PDA

View Full Version : Thunderstorm policies please!


Motorola
13th Dec 2004, 07:43
Hi,

I am researching other airline's thunderstorm avoidance policies.

Would appreciate you posting your airline's policy here, i.e. no takeoffs or landings with a TS within 5 miles, avoid cells by 10 miles airborne, etc.

If you don't want to post the airline's name, a country of origin would help.

Thanks.

autoflight
16th Dec 2004, 01:34
Check out the weather policy at BKK! Last time I was there was a NOTAM indicating that the airfield would never be closed for weather by ATC. Assessment of acceptable conditions was a matter for each airline / crew. Significant airlines like Air France, British Airways & Qantas continued to take-off and land during an active severe thunderstorm directly over the field. Give us an inch & we take a mile.
Sometimes to ensure safety, it might be necessary to deviate 50 miles if you are downwind from a tropical CB, but on the upwind side the vertical face is so smooth that 50 metres can be safe. Its not hard to understand why stated distances are usually for guidance only.

LEM
16th Dec 2004, 07:07
Motorola,
Today there is virtually nothing we can add to the aviation culture, when it comes to thunderstorms, windshear, hail strikes etc...

The problem is no longer knowing what to do, but being willing to apply those good basic principles we know very well.

The major problem is with weak captains unable to resist commercial pressures.

If the French captain sees the British one taking off out of BKK with the same airplane, will he be strong enough to say "NEGATIVE, park it. We go later."?

Another big issue is the loss of face problem.

Come on, are you really scared of a few bumps? That's not the end of the world, after all, and we surely don't want to be overzealous! :yuk:


Until the day fleet captains will not sincerely shake your hand for your diversion/huge delay, we'll continue to have pilots having a hard time resisting commercial pressures and loss of face risks.

LEM

Capt Fathom
16th Dec 2004, 10:34
Come on, are you really scared of a few bumps? That's not the end of the world
Have YOU ever been in a thunderstorm? The consequences can be fatal! The final decision rests with the Captain. I have never been patted on the back for departing, nor questioned for delaying a departure due to weather. That's what I am paid for.

LEM
16th Dec 2004, 13:11
Capt Fathom, I hope you got my point, that was ironic, of course we are advocating exactly the same point!

:} :}

HEATHROW DIRECTOR
16th Dec 2004, 13:18
Down to the individual crew, surely? Having seen thousands of bad weather situations in the London TMA I'd suspect that nothing concrete is written down. One crew will go straight through a storm cell without batting an eyelid and another crew behind - same type, same company - will divert round half of southern England. I kid you not!

Same when I was a tower controller at Heathrow - some guys wouldn't think of taking off if there was a cell nearby... they just sat there whilst others did. Some would request turns off the SID; others wouldn't.. It's all Black Magic!

Doors to Automatic
16th Dec 2004, 14:21
Heathrow Director

Did LHR actually close in situations where there was a heavy storm on or near the airport or did it remain open regardless?

alf5071h
16th Dec 2004, 15:17
Heathrow Director, “Down to the individual crew, surely?”, but that is just one of the problems along with errors of judgement, lack of knowledge of the hazards, lack of world experience, associated threats, turbulence, ice, hail, lightning, etc, etc. Spot on LEM

Having penetrated large tropical storms in a civil aircraft suitably equipped for research purposes, I report that Vra only just provides protection against both a full stall and the published ‘g’ limits (plus and minus) all within a 2 sec period, but does little to protect the aircraft composite structures from hail damage or ice accumulation.

Even the most innocuous Cb can spawn a microburst; let alone turbulence, lightning, and hail at considerable lateral distances. We often forget the old-timers advice about ‘humbleys’, bumbleys’, and grumbleys’: avoid, avoid, avoid. 10 nm is a good start, but if you know what the tops are and it's above the tropopause then make it 30 nm. For these large storms, even the more experienced operators in the tropics stay in the hotel.

Many problems stem from the use (misuse) of modern wx radar, enabling crews to clearly see where the weather is; except for overconfidence, poor judgement, and cutting the corner.

Why do we forget so many hard-learnt lessons?

Heathrow Director, IMHO, you ain’t seen nothing yet.

HEATHROW DIRECTOR
16th Dec 2004, 15:39
<<Did LHR actually close in situations where there was a heavy storm on or near the airport or did it remain open regardless?>>

I've never known the airport to close except in some bad snow conditions so, yes, it remained open. Neither ATC nor the Airport Authority have the power to close the airport because of bad weather so far as I am aware.

<<Heathrow Director, IMHO, you ain’t seen nothing yet.>>

And I probable never will, Alf, having been retired for 2 years!. My comments are based on many years of experience - and extreme curiosity!

Happy cumulo-bumpulus!

FullWings
16th Dec 2004, 20:56
Did LHR actually close in situations where there was a heavy storm on or near the airport or did it remain open regardless?I think the main problem (apart from the fact that as HD says, ATC can't close it except for u/s runways) is that ATC in the UK are blissfully unaware of any weather as they don't have it on their screens.

This is a major drawback as most of the airtime on a CB day is taken up with requests for weather avoidance, especially when a storm drifts through one of the holding patterns. It is annoying to get a heading which takes you right through the middle of an ugly red patch - this is the ONE area where I prefer flying in the USA (not that it's the fault of the UK controllers).

Also, not all airborne weather radars are created equal (or even operated in a consistent manner) so everyone sees something slightly different, which must be even more confusing to the audience on the ground...

Capt Fathom
16th Dec 2004, 21:04
Thanks LEM. I did misread your post (the 'loss of face' part). Note to self...RTFQ. :ugh:

Smudger
16th Dec 2004, 21:16
Thunderstorms are fatal, all the above avoidance advice is very good... it's quite simple really, chance your arm with a thunderstorm and you are surrendering your fate and that of your passengers to chance..do not do it. If you cannot go round the storm, turn back. If you are on the ground wanting to take off when there is a storm in the way, don't, until it is plainly safe to do so. I make no apologies for sounding high and mighty, I am a commercial pilot too, well aware of the pressures we face to get the job done. Just respect the weather for what it is; bigger than all of us. (Climbs down off soap box).

FullWings
16th Dec 2004, 21:20
I can't disagree with you there but have you ever flown through the ITCZ on a dark night?

Motorola
17th Dec 2004, 00:54
We use a Collins WRX700.

Light to medium rain sometimes paints red at low altitudes even in CALibrate.

I then have to interpret the echoe shape and guess whether the red is a cell or widespread monsoon type rain.

Anyone else offer advice on how else to combat this apparent over sensitivity at low altitudes?

Hudson
17th Dec 2004, 01:08
For what it's worth. Climbing out from Fiji in a 737-200 for Wallis Island some one hour away. Afternoon trip with low cloud and rain forecast for Wallis. On the horizon on track was the greatest line of black cloud that I have ever seen. It went from horizon to horizon and my guess was from sea level to 40,000 ft plus.

We flew towards this lot and had a closer look at 80 miles on radar. We were in clear air at 27,000 and in continuous moderate turbulence. Radar showed a green mass with flecks of yellow and red and I guessed that severe rain attenuation was taking place.

I got that warning sixth sense feeling that this was not your usual Cb front. Something said don't go any further or someone is going to get hurt. We called ATC at Fiji and got a clearance to return to Fiji which we did. Passengers and crew stayed overnight and departed for Wallis next morning. At Wallis, the weather was fine and there was a lot of water on the airport. No problem with landing.

Turned out that for our ETA at Wallis the previous afternoon the actual winds were 75 knots, torrential tropical rain and runway flooded. The forecast was almost benign but the tropical depression had started with little warning.
One of the better decisions I have made in my career, thank goodness.

25 years on I still can see that cloud formation in my mind and figured I had looked at death. Sorry to appear to exaggerate but it really did scare me.

LEM
17th Dec 2004, 06:48
Hudson, you should have been in command of the French 744 which departed Joburg for Paris some years ago, dispatched with the wx radar INOP!!!! and for a night flight!!!!


That son of a ***** didn't want to send back to the hotel 400 pax, and he figured out he could cross the whole Africa, at night, watching out the window, like Lindbergh did!

The result was a mess, roughly abeam Senegal, if I remember correctly, an emergency diversion to Marseille, and the DEATH of an old lady thrown onto the ceiling.

:yuk:

Hudson
17th Dec 2004, 12:06
LEM. Just goes to show, doesn't it? In those days my company in the Pacific occasionally had problems with lack of spares for weather radar and I have had a few hairy times with u/s weather radar over the Pacific.

Funny thing though was that for years in the Royal Australian Air Force I flew heavy bombers and transports without radar and got beaten up by Cb's and was never unduly alarmed. Where ignorance is bliss, I suppose.

Smudger
17th Dec 2004, 12:46
FullWings,
Yes, many times whilst flying C130 airbridge sorties ASI-MPA. Guess we just got lucky that we were able to avoid the worst but I do know how big and scary those CBs can be.

HEATHROW DIRECTOR
17th Dec 2004, 12:50
<<ATC in the UK are blissfully unaware of any weather as they don't have it on their screens.>>

You're right.. We used to be able to see weather on radar... until we were given "super new technology"!

FullWings
17th Dec 2004, 16:48
<<ATC in the UK are blissfully unaware of any weather as they don't have it on their screens.>>

You're right.. We used to be able to see weather on radar... until we were given "super new technology"!For the life of me I can't see why this facility was removed. The Met. Office has radar coverage of the whole UK now and it would be quite simple to have a quasi-realtime feed to any controller who wanted it. (I can get it on my home PC so...)

I'm sure ATC build up a mental picture of where NOT to send people but only after a lot of unneccessary chit-chat. Must be even more difficult when storms are moving/building. I have to say I have fairly often taken avoiding action then told ATC when I could get a word in edgeways - not the ideal state of affairs. If you guys on the ground could actually SEE what we can up here it would take a bit of stress out of both our jobs...

HEATHROW DIRECTOR
17th Dec 2004, 17:58
<<For the life of me I can't see why this facility was removed. The Met. Office has radar coverage of the whole UK now and it would be quite simple to have a quasi-realtime feed to any controller who wanted it. (I can get it on my home PC so...)>>

But the people who decided what type of radar is to be used are usually not at the sharp end!!

Maybe one of the current controllers can comment, but when I retired there was a display at West Drayton available to supervisors which displayed weather patterns, radar, rainfall, etc. However, this was not available to individual controllers. The cost was astronomical and that's what it's down to - folding stuff. That's why there will soon be no Met Office staff at the UK's biggest airport.

Hopefully someone will say I'm talking tosh...

Doors to Automatic
21st Dec 2004, 16:05
Here is Lauda Air's Policy:

http://www.airliners.net/open.file/738752/M/

:ooh: :eek: :ooh:

RatherBeFlying
21st Dec 2004, 21:51
DTA, That bolt could easily be 10 or more miles away. Long lenses bring the background quite a bit forward.

In the sky, I've seen lightning from 50 miles.

flying minstrel
27th Dec 2004, 23:13
25 years on I still can see that cloud formation in my mind and figured I had looked at death. Sorry to appear to exaggerate but it really did scare me.

Hudson,

Yours is a useful anecdote. Those of us who are building experience can watch where your footsteps led to give us an inkling as to what sort of decision to make in the future, should we find ourselves in a similar predicament.

All the best in the coming New Year:ok:

FM

His dudeness
1st Jan 2005, 12:48
HD:
quote:
That's why there will soon be no Met Office staff at the UK's biggest airport.

Very valid point indeed....as for germanys airports - they are closing or shriking as well. Most forecasts done on computer based models - and getting worse than their human resource made counterparts.

I loved the wx radar screen we had at my homebase, one could judge much bette wether to depart or not and it was just a 2 minutes walk awya from our parking stand. Now gone together with the wx blokes. Stupid WX Terminals brought in, you get an update every 30 to 60 minutes...

Ignition Override
2nd Jan 2005, 03:58
Even taxiing out when a storm gust front hits should make you thinking that parking (wherever Ground suggests) and shutting all engines down is the thing to do, if a return to the gate seems impractical-we have done this more than a few times and it sure saves lots of fuel-we can't afford to kid ourselves about fuel or weather. If there is a fairly strong small thundercell on the approach or departure path, (or even near another runway!) you are really pushing your passengers luck quite far to even try it-never mind your safety record, reputation and career. Would you want your family on such a plane, even if it is flown using FMC/VNAV/LNAV/autothrottle by the most famous national carrier, whose flight crewmembers wear shiny stripes and FAs beautiful, colorful scarves? On a 15-mile final into Raleigh-Durham, NC last summer we noticed the weather getting stronger just to the left of the localizer for runway 5R, but not much radar contour. The line was not solid and not very wide. But even though there were NO large cells right by the airport or by us, the turbulence was becoming constant moderate and we both had an uncomfortable feeling about the rest of the approach-so we spoke up about it and came in from the other side after delay vectors downwind of it, and in the opposite side (ATC suggested this). I broke off an approach in Albany NY simply because of a slight tailwind on ILS approach to the north, well aware it was a wet, short runway (to hell with the schedule). Came in on opposite ILS when mild rainshower went by. Sometimes even wind readouts are not accurate.

Just say something to the other pilot(s), that you don't like the way it looks and/or feels-no matter which seat you are in, even if you are the FE! Don't be silent about an uncomfortable "feeling". It is such silence which can lead to incidents or tragedy, but guys don't want to admit it as often as the lady pilots.

A few years ago, there was a huge cell on the radar, contours or not, barely north of IND airport and we broke off the 25-mile long localizer final and diverted straight to Louisville. It must have grown very fast! Even if we had flown to within a few miles of the airport in mild winds, once we are near the ground and a microburst comes down or a gust front blows out, it could easily be too late and low for recovery. Check previous (NTSB reports) accidents in the US near thunderstorms. Just offhand, I am reminded of JFK, Charlotte/MSY (DC-9), New Orleans/MSY (727), Dallas-FW/DFW (1011): read the FE's remarks about his nervous legs when they entered the turbulence, a few minutes before the crash...). If you really do not like the look, feel or sound of something, this is NOT the time to be like a kid in school, afraid to raise his/her hand to state a problem. A pilot many years ago told me that years before in southeast Asia, he was spit out of a storm almost upside down in an Air America (or CAT?) DC-3, and was one fine pilot when I knew him. Caramar, Delaware Corp, Doublecheck...

:suspect: