ORIGINAL: MTK

If you ever saw how lightly built an 78'' EF Extra is built, you will realize that the piped 50cc gas engine on a pattern plane is NOT A PIPE DREAM. By Pattern standard, the EF Extra is a bit heavy out of the box. And mine, equipped with a DLE55, DA RTC header (stainless unit) and the ESComposites G55 pipe, weighed in at 12 1/2#. That's heavier than rules allow but not pachyderm heavy. There is weight to be saved on the header (the stailess unit weighs 5 1/2 ounces) and a bunch of savings on the model itself. Example, each wing panel weighed 20 ounces, the stB 12 ozs and the canopy weighed 10. Kept the stock 7/8'' carbon wing tube and it was plenty strong enuff

Did nothing extra to reinforce the Extra. The prop was a Mezjlik 20x12 3 blader. Guess what....this prop is lighter than a 19x11 apc that the guys are running on their YS170's

I weighed all of the components of the powerplant including the soft mount and stand offs. Weight was on par with electric set-ups except I lightened my DLE by 4 1/2 ounces. So all up with stock stuff, this set-up is around 5 ounces heavier than an E-set-up.

Now, you tell me: if guys can get electric models RTF at 10 1/2 #, why can't we get a 50cc class engine in a pattern plane and still make weight? BTW-the lightest stock 55cc engine is the BME58 Xtreme. Beautiful engine but the carb is ill located for pattern. The least expensive to machine and butcher is the DLE. So it was worth the investment to me to find out if this was doable