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Effect of a helicopter behind you?

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Effect of a helicopter behind you?

Old 8th Oct 2018, 15:50
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The quote was... A helicopter produces downwash equal to its weight.
Yes but an airplane does the same. The only difference is that the helicopter may be several time heavier than the airplane. However the downwash will be in all radial directions from the helicopter.
We have mingled with rotary traffic before, but my worst 'upset' was when trying to taxi to the pumps, when a chopper did the same thing.
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Old 8th Oct 2018, 15:58
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However the downwash will be in all radial directions from the helicopter
In the hover, yes. In forward flight, the downwash will be very similar to that of an airplane, complete with vortexes.
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Old 8th Oct 2018, 16:01
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The lack of understanding about fundamental POF displayed by some here is a little scary!

Please, take a moment to analyse things.

Actually, the entire thread is ridiculous! (Sorry, but it is)
..……..
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Old 8th Oct 2018, 16:56
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The Odd One - did your incident occur just west of London?? If it is where I think it is, I had a conflict with a helicopter there too ( circuit, not downdraft) and was flying with the sister of the lady in the tower, who was very diligent in filing a report form !
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Old 8th Oct 2018, 22:08
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Surely a helo in forward flight produces virtually no downwash? Wake turbulence certainly, but whether that is much if any more than a comparable weight f/w I don't know. Downwash in the hover is a totally different thing and in no way comparable to what happens in forward flight.The aerodynamics of hovering and forward flight are totally different.
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Old 8th Oct 2018, 22:38
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Originally Posted by ShyTorque
I'd be interested to see a mathematical explanation of that phenomenon.
The mathematical explanation would be that it's a Harrier.
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Old 9th Oct 2018, 00:02
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I saw two Harriers take off in front of a crowd of spectators at RAF Sealand. They both blew 4 foot wide holes in the grass, with the divots going all ways.
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Old 9th Oct 2018, 18:49
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Originally Posted by gerardflyagain
Hello! After trying 2 get a PPL (A) 2 years ago and getting interrupted by life I'm back in the cockpit and determined to get it this time... I have a question: What effect can/does a helicopter behind you when in a circuit have?

This site talks about the effect of a hovering chopper, and a chopper that is ahead of you and moving forward. But I can't find anything on a chopper coming in behind you. Thanks.
It depends. Shall we assume the chopper started shooting at you already? If you dropped a bomb before it may be reasonable.
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Old 10th Oct 2018, 09:24
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Old 10th Oct 2018, 12:23
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Hovering helicopters - avoid taxying past. Indeed I refused a taxy clearance recently as it would have taken me <100m from a hovering Puma. To be fair ATC took the point and asked him if he’d mind moving, which he did very shortly afterwards
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Old 10th Oct 2018, 12:29
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Same here, only in my case it was a SAR helicopter preparing for a winch demonstration. They were already at winch height (what's that? Maybe 30 meters?) but not yet in position. Stopped, informed ATC and ATC kindly asked the heli to move a bit. Non-issue.
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Old 10th Oct 2018, 13:20
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I was sitting in the back of a PA-28 while the pilot did the walk round, the door was partly open. A JetRanger hover taxied past at about 50', buffeting the aircraft and banging the door wide open. We then started and taxied to the pumps with the door closed - couldn't open it from inside. Fuel man opened it from outside; an engineer replaced a broken split pin somewhere in the latching mechanism, all dandy again. Glad the previous occupant hadn't topped it up after their bimble...
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Old 18th Oct 2018, 08:57
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Thanks all. RIP to those mentioned who have died.
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Old 18th Oct 2018, 10:43
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Originally Posted by rudestuff
You're unlikely to find a helicopter behind you in a circuit: they are supposed to avoid the flow of fixed wing traffic.
"Supposed.."?
Are they?

Maybe local guidelines suggest this but normally anyone can fly in the circuit.
The point is most times a helo does't want or need to conform with a f/w circuit and may well hinder aircraft behind as it comes to a hover on arrival so agreed it is usually best to avoid the f/w circuit but "supposed to avoid" is a bit strong, I think.
There are occasions when you need to/it is better to conform to a f/w traffic.
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Old 18th Oct 2018, 13:16
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@sam rutherford.

Sam, I’m more surprised that you’re surprised!

From an operational point of view dealing with any circuit traffic regardless of fixed or rotary or wherever it is in the circuit is something I’d expect a low hour PPL student to be asking.

There was a sign in an old crew-room which stated “The only stupid question is the one you don’t ask.” - As seasoned instructors we should be encouraging questions like this, then perhaps the level of knowledge would be far higher.

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Old 19th Oct 2018, 15:37
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The question was about a helicopter behind a plane.

The answer was 'none'.

If the other answers (to other questions) are to be kept, then perhaps the thread title should be changed to become a more general query about helis and planes in proximity?
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Old 19th Oct 2018, 17:56
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This reminds me of a scenario a few decades ago.

Arriving at Andrewsfield flying a helicopter the guy on the radio replied G-XXX understand downwind cleared to land.

So landed downwind and hopped across the runway.

He was a bit annoyed thinking it was a fixed wing.
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