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Old 8th Jun 2013, 06:37
  #176 (permalink)  
Jonzarno
 
Join Date: Dec 2011
Location: Cambridge
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Vee-Tail-1

You obviously have insights into the cause of this accident that are not available to the rest of us and perhaps you would share them?

What we do know so far is that the pilot decided to pull the parachute because, for whatever reason, good or bad, he could not control the plane to a safe landing.

Given that he was in that situation, given the METARS at the time, possibly (again, we don't know for sure) in IMC and therefore unable to see where he was going: let's examine the consequences (not his intentions) of his two choices:

1. Pull the chute

He announces what he has done with a loud bang as the rocket fires and the parachute deploys.

He descends at 17 KTS, more or less vertically, clearly visible to everyone on the ground to the extent that people have time to pull out a smartphone, open the camera app and start filming once he is clear of clouds and takes over 30 seconds to reach the ground.

The mistake he apparently did make was to forget to turn off his engine.


2. He doesn't pull

He loses control of the plane and hits the ground at not less than 70 KTS, the clean stall speed of an SR22, obviously with the engine still running as well.

In doing that he has to dissipate at least seventeen times the amount of energy compared to the CAPS descent. As you know energy is a function of the square of speed so if he hit at, say, 100 KTS the amount of energy would be 34 times as much.

If he has completely lost control (and I repeat, we still don't know if or why) there's every chance it could be a spiral dive at a much higher speed with even less warning to those on the ground, even more energy to dissipate and no control whatever over what he hits.


As I say, we don't know what caused the problem. At this stage, all we can sensibly do is to analyse the consequences of the fact that the pilot recognised that he had a problem and followed his training in dealing with it.

A simple analysis of the physics involved as set out above shows that he did the right thing and that is borne out by what actually happened: nobody was killed, not only in this case, but also in every single other CAPS deployment within design limits that there has ever been.

Was he a hero (your word)?

No, I don't think so because that implies an act of courage carried out for the benefit of others.

Was he a good pilot?

In terms of his flying ability and aircraft control, we don't know because - I stress again - we don't know what caused the incident.

In terms of his decision to pull? You bet! It could have been so much worse both for him and for your friends on the ground.
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