Mailing List lml@lancaironline.net Message #42848
From: Douglas Brunner <douglasbrunner@earthlink.net>
Sender: <marv@lancaironline.net>
Subject: Re: [LML] To de-ice, or not to de-ice, and if so, how?
Date: Fri, 29 Jun 2007 07:02:24 -0400
To: <lml@lancaironline.net>
While I don't consider myself an expert, I have given this topic a fair amount of thought and am planning to de-ice my Legacy.
 
I certainly don't advocate flying in "known ice", however even if you avoid flying in "known ice" you can sometimes encounter significant unknown ice, which is no more fun than the known kind.  I live in Baltimore and have had some scary encounters with ice over Western MD in April and November as well as a number of other less scary encounters including one over Ohio in August.
 
When I got my Mooney Ovation, I equipped it with TKS icing.  The icing install was done after I had the airplane for several months so I got to fly it before and after the installation of the TKS.  To make a long story short, I lost about 6 kts because of the TKS.  I think that you would lose even more than that on a Lancair because of the critical laminar flow wing.  On the other hand, if you put TKS on a fat Piper wing, or if you mold the leading edge to accept TKS as Diamond has done, you probably won't lose any significant speed.
 
I didn't find the TKS fluid to be too much of a pain, but others have complained about this aspect of TKS as well.
 
I have been told that electro expulsive is also thick and would cause a significant speed loss, but don't have any personal experience.  I presume boots would be the same - again no experience.
 
That leaves me with heated leading edge which is now being worked on by RDD in Redmond. The URL is: http://www.rddent.com/.  This is also the system that Columbia uses.  This is the system that I hope to have installed on my plane.  I know they have installed systems on IVs and ESs and suggest that you give them a call.
 
Doug Brunner
N241DB
?first flight - August?
----- Original Message -----
From: John Hafen
Sent: Thursday, June 28, 2007 7:21 PM
Subject: [LML] To de-ice, or not to de-ice, and if so, how?

Gents:

 

This is a philosophical question as well as a technical recommendation question.

 

A) would you consider a de-ice system for the IV-P?

 

B) if so, which technology would you use?

 

In general, I don’t believe in flying small planes anywhere near icing conditions (been there done that – sinking feeling when you are at full throttle and unable to maintain level flight – then your prop heat throws off a chunk of ice that hits the windshield like a brick…. Just to keep your heart rate and blood pressure way high off the chart.)

 

And, having said the above, after you have done everything possible to avoid icing conditions, and you still find yourself icing up, it would be nice to be able to do something about it other than pray, which I have done (“I promise to mend all my evil ways if you just help me out of this one…”).

 

So, philosophically, would you recommend a de-ice system?

 

If so, would you lean toward:

 

            Heated Leading Edge

            Electro Expulsive

            Glycol

            Rubber Boot

            Other?

 

As always, your thoughts/recommendations are welcome.  Thanks in advance.

 

John Hafen

Lancair IV-P N413AJ

2/3rds done (I pray)

 

PS – I LIVE IN SEATTLE – THE WEATHER IS ALWAYS SH1TTY, HERE.

 

 

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