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Depends on how severe a dog-leg you fly.
Try it.
Depends on how severe a dog-leg you fly.
Try it.
Depends on how severe a dog-leg you fly.
From what launch site? To what orbit? With what vehicle? At what point in the flightpath?
Just try launching out of plane.
If you are so desperate to prove that it is impossible, show it yourself.
Worst case would be a 22.5° plane change, so let's use ~50% of that: 11°
DV: 1380 m/s
Extra fuel for plane change: 3618 kg
Max payload 2350 kg
Payload reduction: 154%
The calculations include negative mass for payload, so you would have to add larger fuel tanks to make it to ISS.
Then you need to include the increased gross mass to all the orbital maneuvers, so I'm guessing the final number would be closer to 200% payload reduction.
An aggressive rendezvous has nothing to do with launch location but rather the amount of dV expended in orbit. And it is a trade-off: do you want a shortened rendezvous time, if it results in even a 50% payload reduction?
Wait, you're talking about a plane-change on orbit, done by the propulsion onboard the spacecraft itself?
I'm talking about flying the launch vehicle sideways to change inclination as was performed on some Shuttle and Delta II flights.
Can you please make up your mind?
.... assumed that the spacecraft and its target were more or less in the same plane
My opinion is, there are too many unknowns in the system to make a definitive conclusion. Personally I like the idea of air launching an orbit bound payload. But the advantages and disadvantages have yet to be explored in real world conditions yet. I'll wait until they produce some hardware :thumbup:
- I can't be the only one thinking "go around, go around" on that landing video--way too high and fast, and they ate up a ton of runway in the roundout and flare...
That is the way we do things now using launch sites. But the target may be in the wrong position for a direct ascent by the time the launch site is in-plane.
NGC PR — REDONDO BEACH, Calif., Dec. 22, 2011 — Northrop Grumman Corporation expanded its commercial space portfolio with Stratolaunch Systems’ recent selection of Scaled Composites, a Northrop Grumman subsidiary, to build the largest aircraft ever constructed. This is the latest example of the company’s innovative solutions to challenging problems. Scaled Composites is developing an air-launch system for Stratolaunch Systems, which is a Paul G. Allen project that will revolutionize space transportation by providing orbital access to space at lower costs, greater safety and increased flexibility.
“This private spaceflight initiative represents a significant leap forward in defining technologies today which will open doors tomorrow for affordable commercial space transportation,” said Paul Meyer, vice president and general manager of advanced programs and technologies for Northrop Grumman Aerospace Systems. “Whether it be manned and unmanned aircraft, space systems or advanced technologies, we are focused on developing innovative solutions that enable the growth of the aerospace industry.”
{...}
I never suggested doing a direct ascent, rather doing a 'traditional' ascent with more 'dV expensive' manuvers to catch up to the target in a reduced period of time.
Then what are the dog-leg maneuver you're talking about?
The point is that a winged first stage makes it much easier to do a direct ascent.
Your continued statements that you're much smarter than most participants in the COTS programme, without any reasonable argument or example or calculation, simply doesn't impress me at all.
When exactly do you propose that dog-leg maneuver to occur?
And how much of an advantage will you gain by that method?
What does direct ascent have to do with space tourism?
Is this particular project even supposed to be manned?
I thought it was about flexibility.
How does "being a contractor" translate to: "not connected"?
So you don't say you're smarter, but you've spotted a flaw in a plan made by "Groups of smart, experienced people".