SA4-919
Modified wing. Held by Leo F Smith & CO INC, which holds 2 approved modifications in all. Last revised September 25, 1973. System: airframe structure.
What it applies to
- Kind of product
- Aircraft
- Design holder
- Boeing Airplane Company Wichita Division; Boeing Airplane Company Wichita Division; Boeing Airplane Company Wichita Division; Boeing Airplane Company Wichita Division; Boeing Airplane Company Wichita Division
- Models
- 75 (Army PT-13), B75 (Navy N2S-5), B75N1 (Navy N2S-3), A75N1 Series, A75 Series
- Type certificates
- A-743, A-743, A-743, A-743, A-743
- On this site
- Boeing 75 18 registered
Boeing A75 Stearman Kaydet 979 registered
Boeing B75 Stearman Kaydet 257 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 19, 2026.