| Tail Number / N-Number | N51904 |
| Manufacturer | BOEING |
| Model | A75N1(PT17) |
| Year Built | 1942 |
| Manufacturer's Serial Number | 75-1733 |
| 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) |
| Engine Manufacturer | CONT MOTOR |
| Engine Model | W670 SERIES |
| Engine Type | Reciprocating |
| Number of Engines | 1 engine |
| Horsepower | 250 hp (187 kW) |
| Average Cruising Speed | 93 miles per hour |
| Type of Registrant | Individual |
| Owner Name | MUIR ALAN J TRUSTEE |
| Street | 3011 MILLSTREAM RD |
| City | MARENGO |
| State | IL |
| Zip Code | 60152-8241 |
| Region | Great Lakes |
| County | McHenry County |
| Country | US |
| Fractional Ownership | No |
| Airworthiness Classification | Standard |
| Airworthiness Date | 1990-03-30 |
| Certificate Issue Date | 2008-03-03 |
| Last Action Date | 2022-05-14 |
| Expiration Date | 2029-10-31 |
| Status | Valid Registration |
| Mode S Code | 51502523 |
| Mode S Code Hex | A68553 |