pdf Gfa 062an issue 6 Popular

MISCELLANEOUS AIRWORTHINESS INFORMATION - GROB G 109 & G 109 B 

1. FUEL SYSTEM MODIFICATION (S/N 6001-6159). Grob T.M. 817-9 outlines an optional modification to the fuel system to improve fuel flow to the carburettors. A kit can be obtained from the type certificate holder. 2. USE OF UNLEADED FUEL (ALL S/N). Grob T.M. 817-46 describes the procedures to convert the engine for the use of unleaded fuel. The material required can be ordered from the type certificate holder. DEFECTS: 3. SPINNER FAILURE. Hoffmann Propeller pointed out the problem of defects on the spinner backing plate of the VP30-82 spinner. The G 109 has spinner VP30-81 and this problem may not be relevant, but a check for cracks around the screw holes and every 50 hours is recommended. 4. DELAMINATION OF ELEVATOR SPAR AND TOP SKIN (G 109 B) There is a reported incident of the elevator top skin separating from the spar cap, at and either side of the cutout in the spar accessing the trim tab push rod. The cause is considered to be either Grob has cut away the spar web and spar cap to allow the pushrod to clear the structure, thereby weakening the elevator locally or ground impact on the tailwheel may cause bending at the cut out, eventually promoting separation of the top skin and the spar.