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WT9 Dynamic LSA. AIRCRAFT MAINTENANCE MANUAL (AS-AMM-01-000, 22. 05. 2017) - page 24

NOSE GEAR

LANDING GEAR

(k) On the rear side of the clip assembly, unscrew the nuts (16), remove

the washers (15) and the bolts (13).

NOTE

Clip assembly consists of pos. 7, 8, 9.

(l)

On clip assembly, unscrew the nuts (16) remove the washers (15),
washers (34) and the bolts (14).

(m) Remove the clip assembly, stirrup (27) with beams (28).

(n) On the stirrup, remove the split pins (33), remove the washers (15),

bolts (31) and remove the beams.

(o) Remove the nose landing gear (1).

(p) Remove the upper and lower supports (see 2.D.(1)).

(q) As necessary, remove the carbon fork (18) and the braking plate (21):

•

Remove the carbon fork (18), by removing the nuts (16), washers

(15), bolts (19) and washer plate (20).

•

Remove the braking plate (21), by drilling out the blind rivets (22)

and removing washers (23).

(2) Nose landing gear leg installation:

(a) Before assembly of the nose landing gear, check the outer surface

of the nose landing gear for any cracks and corrosion. Check
the rubber absorber (4, Fig. 32-9) for damage.

(b) As necessary, install the carbon fork and the braking plate:

•

Install the carbon fork (18) on the landing strut (1), using bolts (19),

washer plate (20), washers (15) and the nuts (16).

•

Install the braking plate (21) on the landing strut tab, by drilling

4 holes

ø4 in the braking plate (21) referring to landing strut tab

holes. Put the washers (23) on blind rivets (22) and connect
the braking plate (21) with the landing strut tab using the hand
riveting tool.

(d) Insert the guiding wheel axle (5), install the guiding wheels (6)

and lock them with circlips (24).

(e) Lubricate the rubber absorber (4) with vaseline and slide it into

the upper support assembly (2).

(f)

Slide the landing strut (1) into the upper support assembly (2)
and push it into the lower support (3).

NOTE

It is necessary use greater force.

(g) Put the damping plate (11) between the guiding wheels (6) and

the lower support (3).

(h) Apply Loctite 243 on the bolt (9) thread, screw the bolt (9) into

the sliding bearing (7).

Effectivity:

ALL

04. 07. 2019

LANDING GEAR

(i)

Put the bronze bushings (8) on the landing strut (1) with the rear sliding
bearing (7).

NOTE

Allen head bolt (9) must fit into the gap between the bronze
bushings (8).

(j)

Connect the stirrup (27) with beams (28) using bolts (31), washers (15)
and spit pins (33).

(k) Install the stirrup (27) with beams (28) on the lower support (3).

(l)

Connect the rear sliding bearing (7) with the lower support (3), using
bolts (14), washers (15) and nuts (16) (do not tighten it).

(m) Connect the front sliding bearing with the rear sliding bearing (7) using

bolts (13), washers (15) and nuts (16) (do not tighten it).

(n) Connect the front sliding bearing (7) with the lower support (3) using

bolts (14), washers (15) and nuts (16).

(o) Tighten all nuts fastening upper and lower supports (2; 3) (see 2.D.(2));

tighten

all

nuts

(16)

the

lower

support

(3),

apply

Loctite 243 on the bolts (9) threads and tighten the bolts (9).

(p) Check free movement of the landing strut (1).

(q) At one end of the rubber ropes (12) make loops

ø20 mm and secure it

with lock wire; seal the ends.

(r)

Slide the rubber ropes (12) on the tube (10), put them (10; 12) into
the lower support (3) and lock with split pins (17).

(s) Stretch the rubber ropes (12) (see Fig. 32-10) with force

100 N - 110 N, secure the ends with lock wire; cut and seal the ends.

CAUTION

ENSURE THAT THE FORCE IS DISTRIBUTED EVENLY ON
FULL LENGTH OF THE RUBBER ROPES (12).

(t)

Install the tube (26, Fig. 32-9) on the landing strut (1) using bolts (25),
washers (15).

(u) Install the springs (29) and bolts (32) on the beams (28); equally screw

the bolts (32) so that the springs are tensioned; secure the bolts
with nuts (30).

(v) Connect the nose gear push rods with nose gear levers

(Chapter 27-20).

(w) Install the engine cowlings (Chapter 71-10).

(x) Install the nose wheel (see 2.B.(2)).

NOSE GEAR

LANDING GEAR

(y) Carry out a test and check:

•

That parts are secured with split pins and circlips.

•

If all bolt connections are tight.

•

Plays.

•

Free movement, rotation and damping of the nose landing gear.

•

If the braking plate is braking the wheel.

•

That the rubber ropes are secured with lock wire.

•

Tire pressure (200 kPa).

•

That no foreign objects remain in the aircraft.

(3) Nose landing gear inspection / check

In the following table the permissible plays for nose landing gear attachment
are shown. These values should not be exceeded in operation.

SYSTEM

PROCEDURE TO FIND
A PLAY

PROCEDURE
TO REMEDY A
PLAY

MAX.

PRODUCT.

PLAY

MAX.

OPERATING

PLAY

Nose
landing
gear

Lift the aircraft. Move the
nose wheel forward and
backward to find possible
plays.

Replace the
bushings of the
upper and lower
support.

1 mm /

0.039 in

3 mm /

0.118 in

Tab. 32-8 Maximum Permissible Plays

Effectivity:

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LANDING GEAR

Fig. 32-9 Nose Landing Gear Leg Removal / Installation (page 1 of 2)

NOSE GEAR

LANDING GEAR

– Landing strut

– Bolt M6 x 80

– Bolt M6 x 16

– Upper support

assembly

– Bolt M6 x 20

– Tube

– Lower support

– Washer ø6.4 x 12 x 1.6 27 – Stirrup

– Rubber absorber

– Self-locking nut M6

– Beam

– Guiding wheel axle

– Split pin ø2 x 32

– Spring

– Guiding wheels

– Carbon fork

– Nut M4

– Sliding bearing

– Bolt M6x28

– Bolt

– Bronze bushing

– Washer plate

– Allen head bolt M4 x 20

– Allen head bolt M4 x 5 21 – Brake plate

– Split pin ø2 x 16

– Tube

– Blind rivet ø4 x 20

– Washer ø6.1 x 12 x 0.5

– Damping plate

– Washer ø4.3 x 12 x 1

– Rubber rope

– Circlip ø10

Fig. 32-9 Nose Landing Gear Leg Removal / Installation (page 2 of 2)

Effectivity:

ALL

04. 07. 2019

LANDING GEAR

Fig. 32-10 Method of Turning the Rubber Rope

NOSE GEAR

LANDING GEAR

Nose landing gear leg supports

Type of maintenance:

Heavy

Personnel qualification:

Independent certifying staff qualified in accordance

with Part-66 or higher.

Recommended tools, materials, persons and documentation:

ITEM

QUANTITY

Wrench 10

2 pcs

Wrench 8

1 pc

Loctite 243

Persons

Tab. 32-9 Recommended tools, materials, persons and documentation

(1) Nose landing gear leg supports removal:

(a) Remove the nose landing gear leg (see 2.C.(1)).

(a) Remove the lower support (3, Fig. 32-11), by unscrewing the nuts (8),

removing the washers (9; 10) and bolts (6).

(b) Remove the upper support assembly (1), by unscrewing the nuts (8),

removing the washers (9; 10) and bolts (7).

(5) and removing the bushing (4).

(2) Nose landing gear leg supports installation:

(d) Complete the upper support assembly (1, Fig. 32-11), by sliding

bushing (4) into the upper support (2), apply Loctite 243 on the bolts
(5) threads and tighten the bolts (5).

(a) Install the upper support assembly (1) on the firewall (11), using

the bolts (7) and washers (9; 10), slightly screw the nuts (8) in.

NOTE

Nuts will be tightened after assembly of the landing strut.

(b) Install the lower support (3) on the firewall, using bolts (6), washers

(9; 10) and nuts (8).

(d) Tighten the nuts (8) fastening the upper and lower supports (2; 3).

Effectivity:

ALL

04. 07. 2019

LANDING GEAR

Fig. 32-11 Nose Landing Gear Leg Supports Removal / Installation (page 1 of 2)

NOSE GEAR

LANDING GEAR

– Upper support assembly

– Bolt M6 x 28

– Upper support

– Self-locking nut M6

– Lower support

– Washer ø6.4 x 18 x 1.6

– Bushing

– Washer ø6.4 x 12 x 1.6

– Bolt M5 x 5

For information:

– Bolt M6 x 26

– Firewall

Fig. 32-11 Nose Landing Gear Leg Supports Removal / Installation (page 2 of 2)

WHEELS AND BRAKES

LANDING GEAR

32-40 WHEELS AND BRAKES

1. DESCRIPTION

This chapter describes the wheels and brake system and their operation.

The main landing gear is equipped with an aluminium Beringer wheel discs
(1, Fig. 32-12) with tubeless tires 15x6.00-6 (2). The wheel discs consist of split rim
with two ball bearings. The main wheels are equipped with hydraulic brakes.

The  nose  landing  gear  is  equipped  with  an  aluminium  Beringer  wheel  disc  (3)
with  tubeless  tire  13x5.00-6  (4).  The  wheel  disc  consists  of  split  rim  with  two  ball
bearings.

The main gear wheels are equipped with Beringer hydraulic brakes which are
controlled by the brake lever (10) located on the central console. The brake lever acts
through the push rod and lever directly onto the master cylinder (7) located
in the central console. The brake fluid reservoir (9) and assembled pressure limiter (8)
are located under the left seat. Master cylinder is connected with the pressure limiter
and both brake calipers (5) by hydraulic hoses (11).

Brake discs (6) are inserted into to the shaped wheel rim and locked by a wire.
Calipers (5) are attached to the wheel axles.

The brakes have two positions using grooves at the slotted link: parking brake
and maximum braking.

Parking brake operation:
– To apply parking braking, move brake lever backward to

PARK

position.

– To release parking braking, unlatch the brake lever and release fully forward.
Maximum braking operation:
– To apply the maximum braking, move the brake lever fully backward to

MAX

position.

– To release maximum braking, unlatch the brake lever and release fully forward.
Scheme of the brake system is shown in Fig. 32-13.

Only brake fluid of DOT-4 (meets classification J1703c) should be used for the brake
system (type for medium hard or hard operation). In general, the certified automobile
brake fluid meets the requirements. Brake fluid refilling is necessary when
the efficiency of the brake system becomes low due to a fluid leak. The brake system
is fed from the brake fluid reservoir located under the pilot seat.

The brake fluid gets thick during aircraft operation and absorbs air humidity. This is
the most important condition, which causes brake system failures. It is not possible
to determine exactly when it occurs.

Information about the brake fluid used by the manufacturer is recorded on a placard
at the firewall in the engine compartment.

Effectivity:

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LANDING GEAR

– Main wheel disc

– Master cylinder

– Main wheel tire

– Pressure limiter

– Nose wheel disc

– Brake fluid reservoir

– Nose wheel tire

– Brake lever

– Brake caliper

– Hose

– Brake disc

Fig. 32-12 Wheels and Brakes

WHEELS AND BRAKES

LANDING GEAR

– Brake fluid reservoir

– Pressure limiter

– Master cylinder

– Brake caliper

– Brake lever

Fig. 32-13 Brake System Scheme

Effectivity:

ALL

04. 07. 2019

LANDING GEAR

2. MAINTENANCE PRACTICES

All wheels (with tires fitted) must be balanced before the installation. If a new tire is
installed, the wheel must be re-balanced (with the tire fitted) before the installation.
Unbalanced wheels can cause vibration to the landing gear.

Main wheel

Type of maintenance:

Line

Personnel qualification:

Independent certifying staff qualified in accordance

with Part-66 or higher.

Recommended tools, materials, persons and documentation:

ITEM

QUANTITY

Hex key 5

1 pc

Beringer jig

1 pc

Circlip pliers

1 pc

O ring

2 pcs

Loctite 243

Persons

Beringer documentation- Procedure to change brake pads on
2 piston caliper ref: EA-01

Tab. 32-10 Recommended tools, materials, persons and documentation

(1) Main wheel tire replacement:

(a) Remove the main wheel (Chapter 32-10).

(b) Deflate the tire to zero pressure.

(d) Unscrew the bolts (5) and disassemble discs (2; 3).

(e) Remove the O-ring (4).

(f)

Before assembly of the wheel, thoroughly clean the discs and tires
on contact surfaces.

(g) Press the tire (1) using the Beringer jig (Fig. 32-15).

(h) Install the new O-rings (4) and discs (2; 3).

CAUTION

A NEW O-RING HAS TO BE INSTALLED AT EACH TIRE
CHANGE.

WHEELS AND BRAKES

LANDING GEAR

(i)

Apply Loctite 243 on the bolts (5) threads and tighten the bolts (5)
at torque moment 10 Nm, in order acc. to Fig. 32-15; make sure that
the assembled parts are sealed well.

(j)

Inflate the tire to the appropriate pressure 250 kPa.

(k) After 24 hours check that the air leakage is not more than 10%.

(l)

Inflate the tire to the appropriate pressure.

(2) Main wheel bearings replacement:

(a) Remove the main wheel (Chapter 32-10).

(b) Deflate the tire to zero pressure.

(d) Unscrew the bolts (5) and disassemble the discs (2; 3).

(e) Remove the O-ring (4).

(f)

Use Circlip pliers to remove the circlips (8; 9) and pull out
the bearings (6; 7).

(g) Slide in the new bearings (6; 7) and secure with circlips (8; 9).

(h) Install the tire (see 2.A.(1)).

Effectivity:

ALL

04. 07. 2019

LANDING GEAR

– Tire

– Circlip

– Inner disc

– Circlip

– Outer disc

– Brake disc

– O-ring

– Clip

– Bolt

– Clip screw

– Bearing

– O-ring

– Bearing

– Valve

Fig. 32-14 Main Wheel

Fig. 32-15 Order of Tightening the Allen Bolts, Beringer Jig

WHEELS AND BRAKES

LANDING GEAR

Nose wheel

Type of maintenance:

Line

Personnel qualification:

Independent certifying staff qualified in accordance

with Part-66 or higher.

Recommended tools, materials, persons and documentation:

ITEM

QUANTITY

Hex key 5

1 pc

Beringer jig

1 pc

Circlip pliers

1 pc

O ring

2 pcs

Loctite 243

Persons

Beringer documentation- Procedure to change brake pads on
2 piston caliper ref: EA-01

Tab. 32-11 Recommended tools, materials, persons and documentation

(1) Nose wheel tire replacement:

(a) Remove the nose wheel (Chapter 32-20).

(b) Deflate the tire to zero pressure.

(d) Unscrew the bolts (5) and disassemble the discs (2; 3).

(e) Remove the O-ring (5).

(f)

Before assembly of the wheel, thoroughly clean the discs and tires
on the contact surfaces.

(g) Press the tire (1) using the Beringer jig (Fig. 32-15).

(h) Install the new O-ring (5) and discs (2; 3).

CAUTION

A NEW O-RINGS MUST BE INSTALLED AT EACH TIRE
CHANGE.

(i)

Apply Loctite 243 on the bolts (4) threads and tighten the bolts (4)
at torque moment 10 Nm, in order acc. to Fig. 32-15; make sure that
the assembled parts are sealed well

(j)

Inflate the tire to appropriate pressure 250 kPa.

(k) After 24 hours check that the air leakage is not more than 10%.

(l)

Inflate the tire to the appropriate pressure.

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