<prompt> Translate the following text to EnglishKifaa muhimu cha kuegemea kwa F-22 ni wakati wa wastani kati ya matengenezo, iliyofafanuliwa kama idadi ya masaa ya uendeshaji kwa ndege kugawanywa na idadi ya vitendo vya matengenezo.  <response>: A key reliability requirement for the F-22 is mean time between maintenance, defined as the number of operating hours for the aircraft divided by the number of maintenance actions. 