Simplified stealth: no power, non-reflective materials, almost no metal?

[cluttonfred]

Does anyone know of any projects using very simple stealth solutions like a light composite (or even wood, nature's composite) airframe, no engine and almost no metal?

For example, assuming that high explosive itself is not visible to radar, I could see such a solution being attractive for a long-range glide bomb as a cheaper and stealthier alternative to a cruise missile. A sailplane-like glide bomb with a 20:1 glide ratio could glide 75 miles from 20,000 feet. Even without exotic materials and techniquies, if the only metal were a few actuators, sensors, etc. there wouldn't be much for radar to see.

It would also work for one-way special forces delivery, but there there doesn't seem to be much interest in assault gliders these days.

Thoughts?

 

[lastdingo]

That's basically the effect that wooden airframe aircraft such as the Mosquito had in WW2.

 

[Racer]

And the bombshell and splinters would be out of... metal?

 

[cluttonfred]

And the bombshell and splinters would be out of... metal?

Not necessarily, it could be a blast-only warhead, just a whole lot of explosive to go boom. Or, there could be other, non-metal fragmentation, ceramic pellets, for example.

 

[Orionblamblam]

Or, there could be other, non-metal fragmentation, ceramic pellets, for example.

Depending on how nasty you want to be, the shrapnel could be made out of bone (cow, pig, whatever). Nice, rancid bone, left out in the sun for a few days, jam-packed full of biological nastiness.

Great for anti-personel, not so useful against hardened targets. And since the purpose is a stealthy weapon, implying some level of modernity WRT detection systems, then probably not very useful at all.

 

[quellish]

Does anyone know of any projects using very simple stealth solutions like a light composite (or even wood, nature's composite) airframe, no engine and almost no metal?

For example, assuming that high explosive itself is not visible to radar, I could see such a solution being attractive for a long-range glide bomb as a cheaper and stealthier alternative to a cruise missile. A sailplane-like glide bomb with a 20:1 glide ratio could glide 75 miles from 20,000 feet. Even without exotic materials and techniquies, if the only metal were a few actuators, sensors, etc. there wouldn't be much for radar to see.

It would also work for one-way special forces delivery, but there there doesn't seem to be much interest in assault gliders these days.

Thoughts?

Even small amounts of metal can still have a high RCS. The simplest solution is still shaping.

 

[AeroFranz]

I'm no expert by any stretch, but i suspect materials we claim to be RF "transparent" are all but. I haven't seen any study comparing the reflectivity of, say, a one square meter flat woof panel at ninety degrees to an incoming radar signal, versus aluminum, steel, carbon fiber, glass fiber, etc.
All i know is that in applications where you care for radar transparency, getting 98% is very good.

 

[DSE]

The German Horton? http://en.wikipedia.org/wiki/Horten_Ho_229

 

[PlanesPictures]

Maybe this one...

 

[Arjen]

Bio-power. Check. Non-reflective materials. Check. Zero metal. Check. Throw in bonus property. Check.

 

[Orionblamblam]

Bio-power. Check. Non-reflective materials. Check. Zero metal. Check. Throw in bonus property. Check.

It's been done.

 

[sferrin]

Bio-power. Check. Non-reflective materials. Check. Zero metal. Check. Throw in bonus property. Check.

Birds can be detected on radar.

 

[Apophenia]

Another possible non-metalic (and non-avian ) airframe material - concrete. Substitute carbon graphite for B+V's steel wires and make it one-piece to avoid the need for centre section connectors?

http://www.secretprojects.co.uk/forum/index.php?topic=6195.0

 

[quellish]

I'm no expert by any stretch, but i suspect materials we claim to be RF "transparent" are all but. I haven't seen any study comparing the reflectivity of, say, a one square meter flat woof panel at ninety degrees to an incoming radar signal, versus aluminum, steel, carbon fiber, glass fiber, etc.
All i know is that in applications where you care for radar transparency, getting 98% is very good.

I'm pretty sure I've seen a document on DTIC that goes through the results of that, specifically for X-band. I'll look around for it.
Everything has some level of resistance, so nothing is truly transparent. That's one of the reasons trying something like a Hopeless Diamond core of metal surrounded by a fiberglass lifting fairing wouldn't quite work. The old story is that Aquilla was largely transparent, and the metal inside contributed hugely to the RCS as a result.

It's interesting to note how the "pioneers of stealth" in the 70s changed things. Previously, aircraft were being turned stealthy. What they did was start out with a stealthy design and make it only as flyable as it had to be, and a large reason they were able to was the analytic and testing tools that were available to them.

The simplest VLO design is still probably going to be a faceted reflector like HAVE BLUE.

 

[Arjen]

Birds can be detected on radar.

Yes, with some difficulty, you can detect a single bird with radar. However, I was not being completely facetious. Imagine a flock of birds. One of them is carrying something nasty, and conditioned to seek out your bit of real estate. Which one? Being invisible is just one way of not standing out from your surroundings. Hiding in a crowd is another one. What constitutes stealth depends on the environment.

Scott's illustration possibly refers to this: http://en.wikipedia.org/wiki/Bat_bomb

 

[AeroFranz]

PETA would have LOVED this ;D

 

[quellish]

Birds can be detected on radar.

Yes, with some difficulty, you can detect a single bird with radar. However, I was not being completely facetious. Imagine a flock of birds. One of them is carrying something nasty, and conditioned to seek out your bit of real estate. Which one? Being invisible is just one way of not standing out from your surroundings. Hiding in a crowd is another one. What constitutes stealth depends on the environment.

Scott's illustration possibly refers to this: http://en.wikipedia.org/wiki/Bat_bomb

Suicide bombers are cheaper and easier to train.

 

[Arjen]

A suicide bomber's stealth relies on hiding in a crowd.

Suicide bombers are cheaper and easier to train.

What to choose? To name a few, it depends on
1) what your aims are, and
2) what you find morally acceptable

Once war breaks out, 2) often doesn't seem to be very important any more. Let's hope it doesn't.

 

[OM]

Suicide bombers are cheaper and easier to train.

...And can be manufactured using unskilled labor. Not sure if a contract is required, tho