| Tail Number / N-Number | N421MU |
| Manufacturer | CESSNA |
| Model | 421C |
| Year Built | 1977 |
| Manufacturer's Serial Number | 421C0248 |
| Aircraft Type | Fixed wing multi engine |
| Category | Land |
| Builder Certification | Type Certificated |
| Number of Seats | 8 seats |
| Weight Class | CLASS 1 (Up to 12,499 pounds gross take off weight) |
| Engine Manufacturer | CONT MOTOR |
| Engine Model | GTSIO-520-L |
| Engine Type | Reciprocating |
| Number of Engines | 2 engines |
| Horsepower per Engine | 375 hp (280 kW) |
| Total Horsepower | 750 hp (560 kW) |
| Average Cruising Speed | 90 miles per hour |
| Type of Registrant | LLC |
| Owner Name | N421MU LLC |
| Street | 725 SW HIGGINS AVE STE C |
| City | MISSOULA |
| State | MT |
| Zip Code | 59803-1420 |
| Region | Northwest Mountain |
| County | Missoula County |
| Country | US |
| Fractional Ownership | No |
| Airworthiness Classification | Standard |
| Airworthiness Date | 2017-03-13 |
| Certificate Issue Date | 2022-04-12 |
| Last Action Date | 2022-04-12 |
| Expiration Date | 2029-04-30 |
| Status | Valid Registration |
| Mode S Code | 51200174 |
| Mode S Code Hex | A5007C |