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Reply	Anonymous says: The wikipedia article on re-entry is very useful here.As far as I understand it, the blunt-end-first orientation is stable under those condition just as a shuttle-cock is stable nose-first, it seems counter-intuitive, but there are many other factors in stability apart from the orientation of least air resistance and pointyness  (no votes) Tags: technology, unanswered, transport, human body.
	posted on 2008-09-25 09:38:00 | Report abuse

Reply	John Gordon says: There may also be an element of heavy end first - if you throw a hammer up in the air then it always, as far as I can determine, falls heavy end first. Therefore if the re-entry vehicle was designed with all the heavy bits next to the heat shield then that end would naturally go first.  (no votes) Tags: technology, unanswered, transport, human body.
	posted on 2008-09-25 10:23:00 | Report abuse

Reply	whipster says: The center of gravity for the cockpit would be positioned such that it's orientation under these conditions would be blunt end first.You might expect that it would be undesirable to have high air resistance for re-entry.. but this is not so.The air resistance would be beneficial in aiding the object to achieve an acceptable terminal velocity, and allowing it to decelerate enough for a safe landing.just as John Gordon has mentioned, it's not so much the shape but the center of gravity of the object, that determines it's orientation under free fall conditions.I imagine that the shielding placed underneath the cockpit would have been designed very carefully to place the objects center of gravity in as lower position possible, to achieve maximum safety.  (no votes) Tags: technology, unanswered, transport, human body.
	posted on 2008-09-25 12:09:00 | Report abuse

Reply	Tom says: Basic principles or aerodynamics would show that the re-entry capsule design is going to show high stability with the 'fat end' first. The same as a rain drop (closer to a sphere than classically drawn - but the concept works), the shape of the blunt end entering the atmosphere first acts to stabilise the module as it travels by creating drag turbulence in a neat pattern around the pointy end - creating a good drag profile, actively braking the craft, and keeping it very stable. If the craft made re-entry in the other orientation, having the 'pointy end' first, the drag profile would be inherently unstable, as the vortices of turbulence would have very little to 'focus' them. The module would wobble and spin like a top. Creating a very bumpy ride for the astronauts, and because the friction would focus on the pointy bit, it would get very hot. With the blunt end first, the friction is spread over a larger area, allowing the heat to be dissipated more effectively, rather than building up concentrations of extreme heat.Centre of gravity (as John Gordon said) is an important design component to assist in making the orientation stable, and not have to rely on aerodynamics alone to force the re-entry profile you want.  (no votes) Tags: technology, unanswered, transport, human body.
	posted on 2008-09-26 03:01:00 | Report abuse

Reply	Anonymous says: The pointy end is attached by a thin but strong thread to a skyhook, so that whenever the craft wobbles threateningly it self-rights itself. Until the discovery of skyhooks (more technically known a LaCrochet points) by British construction workers in the late 1940s, space exploration was effectively impossible.  (no votes) Tags: technology, unanswered, transport, human body.
	posted on 2008-09-26 07:13:00 | Report abuse

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