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Landing Gear
AMM

Section 32-20
Nose Landing Gear

1. General
This Section gives you the data for the nose landing gear. It gives you the trouble-shooting and maintenance practices. Refer to Section 32-40 for the data for the nose wheel.
2. Description and Operation
Figure 1 shows the nose landing gear installation. The DA 40 has a fixed nose landing gear with a castering wheel. The nose landing gear strut is a welded tubular-steel component. The aft upper end has a transverse tube which holds the main attachment journal bearings. These journal bearings allow the strut to move only up and down.
Forward and below the attachment bearing is a welded bracket which holds the bottom of an elastomeric spring pack (elastomer pack). The upper end of the elastomer pack attaches to the engine mount.
The forward bottom end of the nose landing gear strut has a near vertical pivot for the nose-wheel fork. This lets the nose wheel castor. Stops limit the castor movement to ±30°.
When the airplane is on the ground, the elastomer pack pushes up against the engine mount. The journal bearings pull down against the front fuselage. When the airplane is flying, the elastomer pack pulls down against the engine mount. And the journal bearing pushes up against the front fuselage.
The journal bearings in the fuselage keep the nose landing gear strut aligned fore and aft. A side load on the nose wheel causes it to castor. The stiffness (steering friction) of the nose-wheel fork pivot can be adjusted with the nose wheel fork mounting screw. This prevents nose wheel shimmy.
Doc # 6.02.01 Page 1
Rev. 4 09 Jan 2003

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AMM

Figure 1: Nose Landing Gear
32-20-00
Landing Gear
AMM

Trouble-Shooting
1. General
Use the data below to trouble-shoot the nose landing gear.
WARNING:  YOU MUST DO A HARD LANDING CHECK AFTER A HARD LANDING. HARD LANDINGS CAN CAUSE DAMAGE TO THE STRUCTURE AS WELL AS THE LANDING GEAR.
Trouble  Possible Cause  Repair 
Strut bent.  Hard landing.  Do a hard landing check. Refer to Section 05-50. Replace the strut. 
Nose wheel shimmy.  Steering friction too low.  Adjust the nose wheel fork mounting screw. 

Doc # 6.02.01 Page 101
Rev. 4 09 Jan 2003

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AMM

Intentionally left blank
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Landing Gear
AMM

Maintenance Practices
1. General
These maintenance practices tell you how to remove, install and adjust the nose landing gear. Refer to the manufacturer for further data.
2. Remove/Install the Nose Landing Gear Strut
A. Equipment
Item  Quantity  Part Number 
Padded trestles  1  Commercial. 
Weight and strap  1  Commercial. 

B. Remove the Nose Landing Gear Strut
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Detail Steps/Work Items  Key Items 
(1)  Use weights to hold the rear fuselage down with the nose wheel clear of the ground.  Use a strap around the fuselage. 
(2)  Put a padded trestle under the front fuselage just aft of the nose gear mounting. 
(3)  Remove the engine cowling.  Refer to Section 71-10 or 71-11. 
(4)  Remove the strut fairing (if installed): S Remove the bolts, nuts and washers at the trailing edge. S Remove the bolts, nuts and washers from the support bracket at the forward bottom side of the cover. S Move the strut fairing clear of the airplane.  Optional, see O.M 40-105. 
(5)  Disconnect the elastomer pack from the engine mount.  Refer to Figure 1. 
(6)  Remove the lock bolt from the journal bearing.  Refer to Figure 1. 
(7)  Compress the journal bearing unit inwards. 
　
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本文鏈接地址：鉆石40飛機維護手冊 DA 40 SERIES AMM 3(78)