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Author
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Topic: [Discuss] USAF X-37B Orbital Test Vehicle
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Robert Pearlman
Editor Posts: 51581
From: Houston, TX
Registered: Nov 1999
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posted 04-23-2010 12:00 PM
   
Please use this topic to discuss the U.S. Air Force's X-37B fleet of orbital test vehicles and their flights. |
hlbjr
Member Posts: 566
From: Delray Beach Florida USA
Registered: Mar 2006
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posted 04-23-2010 12:44 PM
The launch was stunning to see from 155 miles south in Lantana Florida. I've never seen a launcher climb quite the way this one did and it was clearly visible the whole time. The fairing separation was clearly visible and the two falling segment halves looked just like stars falling and seemed so bright that I couldn't believe they were just reflecting sunlight. I could also clearly see the payload support structure which fell away not too long after fairing separation and it too was bright. The most amazing aspect of the launch (other than how high we had to crane our necks to track it) was how big the rocket plume became in the vacuum of space. Even the RL-10 plume was clearly visible. The old fisherman gutting a fish next to me watched mesmerized as I described what was happening. He said he'd never seen anything like it in all his days here in South Florida. I wish I could watch that launch live over and over again. |
albatron
Member Posts: 2804
From: Stuart, Florida
Registered: Jun 2000
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posted 04-23-2010 03:59 PM
It caught me by surprise. I was the designated pizza retriever, and as I came out it was clearing the trees (100 miles south in Stuart). The time of day assisted in the viewing, not dark but the sun had begun to set. One of the better views. |
cspg
Member Posts: 6358
From: Geneva, Switzerland
Registered: May 2006
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posted 12-03-2010 02:35 PM
So when NASA is ending its shuttle program (or told to do so) the Air Force is starting its own. Ironic. |
onesmallstep
Member Posts: 1434
From: Staten Island, New York USA
Registered: Nov 2007
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posted 12-03-2010 04:04 PM
Actually, the X-37B started life as a NASA program. It was originally meant to go up in the shuttle's cargo bay; it was later modified so that a Delta II could launch it. When NASA funding ran out in 2004, it was handed over to DARPA, and ultimately, in 2006, to the Air Force. But yes, just as one winged reusable reentry vehicle is retiring, another comes along. Maybe they can man-rate the X-37 eventually? |
gliderpilotuk
Member Posts: 3415
From: London, UK
Registered: Feb 2002
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posted 12-03-2010 04:15 PM
So, presumably the first fully-automated re-entry and landing of a winged vehicle since Buran 22 years ago? Makes this achievement even more remarkable. |
328KF
Member Posts: 1391
From:
Registered: Apr 2008
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posted 12-03-2010 04:54 PM
In the words of Scott Crossfield, "If you're not going to put a man in it, what's the point?"For the cloak and dagger types, and maybe the RC airplane crowd, this is super cool, but for those who are looking to see the expansion of man into the solar system, well... Just another Predator with a higher perch. |
Robert Pearlman
Editor Posts: 51581
From: Houston, TX
Registered: Nov 1999
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posted 12-03-2010 05:04 PM
While unmanned and without exploration as one of its objectives, the X-37B is a technology demonstrator and development platform. Its ability to land autonomously, if proven over multiple flights, could easily benefit future piloted vehicles, making the next generation of space planes and shuttles safer for all involved. |
kr4mula
Member Posts: 642
From: Cinci, OH
Registered: Mar 2006
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posted 12-06-2010 11:52 AM
Robert's right. Even though this is a tech demonstrator, this type of vehicle when operational would be doing pretty much things that are done by other unmanned means now: satellite deployment (and retrieval?), perhaps cargo delivery, and reconnaisance. By routinizing and economizing those tasks, it frees up money and focus for manned flights to do the exploring that man does best. The X-37B, ironically, is also the type of risk-reduction activity that would've benefited the shuttle development and perhaps really should have preceded it. |
328KF
Member Posts: 1391
From:
Registered: Apr 2008
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posted 12-06-2010 04:02 PM
Okay, take a look at the vehicle, particularly the wings. What do they look like? That's right, they are nearly identical to the 1970's era space shuttle wings. Virtually the same lift to drag and crossrange. Nothing new there, just scaled down.Now, the autoland capability. The shuttle has had this since very early in the program, and every re-entry has been flown by the onboard computers, then taken over by the CDR once subsonic. The system is designed to land autonomously, but what pilot in that seat would let it? Almost every commercial airliner in service today has some form of autoland capability and has since the 70's. Such systems can fly you to down to a runway in 0/0 weather and bring you to a complete stop on the centerline. Nothing new there. The thermal protection system is somewhat advanced over the shuttle tile, but verification of a new tile does not in itself justify an expensive flying testbed. So what are we left with? A "rapid response capable" and highly unpredictable (from the bad guys' point of view)spy satellite. The real technology testing and development that will be done with this system is that done in the payload bay, with all of the classified sensors or whatever else they fill it with. The military will learn alot about how to best operate this type of system to our advantage. And this knowledge won't be shared with anyone, nor should it. It's a great asset for the U.S. military and will likely save alot of lives, but the X-37 was orphaned by NASA because it "no longer fit the agency's exploration goals." Now that it is in the classified world, and funded by DoD (not NASA), I would think that any lessons learned, even if they are applicable, will be very difficult to get out and be of any benefit to civilian manned space exploration or tourism. |
Jim Behling
Member Posts: 1855
From: Cape Canaveral, FL
Registered: Mar 2010
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posted 12-06-2010 06:59 PM
quote:
Originally posted by 328KF:
A "rapid response capable" and highly unpredictable (from the bad guys' point of view) spy satellite.
It is neither of these things. Its prep time is on the order of a few months and so is its launch vehicle. It is no more "unpredictable" than any other spacecraft with a large propellant system.500lb payload is small, especially for recon. This vehicle is not going to "save lives." |
328KF
Member Posts: 1391
From:
Registered: Apr 2008
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posted 12-06-2010 10:13 PM
The project is being run by the Air Force Rapid Capabilities Office. I think "rapid" is quite a relative term when it comes to space operations. The X-37B's reusability makes it's turnaround much more "rapid" than funding and building a new small satellite every time a new conflict flares up in some country the U.S. would like to monitor.One only needs to look at the "lost and found" game during this test flight as an example of how unpredictable a short mission duration spacecraft can be. Most of the bad guys don't have sophisticated means of tracking foreign satellites, and if they rely on some amatuer skywatchers, the limitations are obvious. This too may be another reference to the "rapid response"...having such an asset available in orbit that can be quickly moved to put it over a target at a required time. This particular ship may not be or become an operational intelligence gathering platform, but the technologies being developed in it's payload bay might someday actually do the life saving I mentioned. Anyway, it's just opinion from me. We have no way of knowing what the military plans are for this thing. My main reason for the original post was to point out what it wasn't. |
Delta7
Member Posts: 1746
From: Bluffton IN USA
Registered: Oct 2007
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posted 12-07-2010 07:36 AM
quote:
Originally posted by 328KF:
We have no way of knowing what the military plans are for this thing.
If the past is any indication, spend a few billion dollars then cancel it.  |
Jim Behling
Member Posts: 1855
From: Cape Canaveral, FL
Registered: Mar 2010
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posted 12-07-2010 08:01 AM
quote:
Originally posted by 328KF:
...building a new small satellite every time a new conflict flares up in some country the U.S. would like to monitor.
The US does not need to put "new" or even "small" satellites up for every conflict. Existing assets can provide the coverage. quote:
One only needs to look at the "lost and found" game during this test flight as an example of how unpredictable a short mission duration spacecraft can be.
It was never "lost." Only the amateur skywatchers lost it. And they found it quickly. quote:
...having such an asset available in orbit that can be quickly moved to put it over a target at a required time.
You don't understand orbital mechanics. It can't be quickly moved over a target. That is a fallacy. quote:
This particular ship may not be or become an operational intelligence gathering platform, but the technologies being developed in it's payload bay might someday actually do the life saving I mentioned.
There are small experimental spacecraft that are launched all the time that do the same thing. X-37 provides no real advantage over them. |
SpaceAholic
Member Posts: 5311
From: Sierra Vista, Arizona
Registered: Nov 1999
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posted 12-07-2010 08:34 AM
quote:
Originally posted by Jim Behling:
The US does not need to put "new" or even "small" satellites up for every conflict. Existing assets can provide the coverage....you don't understand orbital mechanics. It can't be quickly moved over a target. That is a fallacy.
Without getting into the merits of the X-37B specifically, operationally responsive space launch and the ability to orbit on demand payloads is a DOD requirement (in part because your latter point invalidates the first). Battlefield commanders require tactical level control of persistant overhead reconnaissance and communications assets - orbital placement, capacity, and capability weighed against other competing national priorities for the same resources are often in-congruent with warfighter needs to achieve information dominance within his respective area of responsibility (AOR). A second rational is continuity of government and reconstitution of essential services (there are a slew of man made and natural environmental effects that can disable or outright kill our birds). |
Jim Behling
Member Posts: 1855
From: Cape Canaveral, FL
Registered: Mar 2010
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posted 12-07-2010 11:09 AM
quote:
Originally posted by SpaceAholic:
Battlefield commanders require tactical level control of persistant overhead reconnaissance and communications assets -
And an ORS can not provide the persistence, which is its main fallacy. Persistence for comm or signint requires GEO/GSO orbits. Persistent recon requires more than the first pass of ORS spacecraft that won't be back over the site for a day. Hence UAV's are in vogue of all these roles. |
butch wilks
Member Posts: 336
From: Lowestoft, Suffolk, UK
Registered: Mar 2007
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posted 12-07-2010 12:40 PM
As to knowing what the military plans are for the X-37B, all we have to do is wait for Wikileaks to put it on the web, and we'll all know then. |
SpaceAholic
Member Posts: 5311
From: Sierra Vista, Arizona
Registered: Nov 1999
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posted 12-07-2010 02:56 PM
quote:
Originally posted by Jim Behling:
And an ORS can not provide the persistence, which is its main fallacy. Persistence for comm or signint requires GEO/GSO orbits.
Nothing in my comment excluded GEO/GSO however a non GEO/GSE multi-satellite constellation can achieve the same effect (the most extreme example of this is GPS and Iridium); as few as a three bird constellation in a Molniya orbit can provide a comparable degree of persistent coverage. |
gliderpilotuk
Member Posts: 3415
From: London, UK
Registered: Feb 2002
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posted 12-07-2010 03:14 PM
quote:
Originally posted by butch wilks:
As to knowing what the military plans are for the X-37B, all we have to do is wait for Wikileaks to put it on the web, and we'll all know then.
Yeah, bring it on...
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dom
Member Posts: 1063
From:
Registered: Aug 2001
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posted 12-07-2010 03:34 PM
Maybe the X-37B was put into orbit to find Julian Assange! |
Jim Behling
Member Posts: 1855
From: Cape Canaveral, FL
Registered: Mar 2010
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posted 12-07-2010 07:01 PM
quote:
Originally posted by SpaceAholic:
(the most extreme example of this is GPS and Iridium); as few as a three bird constellation in a Molniya orbit can provide a comparable degree of persistent coverage.
None of which are achievable through a few ORS launches and Molniya orbit comsats are not usable in the field. |
SpaceAholic
Member Posts: 5311
From: Sierra Vista, Arizona
Registered: Nov 1999
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posted 12-07-2010 07:34 PM
The Russians have routinely employed satellites in Molniya orbits for comms - the physics doesn't change once the border is crossed. |
cspg
Member Posts: 6358
From: Geneva, Switzerland
Registered: May 2006
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posted 03-06-2011 08:37 AM
Rats! The video ends just before the fairing being jettisoned...Atlas is a really nice looking vehicle (compared to Delta 4). Quite a big fairing too. |
jasonelam
Member Posts: 695
From: Greensburg, KY USA
Registered: Mar 2007
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posted 03-07-2011 11:55 AM
Out of curiousity, what is the "antenna" poking out of the fairing in the above photo? I noticed in the video of the launch and hadn't seen it before. |
Ben
Member Posts: 1926
From: United States
Registered: May 2000
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posted 03-07-2011 12:34 PM
That is the Centaur purge line. It is hooked up to an umbilical on the tower before launch. |
Cozmosis22
Member Posts: 1115
From: Texas * Earth
Registered: Apr 2011
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posted 08-24-2011 03:57 PM
So what is the X-37B doing when it flies?Maybe it returns HD video and still imagery of other countries' spacecraft? If so, then it's a worthwhile USAF venture.  |
cspg
Member Posts: 6358
From: Geneva, Switzerland
Registered: May 2006
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posted 11-30-2011 08:20 AM
OTV-2 is still in orbit and mission has been extended. |
Jim Behling
Member Posts: 1855
From: Cape Canaveral, FL
Registered: Mar 2010
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posted 11-30-2011 08:24 AM
quote:
Originally posted by SpaceAholic:
The Russians have routinely employed satellites in Molniya orbits for comms - the physics doesn't change once the border is crossed.
They weren't used for battlefield comm and they require the ground station to have tracking antennas. |
gliderpilotuk
Member Posts: 3415
From: London, UK
Registered: Feb 2002
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posted 01-05-2012 07:29 AM
America's classified X-37B spaceplane is probably spying on China, according to a report in Spaceflight magazine. "Space-to-space surveillance is a whole new ball game made possible by a finessed group of sensors and sensor suites, which we think the X-37B may be using to maintain a close watch on China's nascent space station," said Spaceflight editor Dr David Baker. |
cspg
Member Posts: 6358
From: Geneva, Switzerland
Registered: May 2006
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posted 01-05-2012 07:51 AM
If true, how close could a spacecraft come to another one before triggering an international/spatial incident? On Earth we have borders, but in space? |
Glint
Member Posts: 1119
From: New Windsor, Maryland USA
Registered: Jan 2004
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posted 01-05-2012 08:20 AM
According to heavens-above.com, their inclinations are similar, though not as similar as described in the article where the difference was said to be only 0.01° degree. (The article gives 42.78° as the inclination of Tiangong-1, and 42.79° for X-37B). Here are their inclinations as given by heavens-above.com: 42.7875° - Tiangong 1
42.4533° - X-37B And when I just checked the position of each on heavens-above.corm, Tiangong 1 was in the middle of the south Atlantic Ocean and Tiangong 1 was crossing the western coast of Australia. So they were hardly within sight of one another. However, as the article says, by varying elements of its orbit that affect the period, the separation distance can be made to change over time. It will be interesting to see how the relative orbits change when the next Shenzhou missions are launched. Added note: Looking at the bigger picture. The 40°57′38″N Latitude of the Jiuquan Satellite Launch Center places itself, and presumably any payload launched from there, within the same Latitude band spanned by X-37B's orbit (although maximum inclination for launches from there is said by some sources to be as high as 56°.) |
Glint
Member Posts: 1119
From: New Windsor, Maryland USA
Registered: Jan 2004
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posted 01-05-2012 08:28 AM
quote:
Originally posted by cspg:
If true, how close could a spacecraft come to another one before triggering an international/spatial incident? On Earth we have borders, but in space?
According to heavens-above.com the apogee of X-37B lies 15 km beneath the perigee altitude of Tiangong 1. So even at the worst case of the vehicles themselves crossing paths they should come no closer than that. So there should be no fears of a collision. Space junk near misses come much closer than that. As far as their other fears go, I could not say. |
Hart Sastrowardoyo
Member Posts: 3469
From: Toms River, NJ
Registered: Aug 2000
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posted 01-05-2012 09:33 AM
quote:
Originally posted by cspg:
If true, how close could a spacecraft come to another one before triggering an international/spatial incident? On Earth we have borders, but in space?
What's the minimum separation distance between airplanes? Wouldn't that be used as precedent? |
ilbasso
Member Posts: 1527
From: Greensboro, NC USA
Registered: Feb 2006
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posted 01-05-2012 09:48 AM
Given that the X-37B was launched in March and Tiangong-1 went up in September in a similar orbital plane, isn't it just as likely that Tiangong-1 was sent up to spy on the X-37B? I suppose the X-37B can change its orbital plane in flight, but that requires a large expenditure of fuel. I haven't gone back to check if any of its orbital parameters have changes since launch, other than periodic re-boosts. I don't doubt that surveillance is part of the X-37B's mission, but I think that concluding that its sole purpose is to spy on Tiangong by making an approach every 170 orbits is a bit of a stretch. There's a lot of stuff that Tiangong can be doing in the other 169 orbits when it's not being approached by the X-37B. |
cspg
Member Posts: 6358
From: Geneva, Switzerland
Registered: May 2006
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posted 01-07-2012 03:03 PM
A Space.com article claims that the X-37B couldn't observe because it's going too fast relative to its target, Tiangong, - 7km per second. So spy satellites, also traveling at the same speed, can't take pictures of earthly targets? However, the orbits of the X-37B and Tiangong 1 differ greatly — by about 100 degrees — in a parameter called right ascension, which describes where a craft crosses the equator, Weeden said. So the two satellites actually take disparate paths around the globe, with their orbits intersecting just twice per circuit.That means that the X-37B and Tiangong 1 could theoretically approach each other a maximum of two times per orbit, if the timing works out perfectly. And even then, they'd scream past each other at very high speeds — not exactly optimum conditions for a spy mission. |
Michael Davis
Member Posts: 566
From: Houston, Texas
Registered: Aug 2002
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posted 02-23-2012 02:31 PM
I have wondered whether the X-37B could be quickly fitted for a crew. It has shown reliability at this point and one would guess that there is enough room available to pack in an oxygen tank or two for a crew. That is a simplification of course, but a Mercury capsule was pretty simple in terms of the environmental support system and that is the level of crew comfort and safety that I am thinking about.Does anyone know enough about the X-37B to either support or crush my idle speculation on crewing an X-37B in an emergency? |
cspg
Member Posts: 6358
From: Geneva, Switzerland
Registered: May 2006
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posted 02-23-2012 02:32 PM
The X-37 is launched inside a payload fairing. The crew would have to wait for days inside the X-37 before being launched. I guess a lot of upgrades would be needed! |
Michael Davis
Member Posts: 566
From: Houston, Texas
Registered: Aug 2002
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posted 02-24-2012 01:08 PM
I suspect that the full force of the United States Air Force could mange to cut a hole in the fiberglass fairing.  I am more curious about whether the vehicle itself could be modified for a crew. |
Jim Behling
Member Posts: 1855
From: Cape Canaveral, FL
Registered: Mar 2010
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posted 02-24-2012 01:18 PM
quote:
Originally posted by Michael Davis:
Specifically I have wondered whether the X-37B could be quickly fitted for a crew.
No, it does not have the capability. It can only carry 500lbs of payload and it is not have a pressurized compartment. Payload bay (3.3" diameter by 7') must be open on orbit to reveal the radiators and to allow the solar array to deploy. |
kr4mula
Member Posts: 642
From: Cinci, OH
Registered: Mar 2006
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posted 02-27-2012 12:00 PM
As the previous commenter said, the X-37B has a limited payload, so it would be tough to provide a miniature environmental control system within those parameters. However, maybe you could put the guy in an EMU with some sort of extended-use PLSS and inside a payload bay pod of some sort. But I can't imagine what sort of mission this could serve. |
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