Electric vs Nitro engines weight

Anthony M

Hi everyone, im currently building a 1/9th scale balsa spitfire and am coming to the point of what to power it with. My biggest concern is weight. Taking into consideration nitro engine, engine mount with fuel vs electric motor, larger batery, ecu, what will weigh more? Also what would be the cost of flying with nitro for half an hour? I appreciate your replies. Thanks

coolwings

In general, a .40 cu inch size engine low wing plane would have a 50-55 inch wingspan.
So a 1/9 would be about 48-50" and be close to your specification.

Is the design made for electric or glowfuel engine? There are huge differences in strength at the front end to take the vibration of a piston engine. Modifying a design is absolutely do-able, not really difficult, but probably not a good idea if you are inexperienced.

Where the nitro engine wins is when you have a precut grass runway to take off from. Like eg a model flying club runway. Nitro does grass takeoff power at a lower cost than electric, when backup gear is included.

The ground gear you already have ownership of is therefore also very important in accessing the easiest or lowest cost way to choose.

In general I prefer electric, but for larger models the batteries are not cheap!

For lively flying suitable for such a model you will need 100-150 watts per kilo of flight weight, and the motor/battery/electronic speed controller would have to reflect that power requirement or if not have a short lifespan. For comparison the nitro engine might be 120 watts per kg. if two stroke. Four stroke costs more and is nicer.