CRB ice detector... worth It?

Discussion in 'Avionics and Upgrades' started by WannFly, May 12, 2017.

  1. WannFly

    WannFly En-Route

    Joined:
    Nov 28, 2016
    Messages:
    4,742
    Location:
    KFAR
    Display Name:

    Display name:
    Priyo
    So, any feedback on carb ice detector? Is it worth it? Seems like a peace of mind to me, but what do u guys think?

    I am aware of the symptoms and the troubleshooting steps if the motor runs rough... try carb heat, if it gets worse and then better, it's carb ice, if not, check mixture, then may. But with a carb ice detector it seems like the first step could be eliminated, assuming it's working.

    Thoughts?

    Sent from my SM-G935V using Tapatalk
     
  2. jordane93

    jordane93 Final Approach

    Joined:
    Sep 9, 2013
    Messages:
    9,442
    Location:
    Long Island, NY
    Display Name:

    Display name:
    Jordan
    We have one of the Archer at my flight school. Even with the sensitivity turned all the way down, it still detects ice. It's pretty much useless on our plane.
     
  3. denverpilot

    denverpilot Tied Down

    Joined:
    Nov 8, 2009
    Messages:
    51,937
    Location:
    Denver, CO
    Display Name:

    Display name:
    DenverPilot
    On what aircraft and powerplant combo?

    The 182 is somewhat known for "making ice" and I wouldn't bother with it on ours. It'll run rough or lose a little power, so you pull on the heat and it coughs and sputters and carries on.

    You'll probably want a Piper driver's opinion on yours but I wouldn't bother with one on ours.
     
    WannFly likes this.
  4. WannFly

    WannFly En-Route

    Joined:
    Nov 28, 2016
    Messages:
    4,742
    Location:
    KFAR
    Display Name:

    Display name:
    Priyo
    Ha. Is it rigged RIGHT? I wouldn't think carb always have ice. But I do understand that it can happen pretty much anytime, especially with low power

    Sent from my SM-G935V using Tapatalk
     
  5. AggieMike88

    AggieMike88 Touchdown! Greaser!

    Joined:
    Jan 13, 2010
    Messages:
    17,980
    Location:
    Denton, TX
    Display Name:

    Display name:
    The original "I don't know it all" of aviation.
    We have an EI electronic carb temp gauge in the 182P that JCranford and I fly in our club. Doubles as an OAT (additional probe). I find it nice to have to caution you that carb ice is possible. But I don't recall it ever being the reason I pulled carb heat outside of the normal routine.
     
    denverpilot and WannFly like this.
  6. Stewartb

    Stewartb Final Approach

    Joined:
    Nov 21, 2014
    Messages:
    6,353
    Location:
    Wasilla, AK
    Display Name:

    Display name:
    stewartb
    When I installed a JPI EDM I added carb temp. Used it for about 30 seconds on the first day. Nada since.
     
    denverpilot and WannFly like this.
  7. WannFly

    WannFly En-Route

    Joined:
    Nov 28, 2016
    Messages:
    4,742
    Location:
    KFAR
    Display Name:

    Display name:
    Priyo
    This might be a Ford - Chevy thing, but the way I understand it, is the CRB probe detects the temp, not actual ice or frost. Or at least that's what the CRB ice detector companies say

    Sent from my SM-G935V using Tapatalk
     
  8. denverpilot

    denverpilot Tied Down

    Joined:
    Nov 8, 2009
    Messages:
    51,937
    Location:
    Denver, CO
    Display Name:

    Display name:
    DenverPilot
    If that's all it is, a temp gauge, it'll come on regularly. Just being at the temp for carb ice doesn't guarantee carb ice.

    As @AggieMike88 said, the Cessna version is just a temp needle with a range that has been painted yellow.

    In the few Cessnas I've been in that had it added as a factory option, it was generally useless because it was always in or moving through that range on every flight.

    If all that silly thing is on Pipers is a light that comes on when the temp is in that range, I'd find it to be more of a distraction than useful.

    Still: The specific airframe and powerplant is important to know. Then you look for folks who fly those and ask them whether they make ice.

    The 182 *does* tend to, but it's something you just learn to recognize through poor performance. MP doesn't look right for the altitude, rough running, what feel like little engine misses... you pull the heat on and it melts immediately and the engine coughs on a blob of water going through it.

    Let's put it this way. Over 300, pushing 350 hours in that single 182, and I've had to pull the carb heat on other than just doing it for normal landing procedure, three times. Granted, I'm flying in the dry high plains too, but folks will tell you the carb'd O-470 will make mountains of carb ice. Never really seen it, even when flying at wetter and denser air locales outside of weather so muggy you don't even want to be flying.

    And that kinda weather would be where @AggieMike88 lives and he's also saying a known
    "Icemaker" airplane doesn't do it there either.

    So... I'd go look for stories of when yours makes ice and then just be aware of engine power. Tons and tons of aircraft don't have these.

    Maui will be along shortly to tell you to invest in an AoA instead. Hahahaha.
     
  9. ircphoenix

    ircphoenix En-Route

    Joined:
    Feb 29, 2016
    Messages:
    2,690
    Location:
    Redondo Beach, CA
    Display Name:

    Display name:
    ircphoenix
    From my reading, the O-320 configuration in the Cherokee is not known for making ice. In fact, the only direction to use it during flight is "as necessary." Precautionary use during low power operations isn't required.

    I'd bet the carb is at icing temps pretty regularly, so having an indicator that ice making temperature is present doesn't seem terribly useful. That being said, if I get an engine monitor in my plane, I'll probably add a carb temp probe.

    Carb ice detector, however, sounds gimmicky as all get out.
     
    WannFly likes this.
  10. jordane93

    jordane93 Final Approach

    Joined:
    Sep 9, 2013
    Messages:
    9,442
    Location:
    Long Island, NY
    Display Name:

    Display name:
    Jordan
    There's probably something wrong with it.
     
  11. GRG55

    GRG55 Final Approach

    Joined:
    Dec 29, 2015
    Messages:
    7,524
    Display Name:

    Display name:
    Aztec Flyer
    :yeahthat:

    With the notation that (I believe) the OP has an O-360 in his Cherokee. Neither engine has a reputation for carb icing. I've owned Cherokees with both those engines and that was my experience.

    To the OP, there's lots of other things I would spend my airplane upgrade money on before resorting to a carb temperature gauge in a Cherokee.
     
    ircphoenix and WannFly like this.
  12. AggieMike88

    AggieMike88 Touchdown! Greaser!

    Joined:
    Jan 13, 2010
    Messages:
    17,980
    Location:
    Denton, TX
    Display Name:

    Display name:
    The original "I don't know it all" of aviation.
    We just get a steady yellow light. But as you said... it's more an advisory that carb ice could form, not that it will or has.
     
  13. WannFly

    WannFly En-Route

    Joined:
    Nov 28, 2016
    Messages:
    4,742
    Location:
    KFAR
    Display Name:

    Display name:
    Priyo
    QUOTE="denverpilot, post: 2290378, member: 6717"]If that's all it is, a temp gauge, it'll come on regularly. Just being at the temp for carb ice doesn't guarantee carb ice.


    Thanks, I will post in the piper forum and see what some 181 guys have to say. too bad for our Hawaiian friend.. but I already got one .... :p
     
  14. WannFly

    WannFly En-Route

    Joined:
    Nov 28, 2016
    Messages:
    4,742
    Location:
    KFAR
    Display Name:

    Display name:
    Priyo
    yepp. its a 360. thanks guys
     
  15. denverpilot

    denverpilot Tied Down

    Joined:
    Nov 8, 2009
    Messages:
    51,937
    Location:
    Denver, CO
    Display Name:

    Display name:
    DenverPilot
    Ahh. Sounds like an aftermarket on in your bird, then. That or it's a restart thing. What year is yours? The original from Cessna as an option on our 1975 is just a temp gauge.
     
  16. Timbeck2

    Timbeck2 Final Approach

    Joined:
    Nov 4, 2015
    Messages:
    7,002
    Location:
    Vail, Arizona
    Display Name:

    Display name:
    Timbeck2
    I have this on my Cherokee. If gives me peace of mind if I'm flying into potential icing conditions. If nothing else the OAT is easier to read than that stupid unicorn temperature gauge installed on my windshield.

    [​IMG]
     
    WannFly likes this.
  17. James331

    James331 Ejection Handle Pulled

    Joined:
    Apr 18, 2014
    Messages:
    20,311
    Display Name:

    Display name:
    James331
    Every carbed plane I've flown had a ice "detector", first the thing runs ruff, then I pull the heat, and runs worse, then better.

    If you're looking to spend money lots of better places
     
    WannFly likes this.
  18. simtech

    simtech En-Route

    Joined:
    Aug 15, 2012
    Messages:
    2,737
    Location:
    mississippi
    Display Name:

    Display name:
    Simtech
    In a cherokee/archer...I personally wouldn't spend my money on one. Our planes are not known to make ice much. That's why in the poh you will notice it never directs you to use it unless you suspect it. Unlike a Cessna. Like others have said, I'd spend my money on something else. Unless you get a Jpi that has it as part of it but I wouldn't spend the money for a stand alone carb ice gauge.
     
    WannFly likes this.
  19. AggieMike88

    AggieMike88 Touchdown! Greaser!

    Joined:
    Jan 13, 2010
    Messages:
    17,980
    Location:
    Denton, TX
    Display Name:

    Display name:
    The original "I don't know it all" of aviation.
    It's the one that Timbeck2 pictured.
     
  20. Witmo

    Witmo Pattern Altitude

    Joined:
    Feb 19, 2006
    Messages:
    2,085
    Display Name:

    Display name:
    Tim
    There are some carb ice detectors that have an optical probe in the throat of the carb that will "see" ice forming. We had them on the aeroclub planes in Korea. Theoretically, they're a wonderful idea but in practice the autogas we were using in Korea was fouling the lens of the probe and they were always indicating ice. How they would work if we used avgas, I don't know.

    I put in the cheapest carb temp gauge in my C-150 (whose 0-200 could have been made by Frigidaire and marketed as an icemaker) and it was of some limited utility during warm days when you naturally don't think about icing and yet the carb temp is right down there where icing is possible. During the winter it was pretty much useless as the temp was always down where icing could be a problem.
     
    WannFly likes this.
  21. NealRomeoGolf

    NealRomeoGolf Pattern Altitude

    Joined:
    Apr 12, 2016
    Messages:
    1,649
    Location:
    Illinois / Germany
    Display Name:

    Display name:
    NRG
    I have carb temp on my 181 through my CGR-30P. Don't look at it a ton, but I do watch the numbers move when I pull my carb heat. At least tells me it's working.

    This actually isn't true. Your carb temp goes up when you pull power out. If I follow the physics right, less fuel running through the carb so the pressure drop is less which means the temp drop is less. I think I got that right. :dunno: Seemed weird to me too, but as I pull power out for the descent, I can watch my carb temp rise on my CGR.
     
    WannFly likes this.
  22. JohnAJohnson

    JohnAJohnson Cleared for Takeoff

    Joined:
    Aug 14, 2006
    Messages:
    1,242
    Location:
    Gulf Shores, AL
    Display Name:

    Display name:
    JohnAJohnson
    Yea, me too. But on my runup, when I pull carb heat I get to watch the temp go up100 degrees or so :)
     
  23. MajorTurbulence

    MajorTurbulence Pre-takeoff checklist

    Joined:
    Jan 9, 2013
    Messages:
    202
    Display Name:

    Display name:
    MajorTurbulence
    I have gotten carb ice several times in my Archer, and mostly, but not exclusively in low power situations. I'm always leary of it when practicing approaches, and certainly when the humidity is up. I thought of adding the carb temp probe to my EI Ubg-16, but other add ons were more pressing. I just use my carb heat for a few seconds whenever I think of it, and before landing for a few moments when going through the landing checklist and in long descents. I think it's a good discipline to get used to.
     
  24. NebC

    NebC Filing Flight Plan

    Joined:
    Aug 7, 2019
    Messages:
    1
    Display Name:

    Display name:
    BCrunner
    If anyone is interested, I have a brand new never installed ARP Carb Ice Detector. It’s the remote mount version. Comes with everything. Planned to install it and then sold plane. I like these a lot more than the carb temp probes. Will take $350 shipped to domestic USA address.
     
  25. benyflyguy

    benyflyguy Pattern Altitude

    Joined:
    Jan 1, 2018
    Messages:
    2,483
    Location:
    NEPA
    Display Name:

    Display name:
    benyflyguy
    I have a 182H with a 0-470 and I pull the heat a lot. Live in NEPA and I’d like to think we have a lot of icing potential. Problem with ice is you can never prove it when someone augers in like dry tanks leave evidence. The proof melts away. If I have any reduced power setting I pull it. Even on those hot humid days. I will hear the engine make like a miss sound. Pull it. I think my mixture runs a bit rich though too. So sometimes at reduced power setting humid on approach I’ll hear that engine miss sound. Too rich?? Ice??
    I don’t know what if there is any danger in using the heat more often. Thoughts?
     
    Sinistar likes this.
  26. Dan Thomas

    Dan Thomas Final Approach

    Joined:
    Jun 16, 2008
    Messages:
    6,132
    Display Name:

    Display name:
    Dan Thomas
    Your physics could kill you. As you close the throttle, the fuel flow less, alright, but the pressure drop, instead of being at the venturi near the temp probe, moves to the edges of the throttle plate as it closes, and that drop gets really big. A big pressure drop means a big temperature drop. Boyle's Law. Both evaporative cooling and temp drop due to pressure drop are in play here. At low power settings, not idle, the two work together to drop the air temperature more than 70°F. And that's why the carb ice charts reflect that.

    [​IMG]
     
  27. flyingbrit

    flyingbrit Pre-takeoff checklist

    Joined:
    Apr 21, 2014
    Messages:
    232
    Display Name:

    Display name:
    flyingbrit
    Dan, you seem to be one of the more knowledgeable posters here so perhaps you can explain something on the carb ice chart that has always bothered me: Why are pressure carbs susceptible to icing at 80% RH but not 100%?
     
  28. Sinistar

    Sinistar En-Route

    Joined:
    Sep 9, 2016
    Messages:
    2,640
    Display Name:

    Display name:
    Brad
    For the reduced power during approaches in hot humid summer our 182 also rumbles/pops a bit but only with full carb heat. It is just running rich. During my PPL training on a lazy summer night at a Delta airport my CFI was wondering about this. We were cleared to land as we entered downwind. Per the POH I had pulled carb heat prior to entering the pattern. To experiment the CFI was able to pull the mixture knob out over 1.5" before it just started to stumble. Just prior to the stumble point it was running crazy smooth. Of course he had crap tons of time in 182 and 206, could land anything and all 3 runways were open and we were cleared on one of them. It is just running rich.

    The other lesson is to not shove in the carb heat and then shove in the throttle quickly afterwards (like a go around). Either bring them in together or push in full throttle and remove the carb heat. I did the opposite on a touch and go and it sputtered and I aborted the takeoff.

    IMHO The carb inlet temp gauge is absolutely useless, at least on the carb'd 182's As @denverpilot already mentioned its in the damn yellow zone almost all the time. It is a good confirmation that its working if you pull carb heat but you can also hear it and see it in the MP. If there was an actual ice detector with a flashing light I'd be interested. If you are getting a engine monitor probably might as well get it but once again not sure how useful it would be. If a Carb Ice detector and Carb Ice temperature sensor+gauge were the same $$$$ I'd get the detector first.
     
  29. Tantalum

    Tantalum Final Approach

    Joined:
    Feb 22, 2017
    Messages:
    5,266
    Display Name:

    Display name:
    San_Diego_Pilot
    The newer Archer at the club has one. The POH manual is pretty vague as far as setting it, I typically turn it on when reaching cruise altitude (cruise power set, carb heat off), I turn the knob just high enough to extinguish the "carb ice" light and leave it there. Seems to work okay enough. Two observations
    -when I enter any kind of IMC the light illuminates. Engine sounds fine, but it's obviously picking up a chance, so I fire on the carb heat. There's no real risk at altitude of using it
    -when I power down it starts to illuminate.. if I am VMC, no visible moisture, and engine sounds fine and it's warm out I'll generally leave the carb heat off and just turn up the knob a bit

    Interesting, ours does not, see above
     
  30. WannFly

    WannFly En-Route

    Joined:
    Nov 28, 2016
    Messages:
    4,742
    Location:
    KFAR
    Display Name:

    Display name:
    Priyo
    since i have put in the JPI 830 with a carb temp gauge..during a slow decent i set JPI to display the carb temp, if it stays about 40 degrees, i dont bother with carb heat unless there is visible moisture
     
  31. benyflyguy

    benyflyguy Pattern Altitude

    Joined:
    Jan 1, 2018
    Messages:
    2,483
    Location:
    NEPA
    Display Name:

    Display name:
    benyflyguy
    I did the same thing on a t&g once and it sputtered and thankfully we were on the ground. Probably flooded it.
    I was told to really watch for MP drop that’s unexplained. Once at altitude I lock the MP and then if I see it start to move a needlewidth I apply the heat.
     
    Sinistar likes this.
  32. Dan Thomas

    Dan Thomas Final Approach

    Joined:
    Jun 16, 2008
    Messages:
    6,132
    Display Name:

    Display name:
    Dan Thomas
    Never worked on one. They're pretty rare. But I could imagine that there's a spot in the throttle plate's travel where impact icing is possible. The venturi at the carb's air inlet causes a small pressure drop that could cause condensation of water vapor that could be supercooled water once past the venturi, and hit that partly-closed throttle plate and stick to it. Closing the plate further (reducing power) would reduce the venturi's pressure drop, and opening the throttle all the way (100 percent power) would minimize the plate's profile to the airflow. That's all speculation, and maybe someone else around here has some more experienced input.

    Pressure carb looks like this:
    1519429380682.jpg

    Note that the fuel is injected downstream of the throttle plate, nowhere near it or the venturi, so any icing due to evaporative cooling would happen in the induction manifolding.

    The venturi is there only to generate a vacuum signal, and a dynamic pressure signal is also generated by the impact tube nxt to the inlet. Both are used to meter the fuel. It's similar to the RSA (old Bendix) aircraft fuel injection systems, but the fuel is squirted into the airflow at the carb instead of into the intake ports at the cylinders.