The worst case of turbulence?
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The worst type of turbulence? In my humble opinion - Wake Turbulence. This very under rated effect is rarely examined in detail at PPL level by instructors & pilots alike. Make no mistake, this turbulence will kill you. I have been at the pointy end of an airliner and had 2 wake turbulence events. The first was so severe we had 4 uncommanded rolls of 50°-60° aob which we could do nothing about (6 miles behind an Airbus 330), then we were nearly shaken to pieces. Imagine if this was your average Warrior/Cessna.
Please people, if ATC gives you a "vortex wake, recommended spacing 4 miles" etc then please heed it.
CC
Please people, if ATC gives you a "vortex wake, recommended spacing 4 miles" etc then please heed it.
CC
I agree wake turbulence is not well understood and rarely taught unless training from large airports.
The trouble with the guidelines of 4 miles or 6 miles behind the aircraft generating the wake vortices, is that the vortices dissapate with time not distance. In typical light aircraft 90-100kt speeds, 4 miles still gives you well over 2 minutes, and it is very unlikely you will close on the a/c ahead, so the time increases. But should you be following in a a higher performance a/c flying a faster approach , say 160kts to 4 miles, your chances of an upset are much greater, as 4 miles spacing is only about 90 seconds behind the generating aircraft.
The trouble with the guidelines of 4 miles or 6 miles behind the aircraft generating the wake vortices, is that the vortices dissapate with time not distance. In typical light aircraft 90-100kt speeds, 4 miles still gives you well over 2 minutes, and it is very unlikely you will close on the a/c ahead, so the time increases. But should you be following in a a higher performance a/c flying a faster approach , say 160kts to 4 miles, your chances of an upset are much greater, as 4 miles spacing is only about 90 seconds behind the generating aircraft.
Last edited by bingofuel; 12th Jul 2010 at 18:11. Reason: grammar
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bingofuel totally agree.
For example my other "incident" was behind a 744F, we were on a STAR and 35 miles behind this 744 with a 40kt crosswind. We hit the wake of this a/c and all hell broke loose, AP disconnected and it felt like we were flying through a thunderstorm again with uncommanded rolls. It chewed up the back cabin like they were in a washing machine, luckily nobody was hurt but it certainly was not a nice scenario to be in. The point of this one is that we were 35 miles ahead and we had a relatively strong crosswind but still hit it.
For example my other "incident" was behind a 744F, we were on a STAR and 35 miles behind this 744 with a 40kt crosswind. We hit the wake of this a/c and all hell broke loose, AP disconnected and it felt like we were flying through a thunderstorm again with uncommanded rolls. It chewed up the back cabin like they were in a washing machine, luckily nobody was hurt but it certainly was not a nice scenario to be in. The point of this one is that we were 35 miles ahead and we had a relatively strong crosswind but still hit it.
Last edited by Coffin Corner; 21st Feb 2012 at 23:30.
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The interaction between high-level wind and thermals created an unusual wave condition with climbs up to 2000 fpm at 16000 ft and sinks down to -1500 fpm nearby (but absolutely no turbulence).
Cumulus elongaten in lenticular clouds up to (estimated) 22000 ft.
I hit a bump so hard in my KIS that I thought I'd hit another a/c it was that violent. It was a virtually calm wind summers day and I was flying just to the south of Stanstead CTA at about 1000ft agl and 140kts. Everything was reasonably smooth, apart from the typical small lumps associated with differntial heating.
Without warning there was an almighty thump that fisrt pushed me into my seat then tried to throw me out of it. My pax hit the roof and split his head open, I'd have done the same probably but I'm a bit of a short-ass so had further to travel and the belts kept me in. I did smack my legs on the instrument panel though.
At the time, I'd never experienced turbulence like it before in 8000hrs flying so thought I might have hit another a/c or something. On arrival at my destination I was that concerned I did a fly by of the tower to check that the undercarriage looked intact - it was.
I put it down to wake vortex from a departing 'heavy' from Stanstead. I've since discovered that wake vortex can descend several thousands of feet below a heavy aircraft.
JJ
Without warning there was an almighty thump that fisrt pushed me into my seat then tried to throw me out of it. My pax hit the roof and split his head open, I'd have done the same probably but I'm a bit of a short-ass so had further to travel and the belts kept me in. I did smack my legs on the instrument panel though.
At the time, I'd never experienced turbulence like it before in 8000hrs flying so thought I might have hit another a/c or something. On arrival at my destination I was that concerned I did a fly by of the tower to check that the undercarriage looked intact - it was.
I put it down to wake vortex from a departing 'heavy' from Stanstead. I've since discovered that wake vortex can descend several thousands of feet below a heavy aircraft.
JJ
P.S.: World height records in gliders are 12,637 metres (41,459') for a woman and 15,460 metres (50,721')for a man. Both in wave systems.
G
Happened to me in the heatwave of '76. I was flying a glider at about 500' on final when a sudden bang pushed me down violently enough for dirt to rise up from the floor.
Rusty - Which is vastly preferable to dust rising up through the floor!
Jack
Rusty - Which is vastly preferable to dust rising up through the floor!
Jack
Bit of an aside, but what on earth is the difference between men and women that justifies different gliding records?
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Two examples from my past one in a Jet the other in a twin.
Jet was enroute to Nice and we were given severe turbulence between FL 200 AND FL280 which makes a mockery of those who think you are out of danger high
I warned the passengers but not a ripple all the way down into Nice which was embarassing for me and the warning to the PAX.
We flew back empty on the more northerly SID out of Nice. passing 22000 feet all hell let loose with 45 deg wing drops, cupboards flying open. Luckely the jet was slow in the climb as she was almost uncontrollable.
I asked for an immediate climb to FL340 and at the level we were at in the Citation expected a rate of about 1000 fpm we were going up at 3000 fpm and held that all the way through FL300 into smooth air.
The second was in a twin flying UK to Malaga at FL120. I was single pilot and picking my way between two storm cells near Madrid with ground temperatures at 45 degrees.
In clear air between the cells the ASI went in a flash from 155 kts IAS to 70 kts IAS. I punched out the autopilot went for full power forward on the column and NOTHING.
Same attitude same IAS. Nothing I did made any difference and the
aircraft felt as it had flown into a vacuum!!! I had never experienced anything like this before sitting there with over 2000 fpm on the VSI going down like a lift.
At FL090 after dropping 3000 feet the controls came alive. I informed ATC and climbed back to FL120 as if nothing had happened.
So BEWARE
Pace
nb have reported both of these here before
Jet was enroute to Nice and we were given severe turbulence between FL 200 AND FL280 which makes a mockery of those who think you are out of danger high
I warned the passengers but not a ripple all the way down into Nice which was embarassing for me and the warning to the PAX.
We flew back empty on the more northerly SID out of Nice. passing 22000 feet all hell let loose with 45 deg wing drops, cupboards flying open. Luckely the jet was slow in the climb as she was almost uncontrollable.
I asked for an immediate climb to FL340 and at the level we were at in the Citation expected a rate of about 1000 fpm we were going up at 3000 fpm
and held that all the way through FL300 into smooth air.The second was in a twin flying UK to Malaga at FL120. I was single pilot and picking my way between two storm cells near Madrid with ground temperatures at 45 degrees.
In clear air between the cells the ASI went in a flash from 155 kts IAS to 70 kts IAS. I punched out the autopilot went for full power forward on the column and NOTHING.
Same attitude same IAS. Nothing I did made any difference and the
aircraft felt as it had flown into a vacuum!!! I had never experienced anything like this before sitting there with over 2000 fpm on the VSI going down like a lift.
At FL090 after dropping 3000 feet the controls came alive. I informed ATC and climbed back to FL120 as if nothing had happened.
So BEWARE
Pace
nb have reported both of these here before
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It's not just gliding. FAI World Aerobatics Championships (power) has a Men's winner and a Women's winner.
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Quote:
Originally Posted by Jim59
A good question! There are also different championships for men and women at the international level. If I gave my personal opinion it might be thought to be sexist so if there are any lady glider pilots out there we would appreciate your views...
It's not just gliding. FAI World Aerobatics Championships (power) has a Men's winner and a Women's winner.
Originally Posted by Jim59
A good question! There are also different championships for men and women at the international level. If I gave my personal opinion it might be thought to be sexist so if there are any lady glider pilots out there we would appreciate your views...
It's not just gliding. FAI World Aerobatics Championships (power) has a Men's winner and a Women's winner.
If I was female I would refuse competing in a separate class for women. This has happened before in other sports. Annika Sorenstam (Golf), Judith Polgar (Chess) etc.
Got me wondering, it seems that FAI have separate classes for...
Ballooning
Class D gliders
15m gliders
World class gliders
World class gliders
Parachuting
Manpowered (Okay, I can just about understand that one, men do usually have a bit better power to weight - hence different olympic classes.)
Hang gliding
Except that looking closer, they're actually divided into "feminine" and "general" - so effectively there's an open class, and then a separate class for women only.
Seems rather like something out of the 19th century.
G
Ballooning
Class D gliders
15m gliders
World class gliders
World class gliders
Parachuting
Manpowered (Okay, I can just about understand that one, men do usually have a bit better power to weight - hence different olympic classes.)
Hang gliding
Except that looking closer, they're actually divided into "feminine" and "general" - so effectively there's an open class, and then a separate class for women only.
Seems rather like something out of the 19th century.
G
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Seems rather like something out of the 19th century.
).And yes it is far easier for men to pee into a bottle (I should know; I am an expert by now, with flights up to 7hrs) but I gather the chemical (silica gel) alternative levels the field pretty well.
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Apologies for moving back to turbulence, from women-only gliding and pee 
but there's an interesting incident in this month's AAIB report regarding possible effect of wake from a "light" heli on a PA28:
http://www.aaib.gov.uk/cms_resources...WO%2007-10.pdf
but there's an interesting incident in this month's AAIB report regarding possible effect of wake from a "light" heli on a PA28:http://www.aaib.gov.uk/cms_resources...WO%2007-10.pdf
