Iso-contour radar

[bigbeerbelly]

Is "ISO-CONTOUR RADAR" the same thing as weather radar?

BBB

[bigbeerbelly]

Found it!
move along, move along... nothing to see here...

Iso-contour radar is a type of primary radar used for weather detection. Pulses of radio waves are transmitted ahead of the aircraft in a sweeping motion and returns are received from reflection of the radio waves off precipitation. Range is a function of elapsed time between TX and RX, The steeper the contour gradient [on the display] the greater the presence of precipitation including rain, wet hail and possible associated turbulence and micro burst activity. [Hooks, scallops, fingers Etc.]

[Wodrick]

Wandering back decades, literally, 'Contour' was a term coined by the ECKO company, a British pioneer of Airborne Radar. It was a mode that was Pilot selectable that, when selected, inverted the video signal of the return above a certain strength, giving the Pilot an indication of the strongest return, similar to the red or magenta colouring on more modern colour radars. I don't know when it started being used, but the Comet and the 1-11 both had ECKO monochrome radars with contour.

[Dan Winterland]

And the RAF VC10s and C130ks still have it! One problem with the iso-echo function is that if it is left on and you fly into a very active cell, all you will see is a thin green line with a big black space behind it leading you to believe that all is well if you've forgotten you're in iso-echo mode. An Israli Airforce Herc broke up over Belgium many years ago. The iso-echo switch was found on in the wreckage leading the investigators to believe this is what happened.

I adopted the policy of never taking my hand off the switch if using it.

[Old Smokey]

I adopted the policy of never taking my hand off the switch if using it.
And the modern day Colour Radar equivalent - Use Manual Gain to 'tune out' the weaker returns when the screen is flooded with colour, but keep your hand on the knob and don't forget to return the Gain to normal after said examination.

Regards,

Old Smokey

[Dan Winterland]

Agreed, esp on the airbus where min gain is the selction adjescant to auto. Failed to notice the gain was at min when doing my line training, from the right hand seat it looked like it was in auto. The error was noticed after flying through a particularly bumpy cloud which wasn't showing on the radar!!!!!