On Orbit Life Extension of the Minus Eighty Freezer MELFI Inside the Station Utilization

摘要

Because of the reduction on the remaining Shuttle launches, the initial mission that was assigned for MELFI, the Minus Eighty degrees Celsius Laboratory Freezer for ISS, has been significantly modified. While the design was made for a MELFI flying 15 times over a period of 10 years with individual missions no longer than 2 years, present scenario requires to have MELFI in orbit up to 7 years.Extending the MELFI on orbit life from two to seven years has required staggered assessments, each of them aiming at preserving as much as possible the existing design.The potential life limited items are evaluated. On orbit maintenance will be extended for a longer period and maintenance activities foreseen initially to be done on ground between flights will be adapted for orbit.Degraded modes are evaluated so that MELFI ensures its mission at the end of the life even with some off-nominal conditions.