Mountain Wave
Joined: Oct 2001
Posts: 3,832
Likes: 115
From: UK
Wave bars are usually only 3-4 nms apart. If you can't see the ground then try to imagine what feature is likely to be setting off the wave (assuming that you know your present position and the forecast wind).
Turn downwind for a couple of minutes and watch your ASI and VSI very closely. As soon as you start detecting an increase in speed and/or lift, resume your original track.
If it is not possible to fly parallel to the wave bar, then try flying a series of small doglegs. I have made considerable fuel savings making use of wave. I once saved 4000 lbs of fuel in an Argosy flying from Tehran to Cyprus and I have had a Belfast flying at cruise speed with the throttles at flight idle over the Massif in France.
I would have to say that my experience in wave soaring in gliders in such places as Dishforth, Sutton Bank and Aboyne comes in very handy. You don't have to have dramatic mountains to create wave and it can exist a long way downwind of the feature that is causing it.
I can remember someone getting to 17000 feet in Oxfordshire in weak wave created by the Welsh mountains.
Turn downwind for a couple of minutes and watch your ASI and VSI very closely. As soon as you start detecting an increase in speed and/or lift, resume your original track.
If it is not possible to fly parallel to the wave bar, then try flying a series of small doglegs. I have made considerable fuel savings making use of wave. I once saved 4000 lbs of fuel in an Argosy flying from Tehran to Cyprus and I have had a Belfast flying at cruise speed with the throttles at flight idle over the Massif in France.
I would have to say that my experience in wave soaring in gliders in such places as Dishforth, Sutton Bank and Aboyne comes in very handy. You don't have to have dramatic mountains to create wave and it can exist a long way downwind of the feature that is causing it.
I can remember someone getting to 17000 feet in Oxfordshire in weak wave created by the Welsh mountains.
Joined: Jan 2008
Aviation Qualifications: PPL
Posts: 187
Likes: 10
From: Third rock from the sun.
Gliding in wave
In order to begin to understand wave it might be very useful for a power pilot to experience it in a glider with an experienced mountain flying instructor. The best sites in the UK to give this sort of instruction are in Scotland so, Aboyne in Aberdeenshire, Portmoak in Fife and Feshiebridge near Aviemore. As others have said, you can get wave anywhere in the UK and some of the other gliding hill sites are good but none are as consistently as good as Aboyne.
It's a massive subject and even the experts like John Williams who flys from Portmoak will tell you that after years of exploring it, they are still learning - and he's a bloke who has flown offical 1,000 km tasks in wave within Scotland.
If you fancy having a look at how we see wave try these two youtube vids. The first is from Aboyne, the second (expletives NOT deleted) is from Camphill, Derbyshire.
YouTube - Glider returning from wave soaring flight through cloud
YouTube - Camphill wave
It's a massive subject and even the experts like John Williams who flys from Portmoak will tell you that after years of exploring it, they are still learning - and he's a bloke who has flown offical 1,000 km tasks in wave within Scotland.
If you fancy having a look at how we see wave try these two youtube vids. The first is from Aboyne, the second (expletives NOT deleted) is from Camphill, Derbyshire.
YouTube - Glider returning from wave soaring flight through cloud
YouTube - Camphill wave
Joined: Jan 2008
Posts: 691
Likes: 0
From: Yorkshire
and what if you cannot out-climb the wave itself or can you always turn back and head the way you came?
Joined: Oct 2005
Posts: 3,218
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From: USA
The strange thing about the lenticular type clouds is that one often sees them where there is absolutely zero turbulence or wind....
Joined: Jan 2008
Posts: 691
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From: Yorkshire
so can you still have mountain waves with no wind?
i see. I should read it as, no lenticular means no wind...
Last edited by liam548; 27th November 2008 at 06:29.
Joined: Sep 2001
Aviation Qualifications: CPL
Posts: 2,787
Likes: 208
From: Toronto
The leading edge of lennies show where the ascending wave air drops below dewpoint; the trailing edge is where dewpoint is regained as the air descends and the moisture is reabsorbed.
While the cloud appears stationary, the air going through is not and there can be considerable shear.
Lennies generally show the peak of the wave; directly below is the rotor.
While the cloud appears stationary, the air going through is not and there can be considerable shear.
Lennies generally show the peak of the wave; directly below is the rotor.
Joined: Jan 2008
Aviation Qualifications: PPL
Posts: 187
Likes: 10
From: Third rock from the sun.
Liam,
Guppy said, 'there is always wind where the lenticular is formed'.
There might not be any wind where YOU are but there IS wind where the lenticulars are!
Guppy said, 'there is always wind where the lenticular is formed'.
There might not be any wind where YOU are but there IS wind where the lenticulars are!
Upto The Buffers
Joined: Apr 2006
Aviation Qualifications: CPL
Posts: 1,112
Likes: 0
From: Leeds/Bradford
They can be seriously unfunny. I flew through a wave about 10mins from LBA clearing the hills south of Dewsbury and it scared the crap out of me. Eyes shaken in sockets, head banged repeatedly on roof despite being strapped in etc... Mentioned it to Leeds Approach who replied, "Funny you should mention that, just had an Embraer on saying he was unable to descend".
Joined: Jan 2008
Posts: 691
Likes: 0
From: Yorkshire
They can be seriously unfunny. I flew through a wave about 10mins from LBA clearing the hills south of Dewsbury and it scared the crap out of me. Eyes shaken in sockets, head banged repeatedly on roof despite being strapped in etc... Mentioned it to Leeds Approach who replied, "Funny you should mention that, just had an Embraer on saying he was unable to descend".
Fleet Manager
Joined: Aug 2006
Aviation Qualifications: CPL
Posts: 7,089
Likes: 2,952
From: Ontario, Canada
I stumbled upon this FAA AC, while looking for something else. I have not read it, I just noticed the title...
(I tried the link, and it worked for me. I case it does not for you it is: AC 00-57 of 1997, Hazardous mountain winds, and their visual indicators)
AC 00-57 Hazardous Mountain Winds and Their Visual Indicators
Pilot DAR
(I tried the link, and it worked for me. I case it does not for you it is: AC 00-57 of 1997, Hazardous mountain winds, and their visual indicators)
AC 00-57 Hazardous Mountain Winds and Their Visual Indicators
Pilot DAR
Joined: Jul 2007
Posts: 610
Likes: 0
From: France
Roll Cloud
In the Southern Hemisphere the weather fronts would normaly come from the South West and proceed to the North East.
On cloud seeding operations we spent a lot of time working ( or playing ) with these fronts.
I can remember one one occasion a roll cloud formed on the leading edge of the air mass. The Cessna 310 sat nicely right on the top of the roll cloud, in the clear, very little turbulence and throttles reduced. A spectacular flight in all ways and it lasted for many miles. The escape plan was to turn left into the clear.
Tmb
On cloud seeding operations we spent a lot of time working ( or playing ) with these fronts.
I can remember one one occasion a roll cloud formed on the leading edge of the air mass. The Cessna 310 sat nicely right on the top of the roll cloud, in the clear, very little turbulence and throttles reduced. A spectacular flight in all ways and it lasted for many miles. The escape plan was to turn left into the clear.
Tmb
Joined: Jan 2006
Posts: 676
Likes: 0
From: london
This is quite a good illustration of the 'upside' of mountain waves.
Grosse frayeur en snowkite
If anyone wants a translation of what the camera man is saying, do feel free to pm me - but I suspect you'll be able to guess.....
Grosse frayeur en snowkite
If anyone wants a translation of what the camera man is saying, do feel free to pm me - but I suspect you'll be able to guess.....
Joined: Jan 2008
Posts: 691
Likes: 0
From: Yorkshire
This is quite a good illustration of the 'upside' of mountain waves.
Grosse frayeur en snowkite
If anyone wants a translation of what the camera man is saying, do feel free to pm me - but I suspect you'll be able to guess.....
Grosse frayeur en snowkite
If anyone wants a translation of what the camera man is saying, do feel free to pm me - but I suspect you'll be able to guess.....
!!!!!!!!!!!!! @@$$!!
