First NTSB reports from Virgin Galactic SS2 crash

Branson in SS2SS2-crash-site

An article on the first NTSB reports from investigation into the SS2 crash last fall appeared on The Daily Beast, here.  There is a similar article on ABC news here.  Below I analyze this in terms of the Crash Rate Equation.

NUMERATOR TERMS – The first and main point of the article is hidden political pressure on the FAA to grant waivers and special treatment that VG didn’t even ask for.  This is doing VG no favor, as we well saw demonstrated by the crash.  But it illustrates the extremely high value to someone of this project, i.e. very high V(f) in the numerator, increasing the crash rate.

DENOMINATOR TERMS – The other points of the article mention lack of practice and lack of fidelity in the testing.  In terms of the equation, and the Cd/D term (development costs divided by defect ratio), they were scrimping on the Cd component from testing costs, resulting in a high defect ratio D.  This term is deadly if mishandled because it is a leverage term, with D going up as Cd goes down and then the quotient of them amplifying the effect.  It’s great if you are spending enough to get D down, but horrible if you aren’t.

You CANNOT fix this term by examining specific causes and fixing only those.  If you don’t take away the general lesson to beef up Cd and get D down, then there will just be other problems that cause other crashes.  I sent Richard Branson a copy of my book, but he didn’t acknowledge it and so probably ignored it, if his staff even forwarded it to him.  Most people like this (I obviously don’t know Richard personally) think just because they succeeded at some kind of business, they “know everything already.”  They may even be able to pick good people to work for them.  But the guy in charge has to understand where not to apply too much pressure on Cd, because no one can overrule him on that.


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