| Name of Satellite, Alternate Names | INMARSAT 3 F4 |
| Country of Operator/Owner | United Kingdom |
| Operator/Owner | INMARSAT, Ltd. |
| Users | Commercial |
| Purpose | Communications |
| Class of Orbit | GEO |
| Type of Orbit | |
| Longitude of GEO (degrees) | -125.39 |
| Perigee (km) | 35609 |
| Apogee (km) | 35642 |
| Eccentricity | 0.0003928992392042 |
| Inclination (degrees) | 0.06 |
| Period (minutes) | 1427.91 |
| Launch Mass (kg.) | 2066 |
| Dry Mass (kg.) | 860 |
| Power (watts) | |
| Date of Launch | 03-06-1997 |
| Expected Lifetime | 13 yrs. |
| Contractor | Lockheed Martin Commercial Space Systems |
| Country of Contractor | USA |
| Launch Site | Guiana Space Center |
| Launch Vehicle | Ariane 44L |
| COSPAR Number | 1997-027A |
| NORAD Number | 24819 |
| Comments | Broadcasting, business services, mobile communications; demand assigned L-band transponders; Atlantic Ocean region-West. |