A-90-114
NTSB Safety Recommendation — Aviation
Recommendation text
THE NTSB RECOMMENDS THAT THE FEDERAL AVIATION ADMINISTRATION: REVIEW THE CERTIFICATION DATA FOR THE LTS/LTP-101 TO VERIFY THAT THE VIBRATORY CHARATERISTICS OF THE ENGINE ROTOR DISCS, ROTOR BLADES AND ROTOR SHAFTS ARE NOT DETRIMENTAL TO THE FATIGUE LIVES OF THE COMPONENTS WHEN THE ENGINE IS OPERATED IN ITS NORMAL RANGE OF ROTOR SPEEDS UNDER BOTH STEADY STATE AND TRANSIENT CONDITIONS. IN ADDITION, VERIFY THAT THE FATIGUE LIVES OF ENGINE COMPONENTS ARE NOT ADVERSELY AFFECTED BY THE VIBRATORY CHARACTERISTICS OF THE HELICOPTER.
In plain language (FlightFinder summary)
The NTSB asks the FAA to review certification data for the LTS/LTP-101 engine to confirm that vibration from the engine's rotor discs, blades, and shafts does not harm the fatigue life of those parts when the engine runs at normal speeds, both steady and transient. Additionally, the FAA must verify that the helicopter's own vibrations do not negatively affect the fatigue life of engine components.
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 | Feb 20, 1991 |
| NTSB number | MIA90FA081 |
| Addressees | FAA |
External links
NTSB safety recommendations are advisory; addressees are not legally required to adopt them. Source: NTSB CAROL (public domain).