Icing questions?

[SDdriver]

Does anybody know where I can find some really good reading on flying a twin turbine in Icing conditions? I know all of the basics, but I would like to know more about flying in icing conditions from people that are really experienced. I am from the south and we don't get much down here, but this winter I will be fling farther up north and want to get better prepared for what I might encounter. Such as landing on snow covered runways and taking off in icing conditions. The plane I fly is fully certified into known ice with the exception of freezing rain.

Any advice would be appreciated!

SD

 

[Cornelius]

After the ATR indiana crash, a lot of manufacutuers made aircraft specific iciing videos. I know Embraer made one and I think you can order a NASA video from sporty's or something. The NASA video was actually really informative and discusses tail plane stalls and stuff. Look around for videos and books at pilot shops, and I'm sure you'll find plenty of info out there.

 

[flyingtoilet]

NASA Video

The NASA video is excellent. Great because of the actual flightdeck footage during icing upsets. Also, I think it's less than $10.

 

[KingAirer]

Just bought one at Sportys.com a few days ago. Only $5.

 

[RJones]

Re: Icing

Cornelius is correct. When I was flying the Mu-2 we had to watch a video of a Mu-2 flying behind a tanker getting covered with a reddish orange water spray that would ice up the Mu-2. Then we talked about icing conditions and got signed off. The company gave us a certificate/card that said we knew what we where doing and we went back to the job of flying crummy under-powered Mu-2's in icing conditions.

Sporty's Pilot Shop sells a small book by Porter J. Perkins and William J. Rieke called In-Flight Icing. Very good and goes into detail about the different types of icing and what to watch out for.

Good luck, RJ

 

[SDdriver]

Thanks to everyone who responded, I will definitely look into all of that material.

THanks again.

SD

 

[TurboS7]

As nike says. JUST DO IT. I don't recommend anyone staying in icing conditions no matter what kind of airplane they are flying.

 

[JetPilot500]

Here is a couple of high points for you:

1) Blow your boots and blow them often.
Many pilots used to say to blow your boots after about 3/4" of accumulation has built up. That was true of older boots (like those on DC-3's), but the theory was passed down for generations of pilots even though it was no longer necessary to follow that advice. The newer boots can break up smaller amounts of ice with out the concerns of pushing the ice out without breaking it off (bridging). So when you start to see some build up don't be afraid to blow it off too early. If it all doesn't come off, blow them again, it's no big deal.

2) Limit your use of flaps in icing conditions.
Using your flaps increases the exposure of the underside of the wing to the ice. When ice builds under the wing, in unprotected areas, you can create a serious hazard. That ice cannot be removed by boots. I am not saying that you shouldn't use your flaps, just don't put them out prematurely in the ice or especially when holding.

3) Turn the autopilot off if you can.
Many manufacturers now recommend that you hand fly the airplane in icing conditions. That may be a bit of overkill, however they want you to keep the feel of the flight controls to know when a problem may be starting. This was a contributing factor in the AE ATR and Comair Brazilia crashes. However, IMO, if you are single pilot and in a critical phase of flight, use the autopilot.

4) Avoid Freezing Rain!!!
When freezing rain is occuring, the ice doesn't always freeze on impact with the leading edge. Rain may strike the wing and not freeze until it has trailed back on the wing behind the boot. If this occurs, you will be unable to remove this ice on the top and bottom portions of the wing. This will change the aerodynamics of the wing possibly leading to an early or unexpected stall. The best way to notice this type of icing is if you start to see ice streaks forming on the side cockpit windows. GET OUT ASAP!!

5) Don't hang out in the ice.
Icing of moderate or greater intensity usually is only prevelent in 1000 to 3000 foot bands. You can usually get out of this type of icing relatively quickly. If this heavier stuff goes from the surface to 3000', ask for a quick climb or stay a little higher on arrival....ATC will usually help you out. If its around your cruise altitude range, change altitude. You can usually find an area of no ice or only light icing within 2000' of your current altitude.

Icing will not be a problem, if you avoid it as much as possible. Icing conditions can be very unpredictable. Sometimes you will be in a situation totally amazed by the fact that ice is not forming, other times it will be building for reasons also unexpected. Boots do a fine job of keeping you safe if used in the proper situations and if used correctly. Make sure you check them before takeoff when anticipating icing conditions. Also, blow them every once in a while if you haven't used them lately, expecially in the summer.

Good Luck,
JetPilot500

 

[AvLawyer]

I second the recommendation of the book by Perkins and Rieke -- this is a very quick read that can save your life. I had the opportunity to meet Bill Rieke -- he is THE GUY at NASA on icing research, but the book is very practical (rather than scholarly) and contains info that I've never found anywhere else.

Best to you with the Short -- this is an aircraft that **cannot** tolerate heavy ice loads, per a former test pilot I met.


Excellent training videos available from NASA:
http://icebox.grc.nasa.gov/ext/education/video/video.html

Incredible footage of actual icing test flights.

 

[OtterFO]

If everyone here is discussing the same NASA video, it's of a Twin Otter and tailplane iceing. VERY AMAZING footage. They actually get a full tail plane stall condition.

I realize the thread was based on trubine aircraft, but for those operating a piston in ice. I had a friend who managed to bag both vac pumps on a navajo while he was trying to keep up with the ice.... The maintance guru's think he overheated them....

 

[TurboS7]

Keep the power up and fly fast, don't climb fast otherwise you will subject yourself to icing on the lower middle wing or worse yet belly ice. If you are in freeezing rain climb the warm area of weather is just a couple of thousand feet above.

 

[Drifter]

Take a look at your Outside Air Temperature guage while in IMC. From my experience ice really packs on from around the 10 - 25 degree range. I try to avoid flight in that range myself because who needs the weight and the drag. If you have to descend through those temps in the clouds, do it quickly and try not to hang out the gear and flaps at that time if you can avoid it.

 

[mckpickle]

Keep the power up and fly fast, don't climb fast otherwise you will subject yourself to icing on the lower middle wing or worse yet belly ice. If you are in freeezing rain climb the warm area of weather is just a couple of thousand feet above.

Just to clarrify, dont climb at a high deck angle. climb at a higher airspeed if you can. The auto pilot thing is real important. It will hide SO much. You can feel the plane if you dont have the AP on. Flying the ATR is fine in ICE now but you have to be carefull like any other plane. Got into some bad stuff this winter and had about 3 inches on board. The plane will fly but you got to get out of it if its accumulating that quick. And with that quick of accumulation your not going to be able to climb so plan on going down. Also, beware the northeast corner of a front. Usually the worst icing. And watch for a "bridge of ice" This is anyplace that ice builds and looks like a small snowbank. IE unheated portoin of windows, behind boots, window frames ect. Good luck and keep your speed up.

 

[V-1]

JetPilot500 has great advice to offer. I agree with all of it, except I have to qualify one statement. Blowing the boots often is great if you're in a turbine-powered aircraft. If you're in a piston aircraft, be careful about using them too much. The boots usually get their inflation pressure from the vacuum/pressure pumps, whichever the aircraft is equipped with. The impeller vanes in these pumps are made of a fragile material. Heavy, repeated applications of deicing boots will cause premature failure. Hopefully you're in a twin and you have a second one. This isn't a consideration in turbine-powered aircraft.

JP500 has offered the best advice of all - get out of it if at all possible. While some may argue the point, I always tried to climb as high as possible. If I couldn't get out of it, at least I had extra altitude to work with.

If you ever have a mechanic patch a boot, make sure they evacuate any water from the system. Otherwise you'll pull the airplane from the warm hangar, check the boots during run-up and find they work properly. Ten minutes later when you need them they mysteriously won't work. Water in the system will freeze rendering the boots useless.

Flying in Michigan in the winter, the outside air temperature gauge was checked in my scan as often as the airspeed indicator during initial climbs. Information is key to operating successfully in serious icing conditions. Be sure to help everyone else out by passing along pilot reports of cloud tops/icing encounters.

A trick I learned while flying freight up North was to ask the weather briefer what altitudes he/she had wind readouts from doppler radar. Our FSS had radar equipment that could tell the actual winds aloft if there was moisture present. Guess what? If they didn't have any data above say 5000 feet that meant the cloud tops were at or below 5000 feet in the area of the radar site. This trick was extremely accurate at pinpointing the tops of the clouds and showing how layered the weather was.

Watch out for air temperatures between 0 and about -8 degrees Celsius. That's usually when you get the worst icing.

Get high, and stay high as long as possible, unless you noticed a warmer (above freezing) layer lower. Air Traffic Control knows what you're up against and will work with you.

Fly Safely,
V-1

 

[avbug]

Stay out of ice. Ice is bad.

Don't eat yellow snow.

If you're landing on ice, be prepared to take it around, and keep the airplane's long axis strictly in line with the gracker on the ground.

If your're parking on ice after taxiing with skis, block up the skiis. Otherwise, the heat generated from friction will generate enough tomelt the ice, and freeze it into the ground.

Tiedown ropes make good saws for removing snow and accumulations on the tops fo the wings. Always carry a broom or other similiar object for snow removal.

Avoid ice.

 

[SDdriver]

Hey thanks for all the responses, Unfortunantly Avbug I won't be able to stay out of it. I will be forced to fly in it unless, like I said before, it is freezing rain. All of your advice has been great, I do want to know from some people that have done it before, what is landing on a snow covered or icy runway like? I know to use reverse and not brakes and to use differential (SP?) reverse to control your heading, but what is it like? Any advice for that specificly?

Fortunantly I am flying a turbine aircraft with good de-ice equip so that will help I am sure.
I have also heard from most people that the Shorts can haul a big load of ice if needed. It is a really stable platform, but there are a lot of unprotected areas of the aircraft that don't have de-ice boots or hot surfaces.

One last question, if you are flying at say 8000ft and start picking up ice, but the boots are working to break it off, would you climb out of it anyway? Also is the rule to always climb if you are getting ice? I know there could be warmer air below, but flying at the altitudes we do there is not a whole lot of room below to go down. So if it will climb, should you always try to climb out of it?

Thanks again.

SD

 

[avbug]

SD,

If you're getting ice, regardless of your de-ice or anti icing capabilities, do something to get out of it if you can. Climb or descend. If you can't descend to warmer air, then climb to get altitiude to deal with your problem, or to climb out of the icing layer if you are able.

The airplane may be able to handle the present rate of icing. However, you may lose that deice capability. If you're in it at the time, what was once an annoyance or no big deal, may suddenly turn into a really big deal.

The loss of a blanket or boot, or the failure of a bleed valve may nor may not be noticable until the indications of aerodynamic difficulty become manifest. We're all so accustomed to relying on idiot lights and agreement/disagreement lights to tell us that everything is working. If we can't see it on the ammeter or the annunciator panel, it must be okay. However, this isn't always the case, and it's too late to figure that out when in the ice.

Icing can get bad fast. I had an experience in a Twin Commander once that put the fear of God and Ice into me in short order. It involved a rapid ice accumulation that put an inch of ice on in a minute, and caused an initial 50 knot speed loss. In less than a minute and a half we were through blue line and then slower, and descending, and unable to maintain MEA. We were in mountainous terrain in instrument conditions. Ice from the props sounded like a 12 gage being continuously fired behind our ears, and it did significant structural damage to the airplane.

The significant part of that experience was that the aircraft on the route ahead of us didn't get it, nor did the trailing aircraft. We flew through an area which was small geographically, that was pushing some warm, moist, saturated air upslope rapidly. It cooled rapidly, and it occured right where we were. The chief pilot for that operation was in the right seat, and I was flying. I had been present only a short time previously when he had declared to a class of new-hires that the Twin Commander can carry any amount of ice, and only lose 15 knots.

Be really careful when people tell you an airframe can carry a lot of ice, without trouble.

Some years ago I was eastbound in a large four engine airplane. We were picking up some ice, but it didn't seem to be a big deal; the usual 1/4" or trace that we would see in the winter in the clouds. In a short time period, it built such that large 6" horns were sticking off the leading edge and prop spinners, and we began to get a very pronounced aileron "snatch." I immediately descended and notified ATC, and onl 2,000 to 3,000 below the icing layer, we shed most of it.

Had we been unable to descend for whatever reason (we were fortunate enough to be over low, flat terrain), I would have elected to climb. Even if I was unable to get out of the ice, the altitude might buy time in the event of a problem. The point there is that if all the options aren't available, pick the best of what you have left and work with that.

Be cautious of systems failures or issues such as a blown boot, or blown cell. You can have a single cell in a multi cell boot or blanket that fails, and this can cause some ice bridging issues...even in nice, modern equipment.

The FAA has pushed more recently for continuous use of boots at the first sign of icing, and has even published a paper trying to tell us that "ice bridging" is more myth than reality. I disagree strongly, even with more modern boot systems that pulse at higher rates and frequencies, or that operate at higher pressures. Additionally, anybody who has ever popped a boot, only to have the boot pop or burst, comes to realise staying in ice and relying on deice capability is a fools errand.

Icing conditions exist that can take down the most capable of aircraft. Embedded cells or orographic lifting action, or any convective activity or mountain activity, can result in severe ice in very light or mild conditions. I'm sure that many of us have had our scares. We're coming into icing weather again here shortly. At the higher altitudes, it's a year-round issue. It's a good time to begin thinking seriously about ice once more.

Remember that de-ice and anti-ice equipment isn't really for flight into or through known icing conditions. It may be labled that way for certification, but really it's for getting out of ice.

Ice bad. Very bad. Except maybe in a slurpee. The coke ones, not the cherry ones, that leave you looking like you wore closet lipstick or something. Ice bad. Very bad. Snowcones good. Except in the winter when give bad headache and chills. Then ice very bad.

 

[SDdriver]

Thanks AvBug, I just ordered a book and the NASA video on icing. I am going to educate myself thoroughly before this winter, and before I ever get myself into the situation. To all that wrote, thanks for helping out a fellow pilot with all of your advice.

Fly safe and Tailwinds,

SD

 

[Checks]

I almost always climb, you can always go back down.

I also never stay in icing more than 10 seconds because I dont want to get deiced at my destination so I pretend like I dont have any deice equipment.

Someone mentioned temps...0 thru minus 4 is the worst. Tops of clouds are also horrible. The more airspeed you have the better the boots will blow off the ice so sometimes I will descend at a slightly faster rate than normal to get some extra airspeed then blow the boots.

Good Luck

 

[mckpickle]

I understand, sometimes you CANT get out of it. What I watch is the airspeed. If it is decaying more than a few knots every 5-10 minutes you need to execute your escape plan( because you already thought of one). Sometimes you just cant get out and have to deal with it. Keep the auto pilot off and feel for any type of buffet, roll or pitch. My turbo prop just cant climb out sometimes so always remember what alltitude you got ice and what type in case you have to go back down. While climbing might be the best sometimes you pick up SO much in the climb you wont get out.

As far as landing on icy runways.

Ever ride a tricycle on a frozen pond. That can be what its like. Remember, one of the hard parts is breaking out a mins durring a snowstorm. Its like nothing youve seen before. EVERYTHING is white, the ground, sky, runway markings are covered. If your lucky you might see some lights but not much else. Watch the crosswind and fly it until it stops. I mean fly it like an airplane until the airplane comes to a complete stop. Where people get in trouble is when they go from flying to steering the nosewheel. Never turn if you think it would make the plane "lean". Carefull how much reverse you use as it can go from low to NO vis.

Overall very challenging but with the proper respect you will walk away a better and more confident pilot