X-37B Countdown and Launch

[stutefish]

Instead of repeating the Shuttle's mistake of wasting 70% of your useful payload on the ability to return an empty glider, why not simply use JPADS technology so that we can land the astronauts on dry ground? With surface and winds at 100', 200', and 300' beamed to the craft's onboard computer, you can make a perfect approach and touch down light as a feather. We shouldn't haul up any more than what's required to get the payload to it's intended orbit.

I can guess at four reasons why JPADS isn't used:

One, it may not be practical at orbital reentry velocities. Most military supply drops come from large cargo planes at much lower altitudes and subsonic speeds.

Two, it may not be economically practical for NASA. The military's mission requires it to spend whatever blood or treasure it takes to get the job done. If a battle can be won, or a war can be shortened, by using a hideously expensive delivery system, then it makes sense to use a hideously expensive delivery system. NASA, having to make a totally different set of tradeoffs, may have found that their non-military objectives can be met more cheaply by other means.

Three, JPADS may not actually offer a significant mass savings. What costs you more in lost payload? An empty glider reentry vehicle, or a JPADs reentry system? Especially after you've beefed it up to the point where it can handle atmospheric reentry?

I mean, JPADS is a cargo bay, a steerable airfoil, and a guidance computer. And the X-37 is a cargo bay, a steerable airfoil, and a guidance computer--that can land from orbit.

[publiusr]

An orbiter of some size is useful in station construction. With a 90-100 ton orbiter wrangling a 20 ton payload, the dog is still wagged the tail and not vice versa. I don't mind a big orbiter--as long as its Buran...

Strafing, molasses speed? ouch..

[stutefish]

An orbiter of some size is useful in station construction. With a 90-100 ton orbiter wrangling a 20 ton payload, the dog is still wagged the tail and not vice versa. I don't mind a big orbiter--as long as its Buran....

I think this idea makes more sense down here, where the "wrangler" is braced against the ground, and can use its larger mass to good effect.

Up there, it's all just mass, and there's nothing to brace against. Why spend reaction fuel to keep the orbiter on station along with the payload? Why not just strap a maneuvering cluster to the payload and omit the "wrangler" altogether? And if you can't omit the wrangler, why not go for the smallest wrangler possible, to reduce the overall mass you need to wrangle?

[Nicolas]

An orbiter of some size is useful in station construction. With a 90-100 ton orbiter wrangling a 20 ton payload, the dog is still wagged the tail and not vice versa. I don't mind a big orbiter--as long as its Buran...

Strafing, molasses speed? ouch..

They'd have to build a new one, as last time I checked, all the Buran type orbiters were damaged or completely destroyed. Which is a pity, if only for historical reasons.

[publiusr]

Maybe China will bring the idea back.

Maybe, in some alternate universe, it was the USA that invented Buran (Snowstorm).

EELV/Zenit strap-ons,, an HLLV core block, and an orbiter that was just another payload that could be exchanged.

Space construction may have to wait until OMVs finally fly.

[01101001]

Links:
NASA Marshall Spaceflight Center: X-37 News (currently, very old news)
NASA Launch Schedule
National Weather Service, Southeast Sector, Base Reflectivity
National Weather Service, Melbourne Florida, Hourly Weather Forecast Graph
Wikipedia: Boeing X-37
Wikipedia: X-37B OTV-1
Space.com: Air Force's Secretive Space Plane Nears Maiden Voyage
BAUT Forum topic Look familar? (some recent discussion)

Spaceflight Now Launch Schedule:

Launch target:
2010, April 19, time TBD PDT, Monday
2010, April 19, time TBD EDT, Monday
2010, April 19, time TBD UTC, Monday

About 3-1/2 months to launch

[01101001]

Spaceflight Now Launch Schedule:

4-hour launch window opens:
2010, April 19, 1900 PDT, Monday
2010, April 19, 2200 EDT, Monday
2010, April 20, 0200 UTC, Tuesday

About 6 weeks to launch

[Parallax M86]

Hmm. It kind of reminds me of the X-20 Dyna-Soar idea and the MiG-105 Spiral idea. Except now it's actually real! :surprised

Can't wait for the launch.

[mugaliens]

Maybe, in some alternate universe, it was the USA that invented Buran (Snowstorm).

You mean we didn't? Please confirm that JFK Jr. is still president...

[The Jim]

Hmm. It kind of reminds me of the X-20 Dyna-Soar idea and the MiG-105 Spiral idea. Except now it's actually real! :surprised

Can't wait for the launch.

It won't be any different than other classified launches. The X-37 will be inside the fairing and won't be visible. Landing might not even be televised.

[Parallax M86]

It won't be any different than other classified launches. The X-37 will be inside the fairing and won't be visible. Landing might not even be televised.

Aww. That sucks.

[01101001]

4-hour launch window opens:
2010, April 19, 1900 PDT, Monday
2010, April 19, 2200 EDT, Monday
2010, April 20, 0200 UTC, Tuesday

1 month to launch

[Gemini]

I think it's still cool that we have a winged space transport.

[mugaliens]

I can guess at four reasons why JPADS isn't used:

One, it may not be practical at orbital reentry velocities. Most military supply drops come from large cargo planes at much lower altitudes and subsonic speeds.

It's not the initial chute, stutefish. In fact, they'd be the third. The first would be a high-altitude stabilization chute, possibly unnecessary if the payload is dynamically stable throughout reentry. The second would be deployed somewhere between 30k ft and 60k ft to slow the payload to 130 kts, and the final chutes would be the JPADs chutes, the largest of which is currently capable of i.e. has successfully handled 60,000 lb payloads.[/quote]

Two, it may not be economically practical for NASA. The military's mission requires it to spend whatever blood or treasure it takes to get the job done. If a battle can be won, or a war can be shortened, by using a hideously expensive delivery system, then it makes sense to use a hideously expensive delivery system. NASA, having to make a totally different set of tradeoffs, may have found that their non-military objectives can be met more cheaply by other means.

Non-sequitor. Chutes are both lightweight and cheap. Winged reentry vehicles are neither.

Three, JPADS may not actually offer a significant mass savings. What costs you more in lost payload? An empty glider reentry vehicle, or a JPADs reentry system?

An empty glider, like by a factor of five, even over a three-chute system.

I mean, JPADS is a cargo bay...

Not from orbit. From orbit it's simply a heat shield.

...a steerable airfoil...

About 200-500 lbs, depending on payload.

...and a guidance computer.

That would be a 6.7 lb Panasonic Toughbook! The computer aboard the payload is actually lighter, including the GPS. The actuation mechanism to steer the chutes adds a few more pounds, but the entire system guidance system weighs less than 30 lbs.

...And the X-37 is a cargo bay, a steerable airfoil, and a guidance computer--that can land from orbit.

And weighs what? 30,000 lbs? 50,000 lbs?

[Sardonicone]

It seems a rather small vehicle to weight 15 to 25 tons. I'll have to look it up to see if we can get some accurate specs concerning mass.

X-37B wiki


I'm showing a mass of ~6 tons. They're using an Atlas V for the launch, so I suppose it's possible to have it weigh ~32 tons, but not sure you can have a 26 ton payload put into the vehicle.

[The Jim]

Atlas V 501 can only lift 18Klb due east.

[NEOWatcher]

Atlas V 501 can only lift 18Klb due east.

Why do you say that?
Do we know what the final launch configuration will be?

[djellison]

That's the performance of the launch vehicle
http://docs.google.com/viewer?a=v&q=...r_FBStYbFqsDmg

Page 17.

I really wonder what they're putting in the payload bay (and how much the entire exercise is costing)

[NEOWatcher]

I really wonder what they're putting in the payload bay (and how much the entire exercise is costing)

I can see what the various Atlas configurations payloads are.
My point is what is the final configuation of an X-37B launch?

[ugordan]

My point is what is the final configuation of an X-37B launch?

Atlas V 501 as already said. Hence it also puts an upper limit on spacecraft mass, which was (erroneously) speculated above to be in excess of 10 tons.

[NEOWatcher]

Atlas V 501 as already said. Hence it also puts an upper limit on spacecraft mass, which was (erroneously) speculated above to be in excess of 10 tons.

No; I said final configuration.

This is a test flight, this craft is a prototype.

The next one is to be strengthened, but I haven't heard about a launch vehicle. Besides, that's still a test.

But; whose to say that it isn't destined for a 551 as an end product.

[The Jim]

No; I said final configuration.

This is a test flight, this craft is a prototype.

The next one is to be strengthened, but I haven't heard about a launch vehicle. Besides, that's still a test.

But; whose to say that it isn't destined for a 551 as an end product.

The X-37 is only a test vehicle and much like the X-15. It is not a prototype for an operational mission of the same vehicle, it is in its "final configuation". There is not going to be a production of this specific vehicle.

The payload bay of the X-37 can only carry 500 lbs.

[NEOWatcher]

The X-37 is only a test vehicle and much like the X-15. It is not a prototype for an operational mission of the same vehicle, it is in its "final configuation". There is not going to be a production of this specific vehicle.

The payload bay of the X-37 can only carry 500 lbs.

Yes that's pretty much my point. Follow the original statements and you'll see that my question was in relation to your response of what's possible. Not necessarily this vehicle.
Although; there was a lot of bantering about this particular vehicle too. So; I can see how we went two seperate ways.

[The Jim]

Yes that's pretty much my point. Follow the original statements and you'll see that my question was in relation to your response of what's possible. Not necessarily this vehicle.
Although; there was a lot of bantering about this particular vehicle too. So; I can see how we went two seperate ways.

nor is it a prototype of any larger vehicle to fly on EELV's

[01101001]

AP: Air Force to launch robotic winged space plane

"As long as you're confused you're in good shape," said defense analyst John Pike, director of Globalsecurity.org. "I looked into this a couple of years ago — the entire sort of hypersonic, suborbital, scramjet nest of programs — of which there are upwards of a dozen. The more I studied it the less I understood it."

The mission's length was not released but the Air Force said the X-37B can stay in orbit for 270 days. The primary landing site will be northwest of Los Angeles at coastal Vandenberg Air Force Base.
The significance of the X-37B is unclear because the program has been around for so long, said Peter A. Wilson, a senior defense research analyst for the RAND Corp. who several years ago served as executive director of a congressional panel that evaluated national security space launch requirements.
"From my perspective it's a little puzzling as to whether this is the beginning of a program or the end of one," Wilson said Friday in a telephone interview from Washington, D.C.

Wilson sees the upcoming launch as "a one-shot deal."
He acknowledged that he does not know if there is a classified portion of the program but said there is no evidence of a second vehicle being built to follow the prototype. In aerospace, a prototype typically remains a test vehicle used to prove and improve designs for successive operational vehicles.

4-hour launch window opens:
2010, April 19, 1900 PDT, Monday
2010, April 19, 2200 EDT, Monday
2010, April 20, 0200 UTC, Tuesday

About 15 days to launch

[mugaliens]

Amazingly shrouded in secrecy...

[slang]

"As long as you're confused you're in good shape". A keeper.

[01101001]

Space.com launch schedule:

April 19: A space plane prototype for the U.S. military called Orbital Test Vehicle (OTV) to launch atop a United Launch Alliance Atlas 5 rocket on a test flight from Cape Canaveral Air Force Station in Florida. 6:49 - 9:12 p.m. EDT (2249-0112 GMT).

3-1/2-hour launch window opens:
2010, April 19, 1549 PDT, Monday
2010, April 19, 1849 EDT, Monday
2010, April 19, 2249 UTC, Monday

6 days, 21 hours to launch

Or...

Spaceflight Now launch schedule

Launch window: 2246-0110 GMT on 20th-21st (6:46 p.m.-9:10 p.m. EDT on 20th)

7 days, 21 hours to launch

[mugaliens]

"As long as you're confused you're in good shape". A keeper.

Lol, thanks! I think I'll keep myself as I am confused about this program, particularly why the Air Force took it over.

[Craigboy]

Lol, thanks! I think I'll keep myself as I am confused about this program, particularly why the Air Force took it over.

Popular Science has an interesting article about why.