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Old 04-15-2008, 01:36 PM   #1 (permalink)
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Question Aerodynamics of rockets vs. cars

Why do modern rockets have a blunt pencil shaped nose cone versus the streamlined 'boattailed' V2 designs of WW2 ?

I know that the boattailed approach is pointless because the smooth airflow passing over the rockets body meets up with the massive rocket behind it ... but I see a lot of pipes and other junk stuck to the sides of some rocket designs and have to wonder if it hurts the efficiency any.

I would think that up to a certain point, the same aerodynamic principles that apply to automobiles would also apply to rockets.
Once you go supersonic and then further, how do aerodynamics become affected by sleek shapes ?
If you recall, the tail on an X-15 is a wedge shape and does not taper back to a smooth teardrop profile.
Hypersonic designs and lifting body designs tend to look like a wedge as well, with what appears like no wings at all.

Further off topic, why do rockets shoot straight upwards versus flying to the edge of space and then turning on the rockets ?


The X-15 flew into very low earth orbit. What would keep the X-15 from continuing further into space ?
I understand that a certain speed must be achieved before you can break free of Earths' gravity, but why do we really need to start from ground level and fight our way upwards ?

It seems like an awfull lot of wasted fuel to me .

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