6 ms·

ICBM's fly outside of the atmosphere and they don't turn... IE. they're ballistic. I could see that something designed to hit the predictable path of a ballist

by cleaver 15y ago

ICBM's fly outside of the atmosphere and they don't turn... IE. they're ballistic. I could see that something designed to hit the predictable path of a ballistic missile at mach 20 would fail to hit an aircraft which can turn at mach 20. (How well this thing can actually turn is another question.)

Groxx 15y ago
Granted, the 'ballistic' part does decide it. But what says ICBM tech can't be adapted to simply turn slightly while re-entering? It's not like this plane will be making hair-pin turns, I find it extremely hard to believe something with no need to fly back can't match it for maneuverability.
- hugh3 15y ago
  But what says ICBM tech can't be adapted to simply turn slightly while re-entering? Mostly the letter "B" for "ballistic". You can turn while flying. You can't turn while falling. You can stick out a little control vane to try to change course a little bit, but at that sort of speed, in that sort of atmospheric density, and bearing in mind that during re-entry anything that is at all pointy will get burned off, I doubt you could do much at all.
  - Groxx 15y ago
    Hence adapted, and referring to the tech, not the object. Making a ballistic missile not-ballistic makes it into something else. That this was a "plane" is inconsequential, and not even interesting, in terms of missiles - that they had at least minimal control at that speed is either a breakthrough, or duplication of existing techniques that can be applied to big-ass missiles (there, swap the B with "Big") more easily and more cheaply than to something designed to be re-used. Which, given the difficulty in adding controllable movement at such speeds to something way more complex than a one-use missile, implies to me that the techniques have existed for a while in cheaper forms, and this is just the first time they've been able to do it and (nearly) recover the device. That's significant, but it's not a game-changer for missiles or making things go boom.
  - arethuza 15y ago
    Maneuverable RVs have been flight tested - notably the US AMaRV.
  - burgerbrain 15y ago
    Of course you can turn while falling. Hell, you can turn without air. It's a rocket.
    - hugh3 15y ago
      Of course you can turn while falling. Hell, you can turn without air. It's a rocket Ah, but then you're no longer falling. You're not even "falling with style".
jasonwatkinspdx 15y ago
This is incorrect. Modern ICMB designs include maneuverable reentry vehicles. Even modest accuracy in an ICBM requires at least a minimal amount of course correction in the terminal phase. But apparently state of the art re-entry vehicles are capable of much more complex maneuvers including 180 degree turns (heading on ground, not the full 3d vector obviously). The US has had this capability since a research project in the 1980s. Some form of it is deployed on Trident as well as the comparable UK and CH systems. There is very little published on the topic, but if you start researching the AMaRV project you'll find some details and claims. Of course there's really no way for someone outside the defense community to confirm these claims, but I know of no physical reason why they couldn't be true.
niels_olson 15y ago
see my comment below: radius of an 8g turn at mach 20 (330 m/s * 20) is 555 km. I choose 8 g because that's roughly what we think a sunburn (ss-n-22) can do, and that thing is built like brick shit-house. now, to add to that: the radius of a 1 g turn at mach 20 is 4444 km. The radius of the earth is 6378 km. They've got to at least consider orbital mechanics just to hold altitude constant. Able to maneuver and highly maneuverable are two different things. The Titantic was able to maneuver. Just couldn't move fast enough. Now, let's think about some other fun stuff, everybody join in. Here's one: at mach 20, you need something along the lines of the shuttle's thermal protection system. We're talking plasma hot. Wrap this thing up in 3 inches of glass and I'll bet you've lost significant payload volume.
- adrianwaj 15y ago
  In terms of payload, and as someone asked below, "ordinance and yield" Would it actually need any? Smashing mach 20 into a target would yield tremendous kinetic force without explosives. Same principle as a http://en.wikipedia.org/wiki/Railgun http://en.wikipedia.org/wiki/Railgun where projectiles travel at 5,400 mph, and the gun can be situated on an aircraft carrier. On that note, the article above mentions railguns as way to launch spacecraft into orbit: applicable for this Mach 20 plane.

by cleaver 15y ago

Groxx 15y ago

Granted, the 'ballistic' part does decide it. But what says ICBM tech can't be adapted to simply turn slightly while re-entering? It's not like this plane will be making hair-pin turns, I find it extremely hard to believe something with no need to fly back can't match it for maneuverability.

hugh3 15y ago
But what says ICBM tech can't be adapted to simply turn slightly while re-entering? Mostly the letter "B" for "ballistic". You can turn while flying. You can't turn while falling. You can stick out a little control vane to try to change course a little bit, but at that sort of speed, in that sort of atmospheric density, and bearing in mind that during re-entry anything that is at all pointy will get burned off, I doubt you could do much at all.
- Groxx 15y ago
  Hence adapted, and referring to the tech, not the object. Making a ballistic missile not-ballistic makes it into something else. That this was a "plane" is inconsequential, and not even interesting, in terms of missiles - that they had at least minimal control at that speed is either a breakthrough, or duplication of existing techniques that can be applied to big-ass missiles (there, swap the B with "Big") more easily and more cheaply than to something designed to be re-used. Which, given the difficulty in adding controllable movement at such speeds to something way more complex than a one-use missile, implies to me that the techniques have existed for a while in cheaper forms, and this is just the first time they've been able to do it and (nearly) recover the device. That's significant, but it's not a game-changer for missiles or making things go boom.
- arethuza 15y ago
  Maneuverable RVs have been flight tested - notably the US AMaRV.
- burgerbrain 15y ago
  Of course you can turn while falling. Hell, you can turn without air. It's a rocket.
  - hugh3 15y ago
    Of course you can turn while falling. Hell, you can turn without air. It's a rocket Ah, but then you're no longer falling. You're not even "falling with style".

jasonwatkinspdx 15y ago

This is incorrect. Modern ICMB designs include maneuverable reentry vehicles. Even modest accuracy in an ICBM requires at least a minimal amount of course correction in the terminal phase. But apparently state of the art re-entry vehicles are capable of much more complex maneuvers including 180 degree turns (heading on ground, not the full 3d vector obviously). The US has had this capability since a research project in the 1980s. Some form of it is deployed on Trident as well as the comparable UK and CH systems. There is very little published on the topic, but if you start researching the AMaRV project you'll find some details and claims. Of course there's really no way for someone outside the defense community to confirm these claims, but I know of no physical reason why they couldn't be true.

niels_olson 15y ago

see my comment below: radius of an 8g turn at mach 20 (330 m/s * 20) is 555 km. I choose 8 g because that's roughly what we think a sunburn (ss-n-22) can do, and that thing is built like brick shit-house. now, to add to that: the radius of a 1 g turn at mach 20 is 4444 km. The radius of the earth is 6378 km. They've got to at least consider orbital mechanics just to hold altitude constant. Able to maneuver and highly maneuverable are two different things. The Titantic was able to maneuver. Just couldn't move fast enough. Now, let's think about some other fun stuff, everybody join in. Here's one: at mach 20, you need something along the lines of the shuttle's thermal protection system. We're talking plasma hot. Wrap this thing up in 3 inches of glass and I'll bet you've lost significant payload volume.

adrianwaj 15y ago
In terms of payload, and as someone asked below, "ordinance and yield" Would it actually need any? Smashing mach 20 into a target would yield tremendous kinetic force without explosives. Same principle as a http://en.wikipedia.org/wiki/Railgun http://en.wikipedia.org/wiki/Railgun where projectiles travel at 5,400 mph, and the gun can be situated on an aircraft carrier. On that note, the article above mentions railguns as way to launch spacecraft into orbit: applicable for this Mach 20 plane.