Snow-covered flaps before takeoff

[valvelifter]

I was a passenger flying out of Chicago last week and due to snow, our 777 was de-iced at the terminal. We pushed back, engines started, and were on our way to the runway for takeoff. When the flaps were extended, I noticed a patch of snow covering about 20% of the flap, close to the inside part of the flaps, just under the spoiler. This surface was obviously not exposed since the flaps were at the 0 degrees position when the aircraft was de-iced. Now, not knowing if it was pure snow or if there was a layer of ice under the snow, I asked the flight attendant about this when she passed by. She seemed concerned, and went off to get a colleague of hers, who also looked concerned and eventually had the aircraft stop in the middle of taxiing because the first officer came in the back to check himself. So obviously, the pax on board were concerned because it's not often that the flight crew will come back to check something on the wing so close to takeoff. When the first officer was taking a look, he seemed a little unsure, and said things like "hmmm, well" and "well, we did de-ice so it should be OK". So he said he would ask the Captain and left, and five minutes later, the capt. announced to the crew to be prepared for T/O.

During the takeoff run, the snow did blow away and the rest of the flight was uneventful. I was not sure if the other wing had the same snow. The first officer did not check the other wing.

My question is: should we have gone back to get it verified? Is it normal for this? I don't remember seeing snow on flaps after de-icing but I don't travel too much in the winter. The flight was already late due to storms in some parts of the US, including Chicago, but I hate to think that the flight crew took a small chance since they were under pressure to get the aircraft in the air. The flight attendant did come back and thank me for mentioning this and told me I did the right thing. She said she didn't care that we took off 20 minutes later because of my concern.

[shitdisturber]

I'm guessing that since you said it was five minutes after the F/O left that the Capt made the prep for takeoff announcement that there was a discussion on the company frequency before the departure. Apparently somebody decided all was well. Still and all as the F/A said, you did the right thing bringing it to her attention.

[i-vtec]

so, your "THAT" guy are you?

[Nark]

so, your "THAT" guy are you?

So you're the guy who knows everything.

[Stu Pidasso]

You can Take-off with a foot of snow on the wings (figuratively,) as long is it is not adhering to the surface.

eg - Cold ambient temperature and dry snow.

In this case the contaminant blew off the flaps, which is perfectly okay.

[Maynard]

Besides....it's just the inboard part of the wings...it doesn't actually produce lift, just there to make you feel better......

[HS-748 2A]

Basically, 99.9% of all the de-ice fluid ever sprayed on a Boeing was a total waste of time and money; pure politics.

Boeings of all stripes are nearly unaffected by icing.

To my knowledge, there has never been a takeoff crash of a Boeing due to wing ice contamination.

People will cite the 1982 crash in the Potomac as having been caused by wing-ice contamination.

Wing-ice was only a very minor factor in that case.

The P.F.'s failure to open the throttles beyond a falsely high-reading EPR was the ultimate cause.

Failure of the P.N.F. to dissuade the P.F. from his automated response was also a significant contributing factor.

A little bit of junk on the flaps on a 777 wouldn't worry me a bit.

An F-28 however, or a Cessna Caravan... Put your head between your knees and kiss your ass goodbye.

'48

[BTD]

Wing-ice was only a very minor factor in that case.

While I don't disagree with you about the lack of power being a primary cause to this accident. As mentioned in the accident report, the wing ice was more than a very minor factor in this case.

If there snow/ice wasn't present the aircraft would most likely not have crashed. If they had the correct power setting the aircraft also would most likely not have crashed.

Also your PNF/PF references are backwards. The F/O was the PF attempting to to persaude the capt PNF something was wrong.

http://libraryonline.erau.edu/online-fu ... R82-08.pdf

Therefore, the Safety Board concludes that the activation of the aircraft’s
stickshaker and the onset of stall buffet at airspeeds significantly higher than the
airspeeds at which those events would theoretically oczur-.are-positive evidence-that snow
or ice was adhering to .-t.h -e-~airplan- e-~and-degrading its-aerodynamic performance.

Aircraft Capability to Climb or Accelerate After Liftoff.--The increased drag
of the aircraft caused by the snow contamination was a major factor in this accident,
particularly when combined with the lower-than-normal takeoff thrust brought about by
the erroneous EPR indication.

The Safety Board interprets the captain’s comment, “Easy,” closely following
the “Vee one” callout as a typical reaction to an abnormally abrupt or nose-high rotation.
Based upon the experiences reported by other B-737 operators under similar
environmental conditions, the Safety Board concludes that the airframe snow or ice
contamination produced a noseup pitching moment during rotation and liftoff which was
not or could not be immediately countered by the pilot controlling the aircraft and which
aggravated the subsequent deterioration of the performance of the aircraft.

The National Transportation Safety Board determines that the probable cause
of this accident was the flightcrew’s failure to use engine anti-ice during ground operation
and takeoff, their decision to take off with snow/ice on the airfoil surfaces of the
aircraft, and the captain’s failure to reject the takeoff during the early stage when his
attention was called to anomalous engine instrument readings.

The accident reports are all out there online.

BTD

[HS-748 2A]

your PNF/PF references are backwards. The F/O was the PF attempting to to persaude the capt PNF something was wrong.

I'll take that. I hadn't actually looked at the report for a long time.

'48

[BingBong]

An F-28 however, Put your head between your knees and kiss your ass goodbye.

What do you mean by this? Care to re-phrase

[albertdesalvo]

I would imagine he's referring to the crash of Air Ontario Flight 1363 in Dryden, a very well known accident involving the F-28 and icing.

Edited to add: There have been several other F-28 crashes attributed to icing. Google is your friend.

[slowstream]

I can't speak to Boeing but I also can't see it being a lot different from the CRJ900. When you are in a condition of moderate to heavy snow and collect snow on the upper portion of the flaps during landing, roll out and just prior to raising the flaps you, then you are required to lower your flaps and spray type I to remove all contaminants. Then you raise your flaps to the desired T/O setting and commence with Type IV spray.

The CRJ900(even more so with the 700) likely has similar thrust to weight ratio as many Boeings, so as I said I can't see it being a lot different. Someone correct me if I'm wrong.

[bezerker]

I believe the airfoil design is more important than thrust to weight ratio when it come to icing effects.

Aircraft: Wing Root Airfoil: Wing Tip Airfoil:

Boeing 737-200 BAC 449/450/451 BAC 442
Canadair Regional Jet Canadair 13.2% Canadair 10%

This post is interesting though. Not that any pilot is incapable of making an incorrect decision, but I wonder about that 777 Captain. Do you think he was a risk taker? A poor pilot? Maybe he didn't have a lot of total time and this was his first time dealing with surface contamination. Or maybe his ice training had expired.

Or I will put it another way by quoting a legendary statement, "What the f@ck do you know about Boeing wing deicing?"

[bizjets101]

If your not on a DC-9-15 series, or an F-28/F-100 chances are you have zero to worry about.

Only two Boeing's have had problems regarding icing on takeoff - 6 weeks apart - a Sterling B727 in Gander (no one injured) but aircraft substantially damaged and the Air Florida in Washington - both had false air -speed indications and neither direct cause was the snow on the wings. Both incidents were 28 years ago!!!

The only mystery crash of a large commercial airliner due to wing contamination was the very controversial crash of the Arrow Air in Gander; Click Here. 25 years ago!!!!

Make that less than zero to worry about on the B777 - unless your
landing at Heathrow - but that's another story!!!! Click Here.

G-YMMM B777 British Airways LHR.jpg (131.96 KiB) Viewed 2232 times

[slam525i]

I think when we look at incidence rate of Boeings having icing related accidents, we should be careful not to mistaken correlation with causation. I'm sure most operators of Boeing aircraft have a well established de-icing SOP, which may the the reason why Boeings don't have many icing related accidents, rather than airfoil design. I'm not saying it's not the airfoil design, I'm just saying we shouldn't assume it is. My gut feeling is if everyone stopped de-icing Boeings completely, we'd start seeing a lot more accidents.

[pika]

I'm sure most operators of Boeing aircraft have a well established de-icing SOP

This is your assumption (which you pointed out we should not do).

I can confirm that not all Boeing operators have well established SOP's in regard to cold weather operations.

[BTD]

Only two Boeing's have had problems regarding icing on takeoff - 6 weeks apart - a Sterling B727 in Gander (no one injured) but aircraft substantially damaged and the Air Florida in Washington - both had false air -speed indications and neither direct cause was the snow on the wings. Both incidents were 28 years ago!!!

Biz, I'm sorry this is not directly related to your quote, but somewhat it is. I kind of have to vent.

Why is it that people cannot get the details of an accident accurate when there are 100+ page documents devoted to each major accident in US, Canadian, and European history for the last 40 years. Its all out there online.

I already referenced the Air Florida accident above and provided a link to the report above. There was no Airspeed false reading in the Air Florida Accident and the ice on the wing WAS one of the direct causes to the accident. There was another (the power setting used for take-off).

Please everyone before using an accident to establish your argument make sure that you have your facts correct. With a 30 sec search we can all confirm the facts and if you are wrong, your credibility goes out the window for that argument.

I have read and can find details on most of the major airline accident reports in the US and Canada in a matter of mins. I do not recall the 727 one you reference above. Perhaps I have not read it. But it is difficult to take your word for it, because every thing quoted so far on the Air Florida accident has been false.

I appreciate your contributions to the accident forum, because this is how we all learn. But make sure facts are accurate. The best way to do that is include the quotes in your posts from the report itself.

I think this is the only rant I've ever had in 5 years here, but it is a major frusturation for me.

Its so simple.

BTD

[LegoMan]

Only two Boeing's have had problems regarding icing on takeoff - 6 weeks apart - a Sterling B727 in Gander (no one injured) but aircraft substantially damaged and the Air Florida in Washington - both had false air -speed indications and neither direct cause was the snow on the wings. Both incidents were 28 years ago!!!

Biz, I'm sorry this is not directly related to your quote, but somewhat it is. I kind of have to vent.

Why is it that people cannot get the details of an accident accurate when there are 100+ page documents devoted to each major accident in US, Canadian, and European history for the last 40 years. Its all out there online.

I already referenced the Air Florida accident above and provided a link to the report above. There was no Airspeed false reading in the Air Florida Accident and the ice on the wing WAS one of the direct causes to the accident. There was another (the power setting used for take-off).

Please everyone before using an accident to establish your argument make sure that you have your facts correct. With a 30 sec search we can all confirm the facts and if you are wrong, your credibility goes out the window for that argument.

I have read and can find details on most of the major airline accident reports in the US and Canada in a matter of mins. I do not recall the 727 one you reference above. Perhaps I have not read it. But it is difficult to take your word for it, because every thing quoted so far on the Air Florida accident has been false.

I appreciate your contributions to the accident forum, because this is how we all learn. But make sure facts are accurate. The best way to do that is include the quotes in your posts from the report itself.

I think this is the only rant I've ever had in 5 years here, but it is a major frusturation for me.

Its so simple.

BTD

Majority of people have a life and dont spend their free time sifting through hundreds of pages of documentation to know the real facts of a crash. That's about the best answer I could give you.

[BTD]

727 at Gander

http://aviation-safety.net/database/rec ... 19811216-0

PROBABLE CAUSE: Decreased performance due to erroneous engine gauge readings caused by icing of the engine inlet pressure probes.

Only mention to airspeed in the synopsis is the F/O rotating early due to the end of the runway approaching.

Reference to Legoman Above:

Yeah, I get that, and have no problem with it. But when making an argument and using facts as your centre point, you should have the facts correct. For all it takes 30s to confirm them. It ties into the CARs stuff we've been seeing in the Flight Training forum.

Statement made: No Boeings have crashed due to snow on the wings

Fact: The above statement is false, or at least not complete.

[BingBong]

I would imagine he's referring to the crash of Air Ontario Flight 1363 in Dryden, a very well known accident involving the F-28 and icing.Google is your friend.

Thanks chief...I never would have thought to use a search engine.
I was calling out the poster (read: probable cct jockey) and their disrespect to the situation.
Should HS748 wish to discuss this further...I'd be glad to fly out to whatever you are located and discuss this in person.

[bizjets101]

Biz, I'm sorry this is not directly related to your quote, but somewhat it is. I kind of have to vent.

“ 15:59:32 CAM-1 Okay, your throttles.

15:59:35 [SOUND OF ENGINE SPOOLUP]

15:59:49 CAM-1 Holler if you need the wipers.

15:59:51 CAM-1 It's spooled. Real cold, real cold.

15:59:58 CAM-2 God, look at that thing. That don't seem right, does it? Uh, that's not right.

16:00:09 CAM-1 Yes it is, there's eighty.

16:00:10 CAM-2 Naw, I don't think that's right. Ah, maybe it is.

16:00:21 CAM-1 Hundred and twenty.

16:00:23 CAM-2 I don't know.

16:00:31 CAM-1 Vee-one. Easy, vee-two.
”

—Transcript, Air Florida Flight 90 Cockpit Voice Recorder Click here to listen.

I hadn't planned on hijacking the thread, the original poster inquired about B777's - however subsequent poster commented on Boeing's and the Air Florida specifically.

So as not to hijack the thread, I included one sentence - as opposed to commenting on 100 pages of crash info.

However what I inferred was the airspeed of the Air Florida did not jive with the engine readings, and in the probable cause was listed as; the captain’s failure to reject the takeoff during the early stage when his attention was called to anomalous engine instrument readings.

The pilots could feel the power and speed where not there, the engine pressure ratio (EPR) thrust indicators provided false high readings — when the pilots thought they had throttled up to the correct take-off EPR of 2.04, the actual EPR was only 1.70. The aircraft traveled almost ½ mile (800 m) further down the runway than is customary before liftoff was accomplished.

Incidentally, when this accident occurred - I was watching CNN - the B737 hit the 14th Street bridge - there was a TV news team in traffic as the plane hit - the crew jumped out and turned on a live feed onto network tv - which CNN added to their live broadcast.

[square]

You're better off overtorquing the engine than overturning the airplane! The way was taught, it's a poor pilot who crashes because he doesn't have the throttles buried.

[bizjets101]

YouTube explains the accident cause . . .

[BTD]

So as not to hijack the thread, I included one sentence - as opposed to commenting on 100 pages of crash info.

Biz, I appreciate your reply. I think discussion on this is not a hijack on the thread since it is only slightly askew from the original direction of the thread. And I hope a healthy debate can clear things up for others.

Only two Boeing's have had problems regarding icing on takeoff... ...and neither direct cause was the snow on the wings

To my knowledge, there has never been a takeoff crash of a Boeing due to wing ice contamination.

People will cite the 1982 crash in the Potomac as having been caused by wing-ice contamination.

Wing-ice was only a very minor factor in that case.

The above statements are why I join conversations like this. They both state in a factual sense something about a specific accident. Both statements are false according to said accident's report on probable cause.

In 1982 a 737 crashed due in-part to ice on the wings. It also crashed in-part due to a incorrect power setting that resulted from lack of engine anti-ice use. The report states that either would not likely have caused the accident in itself.

both had false air -speed indications

This is also not a correct statement. Your reference to the CVR illustrates that the crew was debating about whether the aircraft was accelerating normally. The airspeed itself, though, was indeed correct. Not false. The airplane was accelerating slowly. Perhaps this is what you meant and simply misspoke.

Maybe I'm alone on this, but when engaged in a discussion/debate about something I like to be as sure as possible about something before I make a statement. Especially when it is so easy to find.

Google: Air Florida 737 crash probable cause.

7th down is a direct link to the NTSB Executive Summary.

Among other things it says

their decision to take off with snow/ice on the airfoil surfaces of the aircraft,

BTD

[QKDH8]

YouTube explains the accident cause . . .

So does this:

http://libraryonline.erau.edu/online-fu ... R82-08.pdf

And it's a much more reliable source. (Official Accident Report)

what I inferred was the airspeed of the Air Florida did not jive with the engine readings, and in the probable cause was listed as; the captain’s failure to reject the takeoff during the early stage when his attention was called to anomalous engine instrument readings.

That might have been your intention, but what you actually said was

Only two Boeing's have had problems regarding icing on takeoff - 6 weeks apart - a Sterling B727 in Gander (no one injured) but aircraft substantially damaged and the Air Florida in Washington - both had false air -speed indications and neither direct cause was the snow on the wings..

The only mystery crash of a large commercial airliner due to wing contamination was the very controversial crash of the Arrow Air in Gander; Click Here. 25 years ago!!!!

That is false. In neither case was "false air-speed indications" listed as a contributing factor or cause for either of those accidents.

To respond to "legoman":

Majority of people have a life and dont spend their free time sifting through hundreds of pages of documentation to know the real facts of a crash. That's about the best answer I could give you.

This is true, but I'd caution those who are to busy to ensure the information they are passing on is correct, perhaps refrain from providing their misinformation, or at the very least preface it with an "I think this was the way it was, but I'm not sure" comment. Doing anything other than that just makes you look bad.