Space tourism. Not to orbit but to a better view.

[spacefire]

LEO <div class="Discussion_UserSignature"> <p>http://asteroid-invasion.blogspot.com</p><p>http://www.solvengineer.com/asteroid-invasion.html </p><p> </p> </div>

 

[spacefire]

about 1000km <div class="Discussion_UserSignature"> <p>http://asteroid-invasion.blogspot.com</p><p>http://www.solvengineer.com/asteroid-invasion.html </p><p> </p> </div>

 

[no_way]

<blockquote><font class="small">In reply to:</font><hr /><p>1:00 = Travel time from Manhatten to JFK 0:45 = Check-in time 0:30 = Boarding time 0:15 = Taxi time Total pre-departure time = 2:30. (and another 2:30 on the other end) <p><hr /></p></p></blockquote> People make that argument a lot against suborbital point-to-point travel, i.e. that the saving in flight time will be neglible when compared to total trip time that involves all these preparations. This as compared to current air travel. I beg to differ. First, if one company would establish such a service right now, we would have obviously a very different market from current air travel which is almost a century old. It very likely would not fly out of a large commercial airport, and you very likely wont have thousands of people filling up your spaceport terminals. In fact, you very likely wont be boarding because you are a wealthy businessman and wanna get to other coast fast, but because you'd like to go on a best roller coaster ride available and dont mind ending up thousands of miles away from where you started. It took aviation how many years before getting to the point of regularly scheduled long-distance flights, with cabin service ? Before that, most of the customers on paying flights were in dire need or just daredevils and yahoos. In short, this market would not be in direct competition with air travel for quite some time, if ever, and its merits should not be pitted against it.

 

[JonClarke]

M 3.2 was an emergency limit, 2.8 is more like the operational limit. Still very impressive though. But it was a very impressive andmuch underrated aircraft, at least in the west. <br /><br />Jon <div class="Discussion_UserSignature"> <p><em>Whether we become a multi-planet species with unlimited horizons, or are forever confined to Earth will be decided in the twenty-first century amid the vast plains, rugged canyons and lofty mountains of Mars</em>  Arthur Clarke</p> </div>

 

[JonClarke]

Very nice images spacefire! How did you do them?<br /><br />Jon <div class="Discussion_UserSignature"> <p><em>Whether we become a multi-planet species with unlimited horizons, or are forever confined to Earth will be decided in the twenty-first century amid the vast plains, rugged canyons and lofty mountains of Mars</em>  Arthur Clarke</p> </div>

 

[drwayne]

I don't think the 25 was under-rated in the west. In fact, it was somewhat over-rated, as there were a lot of assumptions made about its abilities as a dog-fighter than turned out to be wrong, and led to the F-15 being what it is.<br /><br />It is a superb interceptor to be sure.<br /><br />Wayne <div class="Discussion_UserSignature"> <p>"1) Give no quarter; 2) Take no prisoners; 3) Sink everything."  Admiral Jackie Fisher</p> </div>

 

[spacefire]

Google Earth. Free download! Some urban areas have such high res you can spot people. <div class="Discussion_UserSignature"> <p>http://asteroid-invasion.blogspot.com</p><p>http://www.solvengineer.com/asteroid-invasion.html </p><p> </p> </div>

 

[j05h]

>How about suborbital trips to about 1000km altitude as an intermediate step between hops to the edge of space and full-fledged orbital trips? <br /><br />That sounds like the outside of potential range for SpaceShipTwo (or Three?) - Burt has talked repeatedly of longer spans of freefall and higher altitudes. It definitely has potential as a competence-building range.<br /><br />Josh<br /><br /> <div class="Discussion_UserSignature"> <div align="center"><em>We need a first generation of pioneers.</em><br /></div> </div>

 

[tap_sa]

<font color="yellow">"I wonder if a design like the SS1, but beefed up, would work for such re-entry speeds."</font><br /><br />The problem remains the same. If you drop straight down from 1000km altitude you hit the upper atmosphere at about 4000m/s. Four times faster than SS1 max speed. Yet you have the same distance during which you have to get rid of that speed. Trying to somehow make it softer by circling down doesn't help because it's the vertical velocity component you are dealing with. You have to get rid of it, and fast, or you'll plunge into lower atmosphere way too fast and burn up.<br /><br />If your reentry angle is shallow then you can make thing softer with wings, cg trimmed capsules, or ...*tadaa!*... lifting bodies. You want to use the lifting force to linger longer in the upper atmosphere while bleeding of your speed.<br /><br />Check the specs of suborbital Mercury flights for comparison. Their max speed was about 2300m/s, apogee was below 200km and still peak reentry G was over 11 due to completely ballistic reentry (the capsule didn't generate lift).<br /><br />If you want to safely jump to 1000km altitude the trajectory has to be relatively wide arc, meaning you need more deltav than straight up'n'down road. How wide arc and how much deltav, dunno, that's a complex computation involving L/Ds, drag coefficients, atmospheric properties at different altitudes and whatnot. IIRC ICBM's apogee is close to 1000km, but the reentry of RV is anything but gentle.

 

[spacefire]

yes but won't a shuttlecock configuration be able to gain some forward momentum (not much, it's a high drag configuration) and circle in the upper atmosphere? <div class="Discussion_UserSignature"> <p>http://asteroid-invasion.blogspot.com</p><p>http://www.solvengineer.com/asteroid-invasion.html </p><p> </p> </div>

 

[tap_sa]

LINK<br /><br /><i>"Another biological flight was launched on May 28, 1959. Aboard Jupiter IRBM AM-18, were a 7 pound (3.2 kg) American born rhesus monkey, "Able" and an 11 ounce (310 g) South American squirrel monkey, "Baker". The monkeys rode in the nose cone of the missile to an altitude of 360 miles (579 km) and a distance of 1,700 miles (2,700 km) down the Atlantic Missile Range from Cape Canaveral, Florida. They withstood <b>accelerations 38 times the normal pull of gravity</b> and were weightless for about 9 minutes. A top speed of 10,000 mph (4.5 km/s) was reached during their 16 minute flight."</i><br /><br />Tough monkeys indeed. Virgin Galactic customers might complain about the 38 Gs though...

 

[spacefire]

I think the 'Prime' LB went to altitudes of 1000km, but astronautix.com doesn't give the re-entry G loading. <div class="Discussion_UserSignature"> <p>http://asteroid-invasion.blogspot.com</p><p>http://www.solvengineer.com/asteroid-invasion.html </p><p> </p> </div>

 

[tap_sa]

1500km apogee (says astronautix) and travelled nearly 7000km downrange. Notice that the LV was Atlas, it could have put the thing into orbit but they were testing returning from LEO and doing high crossrange maneuvers.