A-79-006

NTSB Safety Recommendation — Aviation

Recommendation text

ISSUE AN ALERT BULLETIN WITH THE FOLLOWING PROPOSED WORDING: "A SIMULATED RUNAWAY PITCH TRIM EXERCISE IS SUSPECTED AS A FACTOR IN A RECENT LEARJET ACCIDENT. UNTIL THE RESULTS OF THE ONGOING INVESTIGATION ARE FINAL, IT IS RECOMMENDED THAT ALL OPERATORS OF LEARJETS REVIEW THEIR REQUIREMENT TO PRACTICE A RUNAWAY TRIM. IF PRACTICE RUNAWAY PITCH TRIM EXERCISES ARE DEEMED NECESSARY, IT IS RECOMMENDED THAT THE EXERCISE BE PERFORMED IN A MANNER WHICH WILL NOT ALLOW AN EXCESSIVE NOSEDOWN ATTITUDE OR HIGH AIRSPEEDS TO DEVELOP. INTERVIEWS WITH SOME OPERATORS OF LEARJETS HAVE DISCLOSED THAT RUNAWAY TRIM EXERCISES HAVE RESULTED IN DANGEROUS NOSEDOWN ATTITUDES AT HIGH AIRSPEEDS AND THAT RECOVERY FROM THESE CONDITIONS WAS MARGINAL." (URGENT)

In plain language (FlightFinder summary)

The FAA is asked to issue an urgent notice to Learjet operators regarding a recent accident linked to simulated runaway pitch trim failures. The guidance advises pilots to carefully evaluate whether practicing this specific maneuver is necessary and, if so, to ensure it is done safely without allowing the aircraft to enter dangerous steep dives or excessive speeds. This caution stems from reports that previous training attempts had led to difficult recovery situations due to extreme flight conditions.

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

StatusClosed - Acceptable Action
ModeAviation
ClosedNov 29, 1979
NTSB numberCHI78FA010
AddresseesFAA

External links

NTSB safety recommendations are advisory; addressees are not legally required to adopt them. Source: NTSB CAROL (public domain).