Clean aircraft concept?

I am assuming he's a russian freight dog.

I am not sure how it sounds in Russian but in English the callouts go

80 knots cross check
90 knots contamination check
1xx knots V1
1xx knots rotate
 
dasleben said:
Quite correct, but I have yet to see one where it's permissible for the prop to blow snow/ice off the wing in lieu of deicing.
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Permissibl, no, not legal in U.S. However, all those rules were built around straight wing turboprops without leading edge devices and hot wings. If you can think of one accident of a jet transport with LED's and hot wings that resulted from airframe ice or snow, please enlighten me.
 
dasleben said:
Quite correct, but I have yet to see one where it's permissible for the prop to blow snow/ice off the wing in lieu of deicing.
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It's not in lieu of deicing, it is to verify that falling snow is not adhering to the aircraft. I'm pretty sure I've seen it in a 135 Ops manual if it is not part of the wording of either of the Ops Spec paragraphs Houston posted.
 
seagull said:
Permissible, not legal in U.S. However, all those rules were built around straight wing turboprops without leading edge devices and hot wings. If you can think of one accident of a jet transport with LED's and hot wings that resulted from airframe ice or snow, please enlighten me.
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I know where you're going with this. There hasn't been one. Doesn't mean there couldn't be.
 
dasleben said:
It's Aeroflot.
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Ya I assumed it was a jet, and a passenger was filming in the back that knew something was not quite right.

My comment was based on a freight dog mentality when you know the definition and became a great judge of the concept of of "adhering" as well as "representative surface". While it is not a standard test I would use in a jet and with people on board, I became very good at judging adhering properties of snow in tuboprops filled with freight.
 
seagull said:
Permissibl, no, not legal in U.S. However, all those rules were built around straight wing turboprops without leading edge devices and hot wings. If you can think of one accident of a jet transport with LED's and hot wings that resulted from airframe ice or snow, please enlighten me.
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http://www.ntsb.gov/investigations/fulltext/AAB0603.html
"The Board concludes that the probable cause of this accident was the flight crew's failure to ensure that the airplane’s wings were free of ice or snow contamination that accumulated while the airplane was on the ground, which resulted in an attempted takeoff with upper wing contamination that induced the subsequent stall and collision with the ground. "
http://www.ntsb.gov/aviationquery/brief.aspx?ev_id=20001211X14270&key=1
"THE ICE CONTAMINATION ON THE WINGS RESULTED IN AN AERODYNAMIC STALL AND LOSS OF CONTROL AFTER LIFTOFF. "
http://www.ntsb.gov/aviationquery/brief.aspx?ev_id=20001213X32505&key=1
"The National Transportation Safety Board determines the probable cause(s) of this accident as follows:
ICE/FROST REMOVAL FROM AIRCRAFT..NOT PERFORMED..PILOT IN COMMAND"
http://aviation-safety.net/database/record.php?id=19910217-2
"PROBABLE CAUSE: "The failure of the flight crew to detect and remove ice contamination on the airplane's wings, which was largely a result of a lack of appropriate response by the Federal Aviation Administration, Douglas Aircraft Company, and Ryan International Airlines to the known effect that a minute amount of contamination has on the stall characteristics of the DC-9 series 10 airplane. The ice contamination led to wing stall and loss of control during the attempted takeoff."
http://aviation-safety.net/database/record.php?id=20020104-0
CAUSAL FACTORS: "1. The crew did not ensure that N90AG's wings were clear of frost prior to takeoff.; 2. Reduction of the wing stall angle of attack, due to the surface roughness associated with frost contamination, to below that at which the stall protection system was effective.; 3. Possible impairment of crew performance by the combined effects of a non-prescription drug, jet-lag and fatigue."

http://www.aviationweek.com/aw/gene...&headline=Fine-Grain Icing on Aircraft&next=0
 
TFaudree_ERAU said:
Just for the record, Challenger 600/601/604/605 and CRJ 200 don't have leading edge devices.
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Sorry- I thought by LEDs he was talking about leading edge ant-ice devices rather than leading edge lift devices. DC-9 does. Also this was a quick check of US registered crashes and not foreign registered crashes.
 
Blackhawk said:
Sorry- I thought by LEDs he was talking about leading edge ant-ice devices rather than leading edge lift devices. DC-9 does. Also this was a quick check of US registered crashes and not foreign registered crashes.
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Only the 30 series and beyond. The ones listed did not have LED's.

Keep trying, though. Many people list Air Florida, but, like the SAS accident, that was a power issue.

I don't think you'll find one that was a result of anything but a power problem. FOD (or not pushing power up due to ice on engine pitot probes) has been an issue. Ice on the aerodynamic surfaces, not so much for jet transports with LEDs. During the 60s, 70s in particular, aircraft often did not even get deiced prior to takeoff. The assumption was that it would blow off. All the regulation was a result of straight wing turboprops. We must comply with the regulations, cross the "t"s and dot the "i"s, and make sure you do as the risk of a violation if you do not is very real. It is unfortunate, as the cost and environmental damage from doing too much is staggering. It would be nice to be able to do the research and re-write the reg, but it is not likely to happen.
 
I remember the last time this discussion came up, a year or two ago.

Seagull, do you have any links to any articles about the subject? I don't doubt it at all, rather, I am just curious to know just how leading edge devices can render snow aft of their position on the wing not so harmful.
 
I should point out that there is a possibility that the this Arrow accident was a result of not getting de-iced, but it was far from clear and there were a lot of other issues going on with this one and it is possible it had some unusual ice formations due to ice on arrival. Still, there were so many other issues going on with this flight that it is also possible that the Board just got it wrong (which, in my experience, happens more times than not, unfortunately). Fatigue was clearly a player in Arrow as well.

In answer to your question, there are a variety of issues present that would mitigate the effects with the LEDs, it is an interesting question. I would strongly state getting de-iced is important and we should do it, just that we are likely in an "overkill" mode for it, so comply with the regulation and you don't have to worry about doing more than that in an LED equipped transport jet. Absent LED's, I would be waaay more careful about it, and would take the regulatory guidance as the minimum that should be done, rather than being more than enough.
 
seagull said:
I should point out that there is a possibility that the this Arrow accident was a result of not getting de-iced, but it was far from clear and there were a lot of other issues going on with this one and it is possible it had some unusual ice formations due to ice on arrival. Still, there were so many other issues going on with this flight that it is also possible that the Board just got it wrong (which, in my experience, happens more times than not, unfortunately). Fatigue was clearly a player in Arrow as well.

In answer to your question, there are a variety of issues present that would mitigate the effects with the LEDs, it is an interesting question. I would strongly state getting de-iced is important and we should do it, just that we are likely in an "overkill" mode for it, so comply with the regulation and you don't have to worry about doing more than that in an LED equipped transport jet. Absent LED's, I would be waaay more careful about it, and would take the regulatory guidance as the minimum that should be done, rather than being more than enough.
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I did not include the Air Florida crash or the Gander crash for reasons you listed- I do think it was the cause of the Gander crash but that is disputed. See the link for the 1991 Sweden crash. Slats or no slats would not have made a difference as the shedding snow/ice was ingested into the tail mounted engines.
It is also difficult to tell with most of the Russian/Soviet crashes as they usually don't list a cause. Just "crashed on takeoff" or not even that- just a "?".
 
TFaudree_ERAU said:
Not according to the NTSB:
http://www.ntsb.gov/aviationquery/brief.aspx?ev_id=20020917X01907&key=1
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I know that, but the aircraft would not have flown (and the performance would have been similar) with the same power applied and NO ice at all.

It is important to closely look at the accident boards reports (from any country). They often miss key elements or do not attribute things where they should. This is largely because the entire process is flawed and based on outdated sequential accident models. It is easy to say that it was wing contamination because it is easier to "fix" than many of the other issues that existed. The fact remains that Palm 90 would have flown if they had pushed the power up.
 
I would be interested in seeing research related to this. Until then, this crew was operating as test pilots; Airbus requires all surfaces be clear prior to departure, and this crew departed with a fair amount of wet snow. I don't believe that a lack of accidents is any sort of conclusive evidence that this can be done safely on aircraft with LEDs. How is single-engine performance affected by contaminated surfaces? Are there any adverse handling characteristics specific to that aircraft (aileron flutter, etc.)? These are just two of the many questions that need to be answered before anyone can call this video safe (and I know you're not specifically calling it that, seagull).
 
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