When to use pitot heat ?

[John Citizen]

When are you supposed to use pitot/static heat ? or when do others use it ?

- always in IMC ?
- always. including day VMC ?
- always at night ?
- icing conditons only (your definition of it is) ?
- always above freezing level (including VMC) ?
- anytime in visible moisture (rain/cloud), even with high outside temperature (ie 25 C) ?
- anytime in visible mositure in temperatures below about +10C ?

I am interested to hear other people's thoughts.

Thanks.

[EngineOut]

I use it in visible moisture below 10 deg C below 10000ft, generally speaking always on above 10K, and on in heavy rain at any temperature.

That is just when I use it. My opinion as requested. Before other start telling me I'm wrong, as tends to happen on these forums.

[Massey058]

In both our Cherokee's and Senecas Pitot heat is seleceted on once takeoff clearance has been received on IFR flights

[flyby_kiwi]

Once lined\lining up. Stays on until taxiing clear of rwy after flight. Same too with strobes, mode C etc etc.

[Capt Claret]

Turned on in after start scans. And turned off in after landing scans.

In my whole flying career (20+ years) I've not expereinced a pitot heater failure.

I have however experienced iced up pitots as an F/O flying into cloud in a twin transport category tubo prop because the captain in his infinite wisdom didn't want to turn the heat on so as to prolong the life of said heater. Needless to say, when we flew into cloud at night, the heaters weren't on and the airspeed readings were, shall we say, erratic! :uhoh:

[flying ginge]

I'm with engine out. +10C and below with vis moisture present. Then I watch the turkey timer on the cockpit window to see if it's accumulating ice. Usually the first indicator for me.

[DVDA]

On line up clearance with strobes etc. Any earlier and ours get to hot.turn em off in after landing scan.

[EngineOut]

Capt Claret,

I don't know if I'm unlucky, but I have had 2 pitot heat failures, both worked during pre-flight, and broke sometime between when i next turned it on and when they was full of ice and airspeed (indicated) was decaying quite rapidly(an alarming site).

Luckily this particular aircraft had to pitot systems and 2 ASI, so I used the co-pilot's side for the remainder of the flight. The other one was in an older [read normal GA age] piston twin. This one didn't have 2 ASI's, so just had to use standard rates of descent and normal descent power settings to get back down below freezing safely. Not much fun.

Basically in turbo-props I have flown, as soon as you hit IMC, eyes flick to OAT gauge, if less than 10, all engine/prop anti-ice goes on, and pitot heat (that is just my method). Then you just keep an eye on the wings until you need to make the leading edge go bumpy to get rid of that ice!

[Howard Hughes]

I'm with Kiwi, from line up to vacating. I must say though that this is mandated in the POH of my aircraft.

Cheers, HH.

:ok:

[v1rotate]

On the Fokker F27:

Pitot Heat goes on during the After Start checks and off after landing during the scan. We've never had a pitot burn out during taxi even at Paris CDG with a 40 minute taxi and temperatures of 15 plus.

[clear to land]

From more than one manufacturers manual 'in visible moisture with OAT<10C. Having said that, most turbine aircraft I have flown have been 'ON' in After Start and 'OFF' in shutdown scans. Cheers:O

[psycho joe]

I agree entirely with the <10 deg AND vis moisture line of thought. Having said that I believe that pitot heat is anti-ice and not an anti rain/cloud device. I've flown in some pretty nasty down poors in northern Oz, PNG, Solomons etc and have never seen a pitot blocked by rain let alone cloud. Lastly I think leaving heat on when it's not necessary is just plain lazy.

[TheOddOne]

On some light a/c I've flown, I've seen up to 7 deg compass swing with pitot heat on/off. I believe compasses are swung with all services on, including pitot heat. Thus, even on a warm day VMC flight, I select pitot heat on to ensure compass is within card readings, THEN align DI with it as a part of the vital actions before t/o. This ensures minimum time on the ground with heat on, but aligned DI and compass within limits. Then, final cross-check of DI, compass and runway QDM once lined up and before rolling. This only takes a few seconds but all this drill was how I was taught it for the IMC rating years ago.

Standing by for more disagreement!!
The Odd One

[Capt Claret]

psycho

Perhaps you should write to Messers Boeing, Airbus, deHavilland, BAe et al, and tell them their procedures are "just plain lazy" ;)

[psycho joe]

Claret,

I most humbly apologise for not mentioning every specific aircraft type, nor every operational scenario however I was trying give an opinion without excessively pontificating.

Certainly when you line up in your McNorthrop Grummen Douglas you'll turn on a host of anti-ice protection.

The topic is Pitot/Static heat and is representive of a real conundrum at the GA end of the spectrum. I've seen quite a few pilots turn on pitot/static heat in an un-pressurised aircraft as a matter of routine and oblivious to the fact that they were in the tropics on a stinking ISA +50 day.

Quite a few pilots could be forgiven for thinking that pitot heat is there for rain/ cloud protection. Why else would light aircraft manufacturers put pitot/static heat in an aircraft that has no other anti-ice device? (eg Qiute a few singles and light twins).

My opinion is that in a nill icing cond aircraft, the pitot/ static heat is there to provide acurate ASI Whilst negotiating out of an inadvertant icing situation. em tasol

[Capt Claret]

psycho

Where do you go for an ISA +50 day? What aircraft are certified to ISA +50?

Finally, please note: ;), repeated for clarrification, ;) ;) ;) ;) ;)

[psycho joe]

DEF'N: ISA +50 (colloquialism)

1. Hot, damn hot, f#%king bastard of a place hot.

2. A normal day in the Kimberley.