Hi RacerBoy, thanks for the reply.
I've located a couple of sources on the web for naval distress flares. The first was originally introduced in 1959, reaches approx. 350m and burns red for 40+ seconds:
http://www.sailgb.com/p/parachute_rocket/
The second is more modern, burns orange (but same principle as red) and burns for approximately 20+ seconds:
http://ofbindia.gov.in/products/data...tion/gr/15.htm
Personally, I would reduce the current size of the flare itself by about a third, and leave a slight glow around it - too much and it won't look right in daytime.
As for the reflection on the sea, at a height of over 350 metres there wouldn't be much surface reflection on a rolling sea. Perhaps a few flecks of dark red here and there as the light catches the swell.
Cheers!
Px3000