Missing: One Hypersonic Glider (again?)

[NEOWatcher]

We talked about the first one...

It seems we may have a repeat.
New York to LA in less than 12 minutes

Update 12:29pET- DARPA says it could not regain contact with HTV2 but the hypersonic wedge can terminate its flight autonomously.
Update 11:23aET – DARPA has lost contact with the HTV2
Update 10:57aET – DARPA: Entering "glide phase", maneuvering to test the aerodynamic aspects. Mission is "on track"

[Zvezdichko]

Why am I not unhappy? Hm... let me guess, because it's military spacecraft...

[Solfe]

"...the hypersonic wedge can terminate its flight autonomously."

For some reason, I can picture Marvin the Paranoid android at the controls pressing a bright red button.

[sts60]

Why am I not unhappy? Hm... let me guess, because it's military spacecraft...

Ironically, the same folks behind this technology are the same ones behind the invention of the Internet, which allowed you to share the above opinion.

[Zvezdichko]

I know this, as well as I perfectly know that ballistic rockets have been developed for military purposes. Still, this is illogical aversion that's hard for me to overcome.

[slang]

I know this, as well as I perfectly know that ballistic rockets have been developed for military purposes. Still, this is illogical aversion that's hard for me to overcome.

Overcome it, or don't. Just understand that whatever breakthroughs are made will soon find their way into commercial applications. Of course your mileage may vary on the "soon" part, and commercial exploitation may prove impossible.

[Extravoice]

This proves that hypersonic gliding is impossible, and the whole Space Shuttle program was faked!

Oh, wait a minute, this isn't the Conspiracy Theory forum.
Nevermind.
(Yes, I was kidding!)

More seriously, I hope the thing was riddled with telemetry sensors and had lots of downlink bandwidth.
Maybe something important can be learned from the loss.

[ravens_cry]

Indeed. In science and engineering, a failure can teach as much, or more, than success.

[Gsquare]

"...the hypersonic wedge can terminate its flight autonomously."

.

So lets see; I guess this means it can annihilate itself automatically so no one is able to get the secrets.??

)

[Gsquare]

We talked about the first one...

It seems we may have a repeat.
New York to LA in less than 12 minutes

WOW! 13,000 mph.?....that's pretty awesome.
12 minutes coast to coast....? Unbelieveable.

However, if you want the capability to reach any point on the globe in less than 60 minutes, wouldn't it be easier just to orbit the dang thing, and de-orbit upon the target?

Or how about simply keeping a few loads of weapons orbiting up there and simply de-orbit them upon the enemy at will.? Oh yeah, we already have that.
I guess we're trying to deploy a few Navy seals to the next Bin Laden roof top without having to use those dang helicopters. )

Gsquare

[ravens_cry]

So lets see; I guess this means it can annihilate itself automatically so no one is able to get the secrets.??

)

That and so it doesn't land in someone roof at near orbit velocity.

[Polyrealastic Observer]

That animation showed a LOT of maneuvering (It seemed that way to me, anyway). I wonder if there is really that much.

[Gsquare]

That and so it doesn't land in someone roof at near orbit velocity.

Yeah, or flings itself into orbit where no one can recover it. Seems like it has enough velocity to go orbital if aimed in the right direction . Nah, probably just short of necessary orbital velocity.

G^2

[Grashtel]

Yeah, or flings itself into orbit where no one can recover it. Seems like it has enough velocity to go orbital if aimed in the right direction . Nah, probably just short of necessary orbital velocity.

G^2

Even if it did have enough velocity to make it into orbit it wouldn't stay there for long as without the capability to make a circularizing burn its perigee would be in the atmosphere causing rapid decay of its orbit.

[joema]

...if you want the capability to reach any point on the globe in less than 60 minutes, wouldn't it be easier just to orbit the dang thing, and de-orbit upon the target?

Orbital space weapons are prohibited by the 1967 Outer Space Treaty http://en.wikipedia.org/wiki/Outer_Space_Treaty , if they use weapons of mass destruction. Non-nuclear orbital weapons are allowed, but to date nobody has fielded one.

An orbital weapon is highly restricted on ground targets it could reach. We don't know the HTV's cross-range capability (how far left/right of the trajectory it can steer in the atmosphere), but it's probably somewhat limited. Even the shuttle with its large wings only had a cross range of about 1,200 miles.

Due to orbital mechanics and limited cross-range, it would take a huge constellation of orbiting HTVs to strike any given point within 1 hr. However by using a sub-orbital launch on the required trajectory, it only takes one vehicle.

The HTV-2 was part of the Prompt Global Strike program. This could be done with conventionally-armed, precision-guided ICBMs. However they appear to trackers indistinguishable from a nuclear ICBM launch.

So one goal is produce a conventionally-armed weapon with the reach and responsiveness of an ICBM, yet which doesn't fly an ICBM trajectory. HTV is one example. That would avoid it being detected and classified as a possible nuclear-armed ICBM launch. http://en.wikipedia.org/wiki/Prompt_global_strike

[Solfe]

Didn't Tom Clancy write about using tomahawks missiles with a mission profile like this? Red Storm Rising, maybe. The mission called for spending a couple of days getting subs into range of a Soviet airfield, then the subs hanging out until a couple of squadrons Soviet bombers were on approach. Then the subs launched the tomahawks at the airfield to destroy the runways. The bombers had already passed the abort point so they had to land or have the crews bail out. Mr. Clancy likes the perfect timing, all weapons work as advertised missions.

As I recall the Soviets had a really negative reaction to something that could have nuclear warhead sailing over their country; what the attack did was a secondary issue to them.

Even if you can range side to side a fair bit, you would have to fly over stuff you don't want to hit. Fast, yes. Could something like this actually be battlefield functional? I can't imagine that the thing would have a warhead(s) big enough to do a lot of damage, so how many would you need to launch?

Just thinking this through a little bit, isn't it considered difficult to impossible to land spacecraft next to each other on the moon or Mars? Perhaps when this program dies, they will have enough data to make that task easier.

[Garrison]

As I recall the Soviets had a really negative reaction to something that could have nuclear warhead sailing over their country; what the attack did was a secondary issue to them.

Even if you can range side to side a fair bit, you would have to fly over stuff you don't want to hit. Fast, yes. Could something like this actually be battlefield functional? I can't imagine that the thing would have a warhead(s) big enough to do a lot of damage, so how many would you need to launch?

Well it's going to pack a lit of kinetic energy when it hits so maybe you wouldn't need a warhead?

[Solfe]

You are right. I shouldn't have used the word "warhead(s)". I was sort of picturing the HTV2 as a bus to carry several smaller "impacting smart weapons". I don't know what to call those.

[ravens_cry]

Just thinking this through a little bit, isn't it considered difficult to impossible to land spacecraft next to each other on the moon or Mars? Perhaps when this program dies, they will have enough data to make that task easier.

Difficult, sure. But impossible?

[Solfe]

I had forgotten we did that.

"This was the first — and, to date, only — occasion in which humans have "caught up" to a probe sent to land on another world."

Is this the only time we got two space craft together on the ground? I do recall Phoenix being photographed as it came into the Martian atmosphere. That's got to be just as hard.

[ravens_cry]

I really don't know.
Personally, I can see a logic in putting probes far apart.
If you are going to send two, like on Opportunity and Spirit, as well as Viking I and II, you probably want them in fairly different conditions to maximise original data collected. That said, Opportunity is getting pretty close to Spirits last stomping grounds, but that is a rover roving rather than a precision landing.
All in all though, Apollo 12 and Surveyor III shows that the capability exists, if not the necessity.

[cjameshuff]

The HTV-2 was part of the Prompt Global Strike program. This could be done with conventionally-armed, precision-guided ICBMs. However they appear to trackers indistinguishable from a nuclear ICBM launch.

So one goal is produce a conventionally-armed weapon with the reach and responsiveness of an ICBM, yet which doesn't fly an ICBM trajectory. HTV is one example. That would avoid it being detected and classified as a possible nuclear-armed ICBM launch. http://en.wikipedia.org/wiki/Prompt_global_strike

So instead of being detected as a possible nuclear-armed ICBM, it will be detected as a possible nuclear-armed hypersonic bomber. I don't really see the advantage here.

Just thinking this through a little bit, isn't it considered difficult to impossible to land spacecraft next to each other on the moon or Mars? Perhaps when this program dies, they will have enough data to make that task easier.

How's it going to do that? How could a hypersonic bomber hitting targets while gliding in Earth's atmosphere be at all relevant to doing this?

[Solfe]

How's it going to do that? How could a hypersonic bomber hitting targets while gliding in Earth's atmosphere be at all relevant to doing this?

I think it would be relevant due to the study of hypersonic aerodynamics and remote or autonomous systems. In ravens_cry's example of the Apollo mission, the autonomous/remote systems would be more important. In a different case such as Mars landers, the aerodynamics are just as important (edited here). However, I would like to point out that ravens_cry already questioned the utility of such missions unless you are sending multiple interdependent landers. (Perhaps I have highjacked this thread more than a little.)

[novaderrik]

Why am I not unhappy? Hm... let me guess, because it's military spacecraft...

you must be pretty unhappy if you don't like taking advantage of any advance that came about because it had a military purpose..

[Extravoice]

So instead of being detected as a possible nuclear-armed ICBM, it will be detected as a possible nuclear-armed hypersonic bomber. I don't really see the advantage here.

I was thinking the same thing. Maybe we're missing some critical feature of this technology.

If the military is interested in attacking distant targets quickly, this weapon doesn't seem to be any faster or more accurate than an ICBM. Certainly, it could (eventually) be fitted with nuclear warhead. The Hypersonic glider is interesting from a technological and engineering standpoint, but I don't see what problem it solves for military planners. I can even imagine the possibility of it creating problems.

If it has any substantial manuvering capability, it might even be more likely than an ICBM to trigger a knee-jerk retaliatory strike. I'm pretty sure that the world's major powers can determine if a missile launch is a threat fairly early in its trajectory. Imagine a hypothetical scenario where the US launches an ICBM at a North Korean site. The Chinese determine it isn't heading for them, and prepare a stern diplomatic response.

Now, imagine if a hypersonic glider weapon is launched, which is headed for North Korea, but looks like it could be hit Bejing. You might have have some nervous people with their hands on the retaliate button.

Maybe this isn't an issue, but I hope it is something that military planners think about.

[cjameshuff]

I think it would be relevant due to the study of hypersonic aerodynamics and remote or autonomous systems. In ravens_cry's example of the Apollo mission, the autonomous/remote systems would be more important. In a different case such as Mars landers, the aerodynamics are just as important (edited here). However, I would like to point out that ravens_cry already questioned the utility of such missions unless you are sending multiple interdependent landers. (Perhaps I have highjacked this thread more than a little.)

The aerodynamics are quite irrelevant on the moon, for rather obvious reasons, and the aerodynamics of hypersonic flight in Earth's atmosphere mean very little when it comes to precise landing on Mars. It's the variability and imprecise knowledge of the atmosphere of Mars that makes accurate landings there difficult, more data on Earth's atmosphere won't help much. In either case, the terminal phase which leads up to landing will be completely different from anything developed as part of the hypersonic bomber...the systems developed for guiding bombs to their targets and achieving a high-speed unpowered landing on a runway will not be particularly useful for landing on Mars, where there's no runways and barely any atmosphere even at ground level.

Rendezvous could certainly be useful (imagine resupply/upgrades for a rover with interchangeable laboratory modules and replaceable wheel-motor units/batteries), I just don't see any way this thing could be relevant to the task.

[jlhredshift]

To me, this is one of those things that proves that we do not have access to alien technology.

[ravens_cry]

To me, this is one of those things that proves that we do not have access to alien technology.

Well . . .
Imagine if we gave a broken SR-71 to the Wright Brothers. It wouldn't do them much good and that's a bit over three score years of difference. I am not saying we do mind, just that frangling things out, even with assistance from the stars, would take time.

[NEOWatcher]

Well . . .
Imagine if we gave a broken SR-71 to the Wright Brothers. It wouldn't do them much good and that's a bit over three score years of difference. I am not saying we do mind, just that frangling things out, even with assistance from the stars, would take time.

But we've been studying the Roswell craft since 1947... that's over three score years too.

[ravens_cry]

But we've been studying the Roswell craft since 1947... that's over three score years too.

My point was that aliens with the capability to visit us, either through known means or some aspect of physics we have not discovered, are probably hundreds, if not thousands, and potentially millions, more technologically capable. Think of the difference between the Wright flyer and the Blackbird, and all that in 63 years. Imagine the difference between something magnitudes more of a difference as well as an almost completely alien approach to problems.
Furthermore, heck, even if one believes in alien visitation, whose to say Roswell wasn't what was what they said it was and the actual incident was something completely different that happened significantly sooner.
Perhaps I should have put a "just" before the "a bit".