Thursday, September 13, 2012

This is another NASA management blunder!

Remember one of reasons the space shuttle was decommissioned was to improve crew safety and that is not the case with crew modules! Ironically only a privatized space shuttle can have crew escape pods that would protect the crew during every phase of flight. This is another NASA management blunder. Recently published statements attributed to NASA state that the Orion Multi-Purpose Crew Vehicle Is: “designed to be 10 times safer during ascent and entry than its predecessor, the Space Shuttle.” As a retired NASA engineer with extensive experience in the operation of crew modules, I challenged the NASA Office of Safety and Mission Assurance about the authenticity of this statement.  Their reply (see below) was the Orion failed to meet the safety requirements for entry during their Constellation Program evaluations and that they have failed to establish a Level 1 set of requirement for the commercial crew modules and Orion MPCV. It is my opinion that the Commercial crew modules and Orion MPCV are potential deathtraps and NASA has misled Congress about the safety of these vehicles. While the crew escape tower on the MPCV may provide significant improvement over a Space Shuttle without crew escape pods, it does not negate the many factors that have made crew modules a death trap during the re-entry phase of flight. As example, historically the Russian Soyuz crew module’s safety record is not significantly better than that the Space Shuttle. While the Soyuz crew module has experienced a failure of the escape tower, it has been the re-entry phase of flight that has proven to be the fatal environment for flight crews. Potential fatal crew module failures are:   ·        Every crew module flight is a test flight! Manufacturing errors have occurred.   ·        Crew modules have very limited cross range capability which could require a reentry into unacceptable weather conditions. ·        Crew module’s notorious reentry errors result in an expanses landing zone that could prevent rapid access to the crew in dire circumstances. ·        Parachutes are known to fail. This is another unacceptable single point failure. There are too many potential failures with fatal consequences for a crew module to be considered for 21st century human space transportation. The Russian Soyuz crew module is still in service only because their government cannot afford to develop a safer reusable lifting body winged runway landing crewed spacecraft. Email reply: Excerpts from NASA Office of Safety and Mission Assurance: “At PDR, the Cx (Orion) design PRA estimate was better than the requirement for ascent and not there yet for entry. We don’t have a set of level 1 requirements yet for the next NASA developed human system, but we do plan to use the Cx numbers above as part of our human rating requirements set for commercial crew to ISS.  I agree this will be a challenge for any capsule for all the reasons you give if not more.”

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