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GPS BIIF-4 (PRN 27)

GPS Navigation Satellite (Block IIF) · US Space Force

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GPS BIIF-4 (PRN 27), launched in 2013, is a Block IIF satellite built by Boeing with an expected 12-year design life and enhanced accuracy over the earlier Block IIR generation. IIF satellites carry improved atomic clocks and a more powerful signal structure across all three GPS civilian frequencies — L1, L2C, and L5 — the first GPS generation to broadcast on all three simultaneously from a single spacecraft.

Its orbit

Orbit
Medium Earth Orbita high vantage point, ideal for navigation
Altitude
12,310–12,781 mi (19,810–20,568 km)
Inclination
54.4°
One orbit
12.0 hours2.0 orbits a day
NORAD ID
39166
Int’l designator
2013-023A
Launched
2013

Orbital elements from CelesTrak, as of 22 Sep 2026.

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