646657
CYLINDER HEAD
Specifications
- Part Number
- 646657
- Manufacturer
- —
- ATA ChapterMaintenance system chapter
- 85 — Reciprocating EngineField reports: 85 (100%) — 8 reports
- CapabilitySystem area (hydraulics, avionics, landing gear…)
- Engine Accessories
- Inventory ClassRotable, expendable, or consumable
- Rotable
- Certification
- PMA
- Aircraft Category
- General-Aviation
- Criticality
- Standard
- Life & ShelfTypical service/shelf life — verify against OEM data
- —
Service Reliabilityfrom FAA SDR (Service Difficulty Reports)
67%
Scrap Propensity (SDR-derived)
- SDR reports
- 8
- Replace events
- 4
- Repair events
- 2
- K-code events
- 6
Reporting window 1996-05-24 – 2002-02-18Dominant chapter ATA 85
Directional indicator only. Reflects what operators reported to the FAA when a difficulty was logged — not a fleet-normalized failure rate or a cost-based BER. Use alongside operator-specific data.
Airframe Applicability(4)
Alternate / Related Part Numbers(1)
AEC631397pma replacement
Data Sources(1)
- 2026-03-07
Quick Facts
Airframes4 applicable
Alternates1 found
ClassRotable
CriticalityStandard
CategoryGeneral-Aviation
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