SA637NW
Installation of oil filter kit. Held by Franklin Aircraft Engines INC., which holds 18 approved modifications in all. Last revised May 25, 2022. System: engine.
What it applies to
- Kind of product
- Aircraft
- Design holder
- Maule Aerospace Technology Inc.; Maule Aerospace Technology Inc.; Maule Aerospace Technology Inc.; Maule Aerospace Technology Inc.; Maule Aerospace Technology Inc.; Maule Aerospace Technology Inc.; Maule Aerospace Technology Inc.; Maule Aerospace Technology Inc.; Textron Aviation Inc.; Textron Aviation Inc.; Textron Aviation Inc.; Textron Aviation Inc.; Textron Aviation Inc.; Textron Aviation Inc.; Textron Aviation Inc.; Textron Aviation Inc.; Textron Aviation Inc.; Textron Aviation Inc.; Textron Aviation Inc.; Textron Aviation Inc.; Textron Aviation Inc.; Textron Aviation Inc.; Textron Aviation Inc.; Textron Aviation Inc.; Univair Aircraft Corporation; Univair Aircraft Corporation; Univair Aircraft Corporation; Univair Aircraft Corporation
- Models
- M-4-180C, M-4-180S, M-4-180T, M-4-220, M-4-220C, M-4-220S, M-4-220T, M-5-220C, 172B, 172C, 172D, 172E, 172F (USAF T-41A), 172G, 172H (USAF T-41A), 172I, 172K, 172L, 172M, 175, 175A, 175B, 175C, 170B, 108, 108-1, 108-2, 108-3
- Type certificates
- 3A23, 3A23, 3A23, 3A23, 3A23, 3A23, 3A23, 3A23, 3A12, 3A12, 3A12, 3A12, 3A12, 3A12, 3A12, 3A12, 3A12, 3A12, 3A12, 3A17, 3A17, 3A17, 3A17, A-799, A-767, A-767, A-767, A-767
- On this site
- Cessna 172 Skyhawk 20,669 registered
Maule M-4 207 registered
Maule M-5 364 registered - 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 5, 2026.