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Aviation Forum / General / Aviation / July 2009Wing De-Icing Question
Hello, I guess de-icing is going to be a popular subject. Question, please: On commercial jet airliners like, e.g., a 767 or 757, is there any in-flight deicing system for the wing and tail surfaces, other than a leading edge pneumatic boot ? What about the "main," large upper surfaces ? How in general is wing de-icing accomplished on these new, modern jets ? Thanks, Bob > Hello, > [quoted text clipped - 7 lines] > > How in general is wing de-icing accomplished on these new, modern jets ? Hot bypass air from the engines is what they use, in general. I have to admit I do not know it the 787 is going to go truly all electric, or still use hot engine air to heat the wings. Once you get up to airliners of a larger size, the use of boots is not common. In smaller turbine commuters, and in piston planes, (especially pistons) there is not enough heat produced to heat wings.  SignatureJim in NC >> Hello, >> [quoted text clipped - 16 lines] > common. In smaller turbine commuters, and in piston planes, > (especially pistons) there is not enough heat produced to heat wings. yes, there is. there have been many pistons with hot wings, fjukkwit. Bertie > Hello, > [quoted text clipped - 10 lines] > Thanks, > Bob Jets don't typically have boots. Most use hot air stollen from the engines to heat the leading edges. Some use a "leak" system to drip anti-freeze like solution on the tail surfaces to avoid having to plumb the hot air to the rear, although this is less common. I'm not sure that I woudl call the type of plane that crashed less modern than a 767 considering by-pass jet engines (the type in a 767) have been around longer than turbo prop engines that were involed in this recent crash. -Robert > > Hello, > [quoted text clipped - 21 lines] > > -Robert The more I hear about this, the more it sounds like tailplane icing. Take a look at http://video.google.com/videoplay?docid=2238323060735779946 for a NASA produced video on the subject. Note that this flight started its plunge right at or after the outer marker. The outer marker is where you normally lower gear and flaps. Lowering flaps is the thing that causes the tailplane stall if the tailplane is iced up. K l e i n >> > Hello, >> [quoted text clipped - 37 lines] > Lowering flaps is the thing that causes the tailplane stall if the > tailplane is iced up. Rubbish. Bertie > >> > Hello, > [quoted text clipped - 43 lines] > > - Show quoted text - The NASA study on tail stall notwithstanding? >> K l e i n <kle...@aol.com> wrote >> innews:2d099c70-cb73-40be-a62e-feb3015f5 [quoted text clipped - 52 lines] > > The NASA study on tail stall notwithstanding? Well, OK not impossible, but Wing if anythng.. Bertie >The NASA study on tail stall notwithstanding? In this case I think Gezellig is right. After the high-profile Roselawn (ATR) accident a few years ago, and the Vickers Viscount accidents dating back to 1954, we have had ample time to improve our icing awareness, particularly for the most vulnerable aircraft/mission profiles, and if the truth be known we don't have much to show for it . . . > In article <451afb9c-1885-4dc0-bde2-29ed269d4...@q30g2000vbn.googlegroups.com>, > jawnwil...@hotmail.com says... [quoted text clipped - 6 lines] > icing awareness, particularly for the most vulnerable aircraft/mission > profiles, and if the truth be known we don't have much to show for it . . . Umm...I was questioning Bertie....Gezellig's post was down thread. Attribution, attribution....... >> In article <451afb9c-1885-4dc0-bde2-29ed269d4...@q30g2000vbn.googlegroups.com>, >> jawnwil...@hotmail.com says... [quoted text clipped - 9 lines] >Umm...I was questioning Bertie....Gezellig's post was down thread. >Attribution, attribution....... Sorry - I dont receive "Bertie" or "Mxsmanic" or any responses to these self-styled, self-sufficient spammers. The filters I have developed leave me in ignorant bliss with regard to these intellectually impoverished ignoramuses. Don't know how your's got through. If you are involved in discussion with same, frequency change is approved - go away. > In article <62cc83cf-252c-4b4d-b508-28ee8601a...@u1g2000vbb.googlegroups.com>, > jawnwil...@hotmail.com says... [quoted text clipped - 23 lines] > Don't know how your's got through. If you are involved in discussion with > same, frequency change is approved - go away. I don't indulge with Bertie much either but in this thread I was curious about what his reaction to a previous poster hence my question to him. I didn't realize I needed your permission to do that . I haven't seen your 'nym on here much in the past, and that's been without benefit of filters.....just lucky, I guess. >I don't indulge with Bertie much either but in this thread I was >curious about what his reaction to a previous poster hence my question >to him. I didn't realize I needed your permission to do that . I >haven't seen your 'nym on here much in the past, and that's been >without benefit of filters.....just lucky, I guess. OK I apologize. I admit I'm a bit peeved about what some self-indulgent guys have done to normal exchange and discourse here. . . > In article <34723ca5-fa16-4329-bfc5-3475231ac...@s36g2000vbp.googlegroups.com>, > jawnwil...@hotmail.com says... [quoted text clipped - 6 lines] > > OK I apologize. Roger that........ . >>> In article > <451afb9c-1885-4dc0-bde2-29ed269d4...@q30g2000vbn.googlegroups.com>, [quoted text clipped - 18 lines] > Don't know how your's got through. If you are involved in discussion with > same, frequency change is approved - go away. Yessir and that means you fukk up and post AssClown reponses to the wrong peoples. AssClown. SignatureAustin Whitten, President; Geeks-In-Route, Inc; 3808 Gunn Hwy Ste C Tampa, FL 33618 866-661-GEEK Ext 701 813-480-0103 Mobile 813-388-4902 Fax www.geeks-in-route.com On Feb 17, 12:43 am, Austin "The Geeker" Whitten ©¿©¬ <aus...@geeks- in-route.com> wrote: > Yessir and that means you fukk up and post AssClown reponses to the > wrong peoples. [quoted text clipped - 4 lines] > 3808 Gunn Hwy Ste C Tampa, FL 33618 866-661-GEEK Ext 701 > 813-480-0103 Mobile 813-388-4902 Faxwww.geeks-in-route.com Such a sterling contribution..............not. > In article > <62cc83cf-252c-4b4d-b508-28ee8601ae23@u1g2000vbb.googlegroups.com>, [quoted text clipped - 23 lines] > these self-styled, self-sufficient spammers. The filters I have > developed leave me in ignorant bliss Ah, ignorant blss, how nice for you. Bertie > In article > <451afb9c-1885-4dc0-bde2-29ed269d4dab@q30g2000vbn.googlegroups.com>, [quoted text clipped - 3 lines] > > In this case I think Gezellig is right. And, it appears, you were both wrong... Bertie >> Note that this flight started its plunge right at or after the outer >> marker. The outer marker is where you normally lower gear and flaps. >> Lowering flaps is the thing that causes the tailplane stall if the >> tailplane is iced up. > > Rubbish. Uhh, which part of this is rubbish? As I recall from a news account of the FDR, the loss of control was immediately following gear / flap extension. If it was the "outer marker is where you normally lower gear and flaps", well yeah but I'm not sure that's the point. T Tman <no.email@no.email.com> wrote in news:Eq- dnf1SZYzMBwXUnZ2dnUVZ_jMAAAAA@giganews.com: >>> Note that this flight started its plunge right at or after the outer >>> marker. The outer marker is where you normally lower gear and flaps. [quoted text clipped - 9 lines] > If it was the "outer marker is where you normally lower gear and flaps", > well yeah but I'm not sure that's the point. Doesn't mean the tail stalled, In any case, it's the premature assumptions that piss me off, right or wrong. Bertie > Hello, > [quoted text clipped - 8 lines] > How in general is wing de-icing accomplished on these new, modern jets > ? on flight, generally, not at all. On most jets, only the wings and engines have anti or de-icing and it's accomplished by bleeding hot air out of the compressor section of the engines. The engine anti ice is used frequently, but wing de icing is seldom used simply because ice seldom forms on the wings in flight. There is no deicing for the tops of the wings in jets. Bertie > Hello, > [quoted text clipped - 10 lines] > Thanks, > Bob There's a very good chance the Boston crash might have been tailplane icing. DH >> Hello, >> [quoted text clipped - 14 lines] > icing. > DH To explain the erratic flight behavior? > >> Hello, > [quoted text clipped - 16 lines] > > To explain the erratic flight behavior? It's just a guess, but yes. I viewed a NASA film only this morning on this issue. The key if correct would be that whatever happened happened immediately after they went to 15 degrees of flaps. That would have increased the aoa on the tail surface leading edge. That leading edge is sharper than the wing leading edge and very susceptible to icing. Assuming the boundary layer sep point was moving aft on the stabilizer already, when they lowered the flaps they could have easily exceeded the CLmax for the tail. Even if this theory is correct, I'd be looking for additional factors related to icing coupling to cause the autorotation they seemed to have entered prior to impact. It's all theory anyway. The NTSB will come up with something as they progress with the investigation. DH > > >> Hello, > [quoted text clipped - 31 lines] > progress with the investigation. > DH Maybe a silly notion/question buuuut...if this (pitching/roll -this from new reports as of 2/16) had occurred at a higher altitude, 7000 ft say, would the plane have entered a 'flat' spin? Was the impact indicative of such? On Feb 15, 4:23 pm, Dudley Henriques <dhenriq...@rcn.com> wrote: Cool! Let's speculate on speculation. On Feb 16, 8:01 am, the.sar...@gmail.com wrote: > > > >> Hello, > [quoted text clipped - 36 lines] > ft say, would the plane have entered a 'flat' spin? Was the impact > indicative of such? Difficult to say. I'm far from being the expert on transport aircraft. My understanding is that if, and that is still a big IF, tailplane icing was involved in the Buffalo accident, it was the lowering of the flaps and the cfg change to the wing increasing the aoa on the tail that was the factor actually taking them into stall. If that was the cause, the actual breaking of the stall caused by the ice on various leading edges could very well have taken them into uncontrolled auto rotation. For that to happen, yaw had to be present at the stall. The scenario above assumes low altitude due to the flap extension factor. At this stage in any accident investigation, it's always conjecture. Already however, the seldom discussed issue of tailplane icing is getting a lot of attention throughout the entire aviation community and that alone is good for flight safety. The NTSB investigation will provide the answer I'm sure. Dudley Henriques >>>> Hello, >> [quoted text clipped - 31 lines] > progress with the investigation. > DH Following the theory, for the sake of discussion, is this pilot error and is it avoidable? I realize they can't see the tail but icing on the windshield was reported. I have icing, weather, an aircraft with a history of tail icing (due to its design)....even if they had no stick inputs, do you go to flaps knowing that you could possibly cause a sever pitch down and the inevitable results? >>>>> Hello, >>> [quoted text clipped - 42 lines] > knowing that you could possibly cause a sever pitch down and the > inevitable results? NTSB: Flight 3407 Was On Autopilot Before Accident Mon, 16 Feb '09 Practice Violated Company Policy For Icing Conditions A National Transportation Safety Board official confirmed Sunday that downed Continental Express flight 3407 was being flown on autopilot at the time of the crash, contrary to normal procedures. In conjuction with FAA recommendations, NTSB spokesman Steve Chealander said Colgan Air, the plane's operator, recommends that pilots manually fly during all conditions... and requires them to do so when there's evidence of severe icing. "You may be able in a manual mode to sense something sooner than the autopilot can sense it," Chealander told the Associated Press, emphasizing the need to hand-fly the airplane to better feel how it's really flying when conditions are critical. An autopilot will trim out an aircraft, within its capabilities, to compensate for changing conditions -- including airflow disturbances caused by icing -- without the flight crew necessarily becoming aware of any abnormalities. > >>>> Hello, > [quoted text clipped - 42 lines] > knowing that you could possibly cause a sever pitch down and the > inevitable results? Now they're looking at the pilot's possibly having the autopilot on during the descent into and during the icing conditions, against company policy. Anyone who has flown an autopilot will know that it isn't the smartest beast and can cause problems. See http://www.google.com/hostednews/ap/article/ALeqM5hpSZzqkNMwZvX2xrejSSUOyBGCYgD9 6CNPN81 Dan > Now they're looking at the pilot's possibly having the > autopilot on during the descent into and during the icing conditions, [quoted text clipped - 3 lines] > > Dan "The Dash 8 Q400 plane, operated by Colgan Air, was equipped with a "stick shaker" and "stick pusher" mechanism that rattles the yoke to warn the pilot if the plane is about to lose aerodynamic lift, a condition called a stall. If not corrected in time, the mechanism automatically pushes the stick forward to avert a stall. Chealander said the plane was on autopilot until the "stick shaker" and "stick pusher" kicked in, automatically putting the plane back in the pilot's hands. At some point, the pilot switched on an anti-stall device that increases the speed of the plane by 20 knots and gives a pilot more margin to recover from a stall if it occurs. Asked whether the pilot might have overreacted by pulling the stick back when it automatically went forward, Chealander said, "Yes, it's possible." ========================================================================= Isn't this counter to pulling back on the yoke, cutting power and speed, when you get nose pitch due to tail icing? This discussion is rapidly running in the wrong direction. While I do not share the admonition of some that it is "taboo" to speculate about causes of an airplane accident before all of the factual information is in, it is certainly unhelpful and disrespectful to start crying "pilot error" and lamenting all of the things they should or should not have done, before any of the salient facts of the scenario are in place. Similarly, it is reckless to start decrying insufficiencies in any of the aircraft's systems or their use without a solid factual basis for these assumptions. It may be useful to discuss airframe icing and tailplane icing, and it is perhaps pertinent to speculate about its role in the current case, but to go much further can only foster misunderstanding and misinformation. Have instead some respect for the people who lost their lives, and for their families, as well as for the flight crew who just may have known a thing or two about how to fly their airplane. . . > This discussion is rapidly running in the wrong direction. > While I do not share the admonition of some that it is "taboo" to speculate [quoted text clipped - 11 lines] > well as for the flight crew who just may have known a thing or two about how to > fly their airplane. . . Keep in mind that this is a pilot's discussion group. Some of us fly in conditions similar to that in existence for the Buffalo crash. As with all such events, there are things to be learned. I subscribe to "learn from your mistakes, but it's better to learn from the mistakes of others because you won't live long enough to make all the mistakes yourself." As each new bit of information about this event comes available, I try to imagine myself in the same situation and try to figure out what was going on. I had previously been shown the NASA video on tailplane icing while attending a Flight Safety Inc recurrent training course for the Citation. Previously, I'd never heard of this before. Hearing some of the preliminary information about the Buffalo event reminded me of this video so I found it on-line and watched it again and I'm glad I did because I was remembering some of it incorrectly. Anyway, more recent information is a bit inconsistent with the "tailplane icing" theory, namely, that the flight data recorder says that both the stick shaker and stick pusher were activated. This are activated (at least in the Citation) by angle of attack sensors which are electrically anti-iced. I can't see how this could happen in the tailplane ice induced stall scenario. The information about excessive bank angle would also be inconsistent with this, except that if it really were tailplane stall due to ice, the yoke might have been yanked forward and out of the hands of the pilot. Attempting to pull it back might have resulted in inadvertent aileron deflection, causing the roll. K l e i n > This discussion is rapidly running in the wrong direction. certainly unhelpful ... disrespectful ... reckless ... foster misunderstanding and misinformation Yeah I don't really disagree, but egads, this is Usenet and for that sake r.a.p. The epitome of inconsequential. Who cares what's said here? >> This discussion is rapidly running in the wrong direction. >certainly unhelpful ... disrespectful ... reckless ... foster >misunderstanding and misinformation > >Yeah I don't really disagree, but egads, this is Usenet and for that >sake r.a.p. The epitome of inconsequential. Who cares what's said here? Well, a family member may care. What if someone, desperate for information after losing a loved one, starts hunting around usenet and finds a bunch of pilots saying that autopilots are dangerous and their use is negligent? There is a huge human cost in tragedy like this, and we shouldn't forget it. As pilots, we accept the risk involved, but we must be sensitive to the situation of general public who are not expected to accept this risk. Besides that, just as a matter of intellectual honesty, we should give the crew enough benefit of the doubt not to fall to the "it wouldn't have happened to me. . ." fallacy - at least until all of the ifactual information is in? I fly IFR by hand in IMC for practice and recurrent training, but would not subject trusting passengers to this risk. Instead I use the autopilot, whose judicious use I consider to be one of the most important safety devices in the airplane. To say the autopilot should not be used under certain circumstances is one thing, but here we are coming close to the Fox News ideal of posthumously condemning the pilot to 50 counts of first degree for having used the autopilot. > In article <oPadneYjQZsIKwTUnZ2dnUVZ_o2dn...@giganews.com>, > no.em...@no.email.com says... [quoted text clipped - 27 lines] > News ideal of posthumously condemning the pilot to 50 counts of first > degree for having used the autopilot. Interesting, in that we tend to handfly the Mooney in IMC, using autopilot only when we need a break if there's only one pilot on board. It's a subjective thing I suppose, but hand flying does not take a lot of effort en route (or most of the time, if truth be told) and I'd not want to have to suddenly transition to hand flying in IMC in the unlikely event the autopilot had a subtle failure. >Interesting, in that we tend to handfly the Mooney in IMC, using >autopilot only when we need a break if there's only one pilot on >board. It's a subjective thing I suppose, but hand flying does not >take a lot of effort en route (or most of the time, if truth be told) >and I'd not want to have to suddenly transition to hand flying in IMC >in the unlikely event the autopilot had a subtle failure. Interesting. I do not share your point of view, but I respect it. I not only hand-fly, in training, but I (like others) fly partial panel, to simulate vacuum failure (conventional systems) or electrical failure (glass systems). In "real" flight, I use everything available, freeing up the xx% of my brain that was used just maintaining heading and altitude to maintain a higher-level vision of the progress of the flight. I believe this overall vision is more important that the difficulty of transitioning to a degraded control mode in the case of a system failure, partly because of the unlikelihood of the latter. > In article <a623a718-ba75-44ae-8ee7-1b15a6700...@t13g2000yqc.googlegroups.com>, > papp...@gmail.com says... [quoted text clipped - 15 lines] > control mode in the case of a system failure, partly because of the > unlikelihood of the latter. There's more to our side of the story -- we like to hand fly! Our self adminstered safety flights are a bit more challenging than those administered by our cfi, esp w/r/t partial panel, instrument failures, and unusual attitudes. I suspect the difference in safety between our two methods would be hard to quantify. One of us could type more loudly than the other, I suppose -- this is the usernet after all. . >> In article <a623a718-ba75-44ae-8ee7-1b15a6700...@t13g2000yqc.googlegroups.com>, >> papp...@gmail.com says... [quoted text clipped - 23 lines] >type more loudly than the other, I suppose -- this is the usernet >after all. . >> In article <a623a718-ba75-44ae-8ee7-1b15a6700...@t13g2000yqc.googlegroups.com>, >> papp...@gmail.com says... [quoted text clipped - 23 lines] >type more loudly than the other, I suppose -- this is the usernet >after all. . Sorry for the /null/ post!! I like to hand fly too. Insisted on it in my IR training. NDB approaches IMC as well. But I won't subject my passengers to increased risk just because I think it's more challenging for myself. IS THAT CLEAR? I*S T*H*A*T C*L*E*A*R*?? :-) > Sorry for the /null/ post!! Onlyh an AssClown.......... > I like to hand fly too. Hand fly or hand job, AssClown? > Insisted on it in my IR training. NDB approaches IMC as > well. But I won't subject my passengers to increased risk just because I think > it's more challenging for myself. IS THAT CLEAR? I*S T*H*A*T C*L*E*A*R*?? :-) Crystal. Are youh an AssClown? A*S*S*C*L*O*W*N* ? Do I sh.t in the woods? SignatureBear Bottoms Private Attorney General > Besides that, just as a matter of intellectual honesty, we should give the > crew enough benefit of the doubt not to fall to the "it wouldn't have > happened to me. . ." fallacy - at least until all of the ifactual > information is in? I fly IFR by hand in IMC for practice and recurrent training, but would not > subject trusting passengers to this risk. Instead I use the autopilot, > whose judicious use I consider to be one of the most important safety [quoted text clipped - 3 lines] > News ideal of posthumously condemning the pilot to 50 counts of first > degree for having used the autopilot. While I agree with your basic premise, (of not blaming the pilot before the report is out) it is fact that they were still on auto, they knew there was ice, it was against company policy to do so in ice, and it is a generally accepted "fact" that flying on auto in ice can be very risky, indeed. It seems only truthful to say that the pilots did something that was wrong, and in this case, they bought the farm because of it. SignatureJim in NC >It seems only truthful to say that the pilots did something that was wrong, >and in this case, they bought the farm because of it. You may end up being right, but today we simply do not have the factual base to substantiate that claim. The autopilot today is so integrated into normal flight operations that simply "turning it off" would require out of the ordinary conditions, which have yet to be demonstrated for the flight in question. What you claim to be "only truthful" to me is as yet unsubstantiated. >>> This discussion is rapidly running in the wrong direction. >>certainly unhelpful ... disrespectful ... reckless ... foster [quoted text clipped - 7 lines] > hunting around usenet and finds a bunch of pilots saying that autopilots > are dangerous and their use is negligent? f.ck 'em. Hey, AssClown, which part of "discussion" did you not understand? Why not start your own Usenet gruppe and talk to yourself. AssClown to AssClown,, come in..... SignatureBear Bottoms Private Attorney General > This discussion is rapidly running in the wrong direction. > While I do not share the admonition of some that it is "taboo" to speculate [quoted text clipped - 11 lines] > well as for the flight crew who just may have known a thing or two about how to > fly their airplane. . . Explain to me how much more clearly I could state (especially in a discussion group): "Following the theory, for the sake of discussion, is this pilot error and is it avoidable?" >Explain to me how much more clearly I could state (especially in a >discussion group): > >"Following the theory, for the sake of discussion, is this pilot error >and is it avoidable?" Clear as a bell, but in my opinion misguided and unconstructive. Sorry to be so harsh about it, but do you really wish to establish "pilot error" and determine "whether it's avoidable" before a single piece of salient fact is laid on the table? Have you really no respect whatsoever for the factual portion of the investigation? Your impatience to conclude will automatically lead to erroneous conclusions. . . >>Explain to me how much more clearly I could state (especially in a >>discussion group): [quoted text clipped - 8 lines] > factual portion of the investigation? Your impatience to conclude will > automatically lead to erroneous conclusions. . . Grab a reading comprehension manual. Sheesh............ > This discussion is rapidly running in the wrong direction. Try cupping your balls when you stroke your wiener, AssClown. > It may be useful to discuss airframe icing and tailplane icing, and it is > perhaps pertinent to speculate about its role in the current case, Good then STFU. AssClown. SignatureBear Bottoms Private Attorney General > >>>> Hello, > [quoted text clipped - 42 lines] > knowing that you could possibly cause a sever pitch down and the > inevitable results? I would be hesitant to comment to that level not being current in type or directly involved in the investigation. As the investigation progresses there will be a deep look into the aircraft configuration during the descent vs recommended procedures for conditions I'm sure. -DH > There's a very good chance the Boston crash might have been tailplane > icing. Did you mean BUF or did I miss something in Boston? T > > There's a very good chance the Boston crash might have been tailplane > > icing. > > Did you mean BUF or did I miss something in Boston? > T Yes. I've been dealing with a Boston issue most of the day and my senior moment quota kicked in. It was Buffalo. DH In article <49df58d7-733a-487b-9f88-7c4c6b5c13ff@v13g2000yqm.googlegroups.com>, dhenriques@rcn.com says... >> > There's a very good chance the Boston crash might have been tailplane >> > icing. [quoted text clipped - 5 lines] >senior moment quota kicked in. It was Buffalo. >DH Oh thanks! Spent two hours on the NTSB database trying to figure what Boston crash we were talking about! :-) Hello, Not a Physicist, so please bear with me. The posts here seem to imply that wing icing occurs (mainly), if not exclusively, on the leading edges, and not on the upper or lower wing surfaces. Why ? If it does occur on the upper surfaces in modern jet commercial aircraft, is there also hot bleed air available for this large surface, as there is for the leading edges ? If it does occur on modern turboprops, on the upper surface, there is nothing they can do to remove it. Right ? Why did they say that a 180 degree turn "may" help break off ice ? Thanks, Bob --------------------------------- > In article > <49df58d7-733a-487b-9f88-7c4c6b5c13ff@v13g2000yqm.googlegroups.com>, [quoted text clipped - 12 lines] > Oh thanks! Spent two hours on the NTSB database trying to figure what > Boston crash we were talking about! :-) > Hello, > [quoted text clipped - 39 lines] > > - Show quoted text - Think for a moment about the airflow around thle wing. At one point the air flows up and over, and a little lower on the leading edge if flows down and under. There is a line then, the point where the flow seperates, where there is little airflow at all. It's called the stagnation point. If ice is going to form it will form where there's not a lot of wind blowing the water away, that's why it forms on the leading edges. You'll see, in icing conditions, ugly ice sticking out from the leading edges first. The magic of a 180 degree turn is, back where you came from there was not ice forming -- go back there! > The magic of a 180 degree turn is, back where you came from there was > not ice forming -- go back there! ?????????? > > The magic of a 180 degree turn is, back where you came from there was > > not ice forming -- go back there! > > ?????????? I may not have been clear. If you find yourself in icing conditions, retreating (do a 180) is often a good option. >>> The magic of a 180 degree turn is, back where you came from there was >>> not ice forming -- go back there! [quoted text clipped - 3 lines] > I may not have been clear. If you find yourself in icing conditions, > retreating (do a 180) is often a good option. Thx! >Hello, > [quoted text clipped - 14 lines] >nothing they can do to remove it. >Right ? Not quite. Good points though. The "hot wing" solution used on high-flyers is to heat the leading edges so hot that freezing particles will not only remain above freezing, but simply vaporize to avoid run-back re-freezing. Yes, that means very hot, and lots of energy to burn. The turboprop and high-performance piston solution is to use de-icing boots that inflate to break off ice after it has formed. There is ongoing debate about "ice bridging" the theory that the boots may inflate too soon, and that ice will form around or over the inflated profile so as to render the boot cycling ineffective. "Official" and "user" opinions vary as often as the seasons change on this one. Not to be neglected is the "TKS" system, more popular on high-performance pistons than on turboprops, which weeps de-icing fluid across the wings through millions (yes, millions) of micro-pores drilled in the leading edges. Popular in Mooneys for years, it is gradually gaining ground and may actually find application in passenger tirboprops in years to come. . . There's a significant weight penalty for that de-icing fluid, and when it's gone, it's gone. . . > In article > <49df58d7-733a-487b-9f88-7c4c6b5c1...@v13g2000yqm.googlegroups.com>, [quoted text clipped - 12 lines] > Oh thanks! Spent two hours on the NTSB database trying to figure what > Boston crash we were talking about! :-) Sorry. Those "senior moments" can be annoying for sure. It's a shame youth is wasted on such young people. :-))) -D >> In article >> <49df58d7-733a-487b-9f88-7c4c6b5c1...@v13g2000yqm.googlegroups.com>, [quoted text clipped - 17 lines] >:-))) >-D No harm done. We always learn something by going back through the NTSB records! I was surprised to find how few accident records included both the location "Boston" and the keyword "icing". Aside the FEDEX takeoff incident, where ice caused physical damage to one of the engines, I learned that a Skymaster crashed in 1975 departing Boston, probably because of airframe icing. His intended destination? Buffalo :-) > In article <44321efd-b322-40b7-b48d-a8b71b39e...@z1g2000yqn.googlegroups.com>, > dhenriq...@rcn.com says... [quoted text clipped - 27 lines] > Skymaster crashed in 1975 departing Boston, probably because of airframe > icing. His intended destination? Buffalo :-) I belong to a world-wide flight safety work group that uses the base all the time. It can be useful as you say. Our work is primarily involved with the low altitude aerobatic display environment but many in our community are airline people and have a great interest in anything that enhances the learning curve safety wise. I was pleasantly surprised to discover that in our work group alone, the interest in tailplane icing has increased since yesterday to the point where information has been spreading throughout the low to medium altitude turbo-prop scheduled and non- scheduled operations world wide. -DH > I belong to a world-wide flight safety work group that uses the base > all the time. It can be useful as you say. Our work is primarily [quoted text clipped - 7 lines] > world wide. > -DH There's something radically wrong here. Of course the horz stabil can ice, a tail can ice. Of course there should be a sh**load of info on it but I'll be damned if I know where it is. POH? Cessna 15x or 17x? Diamonds? > > I belong to a world-wide flight safety work group that uses the base > > all the time. It can be useful as you say. Our work is primarily [quoted text clipped - 12 lines] > but I'll be damned if I know where it is. POH? Cessna 15x or 17x? > Diamonds? You're right. There should be much more written on the issue. NASA has been working on it for quite a while now and in fact has done a film piece on it for distribution throughout the aviation community. Just in case you haven't seen the NASA piece, I've included a link on it for you. It's worth watching! http://video.google.com/videoplay?docid=2238323060735779946 -DH >>> I belong to a world-wide flight safety work group that uses the base >>> all the time. It can be useful as you say. Our work is primarily [quoted text clipped - 21 lines] > > -DH Like another poster, first time I had ever seen this and it is a great piece. Should be std fare for PPLs imo, at least for turboprop multis. > >>> I belong to a world-wide flight safety work group that uses the base > >>> all the time. It can be useful as you say. Our work is primarily [quoted text clipped - 24 lines] > Like another poster, first time I had ever seen this and it is a great > piece. Should be std fare for PPLs imo, at least for turboprop multis. I sent it out internationally through our pipeline this morning. It's being distributed as we speak. -DH In article <5ce52bc4-6f80-4f81-802a-dee4be16d346 @h20g2000yqn.googlegroups.com>, dhenriques@rcn.com says... > > > I belong to a world-wide flight safety work group that uses the base > > > all the time. It can be useful as you say. Our work is primarily [quoted text clipped - 19 lines] > it for you. It's worth watching! > http://video.google.com/videoplay?docid=2238323060735779946 A very good video, I have emailed it to some Air New Zealand folk, and hope they distribute it around. SignatureDuncan > In article <5ce52bc4-6f80-4f81-802a-dee4be16d346 > @h20g2000yqn.googlegroups.com>, dhenriq...@rcn.com says... [quoted text clipped - 28 lines] > -- > Duncan Flight safety works in many mysterious ways sometimes. An accident always causes discussion and movement in the community. The speculation of course is seldom useful and can actually be detrimental in certain cases, but the exposure and subsequent distribution of flight safety issues like tailplane icing that don't get much press every day can be a VERY positive factor in increasing awareness of these issues. Spreading the word is always helpful. -DH On Feb 17, 3:03 am, VOR-DME <Vor...@terps.org> wrote: > In article <ae48ed29-23ce-41af-8d00-676091b77...@x38g2000yqj.googlegroups.com>, > papp...@gmail.com says... [quoted text clipped - 38 lines] > > - Show quoted text - As I suggested, I doubt very much we put ourselves or our px at increased risk by hand flying. The NTSB in fact in this case is on record as suggesting hand flying is better than autopilot. You are intitled to your opinion, but your attempt to type loudly is less than mature. Given that, I would not choose to fly with you as PIC. You can probably post in a larger font, that might help you 'shout' better. |
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