A Block IIF GPS satellite
Mission typeNavigation
OperatorUS Air Force
COSPAR ID2014-026A[1]
SATCAT no.39741[1]
Mission duration12 years (planned)
Spacecraft properties
SpacecraftGPS SVN-67 (IIF-6)
Spacecraft typeGPS Block IIF
Launch mass1,630 kilograms (3,590 lb)[2]
Start of mission
Launch date17 May 2014, 00:03 (2014-05-17UTC00:03Z) UTC
RocketDelta IV-M+(4,2), D365[3]
Launch siteCape Canaveral SLC-37B[3]
Orbital parameters
Reference systemGeocentric
RegimeMedium Earth
Perigee altitude20,443 km (12,703 mi)[4]
Apogee altitude20,474 km (12,722 mi)[4]
Inclination55.04 degrees[4]
Period729.22 minutes[4]
Epoch17 May 2014

USA-251, also known as GPS IIF-6, GPS SVN-67 and NAVSTAR 70, is an American navigation satellite which forms part of the Global Positioning System. It was the sixth of twelve Block IIF satellites to be launched.[2]


Built by Boeing and launched by United Launch Alliance, USA-251 was launched at 00:03 UTC on 17 May 2014, atop a Delta IV carrier rocket, flight number D366, flying in the Medium+(4,2) configuration.[3] The launch took place from Space Launch Complex 37B at the Cape Canaveral Air Force Station,[5] and placed USA-251 directly into medium Earth orbit.[4]


As of 17 May 2014, USA-251 was in an orbit with a perigee of 20,443 kilometers (12,703 mi), an apogee of 20,474 kilometers (12,722 mi), a period of 729.22 minutes, and 55.04 degrees of inclination to the equator.[4] It is used to broadcast the PRN 06 signal, and operates in slot 6 of plane D of the GPS constellation. The satellite has a design life of 15 years and a mass of 1,630 kilograms (3,590 lb). [2] It is currently in service following commissioning on June 10, 2014.[6]


  1. ^ a b "Navstar 70". US National Space Science Data Center. Retrieved 17 May 2014.
  2. ^ a b c Krebs, Gunter. "GPS-2F (Navstar-2F)". Gunter's Space Page. Retrieved 17 May 2014.
  3. ^ a b c McDowell, Jonathan. "Launch Log". Jonathan's Space Page. Retrieved 17 May 2014.
  4. ^ a b c d e f McDowell, Jonathan. "Satellite Catalog". Jonathan's Space Page. Retrieved 17 May 2014.
  5. ^ McDowell, Jonathan. "Launch List". Launch Vehicle Database. Jonathan's Space Page. Retrieved 17 May 2014.
  6. ^ "NOTICE ADVISORY TO NAVSTAR USERS (NANU) 2014049". United States Coast Guard. Retrieved 11 June 2014.