This is my version of the Nightsun searchlight http://www.spectrolab.com/searchlights/pdfs/SX-16%20ENH%20020910%20REV%20C.pdf popular on so many recon helicopters.
This model was designed to support a 3W LED and it's heatsink
http://www.hobbyking.com/hobbyking/store/__28505__Super_Bright_3Watt_Red_LED_Lamp_with_Aluminium_Heatsink.html

It is approx 1/10 scale.
Shown here it's trial-mounted on my Century AS-350 Ecureil which BTW is now being retrofitted with an Arducopter autopilot system.