| Tail Number / N-Number | N990JM |
| Manufacturer | BEECH |
| Model | 65-A90-1 |
| Year Built | 1966 |
| Manufacturer's Serial Number | LM-17 |
| Aircraft Type | Fixed wing multi engine |
| Category | Land |
| Builder Certification | Type Certificated |
| Number of Seats | 9 seats |
| Weight Class | CLASS 1 (Up to 12,499 pounds gross take off weight) |
| Engine Manufacturer | P&W CANADA |
| Engine Model | PT6A-20 |
| Engine Type | Turbo-prop |
| Number of Engines | 2 engines |
| Horsepower per Engine | 550 hp (410 kW) |
| Total Horsepower | 1,100 hp (821 kW) |
| Type of Registrant | Government |
| Owner Name | COUNTY OF GALVESTON |
| Street | 5115 HWY 3 |
| City | DICKINSON |
| State | TX |
| Zip Code | 77539 |
| Region | Southwestern |
| County | Galveston County |
| Country | US |
| Fractional Ownership | No |
| Airworthiness Classification | Multiple |
| Airworthiness Date | 2009-07-31 |
| Certificate Issue Date | 2018-09-10 |
| Last Action Date | 2021-04-27 |
| Expiration Date | 2028-09-30 |
| Status | Valid Registration |
| Mode S Code | 53351567 |
| Mode S Code Hex | ADD377 |