Frequently Asked Questions
Problems
- GPS devices show my home/business in the wrong place or give bad route directions. What should I do?
- GPS devices are routing traffic through my neighborhood. What should I do?
- I lost my mobile phone/device. Can GPS help me find it?
- How do I check for and report GPS service outages?
Concerns
- NEW Is the COVID-19 outbreak affecting GPS operations?
- Are GPS jamming devices legal?
- How vulnerable is GPS to malicious jamming? Could a terrorist with a GPS jammer cause airplanes to crash?
- Is it true the Air Force doesn't want to use GPS in the future because of its vulnerabilities?
- Is GPS under U.S. military control?
- Has the United States ever turned off GPS for military purposes?
- Will the United States ever reactivate Selective Availability?
GPS 101
- How does GPS work?
- How accurate is GPS?
- Is military GPS more accurate than civilian GPS?
- How many satellites are in the GPS constellation?
- Who pays for GPS?
- Has the government considered privatizing GPS?
- Where can I download high-resolution images of the GPS satellites?
GPS devices show my home/business in the wrong place. What should I do?
GPS devices are routing traffic through my neighborhood. What should I do?
I lost my mobile phone/device. Can GPS help me find it?
We recommend you contact your wireless carrier. They may be able to track down your phone/device using the location technology built into it.
Please be aware that the GPS satellites themselves do not track anything on the ground. They are simply beacons, like lighthouses, broadcasting one-way reference signals. Therefore, the government operators of GPS cannot locate your phone/device.
How do I check for and report GPS service outages?
NEW Is the COVID-19 outbreak affecting GPS operations?
No. GPS remains fully operational and continuously available to the world. Please see the following statements from the U.S. Space Force:
- May 7, 2020: 2nd SOPS conducts training, adapts to COVID-19 (spaceforce.mil)
- April 8, 2020: U.S. Space Force meeting mission demands despite coronavirus adjustments (spaceforce.mil)
- March 31, 2020: Space Force accepts control of GPS III satellite amidst global pandemic (af.mil)
- March 28, 2020: Space missions support whole-of-government approach during COVID-19 pandemic (spaceforce.mil)
- March 20, 2020: Schriever stays operational despite COVID-19 (spaceforce.mil)
Are GPS jamming devices legal?
No. Jammers are illegal to market, sell, or use in the United States. Learn more
How vulnerable is GPS to malicious jamming? Could a terrorist with a GPS jammer cause airplanes to crash?
Like all radio-based services, GPS is subject to interference from both natural and human-made sources. A GPS unit can lose reception in the presence of devices designed for intentional radio jamming. Solar flares can also disrupt GPS equipment. For this reason, the U.S. government strongly encourages all GPS users to maintain backup/alternative positioning, navigation, and timing capabilities. In addition, the government is currently fielding new GPS signals that are more resistant to interference.
Commercial aircraft that use GPS are required to maintain alternative means of navigation. If intentional jamming were directed against aircraft, the pilots would revert to other sensors and ground-based navigation aids. Air traffic control would continue to provide surveillance services and ensure aircraft separation.
Is it true the Air Force doesn't want to use GPS in the future because of its vulnerabilities?
The Air Force is fully committed to continuing its operation and use of GPS in the future. The ongoing GPS modernization program will enhance the jam resistance of the military GPS service, making it more robust. At the same time, the Department of Defense is making prudent investments in alternative positioning, navigation, and timing (PNT) technologies to supplement GPS in times when satellite services are unavailable. This will ensure that future troops have continuous, uninterrupted access to PNT under the most challenging conditions.
Is GPS under U.S. military control?
Has the United States ever turned off GPS for military purposes?
No. Since it was declared operational in 1995, the Global Positioning System has never been deactivated, despite U.S. involvement in wars, anti-terrorism, and other military activities.
Millions of users around the world have been monitoring and recording real-time GPS performance on a continuous basis since its inception. If the civilian GPS service had ever been interrupted by its operators, the evidence would be obvious and widespread. No such evidence exists.
Will the United States ever reactivate Selective Availability?
The United States has no intent to ever use Selective Availability again. Learn more
How does GPS work?
Our educational poster explains the basic concepts behind satellite navigation. View it
In addition, our Video Messages page includes several videos addressing the topic. Go there
How accurate is GPS?
Is military GPS more accurate than civilian GPS?
Answers are on our GPS Accuracy page. Go there
How many satellites are in the GPS constellation?
Who pays for GPS?
Has the government considered privatizing GPS?
Answers are on our Program Funding page. Go there