The Saturn V dynamic test vehicle, designated SA-500D, is a prototype Saturn V rocket used by NASA to test the performance of the rocket when vibrated to simulate the shaking which subsequent rockets would experience during launch. It was the first full-scale Saturn V completed by the Marshall Space Flight Center (MSFC). Though SA-500D never flew, it was instrumental in the development of the Saturn V rocket which propelled the first men to the Moon as part of the Apollo program. Built under the direction of Dr. Wernher von Braun, it served as the test vehicle for all of the Saturn support facilities at MSFC.
SA-500D is the only Saturn V on display that was used for its intended purpose, and the only one to have been assembled prior to museum display. It is on permanent display at the U.S. Space & Rocket Center, Huntsville, Alabama.
Pre-flight configurations
Before a Saturn V could be launched, engineers needed to verify that their design had accounted for everything the rocket would encounter on its journey, from assembly to the launchpad and from Earth to the Moon. To validate the Saturn V design and procedures, they created five pre-flight configurations for testing. These configurations were subjected to tests simulating all aspects of flight preparations and flight itself, and all the tests needed to demonstrate satisfactory results before MSFC would certify the Saturn V to fly.
SA-500D was one of the five pre-flight configurations of the Saturn V. This configuration showed the Saturn V's "bending and vibration characteristics" and verified "the adequacy of guidance and control systems' design." The rocket's of thrust would generate vigorous shaking and it was important to see that the rocket would not shake apart or vibrate itself off-course.
Other pre-flight configurations were: Battleship test model, used for initial engine firing and design improvements Structural test model, to certify the structure for loads during launch at the anticipated temperatures, and to assess the stiffness of each stage SA-500F, the facilities checkout model, verify launch facilities, train launch crews, and develop test and checkout procedures. SA-500T, all systems test model, for static firing of engines in the flight configuration
The vehicle designated SA-500D did not include an Apollo spacecraft, but boilerplate parts were used during testing to verify the entire system.
Development of the test article
The Saturn V consisted of three stages and an Instrument Unit (IU). The first stage, S-IC, delivered thrust and delivered the other stages to . Afterwards, it was jettisoned to fall into the Atlantic Ocean and the second stage continued acceleration. The second stage, S-II, was responsible for lifting the remaining parts nearly to Earth orbit. The third stage, S-IVB provided the final push to orbit and the trans-lunar injection burn to set the Apollo spacecraft on a course to the Moon. The IU was the guidance and control computer. SA-500D was the assembly of these components for dynamic testing.
The Saturn V dynamic test stand with "electrodynamic shakers" provided a table capable not only of holding the Saturn V fully assembled and fueled, but also able to simulate the vibrations that would be generated by rocket engines.
The components used for testing were developed from 1964 to 1966, and the tests conducted in 1966–67. Because the Saturn V shared some components with the Saturn IB, some of the components for SA-500D were initially used for dynamic testing with the Saturn IB stack.
In naming the individual stages, MSFC used the stage designation with a suffix indicating its purpose. For example, S-IC-D was the first stage, S-IC, for dynamic testing, and S-IC-1 was the first flight model of the first stage. Suffixes used were S, for structural, F for facilities, T for all-systems test, and D for dynamic testing.
Following is a history of each component of the dynamic test article in order of appearance.
Apollo boilerplate
Development of the test article started from the top. A boilerplate Apollo spacecraft, BP-27 together with LTA-2, was used for all configurations of dynamic testing. The boilerplate took the place of actual flight hardware. Boilerplate size, shape, mass and center of gravity were the same, but it was not necessary for the entire Apollo spacecraft to be complete to commence dynamic testing. The boilerplate was outfitted with instrumentation to record data for engineering study and evaluation.