Department of Mechanical Engineering Special Seminar

November 15, 2018 @ 12:00 pm – 1:00 pm
106 Latrobe Hall

“The Hexagon KH-9 Spy Satellite, its workings and importance to world peace”

Presented by Mr. Phil Pressel
Retired: United Technologies Corporation

Mr. Pressel will explain how the stereo camera system worked in perfect synchronization with the incredible amount (30 miles of film for each camera) of fast moving film (200 inches per second) linearly and in rotation. This satellite was and still is considered the most complicated satellite ever put in orbit. It was also one of America’s best and most successful spy satellites. It was launched on the Titan IIID or the Titan 34D from Vandenberg Air Force Base.

Mr. Pressel’s presentation will show some photographs that the system took of some Russian assets and of some cities in the US. The Air Force ran all of the launches from Vandenberg AFB and actually ran the program from 1972 when the CIA turned it over to them.

The following is a more detailed list of what Mr. Pressel will discuss:

  • Impact of zero g’s: gravity release deflection, vacuum, temperature changes
  • Outgassing of materials in space
  • Important properties for glass, invar and other materials
  • Heat treatments and machining cycles necessary to maintain CTE (Coefficient of Thermal Expansion) and stability over time for certain materials (invar is important)
  • How to best lock hardware do’s & don’ts, venting
  • Space qualified adhesives, coatings, paints, lubricity
  • Fits and tolerances, match marking
  • Compensating for delta temperature to maintain alignment and focus
  • Preloading to maintain optical positions after launch vibrating loads
  • Use of bearings and motors in space, cleanliness, brinelling
  • Optical error budgets influence on designs (despace, tilt, decentration)
  • Use of flexures in mounting optical components in a kinematic way to prevent bending optical elements

Mr. Phil Pressel retired after over 50 years working in the aerospace industry, of which for 30 years he worked for the Perkin-Elmer Corporation in Danbury, CT (now United Technologies Corporation). He was the project engineer in charge of the design of the stereo cameras for the formerly top secret Hexagon KH-9 spy satellite, the last film-based satellite. He and his wife live in San Diego and keep busy traveling, writing, consulting and doing volunteer work. He is a Holocaust survivor and describes his and his parents’ wartime escape from the Nazis living in hiding in several cities in France in his first book “They Are Still Alive”.

Since the Hexagon program was declassified in September 2011, he has lectured on the Hexagon program to many national technical organizations and museums including the Wright-Patterson Air Force Base Museum in Dayton, Ohio, the Smithsonian Air & Space Museum and the Spy Museum in DC. He is an accomplished public speaker and has been interviewed by numerous publications including the Associated Press, National Public Radio, various newspapers, a CBS TV affiliate in San Diego and online at He was seen on CNN on September 4, 2016, in a one-hour documentary called “Declassified” about the Hexagon Program. Mr. Pressel has written a book, “Meeting the Challenge: the Hexagon KH-9 Reconnaissance Satellite”, on the importance of the Hexagon program to United States security. He also has a blog about Hexagon that can be accessed at

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