Fly to ISS in under two minutes

[ortemus74]

Flying at just 1.666 miles a second a scramjet spaceplane could fly to ISS in just under two minutes...<br />How would someone survive the G-force of that trip?<br />

 

[grooble]

They'll design new suits.<br /><br />

 

[mrmorris]

<font color="yellow">"After the astronaut(t) were smashed flat and their cardiovascular systems had collapsed from the 5-10 gee forces you are talking about..."</font><br /><br />5 Gs is fairly 'blah' for manned spacecraft.<br />10 Gs are rough, but can be sustained for brief periods of time.<br /><br />When Soyuz T-10-1 blew up on the pad -- the escape tower placed the cosmonauts under a 20G acceleration. Both survived and required only minor medical attention.<br /><br /><font color="yellow">"You must think these things thru if you want to be taken seriously. "</font><br /><br />Likewise yourself. The whole thread is as flawed at the base as the moon helicopter one for <b>several</b> reasons which make responses to the original question essentially meaningless.<br /><br />1. The original post gives only a velocity, rather than an acceleration (which is, by definition -- what Gs are).<br />2. The <2 minute statement assumes that the velocity is constant through the entire trip -- essentially stating that there *is* no acceleration or deceleration. Presumably, the <2 minutes is assuming that ISS is straight overhead (i.e. ~200 miles straight up), and the scramjet instantaneously has a velocity of 1.666 miles/sec, then reaches the ISS and instantly has a velocity of zero with respect to the station. This is the 'Jules Verne' method of space launches. The spaceplane would essentially act like a bullet shot from a gun, as in his story. I won't bother calculating the G forces required to get to the ISS. Jules' gun was later calculated to require about 47,000 G's. While the ISS wouldn't need quite that much -- astronauts unlucky enough to be in this spaceplane would still be a big red spot on the aft bulkhead at launch, and a matching (somewhat smaller) red spot on the forward bulkhead upon reaching what used to be a space station before it was destroyed by the world's biggest bullet.<br />3. #2 is further garbage because it ignores orbital mech

 

[CalliArcale]

<blockquote><font class="small">In reply to:</font><hr /><p>Well as soon as you were in orbit I don't believe there would be any G forces. While still in Earths atmosphere a pair of brown trousers might be handy. <p><hr /></p></p></blockquote><br /><br />Actually, the presence of the atmosphere does not create G forces.<br /><br />G force is basically the perception of acceleration. It's not a true force -- it's the net force you feel due to acceleration. So you will experience Gs, whether you are in or out of the atmosphere, anytime your spacecraft is firing its engines.<br /><br />Astronauts have remarked how, after a while in space, even the modest acceleration produced by the Shuttle's OMS engines produce noticable Gs. <div class="Discussion_UserSignature"> <p> </p><p><font color="#666699"><em>"People assume that time is a strict progression of cause to effect, but actually from a non-linear, non-subjective viewpoint it's more like a big ball of wibbly wobbly . . . timey wimey . . . stuff."</em>  -- The Tenth Doctor, "Blink"</font></p> </div>

 

[nexium]

Lets try some simple aritmetic: s = 1/2 at squared = 112,000 meters, if a = 70 = 7.2 times Earth's surface gravity and t = 40 seconds until the scram jet has too little air to funtion. v= at = 2800 meters per second which is about 1.666 miles per second, so about 2 minutes is correct, at an average of 7.2 g which the astronaughts could tolerate for 40 seconds with reasonable safety. The craft would then coast = decelerate at about 0.9 g upward for about 80 seconds to a lower speed, before being rammed from the rear by the ISS which is orbiting almost 5 miles per second. A near miss is likely as the scram jet cannot fine tune the sub-orbital trajectory the last 80 seconds. Neil