Models
| Model | Type | Registered | Valid | Built |
|---|---|---|---|---|
| S-1A | Fixed wing single engine | 66 | 66 | 1941-1942 |
| S-1B1 | Fixed wing single engine | 23 | 23 | 1942-1993 |
| S-1A-90F | Fixed wing single engine | 6 | 6 | 1941-1942 |
| S-1A-65F | Fixed wing single engine | 5 | 5 | 1941-1942 |
| S-1B2 | Fixed wing single engine | 3 | 3 | 1974-1977 |
| L-6 | Fixed wing single engine | 3 | 3 | 1943-1943 |
| S-1A-85F | Fixed wing single engine | 1 | 1 | 1941-1941 |
Interstate aircraft in the FAA registry
Interstate Aircraft and Engineering Corporation was a small American aircraft manufacturer in production from April 1937 to 1945, based in El Segundo, California. Today, the Federal Aviation Administration (FAA) registry lists 107 valid registrations under the manufacturer name "INTERSTATE." These data reflect the state of the registry as of 2026-10-16. Every aircraft in this group is a fixed-wing, single-engine, reciprocating aircraft. The fleet is heavily historical, with half of the aircraft built in 1941 or earlier and the remainder constructed up to 1993.
Registered Interstate Aircraft by Model
The vast majority of the fleet consists of the S-1A model. There are 66 registered S-1A aircraft, produced between 1941 and 1942. The S-1B1 is the second most common variant, with 23 aircraft built between 1942 and 1993. Smaller groups include six S-1A-90F models, five S-1A-65F models, three S-1B2 models, and three L-6 models. All listed variants are two-seat aircraft. Geographically, California holds the highest number of registrations with 12, followed by Alaska with 10 and Washington with 8.
Type Certificate Data Sheets and Airworthiness
Of the 107 registered aircraft, 97 hold standard airworthiness certificates, while 4 are classified as experimental. The Type Certificate Data Sheets (TCDS) for the primary models are held by STOL Aviation LLC. TCDS A-737 covers the S-1A, S-1A-90F, and S-1A-65F models. TCDS A-754 covers the S-1B1 and S-1B2 models. Each model page provides specifications and the relevant TCDS, and every aircraft has a registration record by N-number for lookup purposes.
Figures from the FAA registry file as of Oct 16, 2026. Company background: Wikipedia, Interstate Aircraft.