SA4-128
Engines, propellers, revised nacelles, wheel-well doors, air- speed system, fuel system and elevator seal strips. Held by Staggerwing Museum Foundation INC., which holds 123 approved modifications in all. Last revised October 6, 2006. System: propeller.
What it applies to
- Kind of product
- Aircraft
- Design holder
- Hawker Beechcraft Corporation; Hawker Beechcraft Corporation
- Models
- Army AT-11, C18S
- Type certificates
- A-2-582, A-757
- On this site
- Beechcraft C18 13 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 7, 2026.