Zapped by Radar
 

Crossing the pond with a bloke 1 mile in front and 1000 ft below. Must have been fried by my radar by the time we crossed. Hope he was shielded by that aluminium tube. Any comments bout this from techkies?

Not a problem !
 

At that range the "microwave" effect of your radar is not a problem to do any damage a person would have to be within about 50 feet ( if my memory serves me correctly ).

However I am told that the BA ground engineers at LHR "killed" a police radar speed gun that was being used on the ramp by giving it one or two sweeps of the WX radar from a 757.
I can only think that the gun was looking for an RF return of about 0.075W and got 200W from the 757 !.

http://hps.org/publicinformation/ate/q315.html

In short its not a problem beyond 10 feet.

Had a B737 in dock on a C check once. Avionics guys were working on the radar. It was on. Unfortunately a lead was working on the dock in front of the aircraft. The radome blocked their view. She was exposed to it for around an hour.

She spent quite a time in hospital and many months off work afterwards and took a couple of years to fully recover.

Procedures were changed after that.

If we assume the radiated power is 50,000 watts, I make the power the guy would get standing there as 1/30 millionth of what he could get from a microwave oven operating at the maximum allowed end of life leakage.

However, how much more cosmic radiation he got from flying at 30,000 or so feet than being on the ground is another matter......especially as the aluminium tube doesn't do much to stop that!

Hi all,

Then I'm wondering why our Ops manual for the B737-700 tells me the safe distance for the WX radar, in the full 180 degree forward arc, is 275 feet!

Cheers

Probably because your aircraft is US built, they tend to err on the side of safety to avoid any lawsuits. Note the number of decals around the aircraft stating the obvious.
My particular favorite is the one on the inside of the DV window frame on a 757 which says "Window open"! :)

Can't comment on the damage done by the radar other than we never stand in front of them when it's on and NEVER use it inside the hangar. Same goes for HF transmissions.

Flight Detent says:

>Then I'm wondering why our Ops manual for the B737-700 tells me the safe distance for the WX radar, >in the full 180 degree forward arc, is 275 feet!

I'm not sure what the effective radiated power is for a weather radar - I assumed 50,000 watts. On that basis, if we assume the standard saftey level of 1mW/sq.cm (10 watts/sq. metre), then at 275 feet, the power is 0.566 watts/sq. metre.

That takes no account of the fact that you have to take average, not peak power into account (that drops the effective power by the duty cycle) and for radhaz work, you also integrate the total exposure over 6 minutes.

It's still not a good idea to get too close though. When I did the radhaz course, there was an exercise to find leaks in the waveguide of a 2 MW radar transmitter (the radiated power was much higher): I found them faster by running a hand along the waveguide and feeling for the warm place than was managed with the proper intrumentation. Not really recommended!

The eyes are the first things to go, by the way......

Heard of a bloke who managed to burn a hole in his hand doing that regularly, over a prolonged period. Doesn't do the tissue much good in the long run.

Well mate it depends what your flying, RADAR technology has come on leaps and bounds,if your flying a glass cockpit ship you could be sat in front of the radome for 5 mins without any harm,if its a unmodified older generation ship then i wouldnt like that 5 minutes unless your one of these guys that hates kids anyway!

Old Radar
 

Many moons ago read a story (maybe Urban Myth) about a US pilot having severe headaches, followed by sight loss. Subsequently he recalled having been standing chatting for a significant period, leaning on the radome of of his A/C (I heard DC9 but must have been a low set nose!), and then boarding to find the radar ahd been left on. When his problems developed, he was told due to the Frq/Wavlelntgh of the radar (approx 3 Cm), there were four organs in the body of a size susceptible to microwave-style heating and tissue damage (dipole effect or somesuch) , two of which were his eyeballs!

Good to stay away from.:sad:

HM Police enforced speed control in the ramp
 

Ha ha ha that can only happen to a UK Cop (Bobby)....
law enforcement on the ramp. I hope he is prepared to
take all the radiation and emission on the ramp during his
duty. Poor bloke, he better seeks a transfer to the greens...

NG

You would think that someone would incorporate a safety circuit into the radar system that dumps the radar tx signal when the aircraft is on the squat switches.. is it too late to patent this idea ?

oh yes.. it is now :(

Simjock,

Would be a good idea however we need the wx radar on to look at the departure path before take off to check for CB's etc.

The 737NG and I assume others have a predictive windshear system which utilises the wx radar on the ground during the initial part of the take off roll to check for windshear.

Already been done SimJock I'm afraid. Some business jets (the Cessna 560 to name one) already have TX inhibited on the ground.

No large bag of cash for this idea, looks like you will have to continue in your current employment for a little longer!! :O


Regards


The Doc

Ahhh.. OK then, I'll settle for a system that switches off with the engines then.. that suit ?

Yes I think it would. I hope you will remember the little pepole when your rich. :O

All the best

The Doc

WX radar off on engine shutdown????

Poor marshaller..... might make his bat's glow at night if his batteries fail though....????!!! Maybe something else too......!

Le-Slat

ehm... couple it with the squats AND the flaps perhaps?

GND+flaps 0 -> radar off
GND+flaps whatever -> radar useable
FLT+ flaps 0 -> radar useable

No takeoff without flaps and after landing you anyway select them up!

SHOW ME THE MONEY!:} :}

(maybe it can buy me a course in learning to write proper English, so I don't have to edit for typo's the whole time:hmm: )

Should we be worried???
 

Hi guys,

I'm a purser with Domestic carrier. Quite often I will enter the flight deck before departure and chat to the tech-crew during boarding.

On more than a few occasions I have noticed the WX radar sweeping along merrilly and displaying a nice solid bank of buildings in front of us. Is this the sort of stuff infertility and eyesight-loss is made of?

Just asking, because when I'm downstairs dropping off my o/night bag, I want to know if I should just leave it that little bit further away...

Cheers :ok: