A-91-129
NTSB Safety Recommendation — Aviation
Recommendation text
THE NTSB RECOMMENDS THAT THE FEDERAL AVIATION ADMINISTRATION: ISSUE AN AIRWORTHINESS DIRECTIVE, APPLICABLE TO ALL GENERAL ELECTRIC CT7 ENGINES, TO REQUIRE AN IMMEDIATE INSPECTION, USING AN FAA APPROVED METHOD, OF ALL P/N 775801 PROPELLER GEARBOX OUTPUT SHAFTS WITH 5,000 FLIGHT HOURS OR MORE AND AN EXPEDITED INSPECTION OF ALL LOWER-TIME SHAFTS. THE AIRWORTHINESS DIRECTIVE SHOULD REQUIRE THAT THE INSPECTION BE REPEATED WITHIN PRESCRIBED INTERVALS TO ENSURE THAT ANY CRACKS THAT DEVELOP ARE DETECTED BEFORE SEPARATION OF THE SHAFT. (URGENT)
In plain language (FlightFinder summary)
The NTSB asks the FAA to issue an airworthiness directive covering all General Electric CT7 engines. The directive would require an immediate inspection, using an FAA-approved method, of all propeller gearbox output shafts (part number 775801) that have accumulated 5,000 flight hours or more, and an expedited inspection of shafts with fewer hours. The directive should also mandate that the inspection be repeated at set intervals to catch any cracks before the shaft fails.
This plain-language summary is written by FlightFinder to explain the recommendation above. It is not the official wording — the verbatim NTSB text is quoted above.
Details
| Status | Closed - Acceptable Alternate Action |
|---|---|
| Mode | Aviation |
| Closed | Sep 20, 1994 |
| NTSB number | NYC92IA035 |
| Addressees | FAA |
External links
NTSB safety recommendations are advisory; addressees are not legally required to adopt them. Source: NTSB CAROL (public domain).