A-01-042
NTSB Safety Recommendation — Aviation
Recommendation text
TO THE FEDERAL AVIATION ADMINISTRATION: Require the Boeing Commercial Airplane Group to revise the end play check procedure for the horizontal stabilizer trim system of Douglas DC-9, McDonnell Douglas MD-80/90, and Boeing 717 series airplanes to minimize the probability of measurement error and conduct a study to empirically validate the revised procedure against an appropriate physical standard of actual acme screw and acme nut wear. This study should also establish that the procedure produces a measurement that is reliable when conducted on-wing.
In plain language (FlightFinder summary)
The Federal Aviation Administration is asked to require Boeing Commercial Airplane Group to revise the end play check procedure for the horizontal stabilizer trim system on Douglas DC-9, McDonnell Douglas MD-80/90, and Boeing 717 series airplanes, aiming to reduce the chance of measurement error. Additionally, Boeing must conduct a study to empirically validate the revised procedure against a physical standard for acme screw and acme nut wear, and ensure that the procedure produces reliable measurements when performed on-wing.
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 | Jul 21, 2009 |
| NTSB number | DCA00MA023 |
| Addressees | FAA |
External links
NTSB safety recommendations are advisory; addressees are not legally required to adopt them. Source: NTSB CAROL (public domain).