Aerospace Instrument-Making Annotation << Back MODEL FACTORS ANALYSES FOR ESTIMATING TRAVELLING WAVE TUBES OPERATIONAL FAILURE RATE P.S. Korolev, S.N. Polesskiy, Yu.О. Serebryakova, А.Е. Tseplina Traveling wave tubes (TWT) are widely used in power amplifiers for radio means of information transmission, including in space equipment. This is due to the fact that for them there are high requirements to ensure dependability, for example, due to the lack of possibility of maintenance for a long period of active existence. Hence the problem of warranty and reliable evaluation of individual dependability measure, in particular, reliability, because of uncertainty in choosing a mathematical model from the available set because of its variety. They include many factors that take into account the TWT parameters, including specific operating conditions (temperature, electrical parameters, vibration, etc.). The purpose of the work is to conduct an analytical review of mathematical models to improve the numerical evaluation reliability of the TWT operational failure rate due to the criterion of evaluation detail choice. The objects of study are travelling wave tubes. Mathematical models of TWT operational failure rate presented in actual scientific and technical and specialized sources became the subject of research. There is a detailed study of mathematical models for assessing the TWT operational failure rate in this paper. The analysis of parameters which are used at an operational failure rate estimation in each considered mathematical model is carried out. The most common causes of TWT failures are identified and generalized. The key factors that have the greatest impact on the TWT dependability are temperature and production technology. As a result, recommendations for the use of four mathematical models that will help to achieve the most reliable numerical estimate of the TWT operational failure rate are given. However, it is shown that in common they do not take into account all the key factors. Keywords: Dependability, operational failure rate, reliability, traveling wave tube, temperature, production technology. DOI: 10.25791/aviakosmos.06.2020.1164 Pp. 40-49.