Further follow up.
I asked my brother, who was a member of the design team for the stealth
bomber, to have a look at the following from Inchoate:
> ...rf at that frequencies isn't a
> laser beam it's more like a
> reflective wave from a beach, the
> reflection loses the tight
> coherence from the incident wave
> (as a result of the radar guns
> waveguide). As a result the
> reflected wave splatters out into
> a rough semi-circle. This means
> you don't get those tight
> reflections that you're talking
> about.
>
> As to F-117's, the 'stealth effect'
> only occurs if the angle of
> indicence is very acute (ie much
> greater than 90 degrees), which is
> why the body panels are angled the
> way they are, the radar coming UP
> from the ground hits the side
> panels and gets reflected upward.
> If you had another aircraft at
> roughly the same altitude as the
> F-117 they would be able to take
> that reflected beam and use it to
> get a tight lock on the F-117 even
> though they didn't send out any
> beam. It even becomes possible in
> that scenario to shoot the F-117
> down without it knowing it ever got
> a 'paint'.
>
> THE primary means of detecting a
> stealth aircraft of the F-117
> variety is to have the transmitter
> in one place and receivers in others
> looking for those reflected beams.
Here is his analysis:
> Basic physics: Similar to a concentrated
> light beam shown on a mirror, RF energy
> reflects off of the surface of any body.
> If the viewing angle is near normal to the
> surface, the RF energy is reflected back
> to the source and a detection is relatively
> easy. If the viewing angle is off normal
> to the surface, the energy is reflected in
> a hopefully safe direction.
>
> Bistatic Radar Theory: The placement of
> the receiver will be dependent on the
> geometric relationship between the
> transmitter and the physical shape of the
> body being illuminated. Just being at
> near the same altitude is not enough.
> Even if (a big if because the reflections
> could be concentrated beams) a receiver
> can be placed in the reflected energy,
> making use of the information is highly
> complex. There is a whole bunch of RF
> energy floating around in the ether-space.
>
> Give him a C-
Methinks my brother is a very generous grader.
SURRENDER DOROTHY
S a n d y
