Carb Ice, It Can Happen Quickly

Flying my 1954 Piper Supercub over Illinois it develops carburetor ice. Carburetor Ice can be a problem when there is high humidity, as often happens in the summer. It is not necessary for the air temperature to be freezing to develop carb ice. Indeed it most likely occurs when the air is warmer than freezing. Lots of moisture is necessary for it to form. This video shows the rapid development of carb ice after takeoff and the RPM drop associated with application of carb heat and the change in the quality of the exhaust due to the water. So sit back and enjoy "Carb Ice"

[TheAirplaneDriver]

Just happened to me yesterday. I was doing lazy 8’s in my 1947 Cessna 140. Power was reduced to 2300 rpm and because I was loading and unloading the engine as I was climbing and descending in the procedure, I didn’t notice a reduction in power as the ice built up. Sure enough, after a few minutes the engine started running rough as hell...just like in your video. I immediately switched tanks, applied full carb heat, and gradually increased power. While doing all that, I simultaneously turned back towards an airport that was about 3 miles behind me and as I still had power, climbed so I was sure to have enough altitude to get there. I was about 1, 500’ AGL when it happened.

It took about a minute (seemed like an eternity) before the engine cleared. All other instruments checked fine.

After things settled out, I checked the temps off a nearby airport with ATIS which were 41degrees with a 27 degree dew point on the ground. OAT at altitude was a bit lower....about 38 degrees but I’ll bet the dew point was the same at altitude as on the ground making things worse. That put me solid into the serious icing range.

I was certain it was carb ice but to be sure nothing else was wrong I landed and checked the engine compartment to make sure there were no other obvious problems. I then did a couple of takeoff and landings with full power run ups (rpm’s good) then went on my way home.

I’ve got 9 years and 1, 000 hours in my plane and that was the first time that happened to me! What a surprise!

[SL]

Thanks for posting this. It's nice to see a real-life example of what it carb ice sounds like and how to deal with it. MUCH better than a book

[GAG]

In all my years flying small planes I never had any problems with carb ice...thank goodness! Very interesting and informative video, I don't remember hearing about adding carb heat slowly, I might have just forgotten, old age catches up with all of us eventually. Very nicely done video as well, love all the camera views on the plane.

[lee]

Id just like to say how much I enjoyed your video. Excellent quality. Was really surprised on how quickly the icing started to build up.

[brandonvillalobos]

Great video! Thanks for the explanation, as to why apply carb heat slowly.

[markoda]

Excellent video.  Loved the camera mounts and the information that I gain was great.   As a student pilot I wouldn't have thought about icing with nice blue skies and temps in the 60's.  Thanks for sharing.

[BiggieTSkinny]

Thanks for the video and the link to the pdf! Your video footage is superb! I think this further enforces my desire to fly an R model 172 over a carb. N model. Although our club always keeps the tanks at 53 gallons limiting useful load. Great video sir.

[AlcidesSegovia]

Great video man. Glad your ok! I like your youtube channel. look forward to more

[SKYGUY]

Very nice video. Thanks.
I took off from Wise VA once in a 172 for a photo flight and about a mile from the end of the runway at full power the aircraft suddenly started shaking very badly. I applied carb heat (full), turned back to toward the airport, and announced the situation. It strated to smooth out and I hovered around the airport for a minute or two and decieded to continue the flight w/ carb heat on all the time. There were big fluffy clouds all around. It came on suddenly though and I though I had lost a prop tip it shook so hard... nothing like the smoothly reduced power m instructor demonstrated to me. Be prepared for anything. Terry, CFI-I

[halcyon]

Thanks for posting. Currently studying for VFR - this really helped me understand the process.

[itzajdmting]

Fantastic footage - well edited. I saw how wet your tyres were and surmised it was probably morning and there'd be quite a bit of moisture hanging in the air. Great video.

Nice to see somebody using lots of exterior views, it was a real pleasure. Sick of the "look at me I'm a pilot" vids!

[slaznum]

Great video and use case for carb heat, very enjoyable

[grummansteve]

Smart for checking Carb Icing probability chart before flight! I always do as well. Also, as a technique, prior to take-off I line up on the runway and set about 1200 RPM, and apply carb heat for about 30 seconds when the chart predicts a high probability of icing. I have had my carb ice up more than once when taxiing for departure. My AA1 does not glide well, and you have many more options than I do at your home airport if the engine runs into problems on takeoff. Beautiful scenery as well that you get to see!

[LibertyLakeWildlife]

Great message. Have had carb ice occur in my old -182 before reaching 500 feet where I power back on climb out. POH states "apply carb heat with any visible moisture including rain, drizzle, virga, or fog." They are not kidding as it happens very fast as your video demonstrates well.

[noahg]

I like the technique! Regarding not having options to land: You had a million fields to land in; Especially flying a Super Cub with tundra tires in Illinois!

[ianturner]

Very well spotted Sir, many plots would have panicked and let the engine stop rather than thinking about the likelyhood of icing on what appeared to be a wonderful morning for flying a Cub.  Very useful training video for any flying school, should be mandatory viewing.

[massimomelodia]

Temp. 60F, DP 58F : carb ice is just around the corner... Thanks for sharing.

[Cubonaut]

Thanks Michael - I appreciate the comment.  I wondered why they changed my antenna when I changed my comm to a Trig unit - that's probably why!  It does work better now.

[AvgDude]

I fly a 150 with an engine monitor that has carb temp. If the carb temp goes below freezing, I’ll start partial carb heating after I get to 1000’ AGL after takeoff, even at max power on climb out. I always do full carb heat on descent when below 70F. Yesterday I flew while it was freezing out and kept partial to full carb heat to 35 or more degrees the entirety of my flight. Never an issue. Even with reduced power on climbs, the cold weather gives 500’/min. easy.

[WATERS]

Just had some pretty scary carb ice today, I have 140 hours total time (private VFR) and was doing some basic practice work with my CFI. I kinda wanted to see how O had progressed since my check ride. I was very happy with the results, steep turns which used to be kind of a chore were fun and precise slow flight was easy because I really understood what it was that I was doing etc.. Anyway the RPMs were of course low for the air work that I was doing and the engine started to run rough in the Cessna 150, I thought to myself"couldn't be the legendary carb ice, that I have heard so much about ". Sure enough my CFI said I think we have carb ice (just as I was thinking it) I put on the heat and it got rough and then smoothed out. I thought it would be a lot smoother as far as the drop in RPMs and the sound, it is defiantly a rougher sound then I expected. I can also definitely see were slow application of the Carb hea as opposed to sudden would be a good idea but check with a CFI on that.