Interesting article, David - it's a pity they didn't include orange smoke and red rocket flares during the daytime tests, as of the other types of flare, even the hand held red pyro was invisible to the naked eye at just over 2 nm.
Graham: those sailing instructions look very sensible. I guess all they'd have to do is add a sentence or two to allow electronic flares. The question then is, what does one actually need in the way of electronic kit? If we take as an example e.g Pains Wessex pyrotechnic flare packs, their Inshore flare packs consist of:
Inshore (less than 3 miles from land): 2 x each of parachute red, red handflares
I assume the duplication of pyrotechnic flares is mostly due to their short operating time. You don't have to worry about that with electronic flares, and you can test them every time you get in the boat without materially affecting battery life. A recent Ocean Signal LED flare claims to have a range of 'up to 7 miles'. The Odeo LED flare claims to be visible at 3 nm at sea level, and 6 to 10 nm from a helicopter - and of course, these both operate continuously for hours, not once for 30 seconds. Both will flash SOS mode. More info on each at:
http://oceansignal.com/news/ocean-signal-develops-worlds-most-compact-electronic-distress-flare-the-new-rescueme-edf1/http://odeoflare.works/I suspect either of these (both operating close to sea level of course) might in some conditions have limited visibility compared to a parachute flare - which may be where laser flares come in. These appear currently to be available in UK from:
http://www.rescue-flares.co.uk/The site says that when used correctly, laser flares produce a brilliant red strobe effect, visible up to 20 mile away in optimal conditions.
So, once the emergency services are alerted by VHF/mobile phone/personal locator beacon or whatever, an LED or laser flare should pinpoint your position. If you're close to help, an LED flare flashing SOS might do the whole job, and compared to a laser flare, it's omnidirectional so you don't need to know where the chopper/lifeboat is coming from. If conditions are bad, perhaps a laser flare will cut through clouds etc. better providing you point it the right way? It's not quite so clear what the electronic alternative to an orange smoke is during daylight, but if you're in even a small vessel and transmitting your position with a beacon, a) do you need to worry about that, and b) how much confidence do you have that someone will see your orange smoke in the 1 minute it burns?