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GPS Block II F satellite
Recent books about the history of GPS have distorted how the program actually developed. (credit: US Air Force)

GPS origins myths as propounded by Stephen Johnson and Annie Jacobsen

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My first article about GPS was published in The Space Review in 2006 (see “Who invented the Global Positioning System?”, The Space Review, May 22, 2006). Eric Frazier read it in February 2010 and contacted me with questions for a book he was writing about GPS. After some discussion we agreed to join forces and co-wrote GPS Declassified: From Smart Bombs to Smartphones ( This article discusses deficient treatments of the history of GPS in two books that confuse Transit, the first space based navigation system, with GPS, the Global Positioning System, which was developed separately.

Johnson also states that around 1983, the system took on its current name, GPS. This ignores the development of GPS, which is a completely separate system from Transit.

In the fall of 2010, as we were approaching publishers about our narrative book about the history of GPS, my wife gave me a copy of a new book by Steven Johnson, Where Do Good Ideas Come From. Naturally, I looked first at the index for entries on GPS. It had them, but Mr. Johnson’s research proved to be sadly deficient. His book contains gross errors that even a modicum of research would have corrected. For example, on page 186, he states that Korean Air Flight 007 was shot down in 1983 after drifting into Soviet airspace due to faulty ground-based navigational beacons. The far more likely explanation was that the wayward flight path resulted from inputting incorrect coordinates into the inertial navigation.

Johnson covers the origins of Transit, the first satellite based navigational system. He states that after the KAL 007 shoot down, President Reagan declared that satellite based navigation should be a public good open to civilian use. In fact, civilians started using Transit as early as 1967. He also states that around that time, the system took on its current name, the Global Positioning System or GPS. This ignores the development of GPS, which is a completely separate system from Transit. Transit used Doppler techniques, whereas GPS uses the time the signal takes in traveling from the satellite to the receiver to compute the distance between them. With four satellites in sight, three dimensions and time can be computed. The initial GPS system was formulated in 1973 using aspects of the Navy’s Timation and the Air Force’s 621B systems (I argue in GPS Declassified that it predominately came from Timation). Philip J. Klass states in the November 26, 1973, issue of Aviation Week & Space Technology that the system has been renamed the Global Positioning System; this is a decade before Johnson’s date. Thus, Johnson oversimplifies and distorts the story.

His TED talk on the subject repeats these mistakes When I heard his TED talk on NPR, I contacted NPR and the TED organization to correct the story. I received no reply from NPR and got a form letter from the TED organization. Neither organization appeared to be interested in correcting these mistakes.

GPS World Innovation columnist Richard Langley mentioned on a celestial navigation discussion board that “GPS was designed to be used by both the military and the civil community from the get-go.” Harry Sonnemann, twice chair of NAVSEG (Navigation Satellite Executive Steering Group – they were working on a replacement for Transit) in the 1968–1973 time period, said that civilian uses were considered from the beginning, but only the Department of Defense was willing to fund what became GPS.

Steven Johnson may be relatively unknown to readers of The Space Review; however, Annie Jacobsen’s previous books have been criticized at length here (see “Roswell that ends well”, The Space Review, May 31, 2011; and “Review: Operation Paperclip”, June 15, 2015). I recently listened to an interview with her at the Spy Museum. About 27 minutes into the program, she states that GPS was originally a DARPA program. That’s not true, so I scrutinized her new book, The Pentagon’s Brain: An Uncensored History of DARPA, America’s Top Secret Military Research Agency, to see if I could determine the source of her erroneous assertion. On pages 249–250, she makes many incorrect statements:

“DARPA’s pioneering GPS program was called TRANSIT.” As mentioned earlier, Transit was the first satellite based navigation system. GPS refers to a later program begun in 1973. Transit was never called GPS.

“After several failed launches, TRANSIT finally took up residence in space in June 1963. To deny enemy access to this kind of precise targeting information, the system was originally designed with an offset built in, called selective availability (SA).” Selective availability was a degradation of the civilian signal for GPS. It was not used on Transit, which was much less precise.

The sloppy research on GPS is in line with the criticisms of Jacobsen’s earlier books, and calls into question the factual bases for other DARPA projects she discusses.

“In 1973, the Pentagon ordered DARPA to create a single system shared by all the military services.” As I mentioned, she made a similar statement at the Spy Museum. This is incorrect. On April 17, 1973, Deputy Secretary of Defense William P. Clements, Jr., ordered the Air Force to be the executive service for a Joint Program Office (JPO) for the Defense Navigation Satellite System (later called GPS). It was to be a joint Army, Navy, Marine Corps, and Air Force program office. DARPA was not mentioned because it played no role in the 1973 JPO. Later, DARPA funded development of miniaturized GPS receivers, but it did not create the 1973 synthesis of the Navy’s Timation and the Air Force’s 621B programs (this is covered in detail in GPS Declassified). The Decision Coordinating Paper Number 121 (Revised) Defense Navigation Satellite Development Program (June 7, 1973) covers a meeting on the West Coast on June 6 and 7, 1973. There were Navy, Air Force, and Army presentations. DARPA is nowhere mentioned because it was not involved in the process.

Ms. Jacobsen has an endnote for page 250. She appears to have not read this reference very closely, since it correctly states, “TRANSIT is scheduled to be replaced by the DoD Global Positioning System (GPS) which uses different technology, in 1996.” Her assertion that DARPA developed GPS in 1973 is not found in this document, so it’s unclear what the source of this fable was. Perhaps it stems from her confusion of Transit with GPS. There are eighteen references to GPS in the document (not all are to the Global Positioning System), but it nowhere claims that DARPA played a role in its initial formulation in 1973. Many of the references pertain to the dual use of GPS satellites, which carry nuclear detonation detection systems in addition to the navigational instruments. As I mentioned earlier in this article, Klass wrote in Aviation Week in 1973 that the Defense Navigation Satellite System program has been renamed the Global Positioning System.

On page 253, she states that under Secretary of Defense Harold Brown in the Carter Administration, “Global Positioning System technologies were accelerated at whirlwind speeds”. It’s true that the first Block 1 (test) GPS satellites were launched in the Carter Administration. However, in 1979 it cut back GPS from 24 to 18 satellites. This would have limited its accuracy and usefulness. When the Block 2 (operational) satellites were launched beginning in 1989, the decision was made to go back to 24 satellites. Thus, there was no acceleration of GPS under Secretary Brown; rather, there were significant cutbacks in the program.

I have not read the rest of the book, but the sloppy research on GPS is in line with the criticisms of her earlier books, and calls into question the factual bases for other DARPA projects she discusses.

It is very disappointing to encounter such poorly researched misinformation about GPS in popular books vetted by large, established publishers and promulgated by media organizations that consumers trust for accurate histories of the scientific advances that shape modern life.