SA3021SW-D
Mitchell automatic flight system AK500 and AK500FD consisting of Century IV autopilot and Century IV flight director autopilot with optional remote annuciator panel. Held by Century Flight Systems INC, which holds 765 approved modifications in all. Last revised August 1, 1984. System: flight controls.
What it applies to
- Kind of product
- Aircraft
- Design holder
- The New Piper Aircraft Inc.
- Models
- PA-31-325
- Type certificate
- A20SO
- On this site
- Piper PA-31 Navajo and Chieftain 935 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 20, 2026.