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DARPA selects Boeing to work on XS-1


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It's a winged rocket that flies a powered ballistic trajectory and subsequently lands via aerodynamics, it's not a winged air breather than flies an aerodynamic trajectory.  Therefore it 'solves' most of the problems of air launches by not being an air launch in the first place.  (Or, to put it another way - the problems of air launch comes from being limited to wingborne air breathing altitudes and speeds.)  It also gives away the two advantages that air launch does have...  First by requiring a dedicated vertical launch facility.  Second by carrying a portion of the fuel in the wingborne portion of the platform, and not requiring oxidizer for the wingborne phase of the flight.  (It's not even wingborne during that phase.)

That being said...  A 3,000 pound payload to polar orbit on a rocket "the size of a bizjet"?  Seriously doubtful even without the dead weight of the wings.

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1 hour ago, DerekL1963 said:

It's a winged rocket that flies a powered ballistic trajectory and subsequently lands via aerodynamics, it's not a winged air breather than flies an aerodynamic trajectory.  Therefore it 'solves' most of the problems of air launches by not being an air launch in the first place.  (Or, to put it another way - the problems of air launch comes from being limited to wingborne air breathing altitudes and speeds.)  It also gives away the two advantages that air launch does have...  First by requiring a dedicated vertical launch facility.  Second by carrying a portion of the fuel in the wingborne portion of the platform, and not requiring oxidizer for the wingborne phase of the flight.  (It's not even wingborne during that phase.)

That being said...  A 3,000 pound payload to polar orbit on a rocket "the size of a bizjet"?  Seriously doubtful even without the dead weight of the wings.

No jet engines on it?
if so I agree, now climbing with jet to mach 3 and 18 km then switch to rocket mode to reach mach 6 or more and you are talking, perhaps use the rocket to help takeoff.
Payload and second stage internally, no need for an fairing as you don't open the doors until in space. 

 

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15 hours ago, KerikBalm said:

so... its a winged falcon 9?

With 10% of the payload, for the "paper rocket".  Unless the Air Force project manager decides to throw even goofier requirements to the project than wings.

The interesting bit of the project is similar to what DC-X is said to have pioneered: launching fast and cheap (although I suspect that the ~100 (wasn't it 99?) suborbital flights of the X-15 were wildly cheaper than any other manned rocket.  And neither DC-X nor this were manned).

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On 2017-5-24 at 9:34 PM, StrandedonEarth said:

darpa-boeing-experimental-spaceplane-xs-

Wow, no. This is never gonna happen. Pretty much a rule of thumb: if it's a plane-based concept, it's never gonna get into production. To good to be successful.

Edited by Matuchkin
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29 minutes ago, sevenperforce said:

But if it can't beat a Falcon 9 FT, why bother?

Well, it's always good to have options, not that this is in the same class

I dunno about cryogenics for the booster though. That tends to make things ridiculously big. I also think the upper stage should be more streamlined into the booster. Or take two of the them back-to-backwith a serious core stage in the middle!

 

Edited by StrandedonEarth
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36 minutes ago, sevenperforce said:

But if it can't beat a Falcon 9 FT, why bother?

Because if everyone had that attitude there would only be one car manufacturer, one American fast food restaurant chain, one enormous coffee shop chain and one football team in the world :P 

Edited by Steel
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On 5/27/2017 at 0:30 PM, Steel said:
On 5/27/2017 at 11:53 AM, sevenperforce said:

But if it can't beat a Falcon 9 FT, why bother?

Because if everyone had that attitude there would only be one car manufacturer, one American fast food restaurant chain, one enormous coffee shop chain and one football team in the world :P 

I mean, if it cannot outperform F9FT even on paper, why invest in it?

I wouldn't invest in a fast food restaurant intended to compete with McDs unless it could actually outperform McDs at something.

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28 minutes ago, sevenperforce said:

I mean, if it cannot outperform F9FT even on paper, why invest in it?

I wouldn't invest in a fast food restaurant intended to compete with McDs unless it could actually outperform McDs at something.

It is unwise to let national security interests rest with a single provider. Also, while I doubt this project will be that successful, it might wind up cheaper than Falcon 9. It's hard to tell when the project is so young.

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Also, DARPA exists at least partially to push technological advances and open up new fields previously unexplored. As such they don't operate under as strictly economical requirements as other agencies - not to mention private sector - do.

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This thing is supposed to make 10 orbital launches in 10 consecutive days. But it will only actually carry a second stage payload on the last of those 10 flights. That's because it is a technology development/demonstration tool, not a commercial launcher. DARPA exists to move technologies from low TRLs to medium TRLs, not to compete with existing commercial products.

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For a concept like this, I wonder about the net payload impact of putting an altitude-compensating nozzle on the upper stage so it can fire at launch to improve TWR. Could go either way, I think. I'm a big fan of parallel staging, obviously.

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I would say that the wildcard for this project is DARPA. DARPA projects always seem to be more about pushing the envelope and ignoring traditionalism/traditional constraints. Maybe this program doesn't specifically have an obvious advantage over existing launch vehicles but that doesn't mean that paving the way won't yield something that does.

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On 5/28/2017 at 3:10 PM, Starman4308 said:

It is unwise to let national security interests rest with a single provider. Also, while I doubt this project will be that successful, it might wind up cheaper than Falcon 9. It's hard to tell when the project is so young.

Which is why the Lockheed and Boeing merger of ULA wasn't merely tolerated, but rather it was enabled at all levels of government.

But the better question is what exact natsec launch capability does this design service?

 

And from a technical standpoint, this design is a bad solution to all problems it intends to solve.

Horizontal Landing of boosters was only relevant prior to the Falcon 9, wings are a drag and mass penalty that can now be probably avoided.

Edited by Nothalogh
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