Thread: x-47b

Originally Posted by Skywatcher

I was thinking of the value it gives to early warning. If you have enough warning and a sense of direction, you could use various EW/CIWS measures to at least target the munitions coming out of the B-2 (though the efficacy of such a tactic would depend on the target in question).

Not to mention whatever radars the engineers come up with throughout the world in the next decade.

I think it's way off, but my guess something bi-static with a combination of passive radar with a combination of active transmitter but then again you would need to track it. There were classified programs in the US "Silent Sentry" that utilized PCL.

Silent Sentry is a PCL technology developed by Lockheed Martin for all-weather surveillance and tracking of aircraft and missiles. Unlike conventional radar, PCL does not mechanically scan a volume of space or actively radiate a radio frequency signal. Instead, it passively listens for reflections of electromagnetic signals already in the environment from sources such as commercial television and FM radio.


PCL is capable of tracking multiple objects above a threshold detection size with accuracies purportedly comparable to C-band radar. Although PCL requires high-speed parallel processing to extract the targets from the received signals, its advantages are reduced operational and maintenance costs because of its mechanical simplicity and no interference with payload electronics or environmental impact because of its passive approach.


An onsite demonstration during the launch of STS-103 in December 1999 was the first phase of a NASA plan to assess the application and feasibility of implementing PCL technology as a primary or supplementary tracking and surveillance source for future and existing space launch vehicles.


A followup phase consisted of software and modeling modifications based on lessons learned from the onsite testing.

Passive Coherent Locator

Originally Posted by zraver

If the B-2's only emissions besides air turbulence is directionally shielded satellite communications and LPI AESA radar.... what is there to detect?

I was thinking of hyperspectral imaging (yes, I know 'radars' was a bad choice of words on my part). Granted, what I do know about hyperspectral imaging comes from a few popular magazines, so it's just wild mass guessing on my part. (Stuart Slade mentioned something about stealth detection, I will have to dig that up, if I ever get the time to).