BUMPER-CEV Version 1.71 is used to perform micrometeoroid/orbital debris (MMOD) risk assessments for the Orion Multi-Purpose Crew Vehicle (MPCV) spacecraft. BUMPER is the primary risk analysis program used by NASA to provide for reliable and safe operations of spacecraft exposed to MMOD impacts. When provided with the physical shape and orbital parameters of a spacecraft, and a clear definition of failure, BUMPER calculates the risk of failure from MMOD impacts for all surfaces on a vehicle. Thousands of hypervelocity impact tests have been performed on representative samples of dozens of spacecraft shields and subsystems, thermal protection system (TPS) materials, and other spacecraft components to determine MMOD impact parameters at the failure limits of the various subsystems. The resulting verified ballistic limit equations and damage formulas are coded in BUMPER. Different versions of BUMPER have been created for ISS (International Space Station), Shuttle, and other spacecraft that differ in the ballistic limit subroutines embedded in the code, as well as the user prompts and other code to control execution and output of the code.

The objective is to quantify the risk of MMOD impact damage and failure of the TPS materials and MMOD shielding protecting MPCV. MPCV MMOD protection requirements specify minimum acceptable protection levels of the spacecraft to reduce risk of crew loss, spacecraft loss, and damage that leads to early mission termination below a maximum allowable risk threshold. BUMPER risk assessments and protection system design trades are an integral part of meeting MPCV MMOD protection requirements. BUMPER assesses MMOD risk as a function of MM and OD environment models. Several dozen ballistic limit equations are included within BUMPER-CEV v 1.71. The ballistic limit equations are based on results of hypervelocity impact tests conducted by NASA on MPCV shielding and hardware, as well as results from numerical simulations of impact (hydrocodes).

This work was done by Eric Christiansen and Dana Lear of Johnson Space Center; James Hyde of Barios Technology; Thomas Prior of Hamilton Sunstrand; Eric Nielsen of MEI; Michael Bjorkman of Jacobs Technology; and William Bohl, Joshua Miller, Kevin Deighton, and Cory Foreman of Lockheed Martin. For further information, contact the JSC Technology Transfer Office at (281) 483-3809. MSC-25169-1