Making Commercial Space Safe by Measuring Spacecraft Equipment Remaining Usable Life Before and After Launch

Abstract

An outcome of the ICBM, cold-war era was using probability reliability analysis to calculate equipment usable life/reliability using stochastic equations. Commercial and military procurement specifications for space vehicles still include the requirement for the space vehicle builder to calculate the probability of success (Ps) using the stochastic equations dictated in the contract. Using stochastic equations in a probability reliability analysis to quantify launch vehicle and spacecraft equipment reliability and confirming spacecraft equipment performance in a factory acceptance-testing program produces space systems whose usable life is dominated by premature failures that will cause a quick end to a commercial space tourism industry. The suppliers of electrical and mechanical parts promise that some will fail prematurely and yet no physical measurement of part or equipment usable life is contractually required before launch. Procurement contracts for space vehicles only require the builder to measure and confirm equipment performance and since there is no relationship between equipment performance and usable life, space vehicle equipment fails prematurely without financial penalty – a hold-over from the cold war. Using predictive algorithms in a prognostic and health management (PHM) program will measure space vehicle equipment usable life to identify the equipment that will fail prematurely for replacement. Commercial satellites that fail prematurely regularly are usually insured against premature failures, but the launching of tourists to space requires the game changing reliability centered, prognostic technology, which employs intelligent, self-prognostic equipment to stop surprise equipment failures that lead to catastrophic failures and loss of life. Using a PHM in the manufacture of space systems increase the safety obtained from using the NASA man-rating requirements. In a PHM, a prognostic analysis converts common equipment analog telemetry used during factory test to measure and confirm contractual equipment performance to a measurement of equipment usable life by demodulating telemetry behavior in time, amplitude, frequency and phase. Just as the police detective was replaced with the scientifically trained, forensic scientist; the medical doctor replaced by the scientifically trained radiologist to read medical images, the aerospace engineer needs to be replaced by the prognostician trained in completing a scientific analysis of equipment performance data to ensure space tourist safety. This paper includes the results from the prognostic analysis completed on commercial, military and NASA satellites, missiles and launch vehicles that identified the presence of accelerated aging in equipment analog telemetry test data from electrical and mechanical parts that were suffering from accelerated aging, missed by the engineering analysis completed by the equipment vendors, that failed prematurely. The results demonstrate that an engineering analysis and factory testing does not identify the equipment with parts suffering from accelerated aging that pass factory testing but will fail prematurely increasing of a catastrophic failure during the launching of tourist to space.