Avstar Aircraft of Washington, Inc.

10415 172nd St. E., Hangar A1
Puyallup, WA  98374
office (253)770-9964
or (253)770-0120
email:  avstarair@att.net

11-19-2000 Ask Mike! Archive
How do I prepare my plane for the coming freeze?

I live in northern Idaho.  I fly off of a grass strip and do not plow the snow. My plane is a P-35 with a IO-470N. It will be in the hanger for 3-4 months.  What should I do to get it ready for storage?

Dear Delbert;
Congratulations on thinking ahead.  Most aircraft owners just let them sit without considering the consequences.  If that was your case, I'd refer you to the Ask Mike! archive dated 03-14-99; however, let's get to your question.
This needs to be answered in two parts - powerplant and airframe.
Powerplant:  Teledyne Continental Motors Service Bulletin M91-5 discusses steps to be taken when a period of inactivity is anticipated.  I strongly recommend you follow this bulletin to the letter - especially if your engine is under warranty (the factory, and most engine overhaul facilities will not warrant any part that has been abused or neglected).  If it's not under a warranty program, I'm sure you don't want to spend money on a top overhaul due to neglect.

Airframe:  The Beech 33/35 Shop Manual, section 2 (servicing) has a part referring to storage.  (Most other aircraft manufacturers also have included a similar section in their manuals.)  You should read this, but the nutshell version is as follows.  First, secure the aircraft.  You mentioned that you were keeping it in a hangar; if it is a closed hangar (as opposed to an open "shade" hangar), tying the aircraft down is really not necessary. Second, prepare the engine for storage (please see my powerplant answer).  Third, the fuel cells should be kept full.  Beech recommends installing the pitot tube cover:  I'll take this a step further - I would recommend also taping over the static ports with an electrical or plastic tape (comes off easier after several months) that has a contrasting color to the surrounding paint.  Finally, it would be a good idea to remove the battery; if the charge deteriorates, it stands the potential for freezing, spillage of the acid wouldn't do your bird much good.
Going back to your hangar, if rodents (mice, etc.) are a remote possibility, put guards up around your landing gear to keep them out of your airplane; you can make some fairly easily by rolling aluminum, or a slick plastic sheet around each gear, then taping it together around the circumference.  A heated hangar is nice, but only if the temperature is kept constant; the cycling of temperature can cause condensation, affecting avionics, etc.
Lastly, make a list of everything you did to prepare the aircraft for this period of inactivity, so you don't have to rely on memory to undo everything (and don't forget the tape on the static ports!)
Gear Green,