| Tail Number / N-Number | N999XS |
| Manufacturer | STOFFEL RICHARD T |
| Model | VANS RV-4 |
| Manufacturer's Serial Number | 3541 |
| Aircraft Type | Fixed wing single engine |
| Category | Land |
| Builder Certification | Not Type Certificated |
| Number of Seats | 2 seats |
| Weight Class | CLASS 1 (Up to 12,499 pounds gross take off weight) |
| Engine Manufacturer | LYCOMING |
| Engine Model | O-360-C1E |
| Engine Type | Reciprocating |
| Number of Engines | 1 engine |
| Horsepower | 180 hp (134 kW) |
| Kit Manufacturer | VANS AIRCRAFT INC |
| Kit Model | RV-4 |
| Type of Registrant | Individual |
| Owner Name | STOFFEL RICHARD T |
| Street | 234 TRAILSIDE DR |
| City | SEQUIM |
| State | WA |
| Zip Code | 98382-7392 |
| Region | Northwest Mountain |
| County | Clallam County |
| Country | US |
| Fractional Ownership | No |
| Airworthiness Classification | Experimental |
| Airworthiness Date | 2009-11-21 |
| Certificate Issue Date | 2022-07-07 |
| Last Action Date | 2022-07-07 |
| Expiration Date | 2029-07-31 |
| Status | Valid Registration |
| Mode S Code | 53373060 |
| Mode S Code Hex | ADF630 |