One can determine rotational speed at a non equatorial latitude by taking the rotational speed at the equator and multiplying it by the cosine of the degree of latitude. Sea Launch gets the full boost from the equatorial latitude of 464m/s. KSC's has a latitude of 28.5o and thus gets a boost of 408m/s. The difference is only 56m/s. The reason why Sea Launch went to the trouble of launching at sea was because it was launching communications satellites destined for geostationary orbit. To get to that orbit a plane change maneuver needs to be done to reduce the orbital inclination to 0o. While the velocity boost gained over KSC was small the plane change maneuver was eliminated. The same rocket could deliver 17.5%-25% more payload because it didn't need to do that plane change maneuver.
It's really a question of how much would it cost to build versus Dramatically lowering the costs of orbital launch.If the rocket business goes into a fierce price war you might see movement toward this idea as competitors looks for any edge.
Does this help reduce the cost of access to space by an order of magnitude?
Compared with that, the CSG (Centre Spatial Guyanais) sits at 5° north, and has a boost of 460m/s. It's just 4 m/s short of being perfect, without the hassle of launching stuff off from an oil rig. That's why the russians were interested in getting a soyuz-launchsite over there.
Considering the logistical nightmare it would take to build this thing (I'm assuming you've never been to Ecuador )
In fact, the ramp has no advantages.
I never suggested this be done in a high mountain.THAT, would be expensive and not worth it IMO because of the logistics ofbuilding the Ramp, and bringing the vehicle components to the site.I suggested a lower valley, at most 1km high so that costs tobuild and operate are low.The savings from this approach are as I stated before.DUMB, solid boosters, Lots of them. No guidance required.An initial Downward slope to give the rocket inertia.Equatorial Launch bonus, both to orbit and orbiting the plane of the solar system.Atmosphere thins faster at the equator due to equatorial bulge.Used Boosters can braked before leaving ramp so that they don't land on a adjoining landscape/country.Unfortunately I think about 3,000 MPH is the maximum feasible launch speed due to still thick atmosphere.And I don't think it's worth it to building a ramp 5-6 KM high, in some god forsaken peak, just to getto maybe 5,000MPH.
Emphasis mine. I see where the misunderstanding is now - you're assuming the ramp would save fuel if you can get your vehicle to 3000MPH (because the shuttle had spent 60% of its fuel to get to 3000MPH) - but the problem is that unless you are at the same altitude as the shuttle was when it was doing 3000MPH (~30 Miles or so) then the air friction of the lower atmosphere will wipe out most of that saving.
Near the Equator the atmosphere thins out faster due to Earth bulging distortion.
For Missions in the solar system orbital Plane, No need to use extra fuel to maneuver you ship to this attitude.
But they were not ramp launched. A ramp with a 3 : 1 slope is what I am proposing.
Equatorial orbital insertion are the majority of non-military launches.
Not even Sea Launch thought so, or they would have propositioned some Equatorial nation to build a scaled down version of the 10 mi ramp. Even an additional 2,000MPH is nothing to sneeze at.
Jim, Regarding equatorial insertion, which is required for geostationary satellites. go look at this site http://www.orbiter-forum.com/showthread.php?t=26464Remove all the PLA, Russian, and US Military. Do you see a majority of launches beingweather and deep space launches? I don't.
But still Liquid rockets are more complex and less reliable.
Several proposals for impulsive methods exist: linear electromagnetic motors, light gas guns, air-breathing first stages, ram accelerators. All of the above seem fairly feasible, so long as a customer could be found who will pay for thousands of tons of high-G cargo launched per year.
Maybe a better question is, are solid rockets overpriced? maybe because the only alternativeis Liquid fuel rockets and there is not a 3rd option.
A launch assist could be a game changer is if it enables a reusable quasi-SSTO, eg. expendable dumb tank, rest of the veichle reusable with minimal refurbishment and low turnaround time, say just thermal shield replacement and add a new refuelled tank. This has to use liquid engines, of course.Any reasonable assist, including high quote ramps and air launch, will probably not be enough to achieve this or simply there's not the request for the high number of launches required to justify the huge r&d, investments and fixed costs.
Quote from: Admiral_Ritt on 01/05/2016 10:29 pm But still Liquid rockets are more complex and less reliable. Not true for new solid motors