the escape

slides.

Discharging Fire Bottles during an Evacuation

The evacuation NNC specifies discharge of the engine or APU fire bottles if an

engine or APU fire warning light is illuminated. However, evacuation situations

can present possibilities regarding the potential for fire that are beyond the scope

of the NNC and may not activate an engine or APU fire warning. The crew should

consider the following when deciding whether to discharge one or more fire

bottles into the engines and/or APU:

• if an engine fire warning light is not illuminated, but a fire indication

exists or a fire is reported in or near an engine, discharge both available

fire bottles into the affected engine

• if the APU fire warning light is not illuminated, but a fire indication exists

or a fire is reported in or near the APU, discharge the APU bottle

8.10

Non-Normal Operations

• the discharged halon agent is designed to extinguish a fire and has very

little or no fire prevention capability in the engine nacelles. Halon

dissipates quickly into the atmosphere

• there is no reason to discharge the engine or APU fire bottles for

evacuations not involving fire indications existing or reported in or near

an engine or APU, e.g., cargo fire, security or bomb threat, etc.

Flight Controls

Leading Edge or Trailing Edge Device Malfunctions

Leading edge or trailing edge device malfunctions can occur during extension or

retraction. This section discusses all flaps up and partial or asymmetrical

leading/trailing edge device malfunctions for landings.

All Flaps Up Landing

The probability of both leading and trailing edge devices failing to extend is

remote. If a flaps up landing situation were to be encountered in service, the pilot

should consider the following techniques. Training to this condition should be

limited to the flight simulator.

After selecting a suitable landing airfield and prior to beginning the approach,

consider reduction of airplane gross weight (burn off fuel) to reduce touchdown

speed.

Fly a wide pattern to allow for the increased turning radius required for the higher

maneuvering speed. Establish final approximately 10 miles from the runway. This

allows time to extend the gear and decelerate to the target speed while in level

flight and complete all required checklists. Maintain no slower than flaps up

maneuvering speed until established on final. Maneuver with normal bank angles

until on final.

Final Approach

Use an ILS glide slope if available. Do not reduce the airspeed to the final

approach speed until aligned with the final approach. Before intercepting the

descent profile, decrease airspeed to command speed and maintain this speed until

the landing is assured.

The normal rate of descent on final is approximately 900 fpm due to the higher

ground speed. Final approach body attitude is approximately 1° - 2° higher than a

flaps 30 approach. Do not make a flat approach (shallow glide path angle) or aim

for the threshold of the runway. Plan touchdown at the 1,000 foot point.

8.11

Non-Normal Operations

Use manual control of thrust levers. Due to automatic speed protection,

autothrottle use may result in higher than desired speed on final. Engines will be

at low idle speed due to no flap extension. When engines are near idle RPM, time

required for engines to accelerate is longer than normal.

Note: Use of the autopilot during approach phase is acceptable. Do not autoland.

Speedbrakes are not recommended for airspeed reduction below 800 feet. If

landing is anticipated beyond the normal touch down zone, go around.

Landing

Fly the airplane onto the runway at the recommended touchdown point. Flare only

enough to achieve an acceptable reduction in the rate of descent. Do not allow the

airplane to float. Floating just above the runway surface to deplete additional

speed wastes available runway and increases the possibility of a tail strike. Do not

risk touchdown beyond the normal touchdown zone in an effort to achieve a

smooth landing.

Slight forward pressure on the control column may be required to achieve

touchdown at the desired point and to lower the nosewheel to the runway. After

lowering the nosewheel to the runway, hold forward control column pressure and

expeditiously accomplish the landing roll procedure. Full reverse thrust is

required for a longer period of time.

Use of autobrakes is recommended. Autobrake setting should be consistent with

runway length. Use manual braking if deceleration is not suitable for the desired

stopping distance.

Immediate initiation of reverse thrust at main gear touchdown (reverse thrust is

more effective at high speeds) and full reverse thrust allows the autobrake system

to reduce brake pressure to the minimum level. Less than maximum reverse thrust

increases brake energy requirements and may result in excessive brake

temperatures.

Leading Edge Flaps Transit - Landing

If an asymmetrical or skewed leading edge device condition occurs, the adjusted

VREF provides 15° bank angle maneuvering capability and allows for 15°

overshoot protection in all cases.

Do not hold the airplane off during landing flare. Floating just above the runway

surface to deplete the additional threshold speed wastes available runway and

increases the possibility of a tail strike.

Note: If the gear is retracted during a go-around and flap position is greater than

25, a landing gear configuration warning occurs.

8.12

Non-Normal Operations

Trailing Edge Flap Asymmetry - Landing

If a trailing edge flap up asymmetry occurs, full maneuvering capability exists

even if the asymmetry occurred at flaps just out of the full up position. Burn off

fuel to reduce landing weight and lower approach speed.

Fly accurate airspeeds in the landing pattern. At lesser flap settings, excess

airspeed is difficult to dissipate, especially when descending on final approach.

Pitch attitude and rate of descent on final is higher than for a normal landing.

During flare, airspeed does not bleed off as rapidly as normal.

Fly the airplane onto the runway at the recommended touchdown point. Flare only

enough to achieve an acceptable reduction in the rate of descent. Do not allow the

airplane to float. Floating just above the runway surface to deplete additional

speed wastes available runway and increases the possibility of a tail strike. Do not

risk touchdown beyond the normal touchdown zone in an effort to achieve a

smooth landing.

Note: If the gear is retracted during a go-around and flap position is greater than

25, a landing gear configuration warning occurs.

Flap Extension using the Alternate System

When extending the flaps using the alternate system, the recommended method

for setting command speed differs from the method used during normal flap

extension. Since the flaps extend more slowly when using the alternate system, it

is recommended that the crew delay setting the new command speed until the flaps

reach the selected position. This method may prevent the crew from inadvertently

getting into a low airspeed condition if attention to airspeed is diverted while

accomplishing other duties.

Jammed or Restricted Flight Controls

Although rare, jamming of the flight control system has occurred on commercial

airplanes. A jammed flight control can result from ice accumulation due to water

leaks onto cables or components, dirt accumulation, component failure such as

cable break or worn parts, improper lubrication, or foreign objects.

A flight control jam may be difficult to recognize, especially in a properly

trimmed airplane. A jam in the pitch axis may be more difficult to recognize than

a jam in other axes. In the case of the elevator, the jammed control can be masked

by trim. Some indications of a jam are:

• unexplained autopilot disconnect

• autopilot that cannot be engaged

• undershoot or overshoot of an altitude during autopilot level-off

• higher than normal control forces required during speed or configuration

changes

8.13

Non-Normal Operations

If any jammed flight control condition exists, both pilots should apply force to try

to either clear the jam or activate the override feature. There should be no concern

about damaging the flight control mechanism by applying too much force to either

clear a jammed flight control or activate an override feature. Maximum force may

result in some flight control surface movement with a jammed flight control. If the

jam clears, both pilot’s flight controls are available.

Note: If a control is jammed due to ice accumulation, the jam may clear when

moving to a warmer temperature.

Some flight controls are linked together through override features. If the jam does

not clear, activation of an override feature allows a flight control surface to be

moved independent of the jammed control. Applying force to the non-jammed

flight control activates the override feature. When enough force is applied, the

jammed control is overridden allowing the non-jammed control to operate. To

identify the non-jammed flight control, apply force to each flight control

individually. The flight control that results in the greatest airplane control is the

non-jammed control.

Note: The pilot of the non-jammed control should be the pilot flying for the

remainder of the flight.

The non-jammed control requires a normal force, plus an additional override force

to move the flight control surface. For example, if a force of 10 lbs (4 kg) is

normally required to move the surface, and 50 lbs (23 kg) of force is required to

activate the override, a total force of 60 lbs (27 kg) is required to move the control

surface while in override. Response is slower than normal with a jammed flight

control; however, sufficient response is available for airplane control and landing.

For those controls without override features, limited flight control surface

deflection occurs when considerable force is applied to the flight control. This

response is due to cable stretch and structural bending. This response may be

sufficient for airplane control and landing.

Note: There is an override feature that allows control of the ailerons or spoilers.

There is also an override feature that allows control of the elevator in the

event of a control column jam.

Trim Inputs

If a jammed flight control condition exists, use manual inputs from other control

surfaces to counter pressures and maintain a neutral flight control condition. The

following table provides trim inputs that may be used to counter jammed flight

control conditions.

8.14

Non-Normal Operations

Jammed Control Surface

Manual Trim Inputs

Elevator

Stabilizer

Aileron

Rudder*

Rudder

Aileron*

*Asymmetric engine thrust may aid roll and directional

control.

Approach and Landing

Attempt to select a runway with minimum crosswind. Complete approach

preparations early. Recheck flight control surface operation prior to landing to

determine if the malfunction still exists. Do not make abrupt thrust, speedbrake,

or configuration changes. Make small bank angle changes. On final approach, do

not reduce thrust to idle until after touchdown. Asymmetrical braking and

asymmetrical thrust reverser deployment may aid directional control on the

runway.

Note: In the event of an elevator jam, control forces will be significantly greater

than normal and control response will be slower than normal to flare the

airplane.

Go Around Procedure

If the elevator is known or suspected to be jammed, a go-around should be avoided

if at all possible. To execute a go-around with a jammed elevator, smoothly

advance throttles while maintaining pitch control with stabilizer and any available

elevator. If a go-around is required, the go-around procedure is handled in the

same manner as a normal go-around.

Stabilizer Trim Inoperative

The stabilizer trim may become inoperative for number of reasons. The most

common reason is a failed stabilizer motor. This failure mode causes a loss of

electric trim through both the autopilot and control wheel switches, but manual

trim is still available using the trim wheels. This failure mode is addressed using

the STABILIZER TRIM INOPERATIVE NNC.

8.15

Non-Normal Operations

Other, less common failure modes that are also addressed using the STABILIZER

TRIM INOPERATIVE NNC include:

• a lodged or stuck stabilizer motor. This failure mode causes a loss of

electric trim through both the autopilot and control wheel switches, but

manual trim is still available using the trim wheels by overriding autopilot

and main electric trim brake systems. The effort required to manually

rotate the trim wheels in this condition is higher than normal

• a lodged or stuck stabilizer actuator. This failure mode causes a loss of

electric trim through both the autopilot and control wheel switches and a

loss of manual trim. The result is a stabilizer that cannot be trimmed.

Flight tests have demonstrated the airplane can be flown and landed safely

with stabilizer trim inoperative

• a lodged or stuck stabilizer actuator can be the result of ice on the

jackscrew. If the crew suspects that the failure could be due to ice

accumulation, descend to a warmer temperature and try again.

Runaway Stabilizer

Hold the control column firmly to maintain the desired pitch attitude. If

uncommanded trim motion continues, the stabilizer trim commands are

interrupted when the control column is displaced in the opposite direction.

Manual Stabilizer Trim

If manual stabilizer trim is necessary, ensure both stabilizer trim cutout switches

are in CUTOUT prior to extending the manual trim wheel handles.

Excessive airloads on the stabilizer may require effort by both pilots to correct the

mis-trim. In extreme cases it may be necessary to aerodynamically relieve the

airloads to allow manual trimming. Accelerate or decelerate towards the in-trim

speed while attempting to trim manually.

Anticipate the trim changes required for the approach. Configure the airplane

early in the approach. When reaching the landing configuration, maintain as

constant a trim setting as possible. If a go-around is required, anticipate the trim

changes as airspeed increases.

8.16

Non-Normal Operations

Standby Rudder On (As Installed)

The STANDBY RUDDER ON light illuminates any time the standby rudder PCU

is operating. If this light illuminates independent of crew action or a hydraulic

system malfunction, either of two conditions may have occurred. The most

probable cause is a force fight monitor malfunction inadvertently activating the

standby pump and powering the standby PCU. In this case, three PCU control

valves power the rudder and full rudder inputs should be avoided to prevent

applying excessive loads on the rudder. The NNC is written for this condition. The

second cause may be because of a pressure difference between the two main PCU

control valves indicating a jammed condition. This condition does not require a

NNC because satisfactory rudder operation is available using the standby rudder

PCU.

Flight Instruments, Displays

Airspeed Unreliable

Unreliable airspeed indications can result from blocking or freezing of the

pitot/static system or a severely damaged or missing radome. When the ram air

inlet to the pitot head is blocked, pressure in the probe is released through the drain

holes and the airspeed slowly drops to zero. If the ram air inlet and the probe drain

holes are both blocked, pressure trapped within the system reacts unpredictably.

The pressure may increase through expansion, decrease through contraction, or

remain constant. In all cases, the airspeed indications would be abnormal. This

could mean increasing indicated airspeed in climb, decreasing indicated airspeed

in descent, or unpredictable indicated airspeed in cruise.

If the flight crew is aware of the problem, flight without the benefit of valid

airspeed information can be safely conducted and should present little difficulty.

Early recognition of erroneous airspeed indications require familiarity with the

interrelationship of attitude, thrust setting, and airspeed. A delay in recognition

could result in loss of airplane control.

The flight crew should be familiar with the approximate pitch attitude for each

flight maneuver. For example, climb performance is based on maintaining a

particular airspeed or Mach number. This results in a specific body attitude that

varies little with gross weight and altitude. Any significant change from the body

attitude required to maintain a desired airspeed should alert the flight crew to a

potential problem.

8.17

Non-Normal Operations

When the abnormal airspeed is recognized, immediately return the airplane to the

target attitude and thrust setting for the flight regime. If continued flight without

valid airspeed indications is necessary, consult the Flight With Unreliable

Airspeed/Turbulent Air Penetration table in the Performance Inflight section of

the QRH for the correct attitude, thrust settings, and V/S for actual airplane gross

weight and altitude.

Ground speed information is available from the FMC and on the instrument

displays. These indications can be used as a cross check. Many air traffic control

radars can also measure ground speed.

For airplanes equipped with an Angle of Attack (AOA) indicator, maintain the

analog needle at approximately the three o’clock position. This approximates a

safe maneuvering speed or approach speed for the existing airplane configuration.

Descent

Idle thrust descents to 10,000 feet can be made by flying body attitude and

checking rate of descent in the QRH tables. At 2,000 feet above the selected level

off altitude, reduce rate of descent to 1,000 FPM. On reaching the selected

altitude, establish attitude and thrust for the airplane configuration. If possible,

allow the airplane to stabilize before changing configuration and altitude.

Approach

If available, accomplish an ILS approach. Establish landing configuration early on

final approach. At glide slope intercept or beginning of descent, set thrust and

attitude per the QRH tables and control the rate of descent with thrust.

Landing

Control the final approach so as to touch down approximately 1,000 feet to 1,500

feet beyond the threshold. Fly the airplane on to the runway, do not hold it off or

let it “float” to touchdown.

Use autobraking if available. If manual braking is used, maintain adequate brake

pedal pressure until a safe stop is assured. Immediately after touchdown,

expeditiously accomplish the landing roll procedure.

Fuel

Fuel Balance

The primary purpose of fuel balance limitations on Boeing airplanes is for the

structural life of the airframe and landing gear and not for controllability. A

reduction in structural life of the airframe or landing gear can be caused by

frequently operating with out-of-limit fuel balance conditions. Lateral control is

not significantly affected when operating with fuel beyond normal balance limits.

8.18

Non-Normal Operations

The primary purpose for fuel balance alerts are to inform the crew that imbalances

beyond the current state may result in increased trim drag and higher fuel

consumption. The IMBAL NNC should be accomplished when the fuel balance

alert is received.

There is a common misconception among flight crews that the fuel crossfeed

valve should be opened immediately after an in-flight engine shutdown to prevent

fuel imbalance. This practice is contrary to Boeing recommended procedures and

could aggravate a fuel imbalance. This practice is especially significant if an

engine failure occurs and a fuel leak is present. Arbitrarily opening the crossfeed

valve and starting fuel balancing procedures, without following the checklist, can

result in pumping usable fuel overboard.

The misconception may be further reinforced during simulator training. The fuel

pumps in simulators are modeled with equal output pressure on all pumps so

opening the crossfeed valve appears to maintain a fuel balance. However, the fuel

pumps in the airplane have allowable variations in output pressure. If there is a

sufficient difference in pump output pressures and the crossfeed valve is opened,

fuel feeds to the operating engine from the fuel tank with the highest pump output

pressure. This may result in fuel unexpectedly coming from the tank with the

lowest quantity.

Fuel Balancing Considerations

The crew should consider the following when performing fuel balancing

procedures:

• use of the Fuel Balancing Supplementary Procedure in conjunction with

good crew coordination reduces the possibility of crew errors

• routine fuel balancing when not near the imbalance limit increases the

possibility of crew errors and does not significantly improve fuel

consumption

• during critical phases of flight, fuel balancing should be delayed until

workload permits. This reduces the possibility crew errors and allows

crew attention to be focused on flight path control

• fuel imbalances that occur during approach need not be addressed if the

reason for the imbalance is obvious (e.g. engine failure or thrust

asymmetry, etc.).

Fuel Leak

Any time an unexpected fuel quantity indication, FMC fuel message, or imbalance

condition is experienced, a fuel leak should be considered as a possible cause.

Maintaining a fuel log and comparing actual fuel burn to the flight plan fuel burn

can help the pilot recognize a fuel leak.

8.19

Non-Normal Operations

Significant fuel leaks, although fairly rare, are difficult to detect. The NNC

assumes the leak is between the strut and the engine. There is no specific fuel leak

annunciation on the flight deck. A leak must be detected by discrepancies in the

fuel log, by visual confirmation, or by some annunciation that occurs because of

a leak. Any unexpected change in fuel quantity or fuel balance should alert the

crew to the possibility of a leak. If a leak is suspected, it is imperative to follow

the NNC.

Low Fuel

A low fuel condition exists when the fuel LOW indication is displayed.

Approach and Landing

In a low fuel condition, the clean configuration should be maintained as long as

possible during the descent and approach to conserve fuel. However, initiate

configuration changes early enough to provide a smooth, slow deceleration to

final approach speed to prevent fuel from running forward in the tanks.

A normal landing configuration and airspeed appropriate for the wind conditions

are recommended.

Runway conditions permitting, heavy braking and high levels of reverse thrust

should be avoided to prevent uncovering all fuel pumps and possible engine

flameout during landing roll.

Go-Around

If a go-around is necessary, apply thrust slowly and smoothly and maintain the

minimum nose-up body attitude required for a safe climb gradient. Avoid rapid

acceleration of the airplane. If any wing tank fuel pump low pressure light

illuminates, do not turn the fuel pump switches off.

Hydraulics

Proper planning of the approach is important. Consideration should be given to the

effect the inoperative system(s) has on crosswind capabilities, autoflight,

stabilizer trim, control response, control feel, reverse thrust, stopping distance,

go-around configuration and performance required to reach an alternate airfield.

Hydraulic System(s) Inoperative - Landing

If the landing gear is extended using manual gear extension, the gear cannot be

raised. Trailing edge flaps can be extended or retracted using the alternate

(electric) system. However, the rate of flap travel is significantly reduced. Leading

edge devices can also be extended using the alternate system, but they cannot be

retracted.

8.20

Non-Normal Operations

Flaps 15 is used to improve go-around capabilities. The airplane may tend to float

during the flare. Do not allow the airplane to float. Fly the airplane onto the

runway at the recommended point.

If nose wheel steering is inoperative and any crosswind exists, consideration

should be given to landing on a runway where braking action is reported as good

or better. Braking action becomes the primary means of directional control below

approximately 60 knots where the rudder becomes less effective. If controllability

is satisfactory, taxi clear of the runway using differential thrust and brakes.

Continued taxi with nose wheel steering inoperative is not recommended due to

airplane control difficulties and heat buildup in the brakes.

Manual Reversion

With both hydraulic systems A and B inoperative, the ailerons and elevator are

controlled manually. A noticeable dead band will be observed in both of these

controls. High control forces are required for turns and the control wheel must be

forcibly returned to the aileron neutral position.

Both electric and manual trim are still functional. Do not overtrim. The airplane

should be trimmed slightly nose up and a light forward pressure held on the

control column to minimize the effects of the elevator dead band.

The rudder is powered by the standby hydraulic system. Caution must be

exercised to not overcontrol the rudder.

Note: The standby rudder includes a yaw damper which aids roll control

handling qualities in the aileron dead band area during manual reversion.

Fly a long straight-in approach. Keep thrust changes small and slow to allow for

pitch trim changes. Landing configuration and approach airspeed should be

established on the runway centerline so that only a slight reduction in thrust is

required to achieve the landing profile. Do not make a flat approach. Anticipate

the airplane will tend to pitch down as thrust is reduced for touchdown. This pitch

down tendency is reduced if the airplane is trimmed slightly nose up to minimize

the effects of the elevator dead band.

After touchdown, thrust reverser operation is slow. Apply steady brake pressure

since only accumulator pressure is available. Do not apply excessive forward

pressure to the control column. Excessive forward pressure without the

speedbrakes deployed can result in less weight on the main gear and reduced

braking capability.

Do not attempt to taxi the airplane after stopping because the accumulator pressure

may be depleted or close to being depleted.

If a go-around is required, apply thrust smoothly and in coordination with

stabilizer trim. Rapid thrust application results in nose-up pitch forces.

8.21

Non-Normal Operations

Landing Gear

Tire Failure during or after Takeoff

If the crew suspects a tire failure during takeoff, the ATS facility serving the

departing airport should be advised of the potential for tire pieces remaining on

the runway. The crew should consider continuing to the destination unless there is

an indication that other damage has occurred (non-normal engine indications,

engine vibrations, hydraulic system failures or leaks, etc.).

Continuing to the destination will allow the airplane weight to be reduced

normally, and provide the crew an opportunity to plan and coordinate their arrival

and landing when the workload is low.

Considerations in selecting a landing airport include, but are not limited to:

• sufficient runway length and acceptable surface conditions to account for

the possible loss of braking effectiveness

• sufficient runway width to account for possible directional control

difficulties

• altitude and temperature conditions that could result in high ground

speeds on touchdown and adverse taxi conditions

• runway selection options regarding "taxi-in" distance after landing

• availability of operator maintenance personnel to meet the airplane after

landing to inspect the wheels, tires, and brakes before continued taxi

• availability of support facilities should the airplane need repair.

Landing on a Flat Tire

Boeing airplanes are designed so that the landing gear and remaining tire(s) have

adequate strength to accommodate a flat nose gear tire or main gear tire. When the

pilot is aware of a flat tire prior to landing, use normal approach and flare

techniques, avoid landing overweight and use the center of the runway. Use

differential braking as required for directional control. With a single tire failure,

towing is not necessary unless unusual vibration is noticed or other failures have

occurred.

In the case of a flat nose wheel tire, slowly and gently lower the nose wheel to the

runway while braking lightly. Runway length permitting, use idle reverse thrust.

Autobrakes may be used at the lower settings. Once the nose gear is down,

vibration levels may be affected by increasing or decreasing control column back

pressure. Maintain nose gear contact with the runway.

Flat main gear tire(s) cause a general loss of braking effectiveness and a yawing

moment toward the flat tire with light or no braking and a yawing moment away

from the flat tire if the brakes are applied harder. Maximum use of reverse thrust

is recommended. Do not use autobrakes.

8.22

Non-Normal Operations

If uncertain whether a nose tire or a main tire has failed, slowly and gently lower

the nose wheel to the runway and do not use autobrakes. Differential braking may

be required to steer the airplane. Use idle or higher reverse thrust as required to

stop the airplane.

Note: Extended taxi distances or fast taxi speeds can cause significant increases

in temperatures on the remaining tires.

Partial or Gear Up Landing

Land on all available gear. The landing gear absorbs the initial shock and delays

touchdown of airplane body parts. Recycling the landing gear in an attempt to

extend the remaining gear is not recommended. A gear up or partial gear landing

is preferable to running out of fuel while attempting to solve a gear problem.

Landing Runway

Consideration should be given to landing at the most suitable airport with

adequate runway and fire fighting capability. Foaming the runway is not

necessary. Tests have shown that foaming provides minimal benefit and it takes

approximately 30 minutes to replenish the fire truck’s foam supply.

Prior to Approach

If time and conditions permit, reduce weight as much as possible by burning off

fuel to attain the slowest possible touchdown speed.

At the captain’s command, advise the crew and the passengers of the situation, as

needed. Coordinate with all ground emergency facilities. For example, fire trucks

normally operate on a common VHF frequency with the airplane and can advise

the crew of the airplane condition during the landing. Advise the cabin crew to

perform emergency landing procedures and to brief passengers on evacuation

procedures.

The NNC instructs the crew to inhibit the ground proximity system as needed to

prevent nuisance warnings when close to the ground with the gear retracted.

For landing in any gear configuration, establish approach speed early and maintain

a normal rate of descent.

Landing Techniques

Attempt to keep the airplane on the runway to minimize airplane damage and aid

in passenger evacuation. After touchdown lower the nose gently before losing

elevator effectiveness. Use all aerodynamic capability to maintain directional

control on the runway. At touchdown speed the rudder has sufficient authority to

provide directional control in most configurations. At speeds below 60 knots, use

nose wheel/rudder pedal steering, if available, and differential braking as needed.

8.23

Boeing 737 - 600/700/800/900. Flight Crew Training Manual (1999 year) - page 8