| Tail Number / N-Number | N3721S |
| Manufacturer | BYINGTON SHAIN |
| Model | S-7S |
| Manufacturer's Serial Number | 0995156 |
| Aircraft Type | Fixed wing single engine |
| Category | Land |
| Builder Certification | Not Type Certificated |
| Number of Seats | 2 seats |
| Weight Class | CLASS 1 (Up to 12,499 pounds gross take off weight) |
| Engine Manufacturer | ROTAX |
| Engine Model | 912S |
| Engine Type | 4 Cycle |
| Number of Engines | 1 engine |
| Horsepower | 100 hp (75 kW) |
| Type of Registrant | Individual |
| Owner Name | SILVAN WAYNE C |
| Street | PO BOX 428 |
| City | BIG SANDY |
| State | MT |
| Zip Code | 59520-0428 |
| Region | Northwest Mountain |
| County | Chouteau County |
| Country | US |
| Fractional Ownership | No |
| Airworthiness Classification | Experimental |
| Airworthiness Date | 2007-04-24 |
| Certificate Issue Date | 2019-06-06 |
| Last Action Date | 2022-01-11 |
| Expiration Date | 2029-06-30 |
| Status | Valid Registration |
| Mode S Code | 51036705 |
| Mode S Code Hex | A43DC5 |
Deregistered Aircraft 1 of 3. This aircraft was previously assigned the N-number N3721S.
| Tail Number / N-Number | N3721S |
| Manufacturer | CESSNA |
| Model | 172E |
| Manufacturer's Serial Number | 17250921 |
| Aircraft Type | Fixed wing single engine |
| Category | Land |
| Builder Certification | Type Certificated |
| Number of Seats | 4 seats |
| Weight Class | CLASS 1 (Up to 12,499 pounds gross take off weight) |
| Number of Engines | 1 engine |
| Average Cruising Speed | 105 miles per hour |
| Type of Registrant | Individual |
| Owner Name | YATES ROBERT E |
| Street | P O BOX 665 |
| City | SHELTON |
| State | WA |
| Zip Code | 98584 |
| Region | Northwest Mountain |
| County | Chouteau County |
| Certificate Issue Date | 1969-05-06 |
| Last Status | Valid Registration |
| Cancellation Date | 1973-03-30 |
| Exported To | CANADA |
Deregistered Aircraft 2 of 3. This aircraft was previously assigned the N-number N3721S.
| Tail Number / N-Number | N3721S |
| Manufacturer | BALLOON WORKS |
| Model | FIREFLY 7 |
| Year Built | 1983 |
| Manufacturer's Serial Number | F7-095 |
| Aircraft Type | Balloon |
| Category | Land |
| Builder Certification | Type Certificated |
| Number of Seats | 1 seat |
| Weight Class | CLASS 1 (Up to 12,499 pounds gross take off weight) |
| Engine Manufacturer | NONE |
| Engine Model | NONE |
| Number of Engines | 0 engines |
| Average Cruising Speed | 63 miles per hour |
| Type of Registrant | Individual |
| Owner Name | SALE REPORTED |
| Street | 1024 TAYLOR ST |
| City | N LAS VEGAS |
| State | NV |
| Zip Code | 89030 |
| County | Chouteau County |
| Country | US |
| Airworthiness Classification | Standard |
| Airworthiness Date | 1983-09-19 |
| Last Action Date | 1987-10-08 |
| Last Status | Sale Reported – Canceled |
| Cancellation Date | 2013-02-25 |
Deregistered Aircraft 3 of 3. This aircraft was previously assigned the N-number N3721S.
| Tail Number / N-Number | N3721S |
| Manufacturer | BEECH |
| Model | 77 |
| Year Built | 1980 |
| Manufacturer's Serial Number | WA-218 |
| Aircraft Type | Fixed wing single engine |
| Category | Land |
| Builder Certification | Type Certificated |
| Number of Seats | 2 seats |
| Weight Class | CLASS 1 (Up to 12,499 pounds gross take off weight) |
| Number of Engines | 1 engine |
| Type of Registrant | Corporation |
| Owner Name | ZED AIR INC |
| Street | 301 CARPENTER DR |
| City | HOLLISTER |
| State | CA |
| Zip Code | 95023 |
| Region | Western-Pacific |
| County | Chouteau County |
| Last Status | Valid Registration |
| Cancellation Date | 1980-12-29 |
| Exported To | AUSTRALIA |