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I agree that the actual delta-v produced by any practical rocket that reaches escape velocity must be higher than 11.2 km/sec. This is because (a) the acceleration profile is not a step function, and (b) using the highest acceleration that the astronauts were capable of enduring would result in the spacecraft overheating because of air resistance (those pesky Engineering considerations...  ).
This, however, that does not change the fact that the escape velocity at the Earth's surface is approximately 11.2 km/sec. This gives the absolute lower bound on the delta-v that must be given to an object that is to escape the Earth's gravity.
If you have an important point to make, don't try to be subtle or clever. Use a pile driver. Hit the point once. Then come back and hit it again. Then hit it a third time - a tremendous whack.
--Winston Churchill
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And plenty of cogent reasons why it would be better to build and launch ships from orbit or a body with a lower escape velocity requirement (putting to one side the practicalities of setting that all up in the first place - nice to dream).
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Just do it when there is no wind. Can't believe NASA hasn't thought of this.
Oh wait....maybe it's air resistance that's the problem, not wind resistance... 
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No, that's a X-15 covered with ablative heat protection, most probably before the flight.
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air+velocity=wind
HOw fast is a rocket going?
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Munchies_Matt wrote: air+velocity=wind
It's wind if it's the *air* that has velocity, not an object moving through it.
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I see, this is your deffinition of wind is it?
What do you call a windscreen then? 
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If you get your scientific knowledge from badly-named items then it's just as well you don't work at NASA.
What kind of food stuff is a peanut? A strawberry? What's your pencil lead made from? What's tin foil made from? What kind of animal is a koala bear? What kind of animal is a horned toad? Where was Chinese checkers invented?
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Now you're getting your scientific info from Merriam Webster? Not much better.
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Whereas you get yours from your 'opinion bank'.
Unlike many people (everyone?) here I studied physics in depth, since my principal formation was in mech/aero engineering.
The mistake you make is assuming the earth has some relevance in this. When the object experiencing the wind is not moving relative to the earth you call it 'wind'. When it is you call it 'air'.
Earth centric views in science died with the church, you do remember the heresy of Galileo dont you?
The correct way to view this is the body and air have different velocities. This creates wind. Period.
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Munchies_Matt wrote: I studied physics in depth, since my principal formation was in mech/aero engineering.
I find that hard to believe when you cite a dictionary as proof.
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I find your inability to accept that a dictionary and physics have the same deffinition hard to believe.
How about engineering? Here are some pics of wind resistance:wind resistance - Google Search[^]
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Most of those pictures do relate to actual wind though.
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Calm down. Don't you know that the only difference between a "science" reporter and an ordinary reporter is that the "science" reporter can count to 21 without getting arrested for indecent exposure? 
If you have an important point to make, don't try to be subtle or clever. Use a pile driver. Hit the point once. Then come back and hit it again. Then hit it a third time - a tremendous whack.
--Winston Churchill
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Then it's easy... just wait for non windy days... 
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air doesnt have any resistance until it has velocity relative to the object whereupon it is wind. 
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Tell that to some underpants out in the wild...
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The theory explained in the book "Limit" is way cooler.
M.D.V. 
If something has a solution... Why do we have to worry about?. If it has no solution... For what reason do we have to worry about?
Help me to understand what I'm saying, and I'll explain it better to you
Rating helpful answers is nice, but saying thanks can be even nicer.
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The narrator got it a bit wrong about why it's easier to go faster in space.
Sure, gravity, as he claims, would be an obstacle IF one were opposing it, but the real hero (or lack thereof) is that there's no atmosphere to (1) slow the vehicle down, and (2) heat the vehicle up.
It would go even slower under water . . .
| Ravings en masse^ |
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| "The difference between genius and stupidity is that genius has its limits." - Albert Einstein | | "If you are searching for perfection in others, then you seek disappointment. If you are seek perfection in yourself, then you will find failure." - Balboos HaGadol Mar 2010 |
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Just goes to show how far ahead of its time the SR-71 was.
"the debugger doesn't tell me anything because this code compiles just fine" - random QA comment
"Facebook is where you tell lies to your friends. Twitter is where you tell the truth to strangers." - chriselst
"I don't drink any more... then again, I don't drink any less." - Mike Mullikins uncle
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This morning I wanted to leave to work with my motorcycle. Everything seemes fine, but after a few meters of driving the engine just stalled. Retried, same thing, retried, same thing, ... 
A (knowledgeable) friend of mine gave a few options:
* fuel out (very unlikely since I only drove 200 km or so. It should be able to do 240-300 km with one tank.
* dirt in the ABS sensor or something ?
* Perhaps a mouse or marter (weasel like creature) bit some cables or something (to be checked still)
Question is: does anyone think of something else I could check?
to be complete:
* Honda XL700VA (transalp) 2008 (with ABS)
* I drove this Wednesday and everything was fine.
* The engine starts fine, it's only after driving a few meters that it stalls (this morning I did less than 100 meters and it stalled 4 or 5 times)
* Don't think I saw any weird lights on my dashboard
* It had a checkup a few weeks backs and have since driven about 300 km without issues.
Checkup was, engine oil and filter, new sparkplugs, valve play (? that which you measure deep down in the engine and can only by like a few tenths of a millimeter) and air filter.
thanks.
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S**t in the carburetter?
Or water in the fuel, or the fuel is very old (it doesn't age well) and the engine doesn't like it.
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