Author Topic: Dnepr launch - July 26: Failure  (Read 39405 times)

Offline edkyle99

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Re: Dnepr launch - July 26: Failure
« Reply #80 on: 09/27/2006 08:11 pm »
SpacemanSpiff - 27/9/2006  1:06 PM

Failure Investigation Report has been issued:

See the 'News' section.

Looks like Dnepr launches are on hold while they check for the problem they cite in the article. Does anyone know what they are talking about? Sounds like either a wiring problem (short circuit) or an avionics control problem...


It sounds to me like a mechanical, not an electrical, problem.  The hydraulic drive used to control the position of combustion chamber #4 (of four) malfunctioned due to overheated heptil fuel being fed into the hydraulic drive.  (The heptil fuel may have been the hydraulic "working medium", but I'm not sure about that.)  The heptil fuel overheated due to the failure of insulation on the fuel line leading to the pump.  Why did the insulation fail?  "non-compliance with the design and manufacturing documentation" - a manufacturing defect!  

This was an older missile, so it seems likely that the insulation either degraded due to age or had suffered damage during the transport/handling process.  But that's just a guess.

 - Ed Kyle