I am working on a long range uav, 100 miles+, and need some information on the pros and cons of using gas engines. The engine I want to use is the saito FG-14, if someone can convince me that electric is better then I am open to it, but remember that this is a long range project. Aircraft speed needs to be around 30 mph for good image overlap of still imagery. Really gooey engine mounts/vibration dampeners would be used to reduce image blur from vibration. Shielding from spark ignition would be done as well.
Is there any quantitative data that gas engines are more dangerous than lipo batteries with respect to crash and resulting fire?
Thanks in advance
Replies
Is this project still something you are working on?
I would recommend a Zenoah engine. They are a very high quality engine that should run for a very long time. Sold through Horizon Hobby. Here is a link to there home page.
http://www.zenoah.net/node4102.aspx?nid=243695
If you're thinking of using gas powered engines, you'll have more of an engineering challenge than just gas vs battery safety.
The power curves on gas engines is very different from ESC controlled electric motors. It's great for providing thrust on fixed wing craft, but I'm not sure you'll have enough throttle control for quads. Since quads with fixed pitch props require that the speed of motors vary within a larger band, the gas engine may stall at lower speeds. One solution may be to use variable pitch propellers like this guy did:
https://www.youtube.com/watch?v=rcubbloN4HU
But, he's not very successful, I think.