| Tail Number / N-Number | N21973 |
| Manufacturer | PORTERFIELD |
| Model | CP-50 |
| Year Built | 1939 |
| Manufacturer's Serial Number | 559 |
| 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 | A50 SERIES |
| Engine Type | Reciprocating |
| Number of Engines | 1 engine |
| Horsepower | 50 hp (37 kW) |
| Average Cruising Speed | 76 miles per hour |
| Type of Registrant | Corporation |
| Owner Name | WESTERN ANTIQUE AEROPLANE & AUTOMOBILE MUSEUM |
| Street | 1600 AIR MUSEUM RD |
| City | HOOD RIVER |
| State | OR |
| Zip Code | 97031-9800 |
| Region | Northwest Mountain |
| County | Hood River County |
| Country | US |
| Fractional Ownership | No |
| Airworthiness Classification | Standard |
| Airworthiness Date | 1956-10-22 |
| Certificate Issue Date | 2015-06-02 |
| Last Action Date | 2021-02-01 |
| Expiration Date | 2028-06-30 |
| Status | Valid Registration |
| Mode S Code | 50357132 |
| Mode S Code Hex | A1DE5A |