Doug's RC Page

40 Size Snow Skis

The following are plans and instructions for building a pair of snow skis for a .40 sized RC airplane running with tricycle landing gear. I built a pair and attached them to my Great Planes PT-40 Trainer and was amazed at how quick the takeoff was compared to my normal grass takeoffs. The skis were heavier, but the wax on the bottoms allowed for much quicker ground acceleration. The one problem with the skis as the are now is that the plane is not steerable at slow speeds and tends to nose into the wind fairly quickly. If I place a slight rib on the bottom of the skis I would not have any ground steering, but would be able to go straight with less wind problems. I've opted to keep them as they are for now as with a fairly quick taxi I can steer with the rudder and keep the plane on the runway. Note: When using JB Weld, make sure to rough up the metal surfaces with coarse sandpaper to allow better adhesion. Also make sure to avoid air pockets in the joint

QtyDescription
21/8" X 2" X 18" Aluminum (Ski)
* 21/8" X 1" X 16" Aluminum (Ski landing gear)
41/8" X 3/4" Angle Aluminum (Ski landing brackets)
4Bolt and Nut combo to attach brackets to landing gear
*Note landing gear can be made from a piece of 2" wide stock cut in half

  1. Remove tricycle landing gear from plane, save for spring.
  2. Cut skis to length
  3. Cut radius on tips of skis
  4. Bend the ski front by using a form, or by guestimation. Just make sure both skis in profile view are identical
  5. Cut the angle aluminum in 2" lengths.
  6. Rough up the ski tops where brackets will go and the bracket bottoms
  7. Use JB Weld to attach the brackets to the skis. Build one ski as a mirror image of the other (see bottom of the above image)
  8. Bend each aluminum landing gear so that the gear when completed has a flat area the same width as the plane body and a 1 inch vertical section at the end of each leg.
  9. Drill holes in 1 landing gear to fit the normal rear holes in you you tricycle gear location.
  10. Drill holes in both pair of landing gear to attach the bracketed skis to.
  11. Attach rear landing gear with screws in holes previously drilled.
  12. Attach Skis to rear landing gear with Bolt and nut combos.
  13. Attach front landing gear to skis with Bolt and nut combos.
  14. Use rubber bands to attach front landing gear to plane.
  15. Use parafine to wax the ski bottoms for quicker takeoffs and less ground resistance.

Photos