SA4-144
Installation of Pratt & Whitney R-985 engine and conversion of airplane to duster. Held by Conair Aviation LTD (Canada), which holds 7 approved modifications in all. Last revised March 11, 1970. System: engine.
What it applies to
- Kind of product
- Aircraft
- Design holder
- Boeing Airplane Company Wichita Division
- Models
- A75N1 Series
- Type certificate
- A-743
- On this site
- Boeing A75 Stearman Kaydet 979 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.