SA1649GL
Installation of Sky-Tractor model 500 scavenge oil filter system with P&W model R-985 engines. Held by Airwolf Filter CORP, which holds 7 approved modifications in all. Last revised May 1, 2018. System: engine.
What it applies to
- Kind of product
- Aircraft
- Design holder
- de Havilland Inc. (Canada)
- Models
- L-20A
- Type certificate
- AR-33
- The FAA's record
- On the FAA's site
What an approved modification is
A supplemental type certificate is the FAA's approval of a change to a certified design: a new engine or propeller, avionics, an autopilot, floats, a parachute, a larger fuel tank, an ice-protection kit. The company holding it may sell the kit and the paperwork to owners of the listed models; the modification then becomes part of that aircraft's record. The FAA's list says what was approved and for which models, not how many aircraft carry it.
Source: FAA supplemental type certificates (Dynamic Regulatory System). Register counts from the FAA register of October 8, 2026.