A-98-031

NTSB Safety Recommendation — Aviation

Recommendation text

THE NTSB RECOMMENDS THAT THE FAA: CONDUCT A CRITICAL DESIGN REVIEW OF CF6-50-80 SERIES HIGH-PRESSURE COMPRESSOR STAGE 3-9 SPOOLS TO ASSESS THE OVERALL SAFETY & SOUNDNESS OF THE PART. THE REVIEW SHOULD, AT A MINIMUM, EVALUATE THE FOLLOWING. THE PROPRIETY OF USING TI-6242 TITANIUM ALLOY, INCLUDING THE POSSIBLE SUSCEPTIBILITY OF THIS ALLOY TO THE DEVELOPMENT OF ABERRANT OR UNDESIRABLE CRYSTALLOGRAPHIC ARRANGEMENTS OF ALPHA PHASE & A RESULTING VULNERABILITY TO RAPID CRACKING.

In plain language (FlightFinder summary)

The FAA is asked to perform a critical design review of CF6-50-80 series high-pressure compressor stage 3-9 spools to evaluate their overall safety and soundness. The review must assess the appropriateness of using Ti-6242 titanium alloy, including its potential for developing undesirable crystallographic arrangements of alpha phase that could lead to rapid cracking.

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
ClosedOct 5, 2000
NTSB numberDCA97WA064
AddresseesFAA

External links

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