Jump to content
Sign in to follow this  
Rui

Anti-ice

Recommended Posts

Thsi question is along the lines of my pressurized cozy question a while ago (yes, I am a glutton for punishment...)

 

Anyway, we've had a bit of a storm blow through over the last day or so which produced a lot of severe icing conditions. Has anybody looked at anti-ice systems that would work on a fibeglass plane. I am not too familiar with anti-ice (other than the glycol that ramp attendants spray on the airplane prior to takeoff) so any general information that you can provide woould be useful as well. My limited knowledge would point to an electric system for weight reasons, but thats just my guess. How hard would it be to home-build such a system? Around hee some people use heat tracing wire on pipes to keep them from freezing, would it be possible to adapt this type of idea and embed heat tracing wire in the fiberglass and have a poor man's anti-ice? My worry is that it would overheat the foam/glass and cause similar poblems as painting the plane a dark color, but if some temp sensors were also embedded in the area....

 

Note: I wouldn't consider flying into icing conditions with this system. Basically it is a backup safety thing. If I inadvertantly fly into icing conditions it would be nice to have a system that could get me out of it.


Rui Lopes

Cozy MkIV S/N: 1121

Share this post


Link to post
Share on other sites

As a michigander I would love it!!!! Right now the only thing is a canard control coverplate


maker wood dust and shavings - foam and fiberglass dust and one day a cozy will pop out, enjoying the build

 

i can be reached at

 

http://www.canardcommunity.com/

Share this post


Link to post
Share on other sites

Rui,(This is all my opinion only!)

A de-ice set up would be possible for a canard aircraft.Your typical light aircraft de-ice set up uses a pneumatic system,which utilizes deicer boot construction with an engine-driven positive displacement type air pump(vacuum pump) and of course all the solenoids,distributor valves,dump valves and on...and on....and on...and on.Or,you could put together a poor man's type that is built with existing boots,tubing,a couple of valves, and a divers pony bottle.Pretty unbelievable,huh?


Joe Cygan

Cozy MKIV #1022

Southern California

Share this post


Link to post
Share on other sites

Ok, if its pretty simple why haven't I seen any other builders do it? Is it mostly because they don't fly in areas where this might cuase problem (something which I don't believe in a cross country plane), or is the danger not considered important enough?

 

I am doing my pilot training now, so don't have any experience in the real world of flying, but the Met part of ground school placed a pretty high importance on the dangers of airframe icing (ie. I came away with the idea that if you're unlucky enough to hit moderate to severe icing you could kiss your ass goodbye, is this not the case?).


Rui Lopes

Cozy MkIV S/N: 1121

Share this post


Link to post
Share on other sites

Rui,(This is my opinion only)

We'll,good question!Most people I know that build planes are afraid to think outside the box.In itself,this is a good thing.Because,failure can generate death and that's not a good thing.

First of all,you really don't need all that crap on your plane.Most people with some type of common sense, do a good job staying out of known icing conditions.If the weather sucks,stay on the ground,problem solved.

 

Joe Cygan

CozyMKIV #1022


Joe Cygan

Cozy MKIV #1022

Southern California

Share this post


Link to post
Share on other sites

...oops!I meant to spell "Well",not"We'll".I hope there's no spelling police around here.


Joe Cygan

Cozy MKIV #1022

Southern California

Share this post


Link to post
Share on other sites

Ya'all gotta be kiddin', right?? Just pullin' my chain, right??

Composite airplanes typically have laminar flow airfoils which are more efficient. That's because they can. Other materials can't be built smooth and regular enough for laminar flow, but composites can.

Trip the boundary layer, and you've got a different airfoil. The EZs with GU canard typically wouldn't fly right in MIST, let alone rain. Get in a cloud (white, not dark) or sometimes even NEAR one, and you get a nose down trim change from tiny tiny droplets of mist tripping the boundary layer. They had to jump through a lot of hoops to come up with one that would tolerate mist or rain (Roncz). Ice? Fuggedaboudit!!

I regard it as suicidal to have anything even remotely to do with ice in a composite airplane.

It scares the hell out of me ... and I'm FEARLESS !!! Jim S.


...Destiny's Plaything...

Share this post


Link to post
Share on other sites

Gee Jim,why don't you ruin all the fun.So far,we have a turbine powered,pressurized,retractable gear,de-ice booted CozyMKIV.What else can we do to it,pin stripe it!


Joe Cygan

Cozy MKIV #1022

Southern California

Share this post


Link to post
Share on other sites

Jim,

 

Your comments worry me somewhat. Do you (or anybody else) have any practical evidence of fiberglass canard's bad performance in icing conditions?

 

As I said before this wouldn't be for flying into known icing, but for gettting out of it once I find myself in it. I think I will be flying a lot in the mountains where weather changes rapidly and unexpectedly. If this type of airplane can't handle mild icing then I think this is an argument FOR putting some sort of system that may help you get out of a difficult situation.


Rui Lopes

Cozy MkIV S/N: 1121

Share this post


Link to post
Share on other sites

Joe,

I suppose we could put on a BRS. Of course, with the speed ranges we're talking about with turbines and superchargers, it would have to be at least a two stage system - one maybe 5' - 8' canopy to slow down below 80 kts and a great BIG one to deliver the plane gently to terra firma. Sould only weigh a couple hundred pounds.

 

Rui,

I don't have direct experience with icing on composite (Rutan derivative) airplanes. There are folks who do. Most are dead. I took that as a strong message.

Known icing only hurts idiots. Folks who fly composits into known icing conditions are candidates for the "Darwin Award". Unknown icing is what kills folks who can read and write and count to twelve (but are still not the brightest candles on the tree). If you read the CPs, you will find that Burt is against going anywhere near even potential ice. He is not nearly as indirect and circumspect as I am in articulating his views on the matter.

If you really feel like "thinking outside the box", please be sure and let me know when you get it up and ready to go. I will want to take out an insurance policy on you (I'll even split with your widow).

Best of luck .... Jim S.

PS Is there a branch of your family named "Knevel"?


...Destiny's Plaything...

Share this post


Link to post
Share on other sites

now wait a minuite, that parachute plane is putting weepers on the leading edges, last time I checked it was composit/plastic airplane and ifin I can figure it out, I will too.

 

Mike


maker wood dust and shavings - foam and fiberglass dust and one day a cozy will pop out, enjoying the build

 

i can be reached at

 

http://www.canardcommunity.com/

Share this post


Link to post
Share on other sites

>Jim Said: I don't have direct experience with icing on composite (Rutan derivative) airplanes. There are folks who do. Most are dead.

 

Hold up a minute here, Jim. Lets have some data, rather than wildly screaming "Oh sh.t, we're gonna die".

 

How many NTSB reports indicate icing as the cause of a canard accident? I've read reports (written by the pilots afterwards) of mild icing in Cozy's. Why do we put ice shields on the elevator weights?

 

I've been in icing with a cessna, and it wasnt fun, and I'll quickly avoid and/or remove myself from any icing conditions I hear about or encounter - but lets not give the impression that the canard will immediately fall out of the sky if it gets wet, cold or both. Any airplane will fly like sh.t with ice on the airfoils. The trick is to recognize the problem and get out of the icing zone quickly. Sometimes this means climbing, and with a 172 at 8000 ft that can be a real slow process. Often it means decent, and/or lateral displacement. Cozy's are real good at lateral displacement - in a Cozy you can be 50 miles away in 15 minutes.

 

Rui,

Rather than be concerned by tales beginning "I don't know, but I've been told....", I'd suggest some research - use Rick Maddy's search engine (on my web site links page) to search the cozy list archives. Search the NTSB data on line. Let us know what you find.

Regards,

John Slade


I can be reached on the "other" forum http://canardaviationforum.dmt.net

Share this post


Link to post
Share on other sites

Jim,

 

No, I don't have a death wish. And if you would actually read my messages you would see that. My intent with both pressurization and anti-ice is safety. Flying above nasty conditions and having a system that may help you get out of such conditions if you find yourself in them improves safety in my books. It seems like pressurization is out of the question, but nobody, including yourself has provided any reasonable, technical reasons why this can't be done. I don't consider scare-mongering comments about people dying in icing conditions to be a good reason against such a system. As I said before, I see such comments as a good reason to come up with a system that may help.

 

I guess you assume that I would fly into icing if I had an anti-ice system. A somewaht reasonable comment from stories I've read, but I have also read many stories where the weather forcast called for perfectly nice conditions and the pilot found himself, unexpectedly, in ice. If composite planes are so terrible in ice, this situation would result in a crash. If a lightweight, simple, and not very expensive system

can be developed to help in this case it would only be reasonable to do it.


Rui Lopes

Cozy MkIV S/N: 1121

Share this post


Link to post
Share on other sites

Rui,

Since we're discussing "how" rather than "why not", how about the following:

 

The main problem with canards and ice is probably the canard. Since I'm using water cooling I'm running coolant hoses to a heater core in the nose. It would be a fairly simple matter to embed pipes in the canard foam during construction with exits in the nose. Running coolant through these pipes might give you enough temperature rise to dislodge any ice. The weight penalty would only be a few pounds for the pipe.

 

Just a theory....


I can be reached on the "other" forum http://canardaviationforum.dmt.net

Share this post


Link to post
Share on other sites

John,

 

I do plan on doing reasearch on this. Thanks for the pointers. I tried the NTSB site a few times and after it rumminating on the subject for 5 minutes or so it came back with an error. I guess those 140,000 records are really long, or they have a LOT of people searching, or really slow hardware.... I'll try again when I have more time with hopefully better seach criteria.

 

About your idea, sounds reasonable, sort of a radiator just underneath the skin...... hmmm, speaking of a radiator just underneath the skin..... how about such a system for engine cooling??? Yes, I know I have a lot of crazy, half-baked, death inducing, ideas, but I think this is half the fun of building your own equipment....

 

Just thinking off the top of my head, I would think the coolant temp would be way above what the foam/glass can handle without causing structural damage. And then there's the possibility of a a leak.... But the possibility of a non-drag causing cooling system has a certain appeal....


Rui Lopes

Cozy MkIV S/N: 1121

Share this post


Link to post
Share on other sites

Rui,

I'm glad this Cozy list has a good sense of humor.At the same time it's really cool to see someone like you trying to figure out how to do something that would not be normally done.I'm certainly no expert or engineer but,if you need help,let me know.

 

Joe Cygan


Joe Cygan

Cozy MKIV #1022

Southern California

Share this post


Link to post
Share on other sites

Thanks Joe,

 

I am also not an engineer, I'm a software developer where having innovative ideas is usually a plus. I do realize, however, that building a physical thing is different than building a logical thing in software so I am very interested in what other, more experienced builders/real engineers think.

 

btw, it is common in the States to call a software developer an engineer. Where I live (province of Alberta) it is actually against the law to refer to yourself as an engineer if you do not have an engineering degree (I have Comp. Sci.).


Rui Lopes

Cozy MkIV S/N: 1121

Share this post


Link to post
Share on other sites

Rui,

Well,the only degree I have say's"high school" on it and a couple of years of junior college when I was getting my A&P.So,do they have engineer police looking around for diploma violators in Canada?

Dust,

I guess this is one of those do it for Johnny things,get it,get it?


Joe Cygan

Cozy MKIV #1022

Southern California

Share this post


Link to post
Share on other sites

Joe,

 

Well the policing body is the APPEGA (I think thats the acronym) which is the professional organization for engineers here in Alberta (I'm not sure whether other provinces have the same setup). Their members are expected to report violations to the organization which then talks to the company. Usually it all gets resolved, but APPEGA does have the provincial law as a stick if the company is obstinate.

 

The reason why I know this is that our company was acquired by an American company a while ago and they still refer to all us here as engineers (some of us do actually have an engineering degree so its not totally wrong, but....).

 

Have you had much experience with composite airframes in you A&P career?


Rui Lopes

Cozy MkIV S/N: 1121

Share this post


Link to post
Share on other sites

Rui,

The only experience I've had when I was able to use my A&P, was working with high-bred composites doing NDT on flight controls for corporate aircraft.I was involved with composites when I was in my late teens and was sent for a few weeks to a guy name David Ronenburg to learn composite lay-up and entry level mold design.He was a great guy and use to love his stories when he was a stuntman and professional skier.Wow,I can't believe that has been more than fifteen years ago.However my composite career pretty much ended there and I pursued tube and fabric stuff on the experimental level.I have recently involved myself in the last couple years w/composites and I'm re-learning it all over again.Actually,I've put my Cozy project on hold, while I play catch up on my Pitts Model 12 project.I do not work and I stay home all day and build stuff,can you believe that!Right!


Joe Cygan

Cozy MKIV #1022

Southern California

Share this post


Link to post
Share on other sites

Back to the subject at hand.. ;)

 

Some folks here seem to be implying that ice is the achilles heel for the Cozy. I've heard before about the sensitivity of canards to changes in airflow brought about by ice or misting/water dropets. As I understood it, the original airfoil used in all Rutan aircraft caused the plane to experience a noticable change in trim when the aircraft was flying in rain or heavy clouds. Something to do with micro-droplets of water altering the laminar airflow, and while another airfoil (roncz?) was less susceptible to this, it provided somewhat less lift. I also recall that later, after the airfoil had indeed been changed, someone experimented with grooving the surface of the original airfoil in such a way as to stabilize the airflow in the presence of water droplets, solving the problem.

 

Regardless, it sounds to me that the Cozy is no more or less dangerous than any other aircraft in icing conditions. I was always told that ice is a Very Bad Thing, regardless of aircraft. Since prevention is the best medicine, and I don't know of any incidents where icing caused a Rutan-designed or derived canard to crash, I'm not particularly concerned about suddenly crashing if I run into light icing conditions. If I find myself in severe icing conditions, then I'll probably be deserving of the next Darwin Award.

 

Finally, I have a possible concern about the concept proposed by John Slade: How well will the heat provided by these pipes under the skin be transmitted? Isn't fiberglass and foam a pretty good insulator? And if so, how much expansion can you expect in the material surrounding the pipes? I'd be concerned about a change in the shape of the airfoil caused by the expanding material. How would one test this?

 

I'm not against a de-icing system. Good idea, but probably uneccessary. However, as someone else said, we now have a twin turbine powered, pressurized, full retract, de-icing cozy that can be built in a 12x20 space with a knife and a smart-level. What say we go for variable geometry next?


Evan Kisbey

Cozy Mk IV plans # 1114

"There may not be any stupid questions, but I've seen LOTS of curious idiots..."

Share this post


Link to post
Share on other sites

>Isn't fiberglass and foam a pretty good insulator?

Yes. The pipes would have to run close to the surface

 

>And if so, how much expansion can you expect

not much, I think

 

>How would one test this?

Very carefully


I can be reached on the "other" forum http://canardaviationforum.dmt.net

Share this post


Link to post
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

Sign in to follow this  

The Canard Zone

×
×
  • Create New...

Important Information