Wednesday, 1 August 2012

A Strange Incident

 Thanks to those who are working on removing the offending reference to 'QC.'    

 More on the Raytheon/Beechcraft King Air 200 incident at the Olympics.  The aircraft was operated by ASL of Liege, Belgium.   It is still unclear what she was doing - although she seems to have been fitted with a UHF aerial, so she MIGHT have been re-transmitting TV signals, although it seems a very odd way of doing it (why not just use a satellite van, like everybody else?).  The other published explanation - cameraplane - makes even less sense.   The aircraft does not appear to have been fitted with camera ports, and is pressurised, so any cameraman would have to record through windows.  There are good reasons why tv stations usually use unpressurised helos for this work.
The claimed 'total electrical failure' seems unlikely.    As an aircraft engineer has pointed out to me this was probably intended to be a reference to a failure of the AC supply.  The King Air also has a 28-volt DC supply, using a NiCad battery on most models (you can get differences of course between different types of King Air).

Most of the instruments in the King Air are fed off the AC supply, so the reference to flying to Cambridge Airport using a compass and maps would make sense, if she were on battery power.  There are however TWO independent sources of AC supply in the King Air, so we are talking a rare double failure, subject to the next point, about the inverter switch.  

The only comparable incident any one could tell me about was the tragic crash of Super King Air 200 N81PF at Strasburg Colorado on 27th January 2001, killing 8 members of the Oklahoma State University basketball team.   Having suffered a double AC supply failure the aircraft plunged out of control some 20,000 feet into terrain, with the nose 80 degrees down at one point.  That is quite a steep dive!   

This incident was already on my radar, as the German DVD had sabotaged a number of aircraft carrying British or American sports teams over the years, an issue I deal with in Spyhunter. The NTSB could not find the cause of the electrical failure, nor does their typically thin report (with respect) explain how losing the AC-instruments could cause an experienced pilot in command to lose situational awareness so completely, when he still had his pressure instruments.

Another gaping hole in the report is the failure to explain how the three items of equipment which could have led to a double ac supply failure, including the inverter switch, went walkies from the wreckage.   Tampering with the inverter switch is one possible explanation for a double AC failure.

The inverter by the way converts DC power from the engine-driven generators to AC.   The NTSB  speculated that the PIC might have forgotten to switch inverters, but frankly the idea that an experienced pilot did not know what all those knobs and switches were for is fanciful.  Just about the first thing you do before flying a type for the first time is to study the instrument panel.   Aircraft do come with instruction booklets!

I would like to know more about this incident.   

By the way the only reason I do not acknowledge experts who have given me technical assistance is because they do want to be acknowledged publicly.  I don't blame them!  Being out in public means taking flak.  That's what I'm here for.   

Nice to see Romney's gaffe-prone overseas tour over.  It's cost enough votes already.  He seems not to have noticed that the Cold War ended in 1991.   Possibly he has not heard of China, the only explanation I can think of for his remarkable assertion that Russia is America's most dangerous geopolitical rival.       

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