Comments on: Ice-bridging brouhaha

By: FAA test

FAA test — Thu, 10 Sep 2009 10:43:10 +0000

Regarding ice bridging, I have never seen it.Ice bridging is extremely rare, if it exists at all.

By: Jim Harris

Jim Harris — Tue, 28 Apr 2009 21:38:30 +0000

Ref. Ice Bridging.
Jack Webb indicated (14-Mar-2009) that he had to use 35 pounds of force in a Learjet to overcome melted ice that ran into the aileron gaps.

I experieced a similar situation in a Lear-36, BUT I attributed it to the maintenance department powerwashing the gap seals and dislodging the silicone “grease” on the “Scrub Brush” like material in the gap seal. We duplicated this later at a high altitude that was well below freezing and then went back the same day when the proper “grease” was applied had no problem. (It does get your attention when you think the ailerons are jammed, but we had warm temperatures when descending through the mid-teens.)

By: Andy Reardon

Andy Reardon — Fri, 20 Mar 2009 16:37:29 +0000

Bridging most definitely happens! In the American Bonanza Society Magazine in January, 2005 (might have been 2006. I’m on vacation now and don’t have the copies with me), I published an article regarding my icing experience (one of them) on a flight in a Beech Baron 58 in March 1989 from Cincinnati to Waukegan, Illinois. The flight was terminated at Palwaukee due to closure of Waukegan caused by a corporate aircraft skidding off of the runway at UGN due to ice.
After a missed approach due to low vis at PKE, I landed after a second trip through the 4,000 foot inversion layer. On the second approach,the Baron picked up substantially more ice than on the first approach. I had the boots operating frequently–too frequently. When I landed and Priester Aviation towed me into a hangar, there was ice on the leading edges of the wings and on the outer edges, the boots were covered over, with a large hollow area between the boot and the ice. My only question was how the aircraft still flew with all of the ice, both weight wise and aerodynamic interference. (However, I landed with nearly full power and did NOT TOUCH THE FLAP SETTING after the ice began accreting, consistent with my military instructor’s advice from years earlier.) Another observation: the ice had bridged at about the same distance on both wing leading edges. I could not tell on the stabilizer, though I looked; however, the ice had dropped off of the horizintal stabilizor (but not the wings) by the time I had the opportunity to inspect it. I even tested the boots in the hangar, thinking that perhaps there had been a malfunction. They operated perfectly. Then, after my knees quit knocking, I called my wife for a ride home. Yes, we stopped and had a pop on the way…
Bridging? You bet. Do not ever think that it cannot happen. I know.
By way of background, I am 63, started flying in 1967. Yes, I still fly a Baron 58 ( a different one).
In case one may wonder why I waited from 1989 to 2005 to write the article, it was because I figured that after 16 years, the Fed would not pursue me!
All the best,
Andy Reardon

By: M.Bolski

M.Bolski — Tue, 17 Mar 2009 04:48:06 +0000

My experience is small 1500h. I ferry airplanes across country incl. Alaska, North Atlantic, over Artic circle, Europa and not always have the pleasure of using any de-ice or ant-ice equipment. Well, the FAA jurisdiction don’t go over international water, but it doesn’t mean I would not follow FAA or NASA recommendations. I learn from experience of others fellow pilots (dead and alive), FAA & NTSB statistic, recommendations and so far I’m still alive getting my own-experience flying in very un hospitable environment . I think the subject of Ice-bridging is more in theory than in real life. Yes – if boots are activated to often or to early, they will not clean the edges so good , but this got nothing to the subject. If boots become stuck in inflated!!! position! for too long in a freezing condition, then we can talk about ice-bridging. My personal limits -get out of ice condition ASAP at all cost. Doesn’t make a difference if I’m flying with de- or ant–ice equipment. I think more important is: ice accumulation on high performance wings (C400, Cirrus, Extra 300) vs. old timers (C182, C206) I know for a fact, that C182 with no ice protection, almost 2 in. rim ice and even more on landing gear will fly fine. Cirrus with TKS activated too late! will scare the live out of you with just some ice left on edges and probably a lot on landing gear. There is something call wet wing effect (don’t mistake with TKS) where water contamination (rain only) can increase stall speed. Flying Extra 300 in heave rain on approach close to stall speed and max weight ??? I know people who end up on a wheelchair. With respect to all heave metal pilots with zillion hours, it’s easy to drink coffee at FL300, flying C172 non-stop for 8 hours over North Atlantic with Ice –X blown from leading to trialing edge in unpredicted ice condition— that’s what’s call experience. Coffee guarantee, but in a diapers. Sorry for my English –but it is to me, a second language.

By: Andrew Stryker

Andrew Stryker — Mon, 16 Mar 2009 03:58:19 +0000

Heavy Metal Pro:

Please stick to hauling freight. The idea of the captain of my next flight having an attitude like yours frightens me more than the prospect of getting out on the wing with a ruler to see if that’s 1/8″, 1/4″, or some other arbitrariy thickness of ice out there.

By: Jack Webb

Jack Webb — Sat, 14 Mar 2009 17:56:57 +0000

I have not experienced ice bridging but I have had ice that did not want to release from the boots. Later we discovered, doing icing tunnel tests in Cleveland, that using boots not cleaned and dressed, it took more force tangential to the boot surface to break the ice loose. This probably translates to the ease with which the airstream would help the ice depart the aircraft. Boot dressing is important!
Additionally I had a problem holding in LearJet where the ice melted from the leading edge but flowed back and refroze in the gap between the aileron and the wing. This was nasty and was most probably caused by the low speed for holding of about 190 indicated. It took over 35 pounds of pressure on theh control wheel by both the copilot and me to free the ailerons. There other problems caused by the hold and we told Center we needed immediately another altitude or clearance from the holding pattern. We increased our speed to over 320 knots which eliminated the problem.

By: Paul Buller

Paul Buller — Fri, 13 Mar 2009 19:51:56 +0000

My experience is that it is more a matter of the treatment applied to the boots than exactly when you cycle the boots. Our airplane detailer used to apply a floor wax to the boots of our Turbo Commander to make the boots look shiney. They looked great but the ice would stick like glue to the boots. After some investigation I was told about B.F. Goodrich Icex treatment for their boots. I was told that it looks ugly but it works well. I can verify that statement is true on both counts. The ice would come off completely with just one inflation of the boots. I have always let a little ice build up before activating the boots. That seemed to work fine. As far as waiting until an 1/8 or 1/4 or 3/4 inch builds up all I can say is while flying hard IFR during an approach in the mountains I would find it very difficult to determine the thickness of the ice buildup by looking out the window. I think it is best to cycle the boots when you see ice on them. If you can see the ice it is probably thick enough to break off when you cycle the boots.

By: Gordon Graves

Gordon Graves — Fri, 13 Mar 2009 17:35:03 +0000

Icing makes for an interesting debate. Let me preface what I am about to say with this: I have a great deal of respect for my compatriots at NASA and the FAA. However, experience has taught the effect of political expedience on otherwise impeccable scientific research and/or technical data. I know they have our best interests at heart. But, I have come to question the motives of any government bureaucracy, because I should… For that matter, how do we determine if the change to selecting “Auto”, by itself, will have been effective, when included with the dissemination of other knowledge gained from testing, evaluation, and accident investigation?

So often we hear “after extensive testing”, or “after extensive evaluation”, “it has been determined that…” How extensive is extensive? Could it be that one of the many considerations for this determination was the knowledge that, at the time some accidents forced the issue into the lime-light, the “manual technique” (after a certain amount of accretion) was the most espoused? Certainly science and technology could not produce the urgent fix-all that could assuage the threat of a Congressional hearing, the way a simple change in technique could. Irregardless, due to the insidious nature of ice and the plethora of lawyers and a legal system that favors their litigious aims, we must now add the de-ice switch to “AUTO” to the expanding list of switches that must be selected for optimal affect in court, should an event occur. And, in the event of litigation, that we are told to select “Auto” would, at least, afford the government some relief, if not the pilot or crew. As I said, “I do know they have our best interests at heart”.

Experience is a hard teacher. She gives you the test first, then the answer. We’ve all learned some things from experience. As a fledgling flyer, I had great opportunities to gain knowledge from mentors (Chef Pilots and Captains) who survived some of life’s tests and shared their experience.

During my career spanning 40 years as a professional aviator I have come to know that life is a test. If the test were an FAA test, the correct answer to the question of which to select for de-icing is “Auto”. However, icing is insidious, always leave yourself an out. Fly as though Anti-ice/De-ice equipment will fail; where are you going? Developing this attitude is no different than if an engine fails; where are you going? Just different ingredients for a different soup. I’m sure NASA and the FAA didn’t intend “Auto” to be a fix-all. Neither is it a panacea, even when you are reaching the limits of task saturation, ice doesn’t care! “Manual” is still available and always will be. If “Auto” doesn’t provide the desired result or doesn’t work, switch to “Manual” as often as necessary. Either way, I know of no aircraft certified for flight into heavy or severe icing. For that matter, I have yet to fly an aircraft certified for flight into known icing conditions that the Flight Manual does not recommend leaving the icing environment, as soon as possible, when icing conditions are encountered.

It’s not so much a question of which as it is when. Now that I think about it we had “Anti-ice (De-ice)” inserted at several locations on our (FAA approved) checklist. Interesting how few times the need for anti-ice (de-ice) corresponed with the checklist call-out. Icing is a fact of life. If you’re in it, it should be a part of your scan.

By: heavy metal pro air

heavy metal pro air — Fri, 13 Mar 2009 16:20:50 +0000

NEVER, EVER inflate the boots until u have at least a quarter inch of ice on them@! I have 24,000 hours (how much time do you have Mr. FAA/NASA?) and that is in everything from Cubs, Navajos, biz jets, to 767′s. I flew air taxi in piston twins for years with boots and I can tell u if u inflate boots prior to ice buildup u will die. Are u gonna believe NASA who has to scrap 26% of their shuttle missions and has a horrible safety record (blown up shuttles, fires, etc) or are u gonna believe the “voice of experience”. NASA and the FEDS are totally irresponsible for publishing so called “facts” when they have very little experience in the real world of ice flying freighters 6 nites a week for 30 years like some of us real timers have! By the way, my accident record is flawless, NASA’s is horrible!

By: Jason A

Jason A — Fri, 13 Mar 2009 16:10:28 +0000

Call it what you want, ice bridging or rubber ice, But I can tell you if you don’t allow the ice to build up at least 3/4-1 inch thick on a Merlin, you’ll never get a clean wing. Same goes with 210′s and barons. I think it’s just the inefficiency of boot systems. Boots work fine when operated correctly for your particular airplane. Most I’ve found do require a fairly significant amount of accretion to effectively shed when you pop the boots.

However, we can’t even get the FAA to make up their mind about a definition of “known icing!” Best defense for pilots is when you find yourself in the ice, DO SOMETHING ABOUT IT NOW. Don’t hold and don’t screw around with the stuff. Get out of it as soon as you can. And if you fly a van, leave the plane on the ground PERIOD!