Schipmunk:

The switch you use to power the ignition with the battery pack is your kill switch. In other words, use a heavy duty switch (JR or MPI, the same type you use on your receiver pack). Hook this up between the battery you plan to use for your ignition and the ignition's power wires. This will turn your ignition on & off and (of course) act like a kill switch as it's cutting the power to the ignition. No power (battery pack) no spark for the engine. I've been using a 1400 mHa 4-cell pack NiCad for my BME50 ignition. You can get a bit over 2 hours of continuous use with that amount. Some guys use more, some use less.

As far as installation of the BME in the GP Patty Extra, there's no issues at all. In fact you can even use the motor mount they give you for a glow engine. It's big enough and strong enough for the BME50 and since the BME fits a standard motor mount it's a easy setup, just like a glow engine. Some guys swap out the GP motor mount with a metal one. It's a good idea, but not necessary. When you do this, let me know and I can post some pictures for you on how it's done and how the cowl gets cut out.

If your concerned with RFI from the ignition here's what you do. Most of the BME50's that are out there have the old ignition on it. Actually it's the same ignition module, but there's upgrades you can do (or CH can do) to make RFI almost non-exsistant. First is to change the rubber boot spark plug cable with a Bosch cap. (With the Bosch cap you will need to change spark plugs to a short 3/4 hex by 14mm plug. Not a big deal, they are available from your local car parts store or CH and brands are NGK or Champion.) It's just because the Bosch cap only fits these size plugs. The second thing you can do is to replace the hall sensor wires. CH has a upgrade that includes a grounding wire which makes all the difference in the world in keeping RFI from getting back to your receiver. If you have your BME, look at the wires coming off the hall sensor. There's 3 wires there. If you have 4 wires coming off the hall sensor (at the engine) then you have the new ground update. If you only have 3 coming off the sensor by the engine then you need to up grade it to the 4 wire system.

Now, I successfully flew my Patty with the old rubber boot and 3 wire systems all summer long. I had a couple glitches, but nothing serious. When I built I took the time to follow the rules and keep all your ignition & ignition battery & switch at least 12 to 18 inches away from the receiver & it's battery pack & switches. Now that I upgraded the system there's no glitches or RFI at all. Quite a improvement and I feel much safer now.

I'd be glad to answer any questions you have about the Patty. Just ask. I'm on my second one, because I like how well it flies. It's outstanding.