I seriously doubt that it will be able to even take off with such a low air pressure.
Quote from: baldusiI seriously doubt that it will be able to even take off with such a low air pressure. That would be a great question for Mr. Hempsell if he ever comes back!I don't see how the altitude at Quito would be a showstopper. The current airport there is one of the busiest commercial airports in South America. So you have to build an extra long runway. What's the big deal with that? As for air frames cracking, just make sure the runway is made of high-quality, extra smooth pavement.
I don't see how the altitude at Quito would be a showstopper.
In commercial aviation, launching at higher altitudes seriously decreases the max takeoff weight and thus range/payload. I doubt this will be different from Skylon.
Because Ecuador is a backwaters, 3rd world country with no modern infrastructure that's too far away from the centers that matter? I respectfully disagree. YMMV.
But this is only assuming an ITAR free plane.
Launching out of South America means either high altitude and/or heavy jungle/rainforest. Finding 15 square kilometres either way might be hard or involve lots of hard work.
Quote from: Kharkov on 10/29/2012 12:42 amLaunching out of South America means either high altitude and/or heavy jungle/rainforest. Finding 15 square kilometres either way might be hard or involve lots of hard work.Err.. have you heard of Alcantara? Kourou is where?
A recent Mark Hempsell interview:http://www.talkingspaceonline.com/home/episode-434-skylon-with-sabre-single-stage-to-orbit.html
The new Quito airport is already going to be 4 km, as is. Honestly, I can't see the showstopper here. Fully loaded 747's fly at 40,000 feet every day. So it can't be the case that high-altitude per se limits the payload/fuel supply of air-breathing vehicles. Seems to me it would just be a function of take-off speed, which in turn would be a function of runway length.
Some ways to increase aircraft performance in hot and high conditions include:Reduce aircraft weight. ...Increase engine power. ...Increase the size of the wings. ...Add high-lift devices to the wings. ...Utilize assisted take off devices, such as rockets, to increase lift and acceleration.Inject distilled water during takeoff in the engine (compressor or combustor). Evaporating water reduces the temperature, so more fuel can be added, increasing power.Alternately, runway lengths may be increased to make up for reduced aircraft performance.
Warren, do some more reading an look at the components of the speed needed for orbital insertion. 99% of the energy is horizontal, not vertical. The reason that traditional rockets launch vertically is because they try to get away of the atmosphere as fast as possible due to their low isp. Skylon has 10X isp on the atmosphere, thus it's not a problem. You are trying to solve a not a problem.Infrastructure and business considerations are a lot more important. As I said, you can't beat Kourou in anything by five degrees from the equator. And you are assuming that there's no overflight problem at all! That any country will be ok with an hydrogen bomb flying above their cities? What about polar launches?
It's a robotic aircraft with a ridiculously high GTOW percentage of which is liquid H2.
In fact, since it uses O2 from the atmosphere when in plane mode, the amount of H2 is huge. Please remember that it's as or more heavy than an A380.
Think what would be the precautions if this was road transported, and what are the dangers in case of a crash, for example.
Think of the amount of JP8 and how does it burns vs. H2.