# USA-251 > American navigation satellite used for GPS **Wikidata**: [Q16894730](https://www.wikidata.org/wiki/Q16894730) **Wikipedia**: [English](https://en.wikipedia.org/wiki/USA-251) **Source**: https://4ort.xyz/entity/usa-251 ## Summary USA‑251 is an American GPS navigation satellite—also known as GPS SVN‑67, GPS IIF‑6, or Navstar 70—launched on 17 May 2014. It operates for the United States Air Force as part of the NAVSTAR Global Positioning System, providing precise positioning, navigation, and timing services worldwide. ## Key Facts - **Launch date:** 17 May 2014 (Delta IV Medium+(4,2) launch)【source】 - **Launch site:** Cape Canaveral Space Launch Complex 37, Florida【source】 - **Operator:** United States Air Force【source】 - **Country of origin:** United States【source】 - **COSPAR ID:** 2014‑026A【source】 - **Spacecraft number (SCN):** 39741 (Wolfram Language code Entity["Satellite","39741"])【source】 - **Satellite class:** GPS satellite (NAVSTAR Global Positioning System)【source】 - **Aliases:** GPS SVN‑67, GPS IIF‑6, Navstar 70【source】 - **Launch vehicle:** Delta IV Medium+(4,2) (a variant of the Delta IV family)【source】 - **Wikidata description:** “American navigation satellite used for GPS”【source】 ## FAQs ### Q: What is USA‑251? A: USA‑251 is a United States‑operated GPS navigation satellite, part of the NAVSTAR system, launched in May 2014 to provide global positioning, navigation, and timing services. ### Q: When and how was USA‑251 launched? A: It was launched on 17 May 2014 aboard a Delta IV Medium+(4,2) rocket from Cape Canaveral Space Launch Complex 37. ### Q: Who operates USA‑251 and what is its purpose? A: The United States Air Force operates USA‑251, and its purpose is to transmit precise GPS signals that enable civilian and military users worldwide to determine their location, speed, and time. ### Q: What are the other names for USA‑251? A: The satellite is also known as GPS SVN‑67, GPS IIF‑6, and Navstar 70. ### Q: What identifiers are associated with USA‑251? A: Its COSPAR ID is 2014‑026A, its Spacecraft Number (SCN) is 39741, and its Wikidata entry is titled “USA‑251.” ## Why It Matters USA‑251 is a critical component of the Global Positioning System, a constellation that underpins modern navigation, telecommunications, and timing infrastructure. By delivering accurate, continuous GPS signals, the satellite supports a vast array of civilian applications—such as smartphone navigation, aviation routing, and disaster response—as well as essential military operations. Its deployment in 2014 helped maintain the robustness and redundancy of the GPS constellation, ensuring uninterrupted service despite the aging of earlier satellites. The reliability of GPS, bolstered by assets like USA‑251, directly influences economic productivity, safety, and national security worldwide, making each satellite’s contribution strategically significant. ## Notable For - **Part of the IIF (Block IIF) series:** USA‑251 is the sixth satellite in the Block IIF upgrade, offering improved signal accuracy and anti‑jamming capabilities. - **Launch on a Delta IV Medium+(4,2):** Utilized a specific Delta IV configuration, highlighting the launch vehicle’s versatility for medium‑class payloads. - **Multiple designations:** Known by three aliases (GPS SVN‑67, GPS IIF‑6, Navstar 70), reflecting its role across different tracking and naming systems. - **High‑precision identifiers:** Assigned a unique COSPAR ID (2014‑026A) and SCN (39741), facilitating precise cataloging and tracking. - **Operated by the U.S. Air Force:** Directly supports U.S. defense and allied navigation needs, reinforcing the satellite’s strategic importance. ## Body ### Overview USA‑251 is a navigation satellite built for the United States’ NAVSTAR Global Positioning System (GPS). It belongs to the GPS satellite class and is operated by the United States Air Force. The satellite’s primary function is to broadcast GPS signals that enable users worldwide to calculate precise position, velocity, and time. ### Launch Details - **Date:** 17 May 2014 - **Vehicle:** Delta IV Medium+(4,2) – a medium‑lift variant of the Delta IV family. - **Site:** Cape Canaveral Space Launch Complex 37 (SLC‑37). - **Significant event:** The rocket launch was recorded as a notable event on the launch date and location. ### Technical Identifiers - **COSPAR ID:** 2014‑026A – the international designator for the launch. - **Spacecraft Number (SCN):** 39741 – used in satellite tracking databases and Wolfram Language. - **Wikidata entry:** Title “USA‑251” with the description “American navigation satellite used for GPS.” - **Freebase ID:** /m/010lygdr – legacy identifier. ### Operational Role - **Operator:** United States Air Force, responsible for command, control, and health monitoring. - **Purpose:** Provides continuous GPS signal coverage, supporting both civilian navigation (e.g., smartphones, maritime, aviation) and military applications (e.g., precision‑guided munitions, troop positioning). - **Country:** United States – the satellite is part of the nation’s strategic space assets. ### Related Entities - **GPS satellite class:** USA‑251 is one of many satellites that constitute the NAVSTAR system. - **Delta IV Medium+(4,2):** The launch vehicle variant used for this mission, also employed for other medium‑class payloads. ### Visual Reference - **Image:** ![Navstar‑2F](https://commons.wikimedia.org/wiki/Special:FilePath/Navstar-2F.jpg) – depicts a typical Block IIF GPS satellite bus. --- *All information above is derived from the provided source material and references.* ## References 1. Jonathan's Space Report