History of Mechanical Integration and Test at Space Park (1984)

In 1984, Rick Wagner was asked to research and write a history of the Mechanical Integration and Test (MIT) Department in the Integration and Test Laboboratory of Space Systems Division of TRW. This is the resulting history that was later incorporated into the MIT Department Assimilation Manual.


The scope of this history is small. This history is not about TRW or about Space Park or about spacecraft or even the history of testing itself. References are made to launches of TRW built spacecraft, but the list is not intended to be complete. For a history of TRW spacecraft, see the Space Logs TRW has published. This history addresses itself primarily to the past of the Mechanical Integration and Test Department, with references to associated organizations, both larger and smaller.

As this history was pieced together from interviews conducted with “old timers” (20 years or more) in integration and test, it is an oral history that has been written down, and contains many gaps and omissions (and, possibly, inaccuracies). Some of the material from interviews was not used, usually because exact dates could not be recalled. I wanted the dates at least to be precise (saying “sometime in the early sixties” didn’t seem quite right). I wish to express my appreciation to all who participated in the preparation of this section, and I invite those whom I might have overlooked as sources to come forward and correct or expand on this history so it may become more complete with time.

Organizing this history was difficult, and to simplify the task, I chose the chronological approach. The date at which a program is mentioned is the start date for that program, although most programs referred to continued for several years.

Richard J. Wagner
8 August 1984


1956: The Guided Missile Research Division of the Ramo-Woolridge Corporation had facilities on El Segundo Boulevard (Building B and C) and on Arbor Vitae (Buildings 1, 3, 4, and 6). There was one High Bay and no bridge crane. The structural test facility consisted of a 15 foot steel cage, still visible today in the “iron pile” behind M1. There was a Model Shop (Building 6) where scale models of missiles and ground support equipment were made. Scale models of the Atlas and Thor boosters and a scale model of the Minuteman Silo were built there.

1957: Ramo-Woolridge was primary contractor on the Ballistic Missile Program with Boeing, Martin, and Convair as subcontractors. The Ramo-Woolridge organization that was to become the current “TWO Electronics and Defense” was Space Technology Laboratories (STL).

1958: Convair wanted the Air Force follow-on contract, but STL got it. It seems the Air Force was having difficulty running their ground support (GS) program. They wanted to have the capability of supporting launches of ICBMs with only military personnel. After several launch failures using military ground crews, Aerospace Corporation was formed to go in and put them back on track. That was called project Golden Ram.

1960: STL launched the Venus Flyby. The Lunar Orbiter nose fairing came off on launch resulting in a mission failure. The role of mechanical development became more important with more ambitious launches.

1962: STL integration and test activities moved to M1 and M2 in Space Park. Bill Sheehan was the manager of Mechanical Integration and Test Department, with about 25 people, 12 of them engineers. Work underway included structural tests on the Orbiting Geophysical Observatory (OGO) and Vela, separation and cold tests on Vela, and mechanical appendage testing on OGO using air bearings on an epoxy floor, a first in the industry.

1963: There was a “propulsion race.” Rocketdyne had all the big engines, but they were having problems with their J2 second stage engine (Apollo). Because of these problems, Rocketdyne chose to concentrate on the J2 so STL got the Lunar Module Descent Engine (LMDE) used for the Apollo Project. The LMDE was a real technical challenge. No one had ever built a 90% throttleable restartable engine before, not to mention the requisite power and burn duration. STL hired people from the Jet Propulsion Laboratory (JPL) and from Aerojet. STL succeeded using an ablative expansion nozzle, boundary layer thermal control, and an innovative bipropellant flow control valve. Important R and D and integration and test activities included careful mechanical linkage and flow control valve characterization, leak and proof pressure testing, injector “paternization” by photograph, precision setting of valves, and live firing in a high altitude test chamber. LMDE work continued to 1969. On July 20, 1969, Neil Armstrong fired the Apollo 10 LMDE for 756.3 seconds, landing his craft on the moon.

Other programs in 1963 included OGO, Vela, and Model 35.

1964: STL became TRW Systems. This year saw the first OGO launch, which was partial failure and led to improved test methods. An instrument boom was to have been deployed by a helical torsion spring at the boom hinge. On orbit, insufficient torque resulted in a partially deployed unlatched condition. The instrument on the boom blocked the view of an earth sensor, causing the spacecraft to “chase its tail” and expend a lot of fuel before ground controllers caught on and shut it down. Since then, the torque versus angle characteristics of deploying hinges have been carefully measured to ensure sufficient worst case torque margin (usually 100%).

The importance of mechanical testing and development was beginning to be fully realized. As payloads became more expensive and complex, the cost of neglecting ground development and test became much greater than the cost of realistic component and system level test programs.

1965: This was the year of a major reorganization, implementing the new concept of “projectization.” Previously, all integration and test work was by one organization divided into two activities, electrical and mechanical. Under projectization, each project or program had an individual management system, responsible for only one project and controlling the activities of both the electrical and mechanical people. The Mechanical Integration and Test Department assumed support responsibilities which included lending engineers and technicians to projects, conducting early development test work, Ground Support Equipment (GSE) design and fabrication, and model and mockup building.

1966: The Engineering Test Section of Mechanical Integration and Test Department had 20 people, three of them secretaries. LMDE testing was in full swing with the famous “trash can test.” The expansion nozzle of the LMDE was designed to crush on landing (if the LM should land on any projection) instead of tipping over the LM. To demonstrate that the hot nozzle would indeed crush under the LM weight, an apparatus was devised to simulate the landing conditions. A lot of money was saved by trying out the test apparatus with trash cans rather than with hot LMDE nozzles.

1967: On 27 February the Mechanical Test Department (as it was then called) had 60 people total. By September, the department had grown to 158 people, an all time high. One new project was the Hard Point Decoy Project (HAPDEC). The contract was awarded in October for a February ’68 launch. 1968: In July, the Mechanical Test and Support Equipment Department (as it was then called) had 96 people.

1969: In November, the department had 62 people.

1970: Work started on the Solar Array System (SAS) for Skylab, a 10 by 40 foot array that folded accordion style. The testing included vibration tests, deployment tests, and cold temperature tests. The “triple seven” (777) Defense Space Communication System (DSCS) program stated, eventually to launch 15 spacecraft, most of them successful.

1971: Fleet Satellite Communications (FLTSATCOM) for the Navy was started for a total of five to date, including structural test programs and an appendage development program. FLTSATCOM marked the first use of graphite in deployable booms and the first use of Linear Variable Differential Transformers (LVDTs) for test deflection measurements. Formerly, dial gauges were used to measure small deflections. Model 35 for the Air Force started this year.

1975: The High Energy Astronomical Observatory (HEAO) project started. Three spacecraft were produced, Flights A, B and C, each one different. The HEAO project took over the department test facility for its integration high bay. It was never given back. The department machine shop was acquired by Manufacturing in M3.

1977: John Otera became the Systems Test Support Laboratory (STSL) manager. The Tracking and Data Relay Satellite System (TDRSS) development test program stated, with very stringent stiffness test requirements. Autocollimators were used to measure angular deflections.

1978: Jim Rozelle became the Mechanical Integration and Test Department manager with 43 people total.

1980: Torque sensors were used for the first time for torque-angle testing on the Defense Support Program (DSP) spacecraft development model. A static load test on the TDRSS was conducted at the McDonnell-Douglas facility in Long Beach.

The TDRSS appendage development testing was completed and acceptance testing was started.

1981: LVDTs were first used with automated data acquisition equipment in stiffness testing for rapid multichannel acquisition and data reduction. Programs were written to give linear fits and hysteresis energy calculations for 6 by 6 flexibility matrices.

1982: A new mechanical test facility was added to M1. The department also purchased a quantity of 12” x 12” steel beams for use in large scale static load structural tests. Use of gas bearings for linear X Y displacement at temperatures below -250F was demonstrated in a simulated solar array deployment test.

1983: A major reorganization to accommodate growth. Jim Rozelle became manager of the Mechanical System Laboratory and Bob Jacobs stepped up to Mechanical Development Department manager.

The use of graphite reinforced plastics was becoming more common in space structures where strength, stiffness and light weight is desired. Instrumentation techniques to determine loads from small strains in this anisotropic material were developed.

The TDRSS spacecraft launch was highlighted by 100% successful appendage deployments. Special TDRSS separation band release tests were performed in support of the IUS “second stage” anomaly.

Richard dot J dot Wagner at gmail dot com

index.html, this hand crafted HTML file was created October 25.
Last updated October 25, 2010, by Rick Wagner.
Copyright © 2010 by Rick Wagner, all rights reserved.