# SDR 2026FA0000325

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: April 28, 2026
- Submitted: May 7, 2026
- Operation: General aviation
- Aircraft: [N3A](https://openairdocs.org/aircraft/N3A), registered now
- Make and model: Cntrar 101ACENTR
- Aircraft serial: 008
- Aircraft time: 3,938 hours, 2,929 cycles
- Engine: Lyc IO360C1G6
- Engine time: 1,459 hours, 1 cycles
- Propeller: Hofman HOV352F
- System (JASC): [6100 · Propeller System](https://openairdocs.org/jasc/6100)
- Part: Drive Shaft
- Part number: 077221200240
- Part serial: 10348105
- Condition: Deformed
- Location: Rt Engine
- Part time: 1,617 hours, 1,447 cycles
- Stage of operation: IN
- How discovered: V
- Nature of condition: O
- Precautionary procedure: K
- FAA source: FAA Service Difficulty Reporting System (https://sdrs.faa.gov/)
- Page: https://openairdocs.org/sdr/2026FA0000325

## Discrepancy

WHILE CHANGING RT PROPELLER GEARBOX, WHEN REINSTALLING BOLTS WOULD NOT GO BACK INTO DRIVESHAFT HOLES.  WHEN MANUFACTURER (ZEPPELIN) WAS CONTACTED THEY WERE AWARE OF A MANUFACTURING DEFECT WITH CERTAIN SERIAL NUMBER DRIVESHAFTS.  THIS DRIVESHAFT WAS ONE OF THOSE SERIAL NUMBERS THAT THEY IDENTIFIED AS HAVING AN ISSUE. ON INITIAL INSTALL THE BOLT HEAD SMASHED MATERIAL DOWN IN THE HOLES OF THE DRIVESHAFT BOLTS, MAKING THE BOLTS HARD TO REMOVE & TOO HARD, WITHOUT CONCERN, TO INSTALL.

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