AD 76-09-04

76-09-04 HAMBURGER FLUGZEUGBAU GmbH: Amendment 39-2594. Applies to Model HFB-320 Hansa airplanes, S/N 1021 thru 1023, 1026 thru 1028, 1030 thru 1040, 1045, and 1049 thru 1055, certificated in all categories.

Compliance is required as indicated.

To prevent possible abrupt unwanted deflection of nose wheel steering, caused by a disengaged torque coupling, accomplish the following:

(a) Within the next 10 hours time in service after the effective date of this AD, unless already accomplished -

(1) Inspect the nose landing gear steering torque coupling to ensure that it is in the proper engaged position;

(2) Apply paint markings to the shaft (screw head and nut) and housing of the nose landing gear steering torque coupling in accordance with Figure 1 of HFB 320 Hansa Alert Service Bulletin 32-24A dated September 26, 1975, or an FAA-approved equivalent; and

(3) Install an operating limitations placard in full view of the pilot that reads -

"Prior to each takeoff, check for proper nose wheel marking alignment"

NOTE: It is possible that the nose landing gear torque coupling may become overloaded and disengaged if the maximum steering angle is exceeded in maintenance or taxiing. This condition can be detected by an increased resistance felt at the control wheel.

(b) Prior to each takeoff after the paint markings have been applied in accordance with paragraph (a) of this AD, check the markings for proper alignment. This check may be carried out by the pilot.

(c) If improper alignment is detected during a check required by paragraph (b) of this AD, before further flight, repair the nose wheel steering unit.

This amendment becomes effective, May 10, 1976.