| Tail Number / N-Number | N521ER |
| Manufacturer | CESSNA |
| Model | 172S |
| Year Built | 2001 |
| Manufacturer's Serial Number | 172S8924 |
| 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) |
| Engine Manufacturer | LYCOMING |
| Engine Model | I0360 SER |
| Engine Type | Reciprocating |
| Number of Engines | 1 engine |
| Horsepower | 180 hp (134 kW) |
| Type of Registrant | LLC |
| Owner Name | 521ER LLC |
| Street | C/O TWIN CITIES FLIGHT TRAINING 8891 AIRPORT RD NE A12 |
| City | BLAINE |
| State | MN |
| Zip Code | 55449 |
| Region | Great Lakes |
| County | Hennepin County |
| Country | US |
| Fractional Ownership | No |
| Airworthiness Classification | Standard |
| Airworthiness Date | 2001-08-20 |
| Certificate Issue Date | 2011-08-11 |
| Last Action Date | 2020-08-24 |
| Expiration Date | 2027-08-31 |
| Status | Valid Registration |
| Mode S Code | 51506431 |
| Mode S Code Hex | A68D19 |