ASN Wikibase Occurrence # 356772
This information is added by users of ASN. Neither ASN nor the Flight Safety Foundation are responsible for the completeness or correctness of this information.
If you feel this information is incomplete or incorrect, you can submit corrected information.
| Date: | Thursday 29 August 1996 |
| Time: | 13:30 LT |
| Type: | Cessna 525 CitationJet |
| Owner/operator: | Jetway Flight Corp., Inc |
| Registration: | N123JN |
| MSN: | 525-0046 |
| Total airframe hrs: | 708 hours |
| Engine model: | Williams Intl FJ44-1A |
| Fatalities: | Fatalities: 0 / Occupants: 3 |
| Aircraft damage: | Minor |
| Category: | Serious incident |
| Location: | Milwaukee, WI -
 United States of America
|
| Phase: | En route |
| Nature: | Executive |
| Departure airport: | (KMKE) |
| (KMKE) | |
| Investigating agency: | NTSB |
| Confidence Rating: |  Accident investigation report completed and information captured |
After being cleared to climb from 6,000', the pilot began advancing the throttles to climb power, when he heard a loud bang & noted indications of a #2 engine failure. He secured the #2 engine & made an uneventful landing. Examination of the failed Williams-Rolls FJ44-1A engine revealed it had sustained an uncontained high pressure turbine (HPT) disk blade retention post failure. Examination of the HTP disk (PN 48629) showed that a blade retention post had fractured adjacent to the bottom of the blade slots & that 3 adjacent HPT blades had broken loose. Subsequently, the upper portion of the fuel-oil heat exchanger mount pad was fractured, which resulted in an oil leak. Metallurgical examination revealed the primary failure was the release of a blade retaining lobe just below a fret zone. Creep fatigue was found at the failed blade retaining holes. No evidence of gross overheating was noted. The failed disk was of an 'older' design. As a result of the incident, Williams-Rolls Alert Service Bulletins No. FJ44-A72-30 and -31 were issued to describe a procedure for eddy current inspection (ECI) of the high pressure turbine (HPT) disk blade retention posts to locate possible cracks and to describe a procedure for replacing the existing HPT disks with an advanced-design HPT disk. Also, Airworthiness Directive (AD) 97-01-05 was issued to require initial and recurring ECIs of the HPT disks and for replacement of FJ44-1A HPT disks with improved disks. A more durable fuel-oil mounting pad was being developed for the FJ44-2 engine.
Probable Cause: an uncontained failure of a high pressure turbine disk blade retention post due to fatigue. A factor relating to the incident was: inadequate design of the high pressure turbine disk. Fretting on the leading side of the lobe near the fracture origin may have contributed to premature initiation of the fatigue.
Accident investigation:
 |
|
Sources:
NTSB CHI96IA320
Location
Revision history:
| Date/time | Contributor | Updates |
|---|---|---|
| 13-Mar-2024 10:43 | ASN Update Bot | Added |
Corrections or additions? ... Edit this accident description
The Aviation Safety Network is an exclusive service provided by:
Quick Links:
| ASN Home | Send Correction / Feedback |
| FSF Home | Disclaimer | Copyright |
| Contact Us | Privacy Policy |
| Press / Media |
CONNECT WITH US:
©2024 Flight Safety Foundation