Some of you might know him its Geoff Bennett Upholsterer in Newton Abbott, he's a keen kite flyer and maker of some fancy Kites for shows and competitions. He quite often does night flights, aerial photgraphy and various other things with these kites.
What he would like to do is rather than wind in a kite to prepare for night flights with lights he would like to have a remote control where it can just be brought in to around 100/150 meters and switch on via a remote control. Weight isnt too much of an issue as he has been known to lift beer kegs and car batteries in weight lifting competitions.
Any advice or direction to go in would be greatly appreciated
I'd like a look at that, power kiting is one of my past hobbies. If he wants the lights to switch on at dusk I'd be using a photo light sensor, I think I have some here.
yep, any of the above or use a low power dusk sensor to turn them automatically. You should be able to find plenty around nowadays as they are popular for use with solar powered garden lighting. You could also butcher one of those solar lights to get to the controller.
Just package it in a waterproof box and use a 12V DC power source - like a battery drill power pack.
It may try to kill the batteries though as it won't know when they have reached their discharge limit. You could also use disposeable batteries but if you're just powering a few LED's and you have wired them up in series/parrallel to run at the lowest total current, then you shouldn't drain the battery pack during a days use.