A-91-026
NTSB Safety Recommendation — Aviation
Recommendation text
THE NTSB RECOMMENDS THAT THE FEDERAL AVIATION ADMINISTRATION: NOTIFY OWNERS OF HOMEBUILT AIRPLANES, THE EXPERIMENTAL AIRCRAFT ASSOCIATION, FIELD INSPECTORS, AND HOMEBUILT AIRCRAFT MANUFACTURERS, THROUGH A GENERAL AVIATION AIR WORTHINESS ALERT OR OTHER APPROPRIATE METHOD, ABOUT THE POTENTIAL DANGER OF COMBINING A SENSENICH-MANUFACTURED PROPELLER, BASIC MODEL M-74DM, WITH A LYCOMING 0-320 OR LYCOMING 0-0290-D, -D2 AND -D2B SERIES ENGINE WHEN THE DIAMETER OF THE PROPELLER HAS BEEN REDUCED BELOW 72 INCHES, AND RECOMMEND THAT AIRPLANES HAVING THIS COMBINATION OF PROPELLER AND ENGINE BE REMOVED FROM SERVICE.
In plain language (FlightFinder summary)
The NTSB asked the FAA to alert owners of custom-built aircraft and relevant industry groups about a safety risk involving specific propeller and engine combinations. This warning targets situations where a Sensenich M-74DM propeller is paired with certain Lycoming engines after the propeller has been shortened to less than 72 inches in diameter. The agency recommended that these modified aircraft be taken out of service to prevent potential dangers.
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 Action |
|---|---|
| Mode | Aviation |
| Closed | Oct 4, 1991 |
| NTSB number | SEA90FA030 |
| Addressees | FAA |
External links
NTSB safety recommendations are advisory; addressees are not legally required to adopt them. Source: NTSB CAROL (public domain).