A Brief History of an Aerospace Stress Analyst
Transcription
A Brief History of an Aerospace Stress Analyst
A Brief History of an Aerospace Stress Analyst What’s the life of an aerospace stress analyst like? I could answer that question by telling a lot of stories, but perhaps the best way is to give you a historical retrospective. Summer of 1951: On a summer break from Stanford University, I worked at Douglas Aircraft Company in Santa Monica as a Loftsman, making loft lines for the DC-6 on grass cloth with 8H pencils, ducks and splines. I also married my high school sweetheart that summer, just before turning 19. Farm Security Administration/Office of War Information Black and White Negatives (171,097) Rights Advisory: No known restrictions March of 1952: After a serious auto accident, caused by falling asleep at the wheel while driving down from Palo Alto to Santa Monica to visit my draft board, I started work again at Douglas as a Tool Designer. My first job was to design a weld fixture for a DC-6B aircraft toilet! Harry Truman’s Toilet in his private DC-6 Courtesy of Bob Cromwell (http://cromwell-intl.com/) I took evening extension courses at UCLA in engineering and mathematics, learning analytic geometry among other subjects. As an interesting note, during a course in Physics the instructor who had become quite popular on early day television demonstrating various phenomena, I was thrown out of the class when I laughed at the ridiculousness of the statement he made that the Royal Academy of Sciences in England offered a reward of ten thousand dollars to the first person who could demonstrate a working anti-gravity device, since of course that reward would not nothing compared to what that device would be worth. The dean of the college of engineering intervened and the professor had to apologize to me. But he never let me back in to his lectures and I passed the course without ever having to attend another class! During that time I also became a father at almost 20 years old. January of 1953: I went to work for a small firm doing mathematical calculations using the principles of analytic geometry to determine cam profiles for a multi-head milling machine manufacturing long aircraft aluminum wing spars. We did our calculations on a Marchant calculator that could do square roots by moving the carriage and using a method by repeated mechanical additions and subtractions. We utilized huge Library of Congress issued books that gave us trigonometric values in over 10 decimal places! A big improvement in our analysis efficiency came when we obtained a Friden ASR automatic square root machine! Photo of Friden ASR By Marcin Wichary - Flickr: [1], CC BY 2.0, https://commons.wikimedia.org/w/index.php?curid=19541248 During this period of time, I also worked for a small composites company called Zenith Aircraft Company in El Segundo, California, creating various aircraft components, such as wing tips for the B-47 and B-52 aircraft out of E and S-glass cloth and epoxy and phenolic resins. I learned a lot about how to manufacture and analyze composite structures! NO RESTRICTIONS NO RESTRICTIONS Using the education I received at UCLA in engineering and these experiences, I became a contract stress analyst at the Radioplane Company in Van Nuys working on the XQ-5 drone, a later version of the original XQ-1. Public Domain In March of 1954 I traveled East and became a contract stress engineer for Piasecki Helicopter Company in Philadelphia, Pennsylvania, performing stress analyses of the H12 and H-16B helicopters. Public Domain Then, onto the AVRO Company in Toronto, Canada, performing stress analysis on the CF-105B aircraft. I learned how to analyze honeycomb structures and worked with very knowledgeable engineers who had been imported from the UK. They had been offered what seemed to them to be enormous wages, compared to what they had earned at home, only to find out that the cost of living in Toronto far exceeded what they were used to! CC BY-SA 2.0 File:DSC 6934 - Canadian Pride.jpg Created: 16 August 2008 Subsequently I worked as a consultant at Stewart-Warner in Indianapolis performing vibration analysis and testing on a 600 pound purge gas generator suspended in the aft fuselage of the B-52 aircraft. We shook that prototype to death, and when things fell off and I attempted to do analyses to ascertain the cause and make solutions, they just welded the pieces back on and told me what a great job I was doing! In 1956 I returned to California as a contract stress engineer working on pods and pylons at Rohr Aircraft in San Diego on the Convair 880, Lockheed Electra, Boeing 707, etc. Those were the days of hand analyses without the benefit of computers. I used long spreadsheets to do the calculations for many different load cases, using tried and true methods of analysis. I am not sure we could have done much better today using all our advanced methodology! No restrictions DAL-Convair-880inflight-By San Diego Air & Space Museum CC BY-SA 2.0 File:Boeing 707-138B Qantas Jett Clipper Ella N707JT.jpg Created: 6 January 2012 In mid-1957 Lockheed Missiles and Space Company in Sunnyvale hired me as a stress engineer working on the Polaris missile, where I at first used the IBM 650 Magnetic Drum Data-Processing Machine to solve problems relating to basic loads. Later, I developed one of the first nonlinear dynamic codes for launching of the Polaris missile written in FORTRAN. I was also a member of the group that developed the six degree of freedom trajectory code, based on the German scientists work at Peenemunde, used to control flight dynamics. I utilized the Univac electronic computer, then the direct coupled IBM 7090 and later the IBM 360 for our analyses. During that time. In order to gain convergence of the Newton-Raphson nonlinear numeric computations, I believe that I was the first to utilize and create the terminology “numeric damping,” wherein only a percentage of the indicated solution increment was used during the iteration process, resulting in what appeared to be akin to a damped dynamic displacement solution to a vibration process. By UK Ministry of Defense - defenceimagery.mod.uk, OGL, https://commons.wikimedia.org/w/index.php?curid=26683220 In 1959, while on leave of absence from Lockheed due to a shortage of work and as a consultant to Rucker Corporation in Berkeley, California, I conducted the structural dynamic analysis of the Manned Space Craft Center’s 50 foot arm manrated centrifuge. This analysis served as the treatise for my later PhD thesis (“A Preliminary Study of the Structural Dynamic Behavior of the NASA Manned Spacecraft Center (MSC) Centrifuge,” IBSN: 1-58112-206-3). I utilized Lagrange’s methodology to develop the equations of motion that governed the structural dynamic response of the arm and gondola to driving rotational accelerations, displacements and velocities that simulate what happens to spacecraft during launch and orbit. Public Domain During that period I also worked for a brief period at Hiller Helicopter Company, performing stress analysis on a proposal for the Light Observation Helicopter (LOH) project, a contract eventually won by Hughes. For our calculations we used a Bendix paper-tape enabled computer! Public Domain I continued to work for Lockheed full time and garnered my BS in Mathematics in1961 and my MS in Engineering Mechanics from Stanford in 1965, as a part time graduate student. I continued on as a PhD candidate, but the retirement of my mentor and advisor, Donovan Young (who authored several books with Steven Timoshenko) along with a disagreement with my new advisor, Tom Kane, who disapproved of my thesis on the Manned Spacecraft Centrifuge interrupted that process. Also, doing this period I took a leave of absence from Lockheed to perform structural analysis on the Minuteman missile solid rocket motor for Aerojet General. Our analyses utilized the IBM 704 computer employing principles of consistent deformation as coded in software based on finite difference methodology. CC BY-SA 3.0 File:Minuteman Missile NHS.jpg Created: 25 June 2007 Attribution: Lawrence Livermore National Laboratory During that time I also worked for a division of the United Technology Center in Sunnyvale, California, performing structural and structural dynamic analysis on solid rocket propellant motor cases and solid propellant grains for the Titan IIIC, 120 and 160 inch motors, and the Scout rocket programs. I developed methodology for the stress analysis of filament wound motor cases and other advanced composite structures as well as components utilizing viscoelastic materials. Public Domain Public Domain I also worked on an interesting program that involved protecting our small naval ships that were patrolling the Mekong Delta from enemy projectiles and underwater explosions by armoring the vessels. The enemy was carrying either 100 pounds of high explosives, RPGs or anti-tank rockets on their bicycles and using them to attack our patrol boats. Public Domain AVCO Space Systems Division in Lowell, Massachusetts, made me a job offer I couldn’t refuse and I became the Chief of Structures over six groups of engineers performing structural, thermal, dynamic analyses and tests for the Apollo Command Module heat shield. That AVCO division had grown from a small group that developed the ablative heat shield technology into several thousand workers developing and fabricating the Apollo heat shield. Attribution: James E. Scarborough During that time I authored one of the first computer codes for Component Modal Synthesis and submitted a proposal to NASA for a contract to prepare and implement the NASTRAN finite element software program, eventually won by CSC and MSC. The cancellation of the Apollo program basically ended AVCO’s Space System Division entry into the aerospace environment, and I returned to California where I rejoined Lockheed as Section Head of Basic Loads and Criteria. In the following years I worked for TRW in Redondo Beach and, when my then department head left for Hughes Aircraft Company in Fullerton, California, I joined him there as Section Head of Advanced Research and Development, leading five groups of engineers performing structural, thermal, dynamic analyses and tests on ground support equipment. Among the programs we worked on other than GSE equipment were the development of 100 KW wind turbines, solar cells and high powered batteries. Public Domain File:Mod-2 Wind Turbine Cluster3.jpg Uploaded: 10 December 2008 The next years were occupied with various consulting tasks and in 1976 I was asked by a family friend to assist Kaiser Engineers and Contractors with a consulting task in Jeddah, Saudi Arabia. After losing my 22 year old son in a motorcycle accident, I jumped at the opportunity to mask my grief with a challenging task. Interesting enough, the project was a joint venture of Kaiser Engineers, the Losinger Group of Switzerland and the Binladen Organization (the largest contractor in Saudi Arabia and a friend of the United States at that time). Throughout the next 15 years I mixed doing consulting work for companies such as Hughes Aircraft (B2 radar), TEXTRON (JPL project for active control of large space antennas with UCLA) and Rocketdyne (nonlinear dynamic analyses for the Space Shuttle main engine heat exchanger). Public Domain File:STS122 Atlantis.jpg Created: 7 February 2008 Public Domain One of the major projects my own company (Palmieri Consulting Company) undertook was for Interstate Electronics Company of Anaheim, California, to develop a computer program to predict the dynamic behavior of antennas located on top of a 100 foot high mast situated on the deck of the Trident sub, subject to sub motions, wave states and various submergence depths. Seven employees and I worked on this project for over a year and a half, successfully developing and implementing the software. The computer software utilized transient nonlinear dynamic algorithms and statistical methodology to obtain solutions in the time domain for the highly nonlinear and complex problem. OGL File:Trident Nuclear Submarine HMS Victorious.jpg Created: 4 April 2013 Later I was hired as Director of Marketing for the Credit Suisse, Triad and Lockheed joint venture, headquartered in Geneva, Switzerland , for work in Saudi Arabia and the Arab Emirates, based on my earlier work in that region. I then acted as the Director of Marketing for Marwais International, headquartered in Luxembourg. Marwais International was one of the world’s largest manufacturer of hardened aircraft shelters, building shelters throughout the NATO countries and the Middle-East, capable of withstanding penetration from some of the largest bombs available. Public Domain File:HAS Bruggen.jpg Created: 31 December 1980 In or about 1991 my consulting work for Hughes, both the Space and Radar divisions, dominated my activities, leading me to eventually give up my Palmieri Consulting Company operations and work full time there as a consultant. During that time I worked on a variety of programs, from the Intelsat satellite program at Space & Communications and various projects at the Radar Division under the then department head, Hal Cohen. Later I travelled extensively back and forth to Edinburgh, Scotland, coordinating and leading structural activities for the ASTOR program, and later leading the structural analyses of the E-10A project. Finally, in 2009 I became a Raytheon Engineering Fellow, where I remain today, focused on structural and dynamic analyses for the MAMTED department, under the then leadership of Pat Fitzgerald and later Deborah Patrick. RAF Sentinel R1 ASTOR Aircraft MOD 45155055.jpg OGL Attribution: Photo: Sgt Si Pugsley/MOD GFDL 1.2 File:Delta Air Lines Boeing 767-232 Farnborough 1982 Fitzgerald.jpg Created: 21 September 2011 In 2003 I finally completed courses leading to a Ph.D. in Civil Engineering and authored a thesis based on my earlier work on the Johnson Space Center MSC centrifuge (“A Preliminary Study of the Structural Dynamic Behavior of the NASA Manned Spacecraft Center (MSC) Centrifuge,” ISBN-139781581122060, 2003).The course work, supplemental to my studies at Stanford, was performed online for a college known as Madison University, which later became known as a diploma-mill but wasn’t known to me as such at the time I attended! One of the toughest civil engineering courses I took was one on sanitation. It utilized a textbook about 4 inches thick that weighed about 5 pounds! It is indeed strange that after so many years my studies ended with a course that involved something with which my career in engineering began- a toilet! To summarize: over 60 years experience in the Aerospace Industry, with a diverse background in aerospace manufacturing, assembly, design and analysis methodology. I maintain knowledge of the state-of-the-art in analysis methods and software today and keep current on design and manufacturing processes. During that period of time I have performed analyses and developed methodology for wind powered machines, electronic chasses, racks, PWBs, Ball grid arrays and modules for radar units, spacecraft, space antennas, satellites, concrete, armor and ground penetrating munitions, aircraft, helicopters, UAVs, Space Shuttle, drones, missiles, submarines, ships, launch vehicles, rocket motors, composite structures, - to name what I can think of, offhand. In conclusion, this very diverse variety of projects and programs to which I have been exposed over the years reminds me that engineers are often asked to perform tasks as well as analyses on projects that they could probably never envision. Example: Charles Seim is a bridge engineer who worked on dozens of bridges over the course of his career. But one of his early works was a contemplation of forces in a rather different structure: the strapless evening gown. The paper, entitled "A Stress Analysis of a Strapless Evening Gown," was published in the University of California, Berkeley, Cal Engineering Magazine in 1951, a student publication produced entirely by volunteer engineering students once a month during the school year.