A-91-047
NTSB Safety Recommendation — Aviation
Recommendation text
THE NTSB RECOMMENDS THAT THE FEDERAL AVIATION ADMINISTRATION: PENDING COMPLETION OF A CERTIFICATION REVIEW OF THE THRUST REVERSER SYSTEM, ESTABLISH OPERATIONAL PROCEDURES TO BE FOLLOWED UPON ILLUMINATION OF THE REVERSE ISOLATION CAUTION LIGHT (REV ISLN) THAT WILL ENHANCE THE CONTROLLABILITY OF THE PW4000 POWERED BOEING 767 SHOULD A SECONDARY FAILURE RESULT IN THE IN-FLIGHT DEPLOYMENT OF A THRUST REVERSER. ACTIONS SHOULD BE TAKEN TO ACHIEVE AN APPROPRIATE COMBINATION OF AIRSPEED, ALTITUDE AND THRUST SETTINGS THAT WILL MINIMIZE CONTROL DIFFICULTIES IN THE EVENT THAT THE REVERSER SUBSEQUENTLY DEPLOYS. ALSO CONSIDER THE INCLUSION OF A PROCEDURE TO PULL THE FIRE HANDLE IF THIS OCCURS. IN LIEU OF IMPLEMENTATION OF REVISED OPERATIONAL PROCEDURES, OPERATORS MAY BE DIRECTED TO DEACTIVATE THRUST REVERSERS UNTIL THE CERTIFICATION REVIEW IS COMPLETED AND THE RELIABILITY OF THE SYSTEM CAN BE ADEQUATELY ASSURED. (URGENT)
In plain language (FlightFinder summary)
The NTSB asks the Federal Aviation Administration to develop operational procedures for PW4000-powered Boeing 767 aircraft when the Reverse Isolation caution light (REV ISLN) illuminates, to improve controllability if a secondary failure causes an in-flight thrust reverser deployment. These procedures should specify airspeed, altitude, and thrust settings to minimize control difficulties, and include pulling the fire handle if deployment occurs. As an alternative, the FAA may direct operators to deactivate the thrust reversers until a certification review of the system is completed and its reliability is assured.
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 | May 5, 1992 |
| NTSB number | DCA91RA037 |
| Addressees | FAA |
External links
NTSB safety recommendations are advisory; addressees are not legally required to adopt them. Source: NTSB CAROL (public domain).