A-00-046
NTSB Safety Recommendation — Aviation
Recommendation text
THE NTSB RECOMMENDS THAT THE FAA: PERFORM A FATIGUE EVALUATION/DAMAGE TOLERANCE ANALYSIS OF THE EUROCOPTER BK117 VERTICAL FIN STRUCTURE TO ENSURE THAT THE INSPECTION REQUIREMENTS OF AIRWORTHINESS DIRECTIVE (AD) 98-24-13 ARE ADEQUATE TO DETECT CRACK GROWTH IN THE UNDERLYING AREAS OF THE MODIFIED SPAR AND LEADING-EDGE SKIN AND TO VERIFY THAT THE BK117 VERTICAL FIN SPAR IS NOT SUSCEPTIBLE TO FATIGUE FAILURE BEYOND THOSE AREAS SPECIFICALLY IDENTIFIED BY AD 98-24-13. IF THE SUSCEPTIBILITY IS NOT SO LIMITED OR THE INSPECTION REQUIREMENTS ARE NOT ADEQUATE, THE AD SHOULD BE SUPERSEDED TO ENSURE THAT ALL FATIGUE CRACKS WILL BE DETECTED.
In plain language (FlightFinder summary)
The FAA is asked to perform a fatigue evaluation and damage tolerance analysis of the Eurocopter BK117 vertical fin structure. This is to ensure that the inspection requirements of Airworthiness Directive 98-24-13 are adequate for detecting crack growth in the modified spar and leading-edge skin, and to confirm that the vertical fin spar is not susceptible to fatigue failure beyond the areas specified by that AD. If the inspections are insufficient or the susceptibility is broader, the AD should be superseded to guarantee detection of all fatigue cracks.
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 | Mar 9, 2001 |
| NTSB number | NYC97FA076 |
| Addressees | FAA |
External links
NTSB safety recommendations are advisory; addressees are not legally required to adopt them. Source: NTSB CAROL (public domain).