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24V Heated Pitot

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jdubner(at)yahoo.com
Guest

Posted: Sat Oct 03, 2009 6:52 pm Post subject: 24V Heated Pitot

I have a chromed AN 5812-1 14V heated pitot tube from Aero Instrument 

Co. and need the exact equivalent in a 12V model.  Anyone care to trade?



Anticipating some responses that lead to thread drift: I don't want to 

change the heating element.  And yes, it gets hot on 12V but not hot 

enough to suit me.  I rather just swap with someone who has a 12V model 

and a 24V airplane.



Thanks,

Joe

Independence, OR

http://www.mail2600.com/position

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nuckolls.bob(at)aeroelect
Guest

Posted: Sun Oct 04, 2009 11:13 am Post subject: 24V Heated Pitot

At 09:46 PM 10/3/2009, you wrote:

  	  Quote: 	
		  I have a chromed AN 5812-1 14V heated pitot tube from Aero Instrument Co. and need the exact equivalent in a 12V model.  Anyone care to trade?



 Anticipating some responses that lead to thread drift: I don't want to change the heating element. 	


    It's physically impossible to retrofit these devices. The

    heating elements are stainless tubes about 12-15" long

    with spiral wound segments tailored to deliver specific

    amounts of heat to various portions of the tube assembly.



 [img]cid:.0[/img]



 Here you can see the heater tube as it loops twice through

 the labyrinth chamber and around the nose piece. I had to

 cut the tube apart just to SEE the heater . . . replacing

 it as a maintenance operation is not an option.



  	  Quote: 	
		    And yes, it gets hot on 12V but not hot enough to suit me.  I rather just swap with someone who has a 12V model and a 24V airplane. 	




   What defines "hot enough to suit"? Know that the 

   crafting of a practical heated pitot tube involves

   a careful study of ice accretion characteristics

   under worst case conditions. The goal is to prevent

   liquid ice (super-cooled water droplets) from becoming

   solid ice on contact . . . this requires MUCH more energy

   than that required to maintain the surface at above

   freezing temperatures. As I alluded earlier, it's also

   not a function of simply installing a heater  . . . the

   heater is a long, linear, un-even liberator of heat

   crafted to the task.



   Here's some data I took on an identical pitot tube in

   flight (clear air). 



  http://www.aeroelectric.com/Pictures/Curves/Pitot_tube_temps_at_altitude.pdf 



   The upper curve shows that while RAT was sometimes

   below -35C, the pitot tube was over 100C in cruising

   flight at 41K feet. An THIS was on a tube that was

   being studied for potentially deficient ability to

   avoid freezing under some conditions.



   Heated pitot tubes have been installed on tens of

   thousands of light aircraft not certified for flight

   into know icing conditions. I wouldn't discourage

   anyone from adding this feature to their airplane . . .

   it just MIGHT save your bacon one day. But know

   too that the icing conditions that would render your

   airspeed (and perhaps static instruments) useless

   are similarly destructive of the airplane's ability

   to fly.  But then, it might be interesting to know

   how high you are and how fast you're going down . . .



 

        Bob . . .



         ---------------------------------------

        ( . . .  a long habit of not thinking   )

        ( a thing wrong, gives it a superficial )

        ( appearance of being right . . .       )

        (                                       )

        (                  -Thomas Paine 1776-  )

         ---------------------------------------

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cjensen(at)dts9000.com
Guest

Posted: Sun Oct 04, 2009 12:54 pm Post subject: 24V Heated Pitot

Joe,



As Bob said:

"The goal is to prevent liquid ice (super-cooled water droplets) from becoming solid ice on contact . . . this requires MUCH more energy than that required to maintain the surface at above freezing temperatures. As I alluded earlier, it's also not a function of simply installing a heater  . . . the heater is a long, linear, un-even liberator of heat crafted to the task."



 	  Quote: 	
		  From a qualitative perspective, it takes very little pitot heat to keep the pitot clear of rime and clear icing that we occassionally bump into at the altitudes that most GA flies.  If we accidently run into SCD icing, we'll likely have far bigger and faster problems, long before the pitot heating is overcome by the super-cooled droplets.  But, as always, each should do that that gives the greatest level of comfort.

 
	


Chuck



--

rmitch1(at)hughes.net
Guest

Posted: Sun Oct 04, 2009 7:31 pm Post subject: 24V Heated Pitot

On the data plate it says 24V?  You didn't really mean 14V?

Bob Mitchell

L-320



--

jdubner(at)yahoo.com
Guest

Posted: Sun Oct 04, 2009 9:51 pm Post subject: 24V Heated Pitot

In spite of my best efforts to avoid thread drift ...

All I want to do is have a reliable source of dynamic pressure at all 

times.  It's not a secret but neither is it well known: the Dynon EFIS 

requires a working pitot system for reliable attitude information. 

*Attitude*.  Not just airspeed.  I don't want to turn an inadvertent 

icing encounter into an emergency (and I consider flying 

needle-ball-and-airspeed with failed airspeed in IMC an emergency).

I'm 100% positive an AN 5812 12V heated pitot operating with a 12V 

electrical system will provide enough heat in an RV at RV altitudes and 

airspeeds.  I'm not sure a 24V heater running on 12V will.  It might, 

but I won't be performing a "careful study of ice accretion 

characteristics under worst case conditions".  I just want to swap this 

24V model with someone (perhaps a Lancair builder?) who could use it and 

has an equivalent 12V model lying around.

We both agree: I'm not going to be changing the heating element 

Anyone want to trade?

--

Joe

Robert L. Nuckolls, III wrote:

 	  Quote: 	
		   At 09:46 PM 10/3/2009, you wrote:

> I have a chromed AN 5812-1 14V heated pitot tube from Aero Instrument 

> Co. and need the exact equivalent in a 12V model.  Anyone care to trade?

>

> Anticipating some responses that lead to thread drift: I don't want to 

> change the heating element.

    It's physically impossible to retrofit these devices. The

    heating elements are stainless tubes about 12-15" long

    with spiral wound segments tailored to deliver specific

    amounts of heat to various portions of the tube assembly.

 Emacs!

 Here you can see the heater tube as it loops twice through

 the labyrinth chamber and around the nose piece. I had to

 cut the tube apart just to SEE the heater . . . replacing

 it as a maintenance operation is not an option.

>   And yes, it gets hot on 12V but not hot enough to suit me.  I rather 

> just swap with someone who has a 12V model and a 24V airplane.

   What defines "hot enough to suit"? Know that the

   crafting of a practical heated pitot tube involves

   a careful study of ice accretion characteristics

   under worst case conditions. The goal is to prevent

   liquid ice (super-cooled water droplets) from becoming

   solid ice on contact . . . this requires MUCH more energy

   than that required to maintain the surface at above

   freezing temperatures. As I alluded earlier, it's also

   not a function of simply installing a heater  . . . the

   heater is a long, linear, un-even liberator of heat

   crafted to the task.

   Here's some data I took on an identical pitot tube in

   flight (clear air).

 http://www.aeroelectric.com/Pictures/Curves/Pitot_tube_temps_at_altitude.pdf 

   The upper curve shows that while RAT was sometimes

   below -35C, the pitot tube was over 100C in cruising

   flight at 41K feet. An THIS was on a tube that was

   being studied for potentially deficient ability to

   avoid freezing under some conditions.

   Heated pitot tubes have been installed on tens of

   thousands of light aircraft not certified for flight

   into know icing conditions. I wouldn't discourage

   anyone from adding this feature to their airplane . . .

   it just MIGHT save your bacon one day. But know

   too that the icing conditions that would render your

   airspeed (and perhaps static instruments) useless

   are similarly destructive of the airplane's ability

   to fly.  But then, it might be interesting to know

   how high you are and how fast you're going down . . .

        Bob . . .

         ---------------------------------------

        ( . . .  a long habit of not thinking   )

        ( a thing wrong, gives it a superficial )

        ( appearance of being right . . .       )

        (                                       )

        (                  -Thomas Paine 1776-  )

         ---------------------------------------

glastar(at)gmx.net
Guest

Posted: Sun Oct 04, 2009 10:13 pm Post subject: 24V Heated Pitot

Joe, get yourself the newest 5.1.1 version of the software and hook up a 

GPS that will give you additional comfort as with that version the 

attitude is, in case of dyn. press. lost backed up with GPS speed. 

(Interesting to see on takeoff roll when a message tells you that before 

the pitot comes live.



Werner

 	  Quote: 	
		  

 All I want to do is have a reliable source of dynamic pressure at all 

 times.  It's not a secret but neither is it well known: the Dynon EFIS 

 requires a working pitot system for reliable attitude information. 

 *Attitude*.  Not just airspeed.  I don't want to turn an inadvertent 

 icing encounter into an emergency (and I consider flying 

 needle-ball-and-airspeed with failed airspeed in IMC an emergency).

nuckolls.bob(at)aeroelect
Guest

Posted: Mon Oct 05, 2009 6:04 am Post subject: 24V Heated Pitot

At 12:48 AM 10/5/2009, you wrote:

 	  Quote: 	
		  



In spite of my best efforts to avoid thread drift ...


	


   The "drift" wasn't intended to persuade or dissuade

   you of anything. It's a prophylactic measure to

   ward off misunderstanding by some of 1799 other

   readers who might believe that serious discussions

   about heated-pitot tubes on single-engine aircraft

   is a worthy topic for their attention as well. I

   and others on the list will be pleased to help you

   achieve your design goals. But the charter for

   this List is to seek useful perspective of any

   design goal based on physics, experience and

   understanding.



 	  Quote: 	
		  All I want to do is have a reliable source of dynamic pressure at 

all times.  It's not a secret but neither is it well known: the 

Dynon EFIS requires a working pitot system for reliable attitude 

information. *Attitude*.  Not just airspeed.  I don't want to turn 

an inadvertent icing encounter into an emergency (and I consider 

flying needle-ball-and-airspeed with failed airspeed in IMC an emergency).


	


   It's not possible to quantify "reliable".

   The prudent FMEA calls for crafting a

   Plan-B based on your Dynon system failing

   for what ever reason. We know that you're a

   careful pilot and will stay out of weather

   conditions that would put you at risk.

   So how does one handle an airplane

   if the airspeed readings are unreliable?



   It CAN become unreliable for a host of reasons

   not related to ice on the pitot tube.

   How about attitude and power control? Can

   you stall your airplane without putting the

   nose above the horizon?  How difficult is

   it to avoid over-speed?



   How about a wing leveler that uses it's own

   data sources? It's a much better needle-ball

   aviator than people and if you give it GPS

   course data, a damned good navigator too.

   It doesn't need a pitot-static system and

   leaves you free to concentrate on speed

   and altitude issues.



   One of my favorite teaching activities while

   doing check rides with prospective renters at

   1K1 was to show them how to keep their head

   out of the cockpit in our busy traffic area

   with lots of no-radio airplanes. It's good that one

   has the skills to nail that airspeed, runway

   centerline and cross the fence on target every time.



   It's equally good to skillfully execute a short

   approach from the downwind leg with high airspeeds

   and maneuvers that would have your instructor

   frowning if not yelling at you. It's the

   unusual flight maneuvers that can be safely

   conducted by staying WELL INSIDE the machine's

   controllability envelope. That same skills and

   understanding would do well by you if you

   discovered that some bit of instrumentation

   was broken for what ever reason. Skill and

   understanding are a better substitute for

   non-quantified "reliability" upon any single

   piece of instrumentation.

        Bob . . .



         ---------------------------------------

        ( . . .  a long habit of not thinking   )

        ( a thing wrong, gives it a superficial )

        ( appearance of being right . . .       )

        (                                       )

        (                  -Thomas Paine 1776-  )

         ---------------------------------------

nuckolls.bob(at)aeroelect
Guest

Posted: Mon Oct 05, 2009 6:04 am Post subject: 24V Heated Pitot

At 01:12 AM 10/5/2009, you wrote:

 	  Quote: 	
		  

Joe, get yourself the newest 5.1.1 version of the software and hook 

up a GPS that will give you additional comfort as with that version 

the attitude is, in case of dyn. press. lost backed up with GPS 

speed. (Interesting to see on takeoff roll when a message tells you 

that before the pitot comes live.


	


   Aha! A Plan-C  . . . good show.

        Bob . . .



         ---------------------------------------

        ( . . .  a long habit of not thinking   )

        ( a thing wrong, gives it a superficial )

        ( appearance of being right . . .       )

        (                                       )

        (                  -Thomas Paine 1776-  )

         ---------------------------------------

jdubner(at)yahoo.com
Guest

Posted: Mon Oct 05, 2009 11:14 am Post subject: 24V Heated Pitot

Thank you, Werner.  I /do/ have that version of software installed with 

a GPS connected.  I /have/ seen the warning message pop up (mostly on 

landing roll -- rather disconcerting) and it does give me additional 

comfort but as in all things involving proprietary (closed to scrutiny) 

software and sketchy specifications, I'm not sure if that replaces the 

need for a heated pitot tube in my application.



Maybe I'll call Dynon and ask.



Best,

Joe



Werner Schneider wrote:

 	  Quote: 	
		   

 

 

 Joe, get yourself the newest 5.1.1 version of the software and hook up a 

 GPS that will give you additional comfort as with that version the 

 attitude is, in case of dyn. press. lost backed up with GPS speed. 

 (Interesting to see on takeoff roll when a message tells you that before 

 the pitot comes live.

 

 Werner

>

> All I want to do is have a reliable source of dynamic pressure at all 

> times.  It's not a secret but neither is it well known: the Dynon EFIS 

> requires a working pitot system for reliable attitude information. 

> *Attitude*.  Not just airspeed.  I don't want to turn an inadvertent 

> icing encounter into an emergency (and I consider flying 

> needle-ball-and-airspeed with failed airspeed in IMC an emergency).

>

jdubner(at)yahoo.com
Guest

Posted: Mon Oct 05, 2009 11:48 am Post subject: 24V Heated Pitot

Thanks, Bob.  So how would I meet my design goal of reliable *attitude* 

information with a Dynon EFIS during inadvertent flight into icing 

conditions?  (For sake of discussion, I'll quantify reliable as pitch 

within 2 degrees of true, an MTBF of 2000 hours, and an indication of 

failure when it happens (no insidious failures).  Roll I don't care as 

much about as I can maintain wings level with an electric turn coordinator.)

My plan for dealing with failure of the EFIS is to fly 

needle-ball-and-airspeed using a TC, standby altimeter, and standby 

airspeed indicator.  But that's not a workable plan if combined with a 

simultaneous failure of the pitot system due to icing and the standby 

airspeed indicator is inop too.  Hence my requirement for a heated pitot.

While a wing-leveler autopilot is a good thing, I would also need a 

pitch-axis autopilot and both autopilots would need to be independent of 

the Dynon EFIS.  Alas, there goes the (relatively) inexpensive Dynon 

pitch and roll autopilot options.  Other solutions would be more 

expen$ive, heavier, and require more panel space.

So why not a heated pitot to make "plan A" more robust and "plan B" 

(standby instruments) possible?

--

Joe

Long-EZ flying

RV-8A building (wings)

Robert L. Nuckolls, III wrote:

 	  Quote: 	

 <nuckolls.bob(at)aeroelectric.com>

 At 12:48 AM 10/5/2009, you wrote:

> 

>

> In spite of my best efforts to avoid thread drift ...

   The "drift" wasn't intended to persuade or dissuade

   you of anything. It's a prophylactic measure to

   ward off misunderstanding by some of 1799 other

   readers who might believe that serious discussions

   about heated-pitot tubes on single-engine aircraft

   is a worthy topic for their attention as well. I

   and others on the list will be pleased to help you

   achieve your design goals. But the charter for

   this List is to seek useful perspective of any

   design goal based on physics, experience and

   understanding.

> All I want to do is have a reliable source of dynamic pressure at all 

> times.  It's not a secret but neither is it well known: the Dynon EFIS 

> requires a working pitot system for reliable attitude information. 

> *Attitude*.  Not just airspeed.  I don't want to turn an inadvertent 

> icing encounter into an emergency (and I consider flying 

> needle-ball-and-airspeed with failed airspeed in IMC an emergency).

   It's not possible to quantify "reliable".

   The prudent FMEA calls for crafting a

   Plan-B based on your Dynon system failing

   for what ever reason. We know that you're a

   careful pilot and will stay out of weather

   conditions that would put you at risk.

   So how does one handle an airplane

   if the airspeed readings are unreliable?

   It CAN become unreliable for a host of reasons

   not related to ice on the pitot tube.

   How about attitude and power control? Can

   you stall your airplane without putting the

   nose above the horizon?  How difficult is

   it to avoid over-speed?

   How about a wing leveler that uses it's own

   data sources? It's a much better needle-ball

   aviator than people and if you give it GPS

   course data, a damned good navigator too.

   It doesn't need a pitot-static system and

   leaves you free to concentrate on speed

   and altitude issues.

   One of my favorite teaching activities while

   doing check rides with prospective renters at

   1K1 was to show them how to keep their head

   out of the cockpit in our busy traffic area

   with lots of no-radio airplanes. It's good that one

   has the skills to nail that airspeed, runway

   centerline and cross the fence on target every time.

   It's equally good to skillfully execute a short

   approach from the downwind leg with high airspeeds

   and maneuvers that would have your instructor

   frowning if not yelling at you. It's the

   unusual flight maneuvers that can be safely

   conducted by staying WELL INSIDE the machine's

   controllability envelope. That same skills and

   understanding would do well by you if you

   discovered that some bit of instrumentation

   was broken for what ever reason. Skill and

   understanding are a better substitute for

   non-quantified "reliability" upon any single

   piece of instrumentation.

        Bob . . .

         ---------------------------------------

        ( . . .  a long habit of not thinking   )

        ( a thing wrong, gives it a superficial )

        ( appearance of being right . . .       )

        (                                       )

        (                  -Thomas Paine 1776-  )

         ---------------------------------------

mprather(at)spro.net
Guest

Posted: Mon Oct 05, 2009 12:16 pm Post subject: 24V Heated Pitot

I suspect Dynon might wash their hands of the whole thing by saying

something like "the use of our pitot or display for the primary instrument

for flight in icing condition is not recommended."



I'll be interested in hearing back what they say..

Matt-

 	  Quote: 	
		   



 Thank you, Werner.  I /do/ have that version of software installed with

 a GPS connected.  I /have/ seen the warning message pop up (mostly on

 landing roll -- rather disconcerting) and it does give me additional

 comfort but as in all things involving proprietary (closed to scrutiny)

 software and sketchy specifications, I'm not sure if that replaces the

 need for a heated pitot tube in my application.



 Maybe I'll call Dynon and ask.



 Best,

 Joe



 Werner Schneider wrote:

> 

> <glastar(at)gmx.net>

> Joe, get yourself the newest 5.1.1 version of the software and hook up a

> GPS that will give you additional comfort as with that version the

> attitude is, in case of dyn. press. lost backed up with GPS speed.

> (Interesting to see on takeoff roll when a message tells you that before

> the pitot comes live.

>

> Werner

>>

>> All I want to do is have a reliable source of dynamic pressure at all

>> times.  It's not a secret but neither is it well known: the Dynon EFIS

>> requires a working pitot system for reliable attitude information.

>> *Attitude*.  Not just airspeed.  I don't want to turn an inadvertent

>> icing encounter into an emergency (and I consider flying

>> needle-ball-and-airspeed with failed airspeed in IMC an emergency).

>>

nuckolls.bob(at)aeroelect
Guest

Posted: Mon Oct 05, 2009 3:13 pm Post subject: 24V Heated Pitot

At 02:34 PM 10/5/2009, you wrote:

 	  Quote: 	
		  



Thanks, Bob.  So how would I meet my design goal of reliable 

*attitude* information with a Dynon EFIS during inadvertent flight 

into icing conditions?


	


 	  Quote: 	
		    (For sake of discussion, I'll quantify reliable as pitch within 2 

 degrees of true, an MTBF of 2000 hours, and an indication of 

 failure when it happens (no insidious failures).  Roll I don't care 

 as much about as I can maintain wings level with an electric turn coordinator.)


	


   GPS aided wing leveler would do it for you. I think

   TruTrak has a version that adds the turning rate

   indicator on the panel.



 	  Quote: 	
		  My plan for dealing with failure of the EFIS is to fly 

needle-ball-and-airspeed using a TC, standby altimeter, and standby 

airspeed indicator.  But that's not a workable plan if combined with 

a simultaneous failure of the pitot system due to icing and the 

standby airspeed indicator is inop too.  Hence my requirement for a 

heated pitot.


	


   It's not hard to find ice free locations for good

   static pressure data. Which is the foundation for

   pitch management. Further if altitude change rate

   is zero, then actual IAS is not terribly important

   data for flight safety. GPS ground speed and course

   readings and/or compass will get you the recommended

   180 degree turn to exit icing.



 	  Quote: 	
		  While a wing-leveler autopilot is a good thing, I would also need a 

pitch-axis autopilot and both autopilots would need to be 

independent of the Dynon EFIS.  Alas, there goes the (relatively) 

inexpensive Dynon pitch and roll autopilot options.  Other solutions 

would be more expen$ive, heavier, and require more panel space.


	


   ???? How much time do you expect to spend out of

   sight of the ground in this airplane? How much of that

   will be in the dark? If you're willing to fly needle-

   ball-and-airspeed as a backup for electronics, then

   needle-ball-altitude-VSI-and-gps data are excellent

   expansions of that capability without adding weight,

   expense or taxation of panel space. The wing

   leveler with GPS augmentation is a HUGE reduction

   in workload while you deal with matters of pitch,

   power and navigation.



   What is your personal modus operandi for dealing

   with the first perceptions of icing? If it's even

   a possibility, do you have a flashlight or leading

   edge ice light that will let you watch the place

   where ice is likely to be seen first?



 	  Quote: 	
		  So why not a heated pitot to make "plan A" more robust and "plan B" 

(standby instruments) possible?


	


   Because by the time you get icing severe enough to

   put pitot data at risk, the next level puts

   the airplane at risk. If your modus operandi calls

   for ASAP exit from icing conditions at first

   detection, then pitot heat is superfluous. This because

   your FMEA and Plan-B using other equipment already

   on board is quite robust even without airspeed data.

   If pitot heat offers ANY encouragement for pushing

   on to "see how much worse it gets" then I'll suggest

   it's more a hazard than help.



   I cringe when overhearing a C210 pilot talking to

   his hangar mates about the windshield patch,

   hot prop, boots and pitot tube heater, "Man, I

   can take this bird anywhere!"  I prefer to (1) go

   flight into known icing cert or (2) get the hell out

   fast. The risks for anything in between are

   higher and perhaps incalculable. JUST heating

   the pitot tube is a very tiny reduction in

   risk.



   Bob . . .

glastar(at)gmx.net
Guest

Posted: Mon Oct 05, 2009 9:55 pm Post subject: 24V Heated Pitot

Hi Joe,



I think it is down to your mission profile, I would avoid icing 

condition at all if possible but might go through a thin layer of 

stratus occasional, I did test the GPS assist in flight (hooking of the 

pitot line) and it worked quite well (stable attitude reference all the 

time). However I have the Dynon  heated pitot with AoA installed as well 

(had a 5812 before). I had some thin layer of rim ice skimming under a 

stratus layer some times but I try to avoid these conditions as without 

de-icing on my plane/prop I feel not safe enough. A friend of mine even 

hooked two Dynons on different pitots in order to have redundancy.



Again your mission will dictate what you want I would say.



br Werner



Joe Dubner wrote:

 	  Quote: 	
		   



 Thank you, Werner.  I /do/ have that version of software installed 

 with a GPS connected.  I /have/ seen the warning message pop up 

 (mostly on landing roll -- rather disconcerting) and it does give me 

 additional comfort but as in all things involving proprietary (closed 

 to scrutiny) software and sketchy specifications, I'm not sure if that 

 replaces the need for a heated pitot tube in my application.



 Maybe I'll call Dynon and ask.



 Best,

 Joe



 Werner Schneider wrote:

> 

> <glastar(at)gmx.net>

> Joe, get yourself the newest 5.1.1 version of the software and hook 

> up a GPS that will give you additional comfort as with that version 

> the attitude is, in case of dyn. press. lost backed up with GPS 

> speed. (Interesting to see on takeoff roll when a message tells you 

> that before the pitot comes live.

>

> Werner

>>

>> All I want to do is have a reliable source of dynamic pressure at 

>> all times.  It's not a secret but neither is it well known: the 

>> Dynon EFIS requires a working pitot system for reliable attitude 

>> information. *Attitude*.  Not just airspeed.  I don't want to turn 

>> an inadvertent icing encounter into an emergency (and I consider 

>> flying needle-ball-and-airspeed with failed airspeed in IMC an 

>> emergency).

>>

jdubner(at)yahoo.com
Guest

Posted: Tue Oct 06, 2009 4:22 pm Post subject: 24V Heated Pitot

Ah, now I see the source of the confusion -- a typo that I made.  Larry 

MacDonald Emailed me about it too but we didn't figure it out until you 

posted, Bob.  Thanks.



Yes, the data plate says it's a 24V model.  And I'd like to trade it for 

a 12V model.  Somehow I had 14V on my mind 



--

Joe

Robert Mitchell wrote:

[quote] 

 

 On the data plate it says 24V?  You didn't really mean 14V?

 Bob Mitchell

 L-320

 

 --

riggs_la(at)yahoo.com
Guest

Posted: Tue Oct 06, 2009 6:14 pm Post subject: 24V Heated Pitot

It is possible to get pitot tube icing without getting structural icing.  I

have had this happen on several occasions', so you are justified in your

concerns.

Lynn A. Riggs

BH 656 Kit 22



--

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