Hand-propping a VW aircraft engine
By configuring an aircraft engine for hand-propping, lots of stuff can be left off, leaving you with a much lighter engine that costs less.
- Jean Claude Junqua's IBIS predecessor (the prototype called 'Volucelle') didn't sport electric starting. JC told me that starting was effortless in all conditions he encountered. Additionally, JC made me aware of the fact that in case of a pusher aircraft, the one pulling the prop is positioned on the safe side of the prop.
- In the UK I found an electronic iginition system that makes hand-propping an easy and safe option - read about it on this electronic iginition description page.
- Steve Bennet and others whose opinions I respect confirmed JC's information about how easy it is to hand-prop a VW-derivative aero engine.
- Some of the people I respect even told me that air starts would still be possible, provided you have enough altitude to put your stick forward long enough....
Going for hand-propping gives a lot of opportunities for saving weight. The following list gives some ideas:
- no starter.
- no starter mounting brackets.
- no heavy conduit cable from battery to starter.
- potentially a smaller main battery.
- no accessory case since in my case due to the electronic ignition, there will be no magneto either.
Ok, the above describes some of the weight savings I'd end up by going for hand propping and installing an electronic ignition. Totalling these weight savings made me realise that perhaps it could be feasible to install an alternator on both sides of the engine. How's that for some added redundancy?
There's one open decision that might still see me install a starter system though: if I were to decide to drop the carb and go for electronic fuel injection, then I'd need the starter after all. Still, very likely I'm goig to stick with my carb, as fuel injection is so much more expensive and perhaps would put too much experimentation in my experimental.
Having said that, I haven't made up my mind on this one just yet - especially after learning that Jean Claude contemplates using fuel injection on his IBIS as well. I'll keep you posted
Also check out: VW-derived Aero Engine >> Electronic Ignition