Do you really trust that wet runway performance data

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pelmet
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Re: Do you really trust that wet runway performance data

Post by pelmet » Sun Sep 23, 2018 10:30 pm

Rockie wrote:
Sun Sep 23, 2018 10:01 pm
pelmet wrote:
Fri Sep 21, 2018 4:00 pm
I just suggest following regulating authority recommendations.
I’m beginning to suspect you’re a flight sim guy who reads a lot and pretends.
Oh oh, that would mean a flight sim guy knows more about performance than you......as backed up by the FAA. ;)
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Re: Do you really trust that wet runway performance data

Post by Rockie » Mon Sep 24, 2018 4:50 am

Well then, what do you do in the real world today when the properly applied RCAM says you can land safely, but after adding 30-40% as per 2015’s SAFO 15009 you cannot? How exactly does performance expert Pelmet adhere to his own recommendation then?

Explain the steps you personally follow to determine if it’s safe to land on a wet runway Pelmet - in the real world - today. What does your Captain and Chief Pilot say when you decide it’s unsafe to land after you add an additional 30-40% to the approved method of landing distance calculations?

Do you wave 2015’s SAFO 15009 in the air spouting “but, but, but the FAA says...”?

Answer truthfully Pelmet.
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Re: Do you really trust that wet runway performance data

Post by pelmet » Mon Sep 24, 2018 10:43 am

Rockie wrote:
Mon Sep 24, 2018 4:50 am
Well then, what do you do in the real world today when the properly applied RCAM says you can land safely, but after adding 30-40% as per 2015’s SAFO 15009 you cannot? How exactly does performance expert Pelmet adhere to his own recommendation then?

Explain the steps you personally follow to determine if it’s safe to land on a wet runway Pelmet - in the real world - today. What does your Captain and Chief Pilot say when you decide it’s unsafe to land after you add an additional 30-40% to the approved method of landing distance calculations?

Do you wave 2015’s SAFO 15009 in the air spouting “but, but, but the FAA says...”?

Answer truthfully Pelmet.
The reality is that the situation rarely occurs. How often are you landing on a runway with loads of margin....almost always. Sometimes you are close to your performance margin but the weather is usually good. I might get a wet runway perhaps 1 in 20 times. And even when the runway is wet, rarely do we encounter a situation where there is heavy rain(I suppose it varies by carrier and area of operation). And it is much rarer to happen to be landing on a short runway where one is close to performamce limits combined with heavy rain. I don't remember encountering such a situation myself but it obviously happens and likely will sometime.

But in the end, it really is just using a bit of common sense.

So let's look at a real world situation based on an accident. I know, I know....you will say that it was before TALPA but it is a perfect example of not using common sense.

Wet runways, moderate to heavy rain on approach, heavy landing weight, one runway is short, one runway is long. The short one has the ILS, the long one has non-precision approach. Landing performance is within limits for the short runway, but why would you use it. Sure, one can say that the aircraft landed longer than desired but who hasn't floated a bit on landing. Why accept tight margins if an alternative is available with better margins.

I am talking about the Cargojet 727 in YQM a few years ago. Use some logic. All they had to do is choose the longer runway. If the exact same approach had been performed on the longer runway, it would have worked out OK. But that would have involved doing a non-precision approach. I wonder if they would have requested the longer runway if both had an ILS.

http://www.bst-tsb.gc.ca/eng/rapports-r ... 0a0032.pdf

As for what the chief pilot would say if one decided not to land if the crew was not comfortable...I hope at your company, they would say nothing(let us know). As for me, I am just a flight simmer so I don't have to worry about the captain, chief pilot, or anyone else. ;).
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Re: Do you really trust that wet runway performance data

Post by Rockie » Mon Sep 24, 2018 11:16 am

A non-answer. This situation happens whenever the runway is wet and not very long Pelmet. In those cases adding 30-40% (which you conveniently do not address) easily puts you into the unsafe / undoable range. What then? When the numbers say you can, but First Officer performance specialist Pelmet says you can’t, what do your Captain and Chief Pilot say?

Actual cases Pelmet.

What’s that? It’s never happened to you?

What a surprise.....
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Re: Do you really trust that wet runway performance data

Post by pelmet » Mon Sep 24, 2018 11:33 am

Rockie wrote:
Mon Sep 24, 2018 11:16 am
Actual cases Pelmet.
Just gave you one. Short runway, moderate to heavy rain. Performance numbers said OK. Went off the runway at 50 knots while hydroplaning. Probably would have happened using TALPA numbers as well. But if I had been the F/O on that flight where I guarantee you the 30-40% addidive recommended by the FAA showed that it was not possible to land on 06, I would have suggested 10. Actually, I would have anyway. The 727 can be landed at max landing weight on a 6000 foot dry runway but if it is wet and significant rain is falling, why on earth would you not choose the 8000 foot one.

Pelmet...hoping to achieve First Officer status as soon as I get my 1500 hours of flight simming. But at least I know more about performance than Rockie.
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Last edited by pelmet on Mon Sep 24, 2018 11:51 am, edited 1 time in total.

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Re: Do you really trust that wet runway performance data

Post by pelmet » Mon Sep 24, 2018 11:38 am

Rockie wrote:
Mon Sep 24, 2018 11:16 am
This situation happens whenever the runway is wet and not very long Pelmet. In those cases adding 30-40% (which you conveniently do not address) easily puts you into the unsafe / undoable range. What then?
Congratulations, you finally figured it out although obviously not what to do. If heavy rain is falling, I would recommend you choose a different runway, wait for conditions to improve if you have the time, or divert. Apparently, that sort of idea has not entered your mind...scary.
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Re: Do you really trust that wet runway performance data

Post by Rockie » Mon Sep 24, 2018 4:11 pm

You Pelmet, when have you told your captain you didn’t want to land because you’ve added 40% to the correct landing calculation and got scared.

Personal experience, not somebody else’s mishap where you would have heroically ridden in on SAFO 15009 in your vivid imagination and saved the day.
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Re: Do you really trust that wet runway performance data

Post by pelmet » Mon Sep 24, 2018 4:16 pm

.
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Rockie
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Re: Do you really trust that wet runway performance data

Post by Rockie » Mon Sep 24, 2018 4:21 pm

So no personal experience?

Last chance to demonstrate some credibility.
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Re: Do you really trust that wet runway performance data

Post by photofly » Mon Sep 24, 2018 4:36 pm

I'm sorry I just ruined your attempt at the longest uninterrupted two person exchange in AvCanada history.
You both do realize that everyone else checked out some time ago?
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Re: Do you really trust that wet runway performance data

Post by Rockie » Mon Sep 24, 2018 4:39 pm

Don’t care. I’m not talking to anyone else, I’m talking to him. I’d much prefer to have this discussion in an airplane but that’s not likely to ever happen and I don’t own flight sim
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pelmet
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Re: Do you really trust that wet runway performance data

Post by pelmet » Mon Sep 24, 2018 4:43 pm

Rockie wrote:
Mon Sep 24, 2018 4:11 pm
You Pelmet, when have you told your captain you didn’t want to land because you’ve added 40% to the correct landing calculation and got scared.

Personal experience, not somebody else’s mishap where you would have heroically ridden in on SAFO 15009 in your vivid imagination and saved the day.
First of all, whether the situation has arisen in my personal experience is irrelevant. The specific situation has not occurred because the specific conditions have not converged. As I said much earlier, it is a rare case. Are you really stupid enough to think that because a specific situation has not been experienced by me(although there have been holds to wait out weather) that the argument made by myself and the FAA must therefore be invalid? So much for learning from the mistakes of others for future use. You say contact the FAA, I do, then you say that the FAA interpretation is invalid. I think maybe you should explain why you know that a SAFO is invalid when the Air Carrier Division of the FAA says otherwise.

However, as a footnote, there actually was one time when I was seriously concerned about the choice of runway a captain made, spoke up and was very fortunate to have done so. It was over a decade ago on a medium sized jet involving an overweight landing. I was fairly new to jet flying at the time. We were returning to the departure airport a little over 10K above our max landing weight . The airport has an 8000 foot runway and a 10000 foot runway. He chose the one that we usually use, the shorter one. I disagreed and said that I suggest we use the long runway. Guess what? Higher approach speed, long flare, moderate or slightly more braking and we slowed to taxi speed at the 9000 foot mark.

Of course it was a flightsim experience as well(just love the quality of your arguments to back up your opinion a few insults and an occasional threat). Oh well, I know it is immature but I can do the same.

Looks like I learned more about performance than Rockie from flightsimming…...and I am only qualified as an F/O on the flight sim.
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Re: Do you really trust that wet runway performance data

Post by Rockie » Mon Sep 24, 2018 4:58 pm

Correct runway conditions, correct RCAM landing distance that says you’re safe. Except you add 40% and pee your pants thinking you’re going to die so you tell the captain you don’t think you can do it. Personal experience or not Pelmet? Not interested in 10 year old war stories that are not relevant. I’m talking about TALPA RCAM +40%.

Yes or no?

It matters because thousands of people actually do use RCAM every day in real life without somehow running off the end of the runway, surely you must be one of them right? Do you only fly where it doesn’t rain and all the runways are 12,000 feet long?
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Re: Do you really trust that wet runway performance data

Post by pelmet » Mon Sep 24, 2018 5:29 pm

Rockie wrote:
Mon Sep 24, 2018 4:58 pm
Correct runway conditions, correct RCAM landing distance that says you’re safe. Except you add 40% and pee your pants thinking you’re going to die so you tell the captain you don’t think you can do it. Personal experience or not Pelmet? Not interested in 10 year old war stories that are not relevant. I’m talking about TALPA RCAM +40%.

Yes or no?

It matters because thousands of people actually do use RCAM every day in real life without somehow running off the end of the runway, surely you must be one of them right? Do you only fly where it doesn’t rain and all the runways are 12,000 feet long?
I'm simply repeating what the FAA Air Carrier Division says(although you continuously put misinterpretations in there). Since when do you have the authority to override them......maybe you are Rockie FAR Part 5150.


About 45 sectors last year, a few wet runway situations, no heavy rain, mostly good weather(and lots of days off with good layovers). Average runway length guess......11,000 feet. Of course was much different in the good old days.
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Re: Do you really trust that wet runway performance data

Post by Rockie » Mon Sep 24, 2018 5:39 pm

FAA Air Carrier Division says TALPA RCAM. Not TALPA RCAM +40%, +30%, +20% or +10%. TALPA RCAM.

Fly some more sectors Pelmet and do a lot more reading.
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Re: Do you really trust that wet runway performance data

Post by pelmet » Mon Sep 24, 2018 5:59 pm

Rockie wrote:
Mon Sep 24, 2018 5:39 pm
FAA Air Carrier Division says TALPA RCAM. Not TALPA RCAM +40%, +30%, +20% or +10%. TALPA RCAM.

Fly some more sectors Pelmet and do a lot more reading.
More sectors...….that would mean bidding the crappy flights.

As for reading....I like to read statements from the FAA Air Carrier Branch.....

"I assure you 15009 is relevant, as is 16009, and the information of both should be something we all absorb, especially if we are flying outside of this country, and encounter wet runway conditions, etc. I have 10000 hours in three different, and increasing weight, models of the B-737 (mentioned in the 16009), and have experienced the increase in the subject of 15009. I discussed this with the author of SAFO 15009 (he is completing the update also), and he is in agreement with this position. Please let fellow pilots know the SAFO remains in active status, and having been a critical player (ASAP) during American Airline’s Jamaica accident in 2009, conditions can be different than those reported, even with today’s technologies.


Please feel free to give me a call.

Thanks!

bl

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Buddy Lott, Aviation Safety Inspector | FAA
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Thanks for your opinion Rockie. But you are wrong again...and based on the discussion here where the FAA has confirmed my statements, it appears that I know more about performance than you.

Beware of where you get your advice from.
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Last edited by pelmet on Wed Oct 03, 2018 9:22 am, edited 3 times in total.

Rockie
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Re: Do you really trust that wet runway performance data

Post by Rockie » Mon Sep 24, 2018 8:06 pm

You’re welcome. Let me know how it goes.
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Re: Do you really trust that wet runway performance data

Post by Rockie » Wed Oct 03, 2018 9:38 am

What aircraft do you fly, and what is your company's policy regarding this Pelmet?
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pelmet
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Re: Do you really trust that wet runway performance data

Post by pelmet » Wed Oct 03, 2018 9:59 am

I fly flight sims as you have mentioned here more than once. In reality, what type I fly is irrelevant.

But I think you will find most companies just follow whatever procedure that will maximize revenue. We see flight plans with no extra fuel added when the taf says the thunderstorms will only start 30 minutes after scheduled arrival time so obviously there would never be a thunderstorm prior to that exact time(glad we had extra fuel though the other day). Besides, the company will tell you that the occasional diversion is less costly than the money saved by operating thousands of flights on min fuel.

I have seen payloads planned for aircraft assuming that no ice will be picked up on descent(even though it is cloudy in winter) for aircraft type going to short runways that require higher approach speeds and can't legally get in if ice is picked up. I have seen flight planning over countries where military aircraft are being shot down in a war but the notam says that it is safe above a certain altitue(hey, we should avoid thunderstorms by 20 miles laterally but 1000 feet vertically over missiles is OK - and a lot of major airlines did this), and we have seen all kinds of landing performance calculations over the years where numbers created by test pilots on their fifth try went into the performance manual(and reverse is required for the contaminated performance numbers).

So what does the company do....the absolute minimum that satisfies the regulating authority and the shareholders.

https://www.google.com/search?q=ukraine ... Dilfmq6JpM:

You are on your own.
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Rockie
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Re: Do you really trust that wet runway performance data

Post by Rockie » Wed Oct 03, 2018 10:01 am

That doesn't answer either of my questions. Want to try again?
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Re: Do you really trust that wet runway performance data

Post by pelmet » Wed Jul 24, 2019 3:38 am

Does anybody remember this thread.

I started it and the title pretty much sums it up. I made reference to a safety alert for operators issued by the FAA(15009) which recommends under moderate to heavy rain to add a 30-40% margin to the calculated landing distance.

It is interesting to go through the thread. Rockie was insistent that the TALPA method replaced this earlier recommendation and the earlier recommendation of 30-40% was no longer valid even though it was still on the FAA website. A slew of insults followed in what should really be an adult discussion(of course he is not the only one who has reacted this way).

I was told to go ask the FAA and when I did and an inspector from the air transport division confirmed what I said, Rockie said that the inspector basically did not know what he was talking about. More insults followed as you can see on this thread. It is quite fascinating to read through it. Rockie seems to have disappeared but I would like to clear up the incorrect information he provided.

The FAA recently updated the SAFO and it basically says that you cannot always trust the TALPA reports, which is logical if you think about it. If it starts raining heavily, it takes time for a new report to come out. One has to use their own judgement based on whatever information they can gather, and good judgement.

According to the latest FAA guidance....."Discussion: These overruns have occurred on grooved and smooth runways during periods of moderate to
heavy rain. Analysis of these incidents/accidents indicates that the braking coefficient of friction in each case was significantly lower than expected, and that 30 to 40 percent of additional stopping distance may be required if the runway transitions from wet to contaminated based on the rainfall intensity or reported water contamination (greater than 1/8-inch depth). For the operational in-flight landing assessment, determining whether the runway is wet or potentially contaminated is the pilot’s responsibility."

https://nbaa.org/aircraft-operations/sa ... ng-margin/

https://www.faa.gov/other_visit/aviatio ... O19001.pdf
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Re: Do you really trust that wet runway performance data

Post by Eric Janson » Mon Jul 29, 2019 1:41 am

Perhaps an idea to post how things are done where I work (EASA regulations).

Dispatch

Landing distance is factored by 1.67 as a requirement for dispatch. Wet runway adds 15% so the factor becomes 1.92. This only applies in the planning phase.

Inflight

We use the airbus Flysmart app. We note down actual landing distance plus the factored landing distance which gives a 15% margin. This calculation is mandatory for every landing.

In case of emergency we are allowed to disregard the 15% as this can make the difference between having enough runway and not having enough runway.

These distances are very conservative (and used to be a less before the last major revision) based on real world operating experience.
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Re: Do you really trust that wet runway performance data

Post by Rockie » Wed Jul 31, 2019 7:24 am

To answer once again the question posed at the start of this thread...Yes, you trust wet runway landing numbers.

If for any reason in airline operations the PIC suspects the runway is contaminated with standing water because of recent heavy rain they DO NOT arbitrarily add 30-40% to wet runway landing distance as someone here advocates. The PIC is required to use standing water (over 1/8 inch) contaminated numbers. As per the rules pilots can downgrade a runway condition report based on actual observation, but they cannot upgrade it under any circumstance.

If an air carrier PIC arbitrarily adds 30-40% onto every wet landing distance because they "don't trust it" they will unnecessarily end up diverting often and find themselves struggling to explain their flawed logic (not to mention policy violation) to a very unsympathetic Chief Pilot. Operators are required to set out procedures in their operations manual for contaminated runways, and its pilots are required to follow them if they wish to remain employed.

Very simple.
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Re: Do you really trust that wet runway performance data

Post by LETUN » Thu Aug 01, 2019 12:10 pm

Have to agree with Rockie. WET works on wet. That SAFO tells you to consider that the actual runway condition might be different than what you planed at TOD and might require a reassessment. The 30-40% is probably the difference between WET and STANDING WATER XX" depth on the 737 or some other AC.
The event/accident that triggered that SAFO had guys landing with WET figures while there was heavy rain over the field. WX can change rapidly, adjust your plan accordingly.
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Re: Do you really trust that wet runway performance data

Post by pelmet » Thu Aug 01, 2019 3:01 pm

LETUN wrote:
Thu Aug 01, 2019 12:10 pm
Have to agree with Rockie. WET works on wet. That SAFO tells you to consider that the actual runway condition might be different than what you planed at TOD and might require a reassessment. The 30-40% is probably the difference between WET and STANDING WATER XX" depth on the 737 or some other AC.
The event/accident that triggered that SAFO had guys landing with WET figures while there was heavy rain over the field. WX can change rapidly, adjust your plan accordingly.
I think that means you agree with me as well. If the runway is wet but not contaminated, the numbers may very well work out. But the runway report of merely wet, should not be counted on as accurate. One needs to do their own assessment of whether or not the runway report of wet is accurate. It could easily become contaminated with no further official update given to the pilots. That is when your 30-40% is very applicable. Nobody ever stated to always add 30-40% to every wet landing distance calculation or to any TALPA calculation. But the TALPA report may be wrong.
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