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‘Flying for GPS’: Memoir of a Pioneer Era — Excerpt

July 1, 2014  - By

Flying-for-GPS-JacobsonFlying for GPS, a chronicle of Len Jacobson’s role in the development and promotion of the Global Positioning System, has just been published.
The book spans a 50-year career, during which Jacobson flew 2.5 million miles as a missionary for GPS and as a developer of user equipment. He kept an extensive log of all of his flights, and it enabled him to recreate in his book much of what happened with GPS during his career, and his impressions of why these events occurred.

Flying for GPS covers the user-equipment evolution from expensive, complex, and voluminous military sets to today’s low-cost chips buried in our cell phones. It traces a system designed primarily for military and civilian aircraft, ships, and land vehicles to an essential utility of everyday life, enabling new businesses, more safety, and the ability to track everything that moves. It is also a memoir written for the GPS community.

The book draws from Jacobson’s GPS experience while working for Hughes Aircraft, Magnavox, Interstate Electronics (IEC), and his own company, Global Systems and Marketing, Inc.

He worked on various assignments from most of the major GPS companies and several small businesses that were trying to find a position in the GPS market. He also participated as an expert witness in many legal cases involving GPS, from patent disputes to accident reconstruction to parolee tracking.

In parallel with the evolution of GPS, the book chronicles the changes in commercial air travel as Jacobson experienced it, from flying on a PanAm 707 in 1963 to an Air France A380 today. The book is available now from www.xlibris.com, Amazon, Barnes & Noble, and soon from ebook outlets.


Len Jacobson.

Len Jacobson.

Excerpt from Flying with GPS

By Len Jacobson

A man in a trench coat borrowed one of our civil GPS Z-sets in late 1979. He couldn’t or wouldn’t say what it would be used for. He suggested that I call over to the Joint Program Office (JPO), and they would verify the validity of the request. A year later I found out what it was all about.

The Z-set had two boxes, a receiver and a panel mounted control/display unit (CDU). We got the receiver back but we never got the CDU. I learned later that the Z-set had been installed in one of the helicopters used in operation Eagle Claw, the failed April 1980 raid to rescue the U.S. Embassy hostages in Iran. I guess the Special Forces were able to recover the Z-set receiver but not the CDU, as the helicopters were all destroyed.

I ran a coverage plot for the day of the raid over Iran, and found four satellites were in view at that time. I also received a copy of an Iranian newspaper that had a big article on GPS in Farsi. I couldn’t read it and I don’t think it mentioned the raid, but there was a diagram of the GPS constellation, so I know the Iranians were very aware of GPS. That mission may have been the very first operational military use of GPS.

Another Covert Role. In September of that same year, a Vela reconnaissance satellite detected a “double flash” that was deemed by many to be evidence of a atmospheric nuclear explosion off of South Africa in the South India Ocean. While many of the details are classified, there is quite a write up about it in Wikipedia, under “Vela Incident.”

This came at a time when the GPS program was in even greater budget peril than normal. The Secretary of the Air Force at that time was trying to zero out the GPS budget, and it looked very likely he would succeed. But along came a procurement for a Nuclear Detonation Detection System payload package to be placed on all future GPS satellites. I believe that saved the GPS program from a premature demise.

I also suspect, as do many others, but cannot prove, that the flash was created by an Israeli nuclear test. If so, one might infer that Israel actually, albeit unwittingly, saved the GPS program from extinction.


Len Jacobson is a retired GPS consultant, having worked in the field since 1968. He is a charter member of the Editorial Advisory Board of GPS World magazine and is also still active in the Institute of Navigation, for which he served as western regional vice president twice and held leadership roles in several of its conferences. He lives in Long Beach, California. Visit his site at www.lenjacobson.com.

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