Wake Vortex

[MrNosy]

Has anyone flown the High Approach Landing System/Displaced Threshold Operations (HALS/DTOP) on Runways 25R/25L('26L')at Frankfurt?
Any observations?

[Moonbeam Purple]

Works Ok! Nothing special - just a long taxi back to the V100's

Rgrds

MP

[MrNosy]

Thanks

[Christopher James]

Afternoon

ATCO here, just wondering about this system and what it's purpose is.

Is the idea that you fly above the vortex thereby permitting tighter spacing behind heavies? My initial thought is that I wouldn't be too happy about that; if he goes around the following traffic would still fly through the vortex.

Perhaps I have got the wrong end of the stick. :)

[CAT MAN]

THATS IT EXACTLY 09L...

[Christopher James]

I'm surprised. I believe the latest research shows wake vortex can climb as well as descend so even if the procedures require both aircraft to go around if the lower one does, I am not convinced that this is wise. I am not a mathematician but I would have thought that on a 3 degree glide path one would have to displace the threshold by 1 mile to be 100 feet above the preceding's profile? That doesn't seem a sufficient margin to me.

How much is the threshold displaced by? Is there a second glide path or is it purely a visual thing?

It is an interesting idea. I know they thought about it here for a while; I don't know why it was shelved.
:)

[ 05 August 2001: Message edited by: ZeroNine Left ]

[Warped Factor]

I may be wrong here, but aren't the two approaches to separate but closely parallel runways?

That is, normal approach on one runway and the steeper approach on the parallel runway beside it?

The runways not being deemed far enough apart to be totally independant hence this technique being developed?

WF.