Historical Background. The original motivation for thisHandbook came from personnel of The Aerospace Corporation (TAC),who are technical advisors to the Air Force Space and MissileSystems Center. Over the preceding two decades, TAC had observed aseemingly endless series of errors and anomalies in the acquisitionand analysis of structural dynamic and aeroacoustic data. Toevaluate the scope of data analysis errors alone, TAC arranged a"round robin", where identical magnetic tapes dubs of shorttime-limited stationary random signals were sent to several dataprocessing centers for a 1/3 octave band analysis with theirnormally-used equipment. Ten centers responded with analyzed datathat revealed discrepancies of nearly 20 dB at some frequencies[1.1, 1.2]. Rather than continue to accept this situation, Don Wongof TAC arranged to have the Air Force fund the development of aHandbook that would help reduce the variability and eliminate theerrors commonly found in measured dynamic data. The Jet PropulsionLaboratory (JPL) was selected to prepare the Handbook, as well asperform any research required to achieve the Handbook objectives.Harry Himelblau of JPL was appointed the Task Manager for thepreparation of the Handbook. He was assisted by Allan Piersol ofthe Piersol Engineering Co., James Wise of JPL, and Max Grundvig,who was brought out of retirement from TAC for this assignment.Additional assistance was provided by the numerous reviewersacknowledged in the Foreword.
Purpose. The purpose of this Handbook is to provideguidelines for acquiring and analyzing structural (or mechanical)shock and vibration, and acoustic and aerodynamic noise data fromflight and ground tests for all categories of aerospace vehicles.The guidelines may also be used for dynamic measurements on avariety of ground and sea transportation vehicles, industrialmachinery, and civil engineering structures (e.g., the response ofbuildings to earthquake loads). The objectives of the guidelinesare to ensure the accuracy and reduce the errors and variabilityoften associated with the acquisition and analysis of dynamic data.Specific procedures are provided unless they are highly dependenton the particular applications or instruments utilized. Theultimate goal is to make accurate measurements of the dynamicphenomenon of interest, without that or any other phenomenoninfluencing the measurement process.