SA421CE
Installation of a Lycoming O-360-A1A or O-360-A1D 180 hp engine or O-360-B1B 168 hp engine and constant speed propeller. Held by Williams Barbara Or Bob, which holds 4 approved modifications in all. Last revised July 20, 1993. System: propeller.
What it applies to
- Kind of product
- Aircraft
- Design holder
- The Cessna Aircraft Company; The Cessna Aircraft Company
- Models
- 170B, 170A
- Type certificates
- A-799, A-799
- On this site
- Cessna 170 2,085 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 22, 2026.