Frequently Asked Questions

Problems

Concerns

GPS 101

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?

Visit our Address, Route, & Map Problems page for instructions on how to submit map data corrections to the responsible parties. Go there

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?

The GPS Service Outages & Status Reports page provides points of contact for reporting GPS outages, interference, and other anomalies to the government. Go there

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?

Though acquired and operated by the Department of Defense, GPS is a multi-use system owned by the United States Government and paid for by the U.S. taxpayer. The outstanding performance of GPS over decades has earned the confidence of millions of civil and military users worldwide. The management structure and modernization efforts directed by U.S. policy continue this support for multi-user applications. Any misperceptions will be overcome as they have in the past, by a demonstrated record of service and performance to all users. Learn more about GPS governance

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?

As of August 10, 2018, there were a total of 31 operational satellites in the GPS constellation, not including the decommissioned, on-orbit spares. Learn more

Who pays for GPS?

Has the government considered privatizing GPS?

Answers are on our Program Funding page. Go there

Where can I download high-resolution images of the GPS satellites?

Our Image Library contains various high-resolution images that have been released into the public domain. Go there

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