The Cree XML T6 LED is used in many currently available "bright lights".

http://www.cree.com/~/media/Files/Cr...g/XLampXML.pdf

About 1000 lm ea at max power. There are many bike lights available that use 2 or more of these, and they are great for seeing where you are going (about like a single car headlight), most have a flash mode for daytime. I have one that's typical of the breed.

None of these are going to be useful for blue sky collision avoidance in aviation. Bright as they are, they simply aren't bright enough.

Medium and high intensity obstruction lighting strobes give some indication of what it takes to be clearly visible on bright days at aviation-useful distance.

For instance:

http://www.flightlight.com/airportli...2.3/5.2.3.html

best,

Evan Ludeman / T8