Tail strike at Faro
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@Fat Boy Sim,
Ofcourse FLYERSTAR didn't land a plane with 50kts X-wind! Outside limits anyway, so if he still lands at those conditions: "then I hope to God i am never a passenger when you are flying the bus (If you do fly the bus at all). I think its you who would be better off reverting to the old flight sim dear chap."
Kishna, never heard of it either.
Maybe MR FLYERSTAR would be so kind to help us and tell us on which page we can find it in our FCOM's!
Ofcourse FLYERSTAR didn't land a plane with 50kts X-wind! Outside limits anyway, so if he still lands at those conditions: "then I hope to God i am never a passenger when you are flying the bus (If you do fly the bus at all). I think its you who would be better off reverting to the old flight sim dear chap."
Kishna, never heard of it either.
Maybe MR FLYERSTAR would be so kind to help us and tell us on which page we can find it in our FCOM's!
Not that I've ever tried it, but in extremis I would take a shot at landing a C-172 in a 50 kt. X-wind across the runway -- <20 kt. g/s; 200' wide r/w looks doable.
It's the taxi that would scare me
It's the taxi that would scare me
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For all you chaps looking for 'Vias', you may be searching a long time. FCOM 3.04.10 (Supplementary Tech) p 4 is the 4th page of characteristic speeds including VLS etc, and includes a section called 'OTHER SPEEDS'. What is being called 'Vias' by Flyerstar is called 'VAPP TARGET' by Airbus which may explain the discrepancy, and this speed is defined on that page of FCOM. That is what you see displayed to you as the moving magenta bug on your PFD as the target speed, and will always be equal or greater than VAPP on the Perf Approach speed depending on the prevailing conditions.
Flyerstar - I do not accept that I am wrong. In order to provide protection for as many cases as possible, the Airbus is effectively calculating 4 possible approach speeds and uses the highest of these 4 as the approach speed target. The lowest of these 4 speeds is guaranteed to be never less than VLS+5. Each of these 4 cases relates to a specific potential 'threat' and is effectively doing the thinking for the pilot for him where in other aircraft the pilot would add a certain number of knots to the approach speed. Because GSmini is never shown to the pilot anywhere in the MCDU (even though it is hiding in there), you do not know exactly what the VAPP TARGET will be (unless of course you have researched it beforehand using a spreadsheet or some similar program!). When you have researched it you will see that there are cases where you can effectively 'deceive' the system and negate these protections.
The whole idea that you are protected under all conditions is only true if the Tower Wind is not too high. I accept in most conditons you are correct, but there are certain specific conditions when that is not the case. They all relate to a strong wind being present which then subsides almost instantly near the ground - ie a gust. The first case is the circling approach onto a runway where you have not activated the secondary flight plan when a strong wind exists. If you then circle onto the reciprocal runway and the gust disappears rapidly you will have no protection whatsoever from groundspeed mini and you will lose energy in a big way with all the attendant consequences. Another case I came across in my FO days was ex-Boeing captains updating the tower wind on approach with the last wind from ATC. This is potentially a very serious error as if it was a big value you will decrease the VAPP TARGET and also unwittingly decrease GSmini. That is OK as long as the big wind does not rapidly disappear near the ground but if it does you will again have a low energy situation. The final case where you can have a problem is where you have a strong steady wind that is big (ie 30kts+) and you put that into the tower wind. You are saying to the aircraft that the tower wind is always there - which is fine if it is. If there is a rapid loss of wind near the ground (as we all know can happen) then the low energy situation will arise again.
So in summary, you will always be OK as long as the big winds don't disappear near the ground, but if they do you can and will have a very firm landing if you have a high tower wind. Dare I say it that if you have a spreadsheet or the like to test all these different cases you will see that what I am saying is correct.
Flyerstar - I do not accept that I am wrong. In order to provide protection for as many cases as possible, the Airbus is effectively calculating 4 possible approach speeds and uses the highest of these 4 as the approach speed target. The lowest of these 4 speeds is guaranteed to be never less than VLS+5. Each of these 4 cases relates to a specific potential 'threat' and is effectively doing the thinking for the pilot for him where in other aircraft the pilot would add a certain number of knots to the approach speed. Because GSmini is never shown to the pilot anywhere in the MCDU (even though it is hiding in there), you do not know exactly what the VAPP TARGET will be (unless of course you have researched it beforehand using a spreadsheet or some similar program!). When you have researched it you will see that there are cases where you can effectively 'deceive' the system and negate these protections.
The whole idea that you are protected under all conditions is only true if the Tower Wind is not too high. I accept in most conditons you are correct, but there are certain specific conditions when that is not the case. They all relate to a strong wind being present which then subsides almost instantly near the ground - ie a gust. The first case is the circling approach onto a runway where you have not activated the secondary flight plan when a strong wind exists. If you then circle onto the reciprocal runway and the gust disappears rapidly you will have no protection whatsoever from groundspeed mini and you will lose energy in a big way with all the attendant consequences. Another case I came across in my FO days was ex-Boeing captains updating the tower wind on approach with the last wind from ATC. This is potentially a very serious error as if it was a big value you will decrease the VAPP TARGET and also unwittingly decrease GSmini. That is OK as long as the big wind does not rapidly disappear near the ground but if it does you will again have a low energy situation. The final case where you can have a problem is where you have a strong steady wind that is big (ie 30kts+) and you put that into the tower wind. You are saying to the aircraft that the tower wind is always there - which is fine if it is. If there is a rapid loss of wind near the ground (as we all know can happen) then the low energy situation will arise again.
So in summary, you will always be OK as long as the big winds don't disappear near the ground, but if they do you can and will have a very firm landing if you have a high tower wind. Dare I say it that if you have a spreadsheet or the like to test all these different cases you will see that what I am saying is correct.
Last edited by Norman Stanley Fletcher; 25th Jun 2004 at 10:53.
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Garbage in, Garbage out.
The ATIS wind maybe 30min to 1hr old when input into the performance page at TOD and then its another 20 min to the runway, minimum , adds up to an 'old wind'.
Tower reported wind on approach, unless prefixed otherwise, is generally required to be that averaged over the last 2 minute period, with the gust appended as appropriate.
Unlike NSF , I would suggest you are far better off, and that its perfectly reasonable to update the performance page with the most recent tower wind report, ( not the gust component) for more accurate Vapp / GS Mini computations.
Anybody who thinks that the speed target calculation is going to afford them adequate protection in all circumstances below 400' AGL, just when you really need it, should revisit VOL 1.
The ATIS wind maybe 30min to 1hr old when input into the performance page at TOD and then its another 20 min to the runway, minimum , adds up to an 'old wind'.
Tower reported wind on approach, unless prefixed otherwise, is generally required to be that averaged over the last 2 minute period, with the gust appended as appropriate.
Unlike NSF , I would suggest you are far better off, and that its perfectly reasonable to update the performance page with the most recent tower wind report, ( not the gust component) for more accurate Vapp / GS Mini computations.
Anybody who thinks that the speed target calculation is going to afford them adequate protection in all circumstances below 400' AGL, just when you really need it, should revisit VOL 1.
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Hi sorry for not replying earlier.
Vias is what NSF told you thanks NSF(i never questioned the fact that you know the books :-), also known as the Approach Speed Target(aka IAS target), which we sometimes refer to it as VIAS and which is the speed which is shown by the magenta bug.
Sorry if i misled you by refering to it as VIAS.
As NSF said, the speed on the bus will never be lower than VLS+5 so you can say that one is always guaranteed protection for low energy. I will have a look at the spreadsheet that NSF kindly sent me tomorrow morning.
And yes the bus can be landed in a x-wind gusting 50 kts for all you punters out there whose main hobby on this forum is to slander.
@Carloss - 50kts is not outside limits, the x-wind limit on the bus is what has been demonstrated by the test pilot and given as 33 gusting 38kts, (FCOM 1), however there is no upper limit for x-wind. And anyway stop being an idiot.....maybe we all learn something from this.....i got me flight sim...let me have a go......
Vias is what NSF told you thanks NSF(i never questioned the fact that you know the books :-), also known as the Approach Speed Target(aka IAS target), which we sometimes refer to it as VIAS and which is the speed which is shown by the magenta bug.
Sorry if i misled you by refering to it as VIAS.
As NSF said, the speed on the bus will never be lower than VLS+5 so you can say that one is always guaranteed protection for low energy. I will have a look at the spreadsheet that NSF kindly sent me tomorrow morning.
And yes the bus can be landed in a x-wind gusting 50 kts for all you punters out there whose main hobby on this forum is to slander.
@Carloss - 50kts is not outside limits, the x-wind limit on the bus is what has been demonstrated by the test pilot and given as 33 gusting 38kts, (FCOM 1), however there is no upper limit for x-wind. And anyway stop being an idiot.....maybe we all learn something from this.....i got me flight sim...let me have a go......
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Never stop learning that's why I asked where I could find it. 
@FLYERSTAR…Who said I was talking about the FCOM? I know what's in the FCOM. Don't know for which company you are flying for but I'm sure they have some limits, probably not far from what is demonstrated...
@FLYERSTAR…Who said I was talking about the FCOM? I know what's in the FCOM. Don't know for which company you are flying for but I'm sure they have some limits, probably not far from what is demonstrated...
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Flyerstar,
I have tried this today in a (not the microsoft variety) CAE level D sim. Three of us with a total of 15000hrs on type all had a shot and we could not keep the wee rascal on the runway with the wind set 80degs off at 33kts gusting 50. We appeared to run out of rudder control, great fun though!!
I have tried this today in a (not the microsoft variety) CAE level D sim. Three of us with a total of 15000hrs on type all had a shot and we could not keep the wee rascal on the runway with the wind set 80degs off at 33kts gusting 50. We appeared to run out of rudder control, great fun though!!
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I think that your aircraft insurer might be interested to know if you are landing in winds outside of max demonstrated.
Flyerstar, you speak like somebody who has been a trainer on the airbus for years but I notice from your profile that you have a frozen ATPL.
Flyerstar, you speak like somebody who has been a trainer on the airbus for years but I notice from your profile that you have a frozen ATPL.
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radnav
If you update the tower wind from the last report you are well on the way to coming a cropper and it is potentially a serious error of judgement. Contrary to all your instincts, if you put in a higher tower wind (resolved along the runway axis) you will lower the target approach speed. It is perfectly possible that ATC have given you a short term wind, which in theory is what you want. The problem is that the tower wind is basically there to enable you to fly at as low an approach speed as is safe. You are saying to the system that the tower wind is always there and therefore you do not need to worry to much about it and it is only gusts that should concern you. Remember, a gust in Airbus terms is the difference between the tower wind and the actual wind calculated by the IRS. If the tower wind is high because you put in the last value from ATC then you are telling the system that anything up to that value is not a gust. If that wind subsequently disappears quickly you will have an instantaneous loss of energy which the autothrust may not be able to react to quickly enough. A low tower wind is therefore a protection. As I have said before there is clearly a balance but great caution should be exercised in puting in the last wind from ATC as it can and does lead to low energy situations. Having said that, if your tower wind is 10 knots or less it does not matter what wind or direction you put in - it will never alter the target approach speed. Hence messing around with the tower wind in light and variable conditions is an unnecessary acitivity as nothing changes.
If you update the tower wind from the last report you are well on the way to coming a cropper and it is potentially a serious error of judgement. Contrary to all your instincts, if you put in a higher tower wind (resolved along the runway axis) you will lower the target approach speed. It is perfectly possible that ATC have given you a short term wind, which in theory is what you want. The problem is that the tower wind is basically there to enable you to fly at as low an approach speed as is safe. You are saying to the system that the tower wind is always there and therefore you do not need to worry to much about it and it is only gusts that should concern you. Remember, a gust in Airbus terms is the difference between the tower wind and the actual wind calculated by the IRS. If the tower wind is high because you put in the last value from ATC then you are telling the system that anything up to that value is not a gust. If that wind subsequently disappears quickly you will have an instantaneous loss of energy which the autothrust may not be able to react to quickly enough. A low tower wind is therefore a protection. As I have said before there is clearly a balance but great caution should be exercised in puting in the last wind from ATC as it can and does lead to low energy situations. Having said that, if your tower wind is 10 knots or less it does not matter what wind or direction you put in - it will never alter the target approach speed. Hence messing around with the tower wind in light and variable conditions is an unnecessary acitivity as nothing changes.
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NSF,
The effects of sudden wind variations close to the ground apply equally to all types of aircraft and the affect can be just as significant. Just making up your own wind by sticking your finger out the window ain't gonna help much. Thats why you always have the option of increasing Vapp minimum on the Perf. page, or indeed using selected speed just like the good 'ol days.
Still at the end of the day its whatever works for you. At least you have thought about it.
But just exactly how do you figure out your wind input, or do you always just put in 0/0 wind.
Cheers.
flyerstar,
50 kts X/wind on the runway, gutsiest move I ever heard of mav.
The effects of sudden wind variations close to the ground apply equally to all types of aircraft and the affect can be just as significant. Just making up your own wind by sticking your finger out the window ain't gonna help much. Thats why you always have the option of increasing Vapp minimum on the Perf. page, or indeed using selected speed just like the good 'ol days.
Still at the end of the day its whatever works for you. At least you have thought about it.
But just exactly how do you figure out your wind input, or do you always just put in 0/0 wind.
Cheers.
flyerstar,
50 kts X/wind on the runway, gutsiest move I ever heard of mav.
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Seriously no one is a maverick. Far from it. I am trying hard to recall where the place was and finding an actual Metar but it was some time ago. If i recall well it was ZRH. Anyone landed in EGLL 3 days ago?
@king of luton what was frozen has thawed 
@Fat boy slim That must have been real fun! I definitely recall that the wind was blowing that much at least till very short finals and approx 60deg off and variable.
@king of luton what was frozen has thawed
@Fat boy slim That must have been real fun! I definitely recall that the wind was blowing that much at least till very short finals and approx 60deg off and variable.
<<50kts is not outside limits, the x-wind limit on the bus is what has been demonstrated by the test pilot and given as 33 gusting 38kts, (FCOM 1)>>
Flyerstar, if you do have an FCOM 1 look up page 3.01.20 above your demonstrated max crosswind figures.........
It says "GENERAL LIMITATIONS". Would not like to argue that one in a court of law.
Flyerstar, if you do have an FCOM 1 look up page 3.01.20 above your demonstrated max crosswind figures.........
It says "GENERAL LIMITATIONS". Would not like to argue that one in a court of law.
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Next LPC/OPC try it. Once on the ground you will loose rudder authority & drift off into wind.
Quite clearly these figures are in the limitations section for the aeroplane. Do you expect your employer to back you under these circumstances? If so, you are in for a very disappointing day!
Quite clearly these figures are in the limitations section for the aeroplane. Do you expect your employer to back you under these circumstances? If so, you are in for a very disappointing day!
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Even a level D sim is not a reliable indication of what the aeroplane will do in a strong cross wind! It is programmed using the aircraft manufacturer’s data. Out of interest next time your in the sim try setting the cross wind to 3 or 4 knots above the max cross wind limit on a wet runway. You will find it very hard to keep it on the runway as the aircraft slows down, ends up doing a very nice skid and comes to rest pointing the wrong way. Also worth trying with the park brake on, easier to keep strait with all the tyres burst fairly sure that would not be true in the real aeroplane!
The other one that is fun to try is aircraft parked with park brake set, contaminated runway; increase cross wind and at around 80 kts aircraft disappears across the airfield at a fair rate of knots.
All of the above said I agree with the view landing outside the manufacturers published limits is a risky affair and can result in long term damage to your career. Although as has correctly been pointed the cross wind limits are demonstrated not hard limits, you would not have a leg to stand on if you landed outside these limits and came off the runway.
The ATR 42 had a demonstrated cross wind limit of 45 kts I seem to recall but would not like to have put that to the test!
The other one that is fun to try is aircraft parked with park brake set, contaminated runway; increase cross wind and at around 80 kts aircraft disappears across the airfield at a fair rate of knots.
All of the above said I agree with the view landing outside the manufacturers published limits is a risky affair and can result in long term damage to your career. Although as has correctly been pointed the cross wind limits are demonstrated not hard limits, you would not have a leg to stand on if you landed outside these limits and came off the runway.
The ATR 42 had a demonstrated cross wind limit of 45 kts I seem to recall but would not like to have put that to the test!
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Airbus and Boeing have always refused to provide sim makers with data for situations that have not been flight-tested. The classic example is reverser deployed in flight. The airframers would be in a good position to make informed estimates for many of these abnormal situations, but unfortunately the guessing is left to the sim builders, who are not in a very good position to make those estimates. The general trend is to have the sim become unflyable once you go out of limits.
