Wake turbulance
Thread Starter
Joined: Oct 2004
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From: UK
Wake turbulance
whilst flying in the Southend area in an R22 I was cautioned by ATC of the operation of a sea king manouvering at the end of the pier and advised that the separation is 4 nautical miles.
Can anyone advise me of any restrictions I may have if I am above and in sight of the sea king
Can anyone advise me of any restrictions I may have if I am above and in sight of the sea king
Better red than ...

Joined: Aug 2004
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From: Appleby-in-Westmorland Cumbria England
Was that a radar or non radar wake vortices separation situation?
(and don't they form downwind/ behind the subject aircraft?)
Helicopters produce more wake vortices than aeroplanes of similiar weight. On radar separation a light (R22) after a medium (Sea King) would be 5nm. 4 would be a heavy after a heavy.
Was there a TRA for similiar in place around a situation?
Questions, more questions but never answers ...
h-r
(and don't they form downwind/ behind the subject aircraft?)
Helicopters produce more wake vortices than aeroplanes of similiar weight. On radar separation a light (R22) after a medium (Sea King) would be 5nm. 4 would be a heavy after a heavy.
Was there a TRA for similiar in place around a situation?
Questions, more questions but never answers ...
h-r
Thread Starter
Joined: Oct 2004
Posts: 11
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From: UK
Hi Helicopter Red-Eye,
It was non radar
My intentions at the time was to route past the sea king no closer than 1 nm above the height of the sea king. (the sea king was working below 100 feet)
I just felt that the separation in this situation seems excessive.
Any advise would be appreciated
My last post should read no closer than 1nm and above the height of the sea king. Also there was no TRA.
It was non radar
My intentions at the time was to route past the sea king no closer than 1 nm above the height of the sea king. (the sea king was working below 100 feet)
I just felt that the separation in this situation seems excessive.
Any advise would be appreciated
My last post should read no closer than 1nm and above the height of the sea king. Also there was no TRA.
Avoid imitations



Joined: Nov 2000
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From: Wandering the FIR and cyberspace often at highly unsociable times
The ATC requirement for a 4 mile separation is for aircraft following the same flight path, such as on a route or on the approach to a runway.
It's only advisory; if you remain above the preceeding aircraft and preferably upwind you will be clear of the wake as it goes downwards and downwind. However, if you aren't sure then obviously you should play safe.
It's only advisory; if you remain above the preceeding aircraft and preferably upwind you will be clear of the wake as it goes downwards and downwind. However, if you aren't sure then obviously you should play safe.
Thread Starter
Joined: Oct 2004
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From: UK
Hi Shy torque, thanks for making it clear for me. I thought ATC wanted me to fly no closer than 4nm from the aircraft.
After returning from california where I was flying at a busy airfield we often flew quite close and above very large C17's. Now I understand ATC's Caution, thanks.
After returning from california where I was flying at a busy airfield we often flew quite close and above very large C17's. Now I understand ATC's Caution, thanks.

Joined: Oct 2005
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From: Australia
Just for the hell of it I'll weigh in.
(From an australian perspective) If its day/vmc you, as the, presumably, light wake turbulence category aircraft who wants to pass clear of the medium category aircraft can elect to waive the wake turbulence separation...this way you take on all the responsibility for staying clear of his wake turbulence (ie remaining above and upwind)
(From an australian perspective) If its day/vmc you, as the, presumably, light wake turbulence category aircraft who wants to pass clear of the medium category aircraft can elect to waive the wake turbulence separation...this way you take on all the responsibility for staying clear of his wake turbulence (ie remaining above and upwind)
Joined: Jun 2005
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From: midlands
Are you certain it was for wake turbulence or was it because a temporary danger area had been established and you were about to penetrate it?
Often SAR ac ask for TDA's to protect them from other traffic - especially the very fast pointy stuff at low level. However, do you, as a civilian ac have to comply??
Often SAR ac ask for TDA's to protect them from other traffic - especially the very fast pointy stuff at low level. However, do you, as a civilian ac have to comply??




