Weather radar returns

[Jesper]

Hi there. I have seen some strange weather radar responses a couple of times now over more or less the same position over germany. It looks like a very pointy V, formed by yellow and red returns, pointing towards me. Iwe asked a couple of friends and I have heard lots of different answers, the two that sounds most likely is either that their is moisture inside of the cover of the radar, or that it is produced when my aircraft pics up returns from a military aircraft with a very strong radar.

For your information, im sailing around in a b738ng if their is different kind of weather radars out there.. :P

[MD11forever]

Experienced that myself, always at the same position in Italy, so I doubt it has something to do with moisture inside the cover.
I was told this has something to do with military radar stations on the ground.
But maybe somebody knows for sure.

[Rainboe]

These fill the screen, from the bottom point fanning out all over the screen? Interference- from what I have no idea!

[TopBunk]

I believe it to be radar spiking by the military. Happens often near sensitive installations and in places of conflict, hence the requirement for civil aircraft to have their radars on and to monitor 121.5 in these areas.

[BOAC]

Other radars normally produce what is known as a 'spoke' (not 'spike') which originates at you and expands gently out towards the top of the screen on the azimuth of the TX. Not a 'normal' occurrence since powerful mil radar frequencies are far away from civil but sometimes a harmonic will pop up. Civil stuff is pretty low-powered and may produce one. You'll never know until the missile hits you........................, :). Radar jargon - 1 (http://www.radarpages.co.uk/glossary/glossary.htm)

[MD11forever]

Interesting discussion covering the same topic:
http://www.pprune.org/archive/index.php//t-344799.html

[FCS Explorer]

had that twice recently near MUC/EDDM/Munich coming across the alps from the south.

[eagerbeaver1]

I get it all the time - looks light a search light originating from us. I presumed it was another radar tracking my aircraft (deliberately). I have had it almost everywhere except the UK.

[Graybeard]

Sometimes it shows up as a narrow void, or reverse spoke. I have seen it from ships off San Diego, Calif, and Southern Nevada. To verify it's a ground source, turn the plane a few degrees.

Mil. a/c used to use airliners as practice targets - until TCAS came along and showed the games they were playing. Even after that, America West was seeing lots of pilot squawks for phanom targets over Southern Nevada. It was apparently from nifty ground radars that could make your TCAS look like you had four bogeys approaching from four directions. After a technical management meeting, an AMW pilot, who was USAF Reserve, got in touch and told them to knock that crap off. That pretty much ended the unverified removals of TCAS processors.

GB

[Jesper]

explorer, thats exactly where I experienced it as well...
I'we read somewhere else that it could be one of those big mil.ac with a radar disk on the roof that is locking its radar on you.

[K.Whyjelly]

Had this a few times myself over Germany and also routing from Charleston down towards Ormond Beach in Fla. Explanation I was given by an ex fast jet bloke was that we were being locked onto by AWACS.

[lamina]

My Collins manual states the following

ALIEN RADAR
The WXR-2100 radar incorporates a sophisticated alien radar rejection
algorithm that is designed to prevent interference from other airborne
weather radars. However, high power military radars and military
radar-jamming systems will “burn through” and cause display artifacts



This is followed by a picture showing a "spike" although I'm unable to reproduce it here!

[spacegrand]

ECM From a ground station or aircraft.