Ryanair pilot assesses snowy braking action!
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As a professional inspector of runways myself, my opinion is that the Ryanair Captain did well.
A runway surface is not homogeneous. Along a single runway, the roughness and ruts (think standing water), gradient (drainage), and even the surfacing type (age, texture) varies.
The measurement of runway contamination/friction is not consistent. It can visual, or by machine. The machine can be accurate or not, it can be in-calibration or not, it can be valid for the conditions or invalid (think contamination depth vs machine calibration depth).
The reporting of runway surfacing condition is not consistent. It can be the average condition, or some statistical treatment such as the worst third, or some commercial practice such as the most optimistic.
The deposition of contamination is not homogeneous. Parts of the runway can be affected by microclimate activity (bursts of rain).
The reporting of contamination is not uniform, nor always to be trusted (loss of face, ignorance, indolence, avarice). The first world is as guilty as the third.
In practice, the system works reasonably. The addition of pilot BA reports is a worthwhile and significant input, where available from a flightdeck with a crew culture that doesn’t worry about loss of face.
For an operation in marginal conditions, where runway contamination is going to be an important factor, and the runway condition is not clearly evident, a visual inspection of the runway is commendable. IMHO the flight crew can make useful and pertinent observation from such an inspection. And IMHO as much or more so than ATC can.
The inspection of the runway is done by vehicle in the interests of safety (visibility, weather protection), communication (radio), and speed (minimum runway occupancy). I would recommend driving the full length of the runway at the carefully chosen speeds of 60 kph, returning at 100 kph. Stop in the first and again in the last third of the runway, and at each stop get out of the vehicle and “kick the dirt”, as the colloquial expression is.
A runway surface is not homogeneous. Along a single runway, the roughness and ruts (think standing water), gradient (drainage), and even the surfacing type (age, texture) varies.
The measurement of runway contamination/friction is not consistent. It can visual, or by machine. The machine can be accurate or not, it can be in-calibration or not, it can be valid for the conditions or invalid (think contamination depth vs machine calibration depth).
The reporting of runway surfacing condition is not consistent. It can be the average condition, or some statistical treatment such as the worst third, or some commercial practice such as the most optimistic.
The deposition of contamination is not homogeneous. Parts of the runway can be affected by microclimate activity (bursts of rain).
The reporting of contamination is not uniform, nor always to be trusted (loss of face, ignorance, indolence, avarice). The first world is as guilty as the third.
In practice, the system works reasonably. The addition of pilot BA reports is a worthwhile and significant input, where available from a flightdeck with a crew culture that doesn’t worry about loss of face.
For an operation in marginal conditions, where runway contamination is going to be an important factor, and the runway condition is not clearly evident, a visual inspection of the runway is commendable. IMHO the flight crew can make useful and pertinent observation from such an inspection. And IMHO as much or more so than ATC can.
The inspection of the runway is done by vehicle in the interests of safety (visibility, weather protection), communication (radio), and speed (minimum runway occupancy). I would recommend driving the full length of the runway at the carefully chosen speeds of 60 kph, returning at 100 kph. Stop in the first and again in the last third of the runway, and at each stop get out of the vehicle and “kick the dirt”, as the colloquial expression is.
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You do not get a brakeing action on this type of contaminated rwy. Quote is from CAA FODCOM Winter OPS 30/2005.
1.3 Braking Action on Dry and Wet Runways and Runways that may be Slippery When Wet
1.3.1 At civil aerodromes licensed for public use with paved runways more than 1200 metres long, periodic surveys of the friction level should be carried out. Provided that these surveys indicate greater than the Minimum Friction Level, good braking action may be assumed when the runway condition is reported as dry, damp or wet (CAP 683 ‘‘The Assessment of Runway Surface
Friction’’). If during routine friction measurements the coefficient falls below the minimum friction level for a continuous portion of the runway for 100 metres or more, the runway will be declared as one that may be slippery when wet. These friction measurements are not correlated directly to any specific aircraft type but are intended as guidelines for aerodrome operators on areas of the runway that require maintenance.
1.3.2 The report of the surface friction coefficients measured during the runway friction survey can be requested from the aerodrome operator. These coefficients will indicate the area of deterioration on the runway which can be as little as 100 metres of degraded surface or, after a prolonged dry
spell, initial rainfall may result in a very slippery condition that affects the whole runway temporarily. However, any performance calculations or adjustments resulting from the dissemination of this information are the responsibility of the aircraft operator and the commander, and not the aerodrome operator.
1.4 Reporting Contaminated Runway Braking Action
1.4.1 Measurement of braking action on contaminated runways is limited to ice (gritted or ungritted) and dry or compacted snow. Braking action will not be measured in slush, uncompacted wet snow or water (more than 3 mm deep) due to the limitations of existing friction measuring equipment.
I say again,You don't have brakeing actions on this type of RWY.
Last edited by alibaba; 17th Mar 2006 at 11:04.
Keeping Danny in Sandwiches
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How about a "poll" as to whether the captain would have been suported by his manager if things hadn't worked out or would they have covered their a*** and given him the sack before he got home?
How would you vote?
How would you vote?
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When Ryanair originally started flying into Skavsta with the 800, I remember a pilot who landed on RW08 BA MED/POOR. During the landing roll he temp lost control of the a/c in an area that had BA zero. He regained control using the recommended technique, changed underpants, then went out with the Saab friction test guys who took the time to explain the following:
To have an average there must be areas below the final reported value. In this case a 100 metres at 0 BA just to the left of the CL. This info was in the Saab drivers report and could have been passed to the pilot on approach if asked for. Just ask for "the comments".
A white/black runway can be deceptive in terms of BA. Snow is grippier than ice.
Bring the a/c to taxy speed as early as possible in the landing rollout.
Unfortunately this captain thought he knew better than the SAS trained guys and ordered them to keep sweeping the runway for his departure. They told him this would be detrimental to BA as it would help shine the surface. He wouldnt listen. They night stopped. No action was ever taken against him, but two engineering pilots were sent out to NYO to learn from the experience. They wrote a great precis from a Saab/runway clearing perpsective which was handed out to RYR pilots at the time.
This LPL pilot may have been equally ignorant or perhaps quite perceptive and versed on slippery/contam runway ops. Maybe he was just passing time and has probably learnt more about contam runways than the majority of posters here will ever know!
The question I ask is why do pilots with the same licence attained through the same system have such varying opinions on such a fundamentally important area? I think the answer lies in licensing/examinations etc that in my day were still concentrating on areas such as Omega nav even though it had been withdrawn!
To have an average there must be areas below the final reported value. In this case a 100 metres at 0 BA just to the left of the CL. This info was in the Saab drivers report and could have been passed to the pilot on approach if asked for. Just ask for "the comments".
A white/black runway can be deceptive in terms of BA. Snow is grippier than ice.
Bring the a/c to taxy speed as early as possible in the landing rollout.
Unfortunately this captain thought he knew better than the SAS trained guys and ordered them to keep sweeping the runway for his departure. They told him this would be detrimental to BA as it would help shine the surface. He wouldnt listen. They night stopped. No action was ever taken against him, but two engineering pilots were sent out to NYO to learn from the experience. They wrote a great precis from a Saab/runway clearing perpsective which was handed out to RYR pilots at the time.
This LPL pilot may have been equally ignorant or perhaps quite perceptive and versed on slippery/contam runway ops. Maybe he was just passing time and has probably learnt more about contam runways than the majority of posters here will ever know!
The question I ask is why do pilots with the same licence attained through the same system have such varying opinions on such a fundamentally important area? I think the answer lies in licensing/examinations etc that in my day were still concentrating on areas such as Omega nav even though it had been withdrawn!
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Originally Posted by Jambo Buana
The question I ask is why do pilots with the same licence attained through the same system have such varying opinions on such a fundamentally important area? I think the answer lies in licensing/examinations etc that in my day were still concentrating on areas such as Omega nav even though it had been withdrawn!
I think your question is excellent. On the instrument exam in the USA I was asked a question about the odd sort of lead in lights at KJFK for the Carnasie approach.
It was more than 15 years before I actually flew to KJFK.
The licensing of all pilots is an odd sort of guess. We call it a license to learn out here.
Some pilots are at their peak of capability the day they get their ATP and go down hill from there. Others are constantly learning and honing their skills.
It takes a rare sort of pilot on their retirment flight to actually be trying to be even better!
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It certainly is rare to find a pilot like that. I guess if we were all perfect there would be no training depts. That would be nice! I havent had a SBY day now for 7 years and have had only 23 non training days in that period!
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I picked up my Contaminated Runway stuff through practical experience with others and careful reading of the company orders and regulations and Performance Manuals. I suppose it depends if the company you are in has that much detail in its publications and much experience operating in adverse weather. However to take apart this poor Captain like this out of obvious ignorance of procedures deserves criticism.
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Originally Posted by Jambo Buana
The question I ask is why do pilots with the same licence attained through the same system have such varying opinions on such a fundamentally important area? I think the answer lies in licensing/examinations etc that in my day were still concentrating on areas such as Omega nav even though it had been withdrawn!
Yes, I agree. This is the question which summarises the 'reason d'etre' for this post. We as pilots need to question the whole system of contaminated rwy perf calcs. I for one (a trainer) have spent a lot of time on this area and have found more "grey" statements in the bibles than I care to think about. It is time to change this from a guessing game into a science. The industry created GPWS against all the odds to reduce CFIT to a minimum, is it not time a drive towards contaminated rwy operations was changed from a guessing game into a science?
The question I ask is why do pilots with the same licence attained through the same system have such varying opinions on such a fundamentally important area? I think the answer lies in licensing/examinations etc that in my day were still concentrating on areas such as Omega nav even though it had been withdrawn!
Yes, I agree. This is the question which summarises the 'reason d'etre' for this post. We as pilots need to question the whole system of contaminated rwy perf calcs. I for one (a trainer) have spent a lot of time on this area and have found more "grey" statements in the bibles than I care to think about. It is time to change this from a guessing game into a science. The industry created GPWS against all the odds to reduce CFIT to a minimum, is it not time a drive towards contaminated rwy operations was changed from a guessing game into a science?
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B.H. I agree in some respects to what you are saying about contaminated calc's being grey in some aspects. The policy and procedures is in the books though for all to read.
The whole purpose of this post though was not to ask technical questions about how you work out contaminated figures.
It was undoubtedly to try and show the Ryanair crew to be acting negligently in some respect unsafe. This is disgusting in my view and I hope this thread has shown the original poster to be lacking in a large amount of cont. experience and knowledge.
The RWY was checked, evidently from what we learn in this thread by airfield ops and then again by the Captain. Cont. figures must have been used in terms of weight and x-wind limits and a V1 reduction made. I would assume that cold weather supplementary procedures was used and that an engine run-up of 70% N1 for 30 sec every 30 min. At this point if the a/c was on the rwy a degree of judgment can again be used to assess the rwy condition.
A JBI meter is useless in these conditions as stated many times over. Hence why you have cont. figures in your manuals!!!
I think this is RYR bashing at its highest and an ideological problem some people have.
I have also noticed KTT has now gone very quite in this post. I think that the Ryanair crew deserve an unreserved apology from you.
The whole purpose of this post though was not to ask technical questions about how you work out contaminated figures.
It was undoubtedly to try and show the Ryanair crew to be acting negligently in some respect unsafe. This is disgusting in my view and I hope this thread has shown the original poster to be lacking in a large amount of cont. experience and knowledge.
The RWY was checked, evidently from what we learn in this thread by airfield ops and then again by the Captain. Cont. figures must have been used in terms of weight and x-wind limits and a V1 reduction made. I would assume that cold weather supplementary procedures was used and that an engine run-up of 70% N1 for 30 sec every 30 min. At this point if the a/c was on the rwy a degree of judgment can again be used to assess the rwy condition.
A JBI meter is useless in these conditions as stated many times over. Hence why you have cont. figures in your manuals!!!
I think this is RYR bashing at its highest and an ideological problem some people have.
I have also noticed KTT has now gone very quite in this post. I think that the Ryanair crew deserve an unreserved apology from you.
As KTT will fly the Airbus soon (I assume), he'll find that t/o performance on the bus is based on contaminant and depth, and apart from crosswind recommendations and disallowing poor BA on icy runways the BA does not affect the performance calcs. If manufacturers cannot standardise perf calcs for contaminated runways all power to a capt who shows this iniative. BTW for those who ask what an investigation will say if you go off a contaminated runway having inspected the runway yourself. Remember the Boeing contaminated performance tables are "ADVISORY ONLY". Just blindly following advisory tables and having an incident will more likely get you into hot water.
Thread Starter
Alibaba,
I still think my post was valid as do a number of others in their response. Do I think it could of been worded better? yes I do. I was wrong in being so accusational.
However, there has been some very educated postings on here subsequent to mine and we all learn from such debates.
My opinion now hasnt changed tho. I accept the reasoning behind the captains actions, but i dont agree with them.
It was a good choice for him because there were no incidents on take-off. Had there been, you can bet your bottom dollar that a similar post would of started on here and not been so gratious towards his decision.
I still think my post was valid as do a number of others in their response. Do I think it could of been worded better? yes I do. I was wrong in being so accusational.
However, there has been some very educated postings on here subsequent to mine and we all learn from such debates.
My opinion now hasnt changed tho. I accept the reasoning behind the captains actions, but i dont agree with them.
It was a good choice for him because there were no incidents on take-off. Had there been, you can bet your bottom dollar that a similar post would of started on here and not been so gratious towards his decision.
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Yes- and your wing could fall off on take off and no doubt you would be slated here. He took established procedure and went out and saw for himself and assessed what contamination was there, and took a legal decision that it was acceptable according to the criteria of the company. Even had there been an incident, it is not automatic that he would have been to blame and what it was about. Take-off incidents happen even in good weather- the real underlying cause is always established. You should not assume that because a dozen other planes stayed sitting with their crews drinking coffee in bad weather they were all automatically right and this Captain was wrong. Sounds to me like he knew and had experience of ops in this weather and carried out a safe, legal operation. Perhaps when you have more bad weather experience and faith in your aeroplane and manuals, you too will have the confidence to do what you are paid to do, even in bad weather- run a safe, legal and efficient operation and do so keeping public transport moving as you are paid to. It's not good enough to just say because there is a bit of snow on the runway 'I'm going to stop everything just in casethere should be a take-off incident and I might get blamed!" Mr. Boeing has done a lot of performance research and testing involving contaminated runway performance, and for a reason. There are so many severe safety factors applied it is as safe an operation as you could ask for. What you have to do is look at your books, and ....er.....possibly go out and assess for yourself! It's what being a professional pilot is about, and taking personal responsibility for your decisions. If it is a fair and reasonable decision, then I think you will find everyone will back you up.
Originally Posted by kick the tires
My opinion now hasnt changed tho. I accept the reasoning behind the captains actions, but i dont agree with them.
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Well the knives were out for the captain in question when I got to work on Monday, having missed all the excitement(?). General feedback was that he took off with no BA reported and 40 metres cleared width. Adding petrol to the flames was the rumour that he was a contract pilot. That's as far as my second hand knowledge goes.
Out of interest, and I suppose I'm asking this having considered Rainboe's input, if the Commander in question showed initiative and professionalism in his decision making, what is to be said of the many captains who elected to stay put? Too conservative? Pessimistic?
Out of interest, and I suppose I'm asking this having considered Rainboe's input, if the Commander in question showed initiative and professionalism in his decision making, what is to be said of the many captains who elected to stay put? Too conservative? Pessimistic?
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I agree with Rainboe 100%. This guy made a decision based on all of the information available. He was probably the only person who knew the actual cleared width and snow depth, and used this, together with his performance manuals, to do the job for which he is paid. The others made their own decisions not to go, and I would never critisize them for that. I am disappointed that 'professional' pilots should slate a fellow pilot without knowing all of the facts.
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I really enjoyed reading this thread which brings back old memories. Having received my PPL, I was determined to go for a commercial. I lived in a small town in eastern Pennsylvania which had an aiport and a grass runway.
I rented the C172 on a clear blue day, but the night before had seen violent thunderstorms and about three inches of rain. This was an uncontrolled airport, but there was a guy in the building that took your flight plan. Actual ATC contact was PHL or ABE. I asked the fellow in the building if the runway was clear of contamination and he said yes.
Sometimes you get that itchy feeling that you should check it out yourself. I started from the takeoff point and walked the line. Right about V1 there were small puddles of water in the grass and 20 yards later there was a very large puddle -- 10 yards wide and 20 yards long. I decided there and then that despite the great weather, I would not be flying that day.
If I had followed the fellow's advice (he was not ATC by any means) I would have not been able to take off, stuck my nose gear in the mud/water, or had an accident -- probably not fatal.
Therefore, whether you're flying a B747 or a Piper Cub, it always pays off to check out the situation personally when any doubts arise.
LatviaCalling
I rented the C172 on a clear blue day, but the night before had seen violent thunderstorms and about three inches of rain. This was an uncontrolled airport, but there was a guy in the building that took your flight plan. Actual ATC contact was PHL or ABE. I asked the fellow in the building if the runway was clear of contamination and he said yes.
Sometimes you get that itchy feeling that you should check it out yourself. I started from the takeoff point and walked the line. Right about V1 there were small puddles of water in the grass and 20 yards later there was a very large puddle -- 10 yards wide and 20 yards long. I decided there and then that despite the great weather, I would not be flying that day.
If I had followed the fellow's advice (he was not ATC by any means) I would have not been able to take off, stuck my nose gear in the mud/water, or had an accident -- probably not fatal.
Therefore, whether you're flying a B747 or a Piper Cub, it always pays off to check out the situation personally when any doubts arise.
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alibaba
I understand that old chap, the no BA and 40m width was just what people were excitedly telling me the next day. I wasn't around on the day in question and have 1/10th of sod all experience on contaminated runways so am making no judgement of the decision. The consensus from guys in a position to comment on his actions appear to support it - fair enough.
I understand that old chap, the no BA and 40m width was just what people were excitedly telling me the next day. I wasn't around on the day in question and have 1/10th of sod all experience on contaminated runways so am making no judgement of the decision. The consensus from guys in a position to comment on his actions appear to support it - fair enough.
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There's a complicated-ish formula for the B747 of variable acceptable cleared width to allow for the wing mounted engines. There are different weight limitations depending on type and depth of contamination as well. I remember for the 747, certain conditions give a weight penalty of 75 tonnes as well as using special tables! It may well be that other types don't have such data which would lead other types pilots to conclude an illegal operation was taking place. I'm interested in the remarks here about comments being made over the radio, and Bitmorerightrudder advised that
<<Well the knives were out for the captain in question when I got to work on Monday, >>
....so where was 'work' and who had the knives out? If Captain Ryanair acted appropriately, is he ever owed some apologies by quite a few people!
<<Well the knives were out for the captain in question when I got to work on Monday, >>
....so where was 'work' and who had the knives out? If Captain Ryanair acted appropriately, is he ever owed some apologies by quite a few people!
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To be somewhat blunt, what would you rather do - sit on your aircraft with the passengers moaning at you because your delayed and nothing seems to be done about it, or take the bull by the horns and examine it yourself, and getting out of the passengers hair at the same time? I know what I would do. 
Horgy
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