A letter to the editor in the Fall 2007 issue of Virginia Tech Magazine by Gil Davis '60 recalled Hokies who had worked on the Apollo-Saturn Program. I was also one of those fortunate persons. I worked for The Boeing Company in Huntsville, Ala. Boeing was a prime contractor to NASA for the first stage of the Saturn V Rocket (S1-C) and for structural dynamic analysis of the complete Apollo-Saturn V launch system, i.e., the combined Saturn V Rocket, Lunar Module (LM), and Apollo Spacecraft Command Module. I worked in the Vehicle Dynamics, Structural Dynamics Group of roughly 10 engineers.

Of course, other groups worked with us to supply basic information such as stiffness data (matrix), mass/load data, flight control/instrumentation data/equations, forcing functions, etc. Our group was responsible for combining this information from Boeing, as well as from the prime contractors of the various rocket stages and other components, to develop a mathematical model of the Apollo-Saturn Launch Vehicle. This math model was used to perform static, dynamic, and stability analyses. We were using a very new engineering tool at that time, the Finite Element Method. Our primary task was to man-rate the first manned flight of the Apollo-Saturn V Vehicle (Apollo 8 or AS-503 C Prime Mission) to verify that the complete vehicle was safe for astronauts. This was a result of the second unmanned flight of the complete vehicle (AS-502) encountering dangerous POGO oscillations. [In this case, pogo oscillations, also commonly known as POGO oscillations, were a longitudinal vibration stemming from the rocket engine. The named was derived because of the similarity between the oscillations and motions of a pogo stick. http://history.nasa.gov/SP-350/ch-3-5.html.]

The POGO phenomena in this case occurred during first stage (S1-C) burn due to coupling between strong structural and propellant line modes, which produced pressure perturbations in the liquid propellant that was converted to thrust oscillations by the F-1 engines. Such a resonant condition can lead to severe structural damage as encountered in earlier liquid-propellant rocket-development flights. Another anomaly occurred during second stage (S-II) burn when two of the five J-2 engines shut down prematurely. Even with these problems, the vehicle was still able to achieve orbit and perform the Apollo Capsule re-entry test and subsequent recovery in the Pacific Ocean. The successful completion of this mission attests to the robust nature of the vehicle design developed under the direction of Wernher von Braun. The analysis proved that the POGO fix (helium accumulators) installed in the outboard LOX lines did uncouple the system, thus preventing the POGO phenomena during first stage (S-1C) burn. The analysis also showed that the amplitude and frequency of oscillations experienced in the command module would be within acceptable limits and that the remaining vehicle would not encounter the detrimental level of POGO oscillations experienced in the AS-502 flight. It is important to note that only a very intense analytical and experimental effort prevented the POGO problem from negatively affecting the timetable for reaching the moon.

Another unique feature of the first manned flight was that a problem with the LM resulted in a LM Can simulator being installed, which prevented a landing on the moon. This is why the mission was referred to as AS-503 C Prime Mission, generally known as Apollo 8. The Apollo 8 mission, which was the first time humans had been outside the control of the Earth's gravitational field, proved that all the orbital calculations were correct, especially those for the trans-lunar trajectory, the mid-course correction procedures, the lunar orbit insertion and re-entry into the earth's atmosphere. The three astronauts on board, Frank Borman, James Lovell, and William Anders, were real pioneers, a courageous trio.

To the best of my knowledge, the media has never fully covered the importance of American astronauts reaching the moon before the Russians. When we landed on the moon, we declared it to be an open heavenly body for anyone to visit. If the Russians, at that time under the leadership of Nikita Khrushchev, had reached the moon first, they would have claimed it for Russia and dared anyone else to land there. In addition, the Russian propaganda machine would have made claims about Russia's ability to watch and control activity on earth as well as claim the superiority of the communistic (socialistic) system over free enterprise/capitalism. The media would have exploited or exaggerated these claims and thus struck fear into the average American, even though scientists and engineers would have known these claims were false. There could have been serious political repercussions. In short, our world would be different today; the course of world history would have been significantly changed if the U.S. had not reached the moon first.

I fully agree with Gil Davis' statement that 30 years ago, we had put together an extremely talented team that could have tackled any technical problem facing this nation, including the energy crisis, but a shortsighted congress threw this opportunity to the wind. The writing was on the wall at that time regarding our nation's long-term energy needs. Many of us were amazed with the political decisions made, even though they were warned about the future problems. If they had had the wisdom to use this unbelievable pool of talent we would not have an energy problem today. This is a fact that should be brought to the attention of Hokies and others who have never had the opportunity to work on such a program.

J. Ronald Winter '64