My reply to swingkids questions:

1. Plasma deposition is a manufacturing process, that is both expensive and complex if done properly. I have seen film of this process taking place inside a vacuum chamber…..literally by creating a plasma and then ‘depositing’ the plasma onto the target material, allowing the plasma to cool into a material which builds on the target surface. The vacuum is essential in order to stop impurities affecting the produced material (these impurities are caused by the plasma literally breaking air down, allowing molecules to be combined in the plasma cloud).

2. The deposited material can be energised to cause a plasma type field to form. In general, electricity is used and the electricity must remain on to keep the plasma field active. It would appear that the plasma cloud is then lost (converted to a gas) when the power is switched off. In essence the manufacturing process must then account for this, depositing enough material to ensure a useful life. What mass of material is lost making the plasma cloud and how quickly this material might be lost are questions that soo far I do not have answers to. Although I believe that a fixed mass of material is used to create the plasma cloud and then no other material is inputted to the cloud during the time for which the plasma exists(unless some of the cloud is lost, whereby equilibrium must be maintained, and thus some more material ionised from the original surface).

3. The manufacturing process deposits a layer of material onto any surface panel/antenna/whatever. This is the material that is then used to create the plasma cloud. The cloud remains close to the surface it originates from. Although it makes sense to me that the more energy you pump into the cloud the bigger the cloud will be. Because a plasma cloud in our case is pretty much an ionised gas the layer of material the cloud originates from can be pretty thin, and also the depth of the plasma cloud can also be very thin. Practically, an electric field is produced that TOTALLY absorbs any EM energy that enters the cloud.

Why the interest in electrical capacity? It has been mused here and was also my belief BEFORE the conference (hell I didnt believe plasma stealth was practical at all…) that the power draw required to maintain such a field would be larger than could be supplied by the engine accessory drives, whilst powering the rest of the aircraft. RATS are right out. However it would appear that the current draw can be carried by current generation high performance engines. The power required for this application is obviously related to the area (possibly the volume) of plasma creating surface to be used, along with the depth of plasma field required, besides atmospheric requirements.

4. We ARE talking about screens and shields! you see the plasma material is applied as a surface treatment, and it is then used to create a plasma cloud or field of a certain volume. We are not concerned with filling volumes with plasma at production or in operation. That really would be expensive in terms of power and somthing of an overkill…..You can hide anything with this system. The most obvious reflectors in military aircraft are cockpit areas and antennae(not considering external payload!). If you shielded just these areas with this method you would arrive at a significant reduction in detection range (through a reduction of the ‘nominal’ radar cross section) Another good advantage of this system is that it can be turned on and off at will, so you may even be looking directly at it(for example at an airshow! ) and never know it was there until the radar lock alarms started sounding.

5. A near operational(i.e. scientific flight test) test was carried out using two of the same type of aircraft. One was treated with the system (no details of where the system was applied were given but I am expecting it to be antenna and canopy only) one wasnt. The detection range was HALVED with the system on. This is two aircraft in the air with another aircraft looking for them in a set scenario, this was not a ground test, a video of the aircrafts radar display was shown.

It was confirmed that the system has been applied to the exterior of the whole aircraft( I mean ALL OF IT), and tested both on ground and in air. However the group were having some operational problems with it. I would imagine that these problems would revolve around the effects of the moving air around/through the plasama cloud/field. As we probably all know the boundary layer is characterised as a region of velocity shear, from 0 at the surface to the free stream veolcity, over a short, calculable, distance. It would seem that the velocity of the aircraft (or air depending on your viewpoint) seems to be ‘washing’ the cloud away and it cannot be replaced quick enough or at all, since the whole system should be in equilibrium, but if the plasma cloud is swept away too quickly there is a fair chance that the system moves out of equilibrium and it shuts down……of course if your plasma is contained within a radome or between laminates of a canopy its going to stay in equilibrium, no matter how fast your travelling.

Applications of this sort of system is a little trickier to discuss. Safe to say it doesnt have to be put directly onto the antenna, neither does it have to be directly put onto the inside of the radome (a huge sigh of relief for manufacturers no doubt! ).

and why use complex plasma creating materials?

once you understand the whys and the wherefores, other existing and in use technologies are VERY easily converted into similarly useable systems.

Photo of Su27 on outdoor range and anechoic chamber……..

coanda

Hope this is interesting and helpful!