# SDR DL72W972454

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: November 24, 1997
- Submitted: March 26, 2000
- Operation: Air carrier
- Aircraft: [N831L](https://openairdocs.org/aircraft/N831L), registered now
- Make and model: Boeing 727-2Q8
- Registry model: [Boeing 727-2Q8](https://openairdocs.org/model/boeing-727-2q8) (OpenAirDocs)
- Aircraft serial: 21826
- Engine: Pwa JT8D15
- System (JASC): [4980 · APU Exhaust System](https://openairdocs.org/jasc/4980)
- Part: Exhaust Pipe
- Part number: 38500891
- Condition: Cracked
- Location: Mlg Ww
- Part time: 29,279 hours
- Stage of operation: IN
- Nature of condition: O
- Precautionary procedure: K
- FAA source: FAA Service Difficulty Reporting System (https://sdrs.faa.gov/)
- Page: https://openairdocs.org/sdr/DL72W972454

## Discrepancy

WHILE PERFORMING A POST-REMOVAL INSPECTION OF A GTCP85-98CK APU EXHAUST PIPE (3850089-1), THREE INCH CRACKS WERE NOTED ON EACH MOUNTING FLANGE (TWO CRACKS TOTAL).  CAUSE FOR CRACKS IS UNKNOWN.  EXHAUST PIPE WAS MODIFIED BY ALLIED-    SIGNAL TO SATISFY REQUIREMENTS OF EO 4-69905-3AD (AD 95-07- 03).  THE AD REQUIRED THE INSTALLATION OF AN EXHAUST HUB FOR IMPROVED CONTAINMENT CAPABILITY IN CASE OF T-WHEEL FAILURE.  TIME SINCE LAST SVI FOR APU:  813 HOURS.  EXHAUST PIPE IS   SUBJECT TO REPAIR OR REPLACEMENT BY ALLIEDSIGNAL.

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