I have a fair amount of ice experience in a 4-P.  If you fly IFR you will get ice sooner or later.  I have had bad ice with no forecast ice, and absolutely no ice with forecast ice.  You just never know when it will happen, but it will happen. 

 

One of the worst issues is the alternate induction air system that opens when the induction air is iced up.  The alt air door opens and uses hot cowl air which gives you a hot engine.  So when you need power the most with a load of ice you have to deal with reduced power to keep the engine from overheating CHT’s.  It’s really no fun.

 

I think the most important issues to solve are propeller ice and induction ice.  I have heard of one 4-p driver who flew with 6 inches on the leading edges, but he had full power available as his alternate air system did not overheat his engine.  He had an MT prop which for some reason does not ice up, in my experience, like the metal props.  Keep it waxed or with a metal prop have prop deice.  Having baseball bats as propellers will not work.

 

I could never get my alt ind air to work without a hot engine.  A K&N filter helped some.  I would have a manual lever to open the alt air door so that you know how that system will work before you need it.  Make sure it can somehow get as cool air as possible.  I have talked to other experienced owners with the same problem.

 

Another fun event I had was an iced up static air system.  I landed thru heavy snow that turned to rain before landing.  It rained hard all night and I was parked outside.  I departed into forecast ice, encountered no ice, but did freeze up the static air.  No airspeed, VS, altimeter, or auto pilot, and I was in the soup with my angle of attack system screaming “stall.”  I used power settings and my GPS to help out until I broke out at FL220.  I did have a collector on the static air system. 

 

I think the power and prop are the most important, with wing deice last on the priority list.  I have spoken to many people with wing deice systems (on certified planes) that very seldom use them.  Keep your prop free of ice, your engine power available with a good alt induction air system, and get out of any icing as soon as you encounter it.  My dealings with center is that they will get you to another altitude if you tell them you are encountering ice. 

 

I sold my piston and am doing a turbine.  I am making sure I have a good alternate induction air system, ice doors so I don’t flame out, and no wing deice.  I have looked at all the wing deice systems and decided to wait until they are more proven.  As long as I have power, a prop, and a backup plan I feel pretty good about my chances. 

 

Mike Custard in Bend is selling a NASA developed ‘thumper’ system.  To my knowledge it has yet to be ‘thumped’ in a Lancair in ice so nobody knows how that works with a composite wing over time.  Lancair is selling the glycol system. 

 

With a P fly around the bad weather when possible, don’t succumb to the ‘direct route’ thinking if you can add a little time to the flight but avoid the worst weather.  Maybe leave a little sooner or later than planned and avoid the heavy stuff.

 

Be sure to have a backup plan with a way out.  That is another issue.