RE: Extreme Flight Extra 300, 78
Dave,
There are no real disadvantages to the electric set-ups. Weight is a wash between a DLE55 powered andelectric powered model.An OS33 model would weigh about 1 pound less than either the electric of the DLE55.....
The biggest disadvantage of electric is flight time, if you use typical 10S, 5 amp batteries, compared to gasoline. The OS 33 model will fly 20+ minutes on 16 ozs. The DLE55 model will fly 20+ minutes on 24 ozs. The 10S, 5amp batteries will fly it for 7-8 minutes. You can always increase battery capacity and voltage similar to top end electric helis but remember anything more than 3750watts (5HP) is overkill.
Such was the case with the DLE55, 6HP+ (piped), which is 4500+ watts. Thrust was in the mid 30 lbs for a 13 lb airplane. BUTthe main take away should be that there was plenty of strength there to handle the power. The OS GT33 with its 4 1/2 HP output is a much better match.
There is also a new 40cc twin I am taking a close look at primarily for reduction in vibes. This whole enginewould fit inside the cowl.Engine weight is a scant 35 ozs, but with headers and pipes, it will be around 45-47 ounces. Should turn a 21-10 on pipes. Supposedly develops 4 3/4 HP on mufflesr so it will develop over 5HP on pipes