X-37B Orbital Test Vehicle (OTV)

[shedofdread]

Sorry if this is a silly suggestion (space isn't really my field - there's just no atmosphere ) but is it possible that this programme is run to merely maintain a capability against a time when such knowledge will be required again? Albeit at significant cost. Some of that cost may however be defrayed by doing *something* with the platfrom whilst in orbit. Could this explain the lack of financial logic [as apparent to external observers]?

Already getting my coat...

 

[blackstar]

Sorry if this is a silly suggestion (space isn't really my field - there's just no atmosphere ) but is it possible that this programme is run to merely maintain a capability against a time when such knowledge will be required again? Albeit at significant cost. Some of that cost may however be defrayed by doing *something* with the platfrom whilst in orbit. Could this explain the lack of financial logic [as apparent to external observers]?

That's not a silly question.

There is logic to developing these technologies for future use. Off the top of my head there are several technologies incorporated into X-37B:

-new thermal protection systems
-autonomous reentry and landing (essentially they push a button and the thing lands itself)
-autonomous operations in orbit

Although I think technology development is great, this just looks like an expensive way to obtain information that does not have a clear immediate use for the USAF. Okay, autonomous operations can be valuable, but it can also be developed with spacecraft that don't have wings.

One major factor in this equation is that the vehicle has a limited lifetime in orbit. Keep in mind that most satellites last 5-10 years or more. Even if it costs a billion dollars to build a spysat, if it lasts for 10 years that's not a lot of money considering the use that you get from it (and there have been reports of some sigint satellites lasting two decades in orbit). So what is the great value of a spacecraft that is only in orbit for one year? Even if you reuse it, the downtime counts against you--it is time wasted on the ground rather than in orbit doing stuff.

 

[LowObservable]

Blackstar - I'm aware that one-mission sats spend a lot of time on orbit, but part of that is surely a matter of husbanding their non-solar energy very carefully. That's easier to do for passive sensors (EO and SIGINT) than for radar, for example.

Also, before we talk about the payload bay limiting aperture, that's not directly true for SAR, and no longer entirely true for optics:

http://media.al.com/huntsville-times/photo/-8660820da36135fa.jpg

Bay size is related to aperture, but aperture is not limited to bay size.

 

[Hobbes]

One major factor in this equation is that the vehicle has a limited lifetime in orbit. Keep in mind that most satellites last 5-10 years or more. Even if it costs a billion dollars to build a spysat, if it lasts for 10 years that's not a lot of money considering the use that you get from it (and there have been reports of some sigint satellites lasting two decades in orbit). So what is the great value of a spacecraft that is only in orbit for one year? Even if you reuse it, the downtime counts against you--it is time wasted on the ground rather than in orbit doing stuff.

It wasn't too long ago that a spysat had a lifetime measured in months.

The limited on-orbit life can be a problem, but look at it this way: it's a reusable asset that can be launched unpredictably. See it as a replacement for the SR-71. The ability to take at least one look at a target outside the normal scheduled spysat overflights can be valuable.

 

[Byeman]

It launches on an Atlas. That is predicable. It isn't like an SR-71. It is no different than other spysats in this respect.

 

[Byeman]

Blackstar - I'm aware that one-mission sats spend a lot of time on orbit, but part of that is surely a matter of husbanding their non-solar energy very carefully. That's easier to do for passive sensors (EO and SIGINT) than for radar, for example.

Also, before we talk about the payload bay limiting aperture, that's not directly true for SAR, and no longer entirely true for optics:

http://media.al.com/huntsville-times/photo/-8660820da36135fa.jpg

Bay size is related to aperture, but aperture is not limited to bay size.

A small bay and a 500lb capacity is going to limit aperture.


Also, your statement on husbanding resources makes no sense. Non-solar energy means propellant and the sensor type, passive or active has no bearing on this.

 

[blackstar]

It wasn't too long ago that a spysat had a lifetime measured in months.

Yeah, it was only about 25 years ago.

 

[blackstar]

Blackstar - I'm aware that one-mission sats spend a lot of time on orbit, but part of that is surely a matter of husbanding their non-solar energy very carefully. That's easier to do for passive sensors (EO and SIGINT) than for radar, for example.

Uh... what?

That makes no sense at all. Lifetime is not determined by "husbanding non-solar energy" (whatever that is). Lifetime for satellites used to be determined primarily by fuel resources--i.e. when the satellite ran out of fuel (or other consumables) it died. But that's no longer the case. Today lifetime is usually determined by when something breaks.

The Director of the National Reconnaissance Office gave an interview to Aviation Week a month or so ago and was asked about satellite lifetime. I don't have his exact response, but he essentially said that it's determined by different things, presumably for different satellites.

From my own knowledge, optical sensors tend to be vulnerable to radiation. The lifetime for Hubble is not fuel or its gyroscopes or solar power, it is when the instruments burn out due to radiation. A reconnaissance satellite might not have the same vulnerability as the very sensitive instruments on Hubble, but it may be limited by when the sensors degrade/burn out rather than anything else.

 

[Gridlock]

It launches on an Atlas. That is predicable. It isn't like an SR-71. It is no different than other spysats in this respect.

Umm, for the year (or however long it can really go) after the Atlas launch it kind of is like a Blackbird, isn't it? And that's just going on known/informed manoeuvrability capabilities rather than making any fancy guesses about what it launches or recovers or about just how useful those wings are during that year?

 

[LowObservable]

Blackstar - The point is that you design and use satellites to not do high-energy things that can't be powered by solar cells.

The early point of SMV was energy for inspecting satellites, performing flexible recce and strike. Now which, if any of those things are still in the works, I don't know.

 

[blackstar]

Blackstar - The point is that you design and use satellites to not do high-energy things that can't be powered by solar cells.

Um... what?

 

[blackstar]

I found the quote. Aviation Week, November 14, 2011, page 59, in an article titled "Grounded in Space" and featuring an interview with NRO Director Bruce Carlson:

"I will tell you there are very few satellites, very few NRO satellites, that die because they run out of gas. Most of them die for other reasons."

 

[royalistflyer]

The present experimental X-37B launches on a rocket, but is there any reason to believe that a developed version would? What about high altitude aircraft launch? That would mean that it could be launched at any (unpredictable) time. It may act like a satellite in orbit - but it's not intended to do the same job - this vehicle is something sent up for a specific short-term task. And a bigger air-launched one could indeed carry payloads to the ISS or service satellites.

 

[blackstar]

There is a proposal for an X-37C that would be larger. It is not funded.

 

[Hobbes]

The present experimental X-37B launches on a rocket, but is there any reason to believe that a developed version would? What about high altitude aircraft launch? That would mean that it could be launched at any (unpredictable) time. It may act like a satellite in orbit - but it's not intended to do the same job - this vehicle is something sent up for a specific short-term task. And a bigger air-launched one could indeed carry payloads to the ISS or service satellites.

To air-launch the X-37 you need something like the Stratolaunch. If you make the vehicle more than 20% heavier, the carrying aircraft would become too large to launch from existing airports.

The launch would be on an unpredictable schedule, but I suspect it would still be picked up by ICBM detection systems.

 

[LowObservable]

The "high-energy things" include large orbital maneuvers.

At one point in the late 1990s, the goal for the SMV was that it should be able to perform a flyby of a geostationary satellite and then return to LEO.

 

[blackstar]

The "high-energy things" include large orbital maneuvers.

And that has nothing to do with solar cells.

You've really confused the whole thing.

 

[Byeman]

The "high-energy things" include large orbital maneuvers.

At one point in the late 1990s, the goal for the SMV was that it should be able to perform a flyby of a geostationary satellite and then return to LEO.

Not applicable to X-37

 

[Byeman]

The present experimental X-37B launches on a rocket, but is there any reason to believe that a developed version would? What about high altitude aircraft launch? That would mean that it could be launched at any (unpredictable) time. It may act like a satellite in orbit - but it's not intended to do the same job - this vehicle is something sent up for a specific short-term task. And a bigger air-launched one could indeed carry payloads to the ISS or service satellites.

There is no plan for a "developed" one

 

[Byeman]

Blackstar - The point is that you design and use satellites to not do high-energy things that can't be powered by solar cells.
.

That is not a limitation. Solar cells can power any foreseen application wrt active sensing

 

[Byeman]

It launches on an Atlas. That is predicable. It isn't like an SR-71. It is no different than other spysats in this respect.

Umm, for the year (or however long it can really go) after the Atlas launch it kind of is like a Blackbird, isn't it? And that's just going on known/informed manoeuvrability capabilities rather than making any fancy guesses about what it launches or recovers or about just how useful those wings are during that year?

No, it is just like every other satellite

 

[LowObservable]

Byeman and Blackstar - So are we considering the X-37B to be completely pointless? I am seeing a lot of people here just shooting down reasons why it has survived, without advancing any theories of their own.

Now, a lot of programs do survive without a clear mission, but this one doesn't seem to have a lot of service/political push behind it.

 

[blackstar]

Byeman and Blackstar - So are we considering the X-37B to be completely pointless? I am seeing a lot of people here just shooting down reasons why it has survived, without advancing any theories of their own.

I don't think I was unclear in what I wrote, but I'll repeat it: X-37 is confusing. It does not appear to have a clear mission. And it is expensive for an experimental vehicle. And it does not appear to be a stepping-stone to another vehicle.

It may not be "pointless," but it is confusing.

 

[blackstar]

I already posted the first page of this paper on the proposed upgrade to the X-37C. Here are a few more pages. If this forum allowed larger posts, I would post the entire 3 megabyte file at once.

 

[blackstar]

Here is more of the document.

Note: there is no indication that USAF or NASA wants to fund any of this. In fact, probably the most intriguing comment I saw about this was that this might indicate that the program is winding down and therefore Boeing is looking for new business. (That comment was from an outsider, not anybody involved in the program.)

 

[Mat Parry]

The early point of SMV was energy for inspecting satellites, performing flexible recce and strike. Now which, if any of those things are still in the works, I don't know.

Inspecting satelites would appear to be feasible with a 500lb payload, does this fit with current Geopolitics? China are the new kids on the space block, It may be a good idea to keep an eye on their orbital hardware to be sure that they are playing by the old rules of the game regarding weaponisation of space. Forming a view on their spysat capabilities would also be worthwhile (but at the fiscal cost of X37-B)?

 

[Byeman]

The orbits of the X-37 do not coincide with any other spacecraft.


Also, Wings are not needed for such a mission

 

[sferrin]

Byeman and Blackstar - So are we considering the X-37B to be completely pointless? I am seeing a lot of people here just shooting down reasons why it has survived, without advancing any theories of their own.

I don't think I was unclear in what I wrote, but I'll repeat it: X-37 is confusing. It does not appear to have a clear mission. And it is expensive for an experimental vehicle. And it does not appear to be a stepping-stone to another vehicle.

It may not be "pointless," but it is confusing.

Hopefully they're doing something more useful than "let's see how well systems do after X amount of exposure to space. (2nd one is still up there, correct? And does anybody know if/when the first is going back up?) Maybe they're interested in a type of UCAV that can sit up in orbit for long stretches of time and then swoop in and drop a bomb on short notice. i.e. Prompt Global Strike. Then the question is "how quickly can it get to point X considering it has to de orbit" (or at least slow enough so a munition will fall to the ground and then scoot back up). Maybe it slows enough so a munition will fall to the ground and then accelerates back to it's station orbit? Maybe it's an orbital JDAM? Or maybe it's just testing technologies required to implement either of those concepts. Just throwing ideas out there.

 

[Mat Parry]

1 The orbits of the X-37 do not coincide with any other spacecraft.

2 Also, Wings are not needed for such a mission

1 Then we can be sure it hasn't done it's first satelite inspection... yet. OTV-2 has seemed to do less disappearing tricks than OTV-1 (is this why OTV-2 has been up for a significantly longer period of time?)

2 to change orbit (hopefully covertly), loosing the gaze of observers (as OTV-1 did a couple of times with amateur sky watchers) may burn large amounts of fuel. Once all fuel is consumed, a non reusable craft becomes a relic to be burnt up in the atmosphere, wings mean it can be de-orbited and refueled whilst it's twin is launched. (we all seem to keep having this discussion)

I would hope X-37B has a number of capabilities and is just hanging out in orbit waiting to use whichever is required. In the meantime I'm trying to gather information of the orbital changes OTV-1 & 2 made and compare the dates of these with certain "events" back on earth (particularly events in Pakistan), not giving up on the idea its an experimental IMINT platform. As I've said before if OTV-1 & 2 did have a recce payload I can't imagine a higher priority target for when it was in orbit than Abbottabad.

 

[blackstar]

As I've said before if OTV-1 & 2 did have a recce payload I can't imagine a higher priority target for when it was in orbit than Abbottabad.

A stealthy drone would be better. It would provide more than 5 minutes of coverage once per day.

 

[Mat Parry]

As I've said before if OTV-1 & 2 did have a recce payload I can't imagine a higher priority target for when it was in orbit than Abbottabad.

A stealthy drone would be better. It would provide more than 5 minutes of coverage once per day.

Agreed, and it was.

Coverage would be even more fleeting, once every 4 days.

But if you had a experimental spy sat up there, might as well have a look on the off chance? or do you disagree?

 

[blackstar]

Here is the last part of the X-37C paper.

 

[blackstar]

But if you had a experimental spy sat up there, might as well have a look on the off chance? or do you disagree?

Actually, I _do_ disagree. The operation to get Osama bin Laden was very tightly controlled. For something like that I presume that they would only use dedicated assets. It would be risky to take an experimental project, with lots of people who have no clearances for the OBL intelligence gathering operation, and involve them.

 

[archipeppe]

But if you had a experimental spy sat up there, might as well have a look on the off chance? or do you disagree?

Actually, I _do_ disagree. The operation to get Osama bin Laden was very tightly controlled. For something like that I presume that they would only use dedicated assets. It would be risky to take an experimental project, with lots of people who have no clearances for the OBL intelligence gathering operation, and involve them.

I fully agree with Blackstar, takes an experimental project and assign to an operational task it could be likely in an Hollywood movie but not for sure in real life.

 

[cubit]

I haven't seen this asked, but would the wings be helpful were the craft to undertake 'global bounce' manoeuvres like the Silbervogel (http://en.wikipedia.org/wiki/Silbervogel) was proposed to do? I don't know of any research craft designed to utilise this flight regime.

 

[Gridlock]

I haven't seen this asked, but would the wings be helpful were the craft to undertake 'global bounce' manoeuvres like the Silbervogel (http://en.wikipedia.org/wiki/Silbervogel) was proposed to do? I don't know of any research craft designed to utilise this flight regime.

DynaSoar was supposed to. Whatever came after presumably did too, although you'd make one hell of a thermal trail I'd imagine. You'd also need a very good window to take photos out of, although I don't think that's an issue over at NRO any more.

 

[blackstar]

I haven't seen this asked, but would the wings be helpful were the craft to undertake 'global bounce' manoeuvres like the Silbervogel (http://en.wikipedia.org/wiki/Silbervogel) was proposed to do? I don't know of any research craft designed to utilise this flight regime.

DynaSoar was supposed to. Whatever came after presumably did too, although you'd make one hell of a thermal trail I'd imagine. You'd also need a very good window to take photos out of, although I don't think that's an issue over at NRO any more.

That also raises the question of the value of such a maneuver. Why bounce off the atmosphere at all? Seems like it adds complication and risk. Just go a little higher and you don't have to do that kind of thing.

 

[antigravite]

That also raises the question of the value of such a maneuver. Why bounce off the atmosphere at all? Seems like it adds complication and risk. Just go a little higher and you don't have to do that kind of thing.

Interesting subject, indeed. This relates to "synergetic or atmospheric plane change". In the early / mid 1980s, there were some interesting studies (Nasa Ames, Rockwell) of winged aerospace reentry vehicle concepts, launched back to Earth from orbit, from the space shuttle payload bay. Concepts such as the ERV (Entry Research Vehicle) among others. Studies were led, mostly, by Delma C. Freeman, Christ Naftel, Richard W. Powell, etc. USAF also handled some studies but it's pretty old stuff and my memory falls short here. Have to look back in my archives.


Hope this helps.

 

[Nik]

"Why bounce off the atmosphere at all?"

Lift !!

Plane changes in orbit need a heap of fuel, but a single hypersonic skip can swing through a dozen degrees using comparatively low fuel expenditure at start and end of manoeuvre.

 

[Byeman]

The issue is why is a plane change needed for a low orbiting spacecraft. After all, most use sun synchronous orbits.