BRITISH AEROSPACE (COMMERCIAL AIRCRAFT) LIMITED.

TECHNICAL NEWS SHEET

SERIES: CT (MOTH) N0.21 ISSUE: 1 DATED: 30 JAN, 90

TITLE: UPPER MAINPLANE ROOT END FITTINGS

Aircraft Applicability: DH QUEEN BEE, DH82 and DH82A TIGER MOTH

A case has been reported of cracking in the root end fitting at the upper mainplane rear spar, where the fitting is formed into two bosses which carry the rear attachment bolt. In this particular case the upper boss was cracked right through.

Investigation has shown that the fitting had been in service for a considerable number of years and was generally in a poor condition. The protective stove enamel finish being totally absent in some areas and the metal surface corroded. Furthermore, there was evidence that the joint may have been incorrectly assembled. Metallurgical examination of the defective item revealed that the cracking was caused by fatigue.

We therefore recommend that operators inspect the fittings for condition and signs of cracking at every 50 hour inspection as follows:

a. The fittings, Part Numbers 60603 (Left Hand) and 60604 (Right Hand) should be carefully cleaned and checked for signs of cracking using a dye penetrant method. Particular attention should be paid to the area where the bosses blend into the flat portion as shown in the accompanying sketch.

b. Where the fittings are cracked or any doubt exists as to their condition, they should be changed for new items. Where no signs of cracking can be found, the fittings should be carefully re-protected with epoxy primer and top coat.

c.In all cases it should be ensured that the wing-to-centre section joint is correctly re-assembled with one washer part number 53445. (see accompanying sketch).

Operators should note that in view of the age of the aircraft particular attention should be paid to the condition of all wing fittings and the maintenance of their protective finish during routine inspections.

This Technical News Sheet cancels TNS CT (82) No. 23 issue 1 dated 28 March, 1966.

PREPARED BY PRODUCT SUPPORT DEPARTMENT, CHESTER