2011-20-51: First stage reduction sun gears
Emergency order 2011-20-51 is an airworthiness directive. The FAA's subject line: First stage reduction sun gears. It names the Pratt & Whitney Canada PT6A-15AG, Pratt & Whitney Canada PT6A-27, Pratt & Whitney Canada PT6A-28, Pratt & Whitney Canada PT6A-34, Pratt & Whitney Canada PT6A-34AG, Pratt & Whitney Canada PT6A-36, Pratt & Whitney Canada PT6A series engines: about 773 aircraft on the U.S. register today across them, though an order usually covers particular versions or serial numbers rather than every one. System: engine.
What it applies to as the FAA lists it
- Kind of product
- Engine
- Makes
- Pratt & Whitney Canada Corp.
- Models
- PT6A-15AG, PT6A-27, PT6A-28, PT6A-34, PT6A-34AG, PT6A-34B, PT6A-36
- Engine series
- Pratt & Whitney Canada PT6A-15AG 40 aircraft
Pratt & Whitney Canada PT6A-27 31 aircraft
Pratt & Whitney Canada PT6A-28 13 aircraft
Pratt & Whitney Canada PT6A-34 232 aircraft
Pratt & Whitney Canada PT6A-34AG 271 aircraft
Pratt & Whitney Canada PT6A-36 4 aircraft
Pratt & Whitney Canada PT6A series 182 aircraft
Dates and paperwork
- Docket
- Unknown
- Status
- Current
- The FAA's document
- Read the order on the FAA's site
Source: FAA Dynamic Regulatory System, airworthiness directives. The FAA's document is the authority; the register counts are this site's, from the FAA register of October 5, 2026. Connections as data: /graph/directive/2011-20-51.json · aircraft systems.