A-98-019

NTSB Safety Recommendation — Aviation

Recommendation text

THE NTSB RECOMMENDS THAT THE FAA: REQUIRE THAT ALL HEAVY ROTATING TITANIUM ENGINE COMPONENTS (INCLUDING THE JT8D-200 SERIES FAN HUBS) RECEIVE APPROPRIATE NONDESTRUCTIVE TESTING INSPECTIONS (MULTIPLE INSPECTIONS, IF NEEDED) BASED ON PROBABILITY OF DETECTION DATA AT INTERVALS IN THE COMPONENT'S SERVICE LIFE, SUCH THAT IF A CRACK EXISTS, BUT IS NOT DETECTED DURING THE FIRST INSPECTION, IT WILL RECEIVE A SECOND INSPECTION BEFORE IT CAN PROPAGATE TO FAILURE; ASSUMING THAT A CRACK MAY BEGIN TO PROPAGATE IMMEDIATELY AFTER BEING PUT INTO SERVICE, AS IT DID IN THE 7/6/96, ACCIDENT AT PENSACOLA, FLORIDA, & IN THE 7/19/89, UNITED AIRLINES ACCIDENT AT SIOUX CITY, IOWA. RECOMMENDATIONS A-96-74 & A-96-75 ARE SUPERSEDED BY A-98-19.

In plain language (FlightFinder summary)

The FAA is asked to require that all heavy rotating titanium engine components, including JT8D-200 series fan hubs, receive nondestructive testing inspections—possibly multiple inspections—based on probability of detection data at intervals during the component's service life. The inspections should be designed so that if a crack exists but is missed on the first inspection, a second inspection occurs before the crack can cause failure, acknowledging that a crack may begin propagating immediately after service entry, as seen in two previous accidents.

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 - Unacceptable Action
ModeAviation
ClosedJun 30, 1999
NTSB numberDCA96MA068
AddresseesFAA

External links

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