AD 81-09-01 ACTIVE

81-09-01 BEECH: Amendment 39-4090. Models C90 (Serial Numbers LJ-642 through LJ-935, LJ-937, and LJ-939 through LJ-941), E90 (Serial Numbers LW-118 through LW-344) and H90 (Military T-44A) (Serial Numbers LL-1 through LL-40 and LL-42 through LL-61) airplanes certificated in any category.

Compliance is required as indicated unless already accomplished.

To prevent malfunction of the landing gear retraction system caused by improper alignment of bearings, accomplish the following:

A) Within the next 100 landings after the effective date of this AD, use procedures specified by Beechcraft Service Instructions (SIs) T-44A-0051 for Model H90 (Military T-44A) or SIs 1160 for Models C90 and E90 to accomplish the following basic actions:

1. Determine whether alignment of bearings in the landing gear retract system is proper as follows:

(a) At each end of the Beech Part Number (P/N) 50-810240 torque shaft, disconnect the bearing inner race from the torque shaft.(b) Using only finger force, attempt to slide each race part way out of the bearing along the torque shaft.

(c) Disregard paragraphs A)1.(d) through A)2.(f) below if the above attempt is successful.

(d) Remove the AN3-31A bolt which attaches the aft end of the gear box to the airframe.

(e) Move the aft end of the gearbox upward or downward until action per paragraph A)1.(b) above is successful.

(f) Find if the previously removed AN3-31A (or a new AN3-32A per paragraph A)2., below) bolt can be installed without deforming holes in the airframe and without moving the gearbox from the position that results in successful action per paragraph A)1.(b), above.

(g) Disregard paragraphs A)2.(a) through A)2.(f) below if action per paragraphs A)1.(b) or A)1.(f) above is successful.

2. Correct any improper alignment of bearings in the landing gear retract system as follows:

(a) If action, in accordance with the applicable SIs, shows this to be necessary, make and install P/N 50-820201-31, -33 and/or -35 shims under bearing supports.

(b) Determine the amount of misalignment between holes for the AN3-31A bolt while the gearbox is positioned per paragraph A)1.(e), above.

(c) Determine or accurately estimate the number of landings during which the P/N 50-810240 torque shaft has been used. Disregard paragraph A)2.(d) below, if one of the following combinations exists:

Hole Misalignment
Number of Landings
1/2 hole or less
less than 5,000
1/2 to 3/4 hole
600 or less
3/4 to 1 hole
200 or less

NOTE: This AD takes precedence over applicable SIs, in that inspection of the torque shaft is required when the combination of 1/2-hole or less misalignment and more than 5,000 landings exists.

(d) Remove the P/N 50-810240 torque shaft from the gearbox and inspect the shaft for a crack, using a dye penetrant method as specified in FAA Advisory Circular AC 43.13-1A. Pay particular attention to circumferential areas on each side of the bearing race that is brazed to the shaft. If the shaft is found to be cracked, replace it with a serviceable P/N 50-810240 torque shaft.

(e) Elongate holes in the airframe as necessary to permit installation of a new AN3-32A bolt in place of the previously removed AN3-31A bolt. Make and install a P/N 50-820201-67 washer plate assembly and a P/N 50-820201-37 plate with the new AN3-32A bolt, as shown in SIs 1160 and T-44A-0051.

(f) Repeat action that is specified by paragraphs A)1.(b) through A)1.(g).

(g) Restore the airplane to an airworthy configuration.

B) Any equivalent method of compliance with this AD must be approved by the Chief, Aircraft Certification Program, Room 238, Terminal Building 2299, Mid-Continent Airport, Wichita, Kansas 67209; telephone (316) 942-4285.

C) For the purpose of complying with this AD, subject to acceptance by the assigned FAA maintenance inspector, the number of landings may be determinedby dividing each airplane's hours' time in service by the operator's fleet average time from takeoff to landing for the airplane type.

This amendment becomes effective April 23, 1981.