Emergency signalling

[TLM]

How about a hexxy block that's been carved into a sharp pointy shape?

No, no, no you sink it into nitric acid first then do something ...

 

[mrmike]

How about a hexxy block that's been carved into a sharp pointy shape?

And then shoot it from a crossbow?

 

[BrewkitAndBasha]

I would agree on a smoke flare being effective but only use SOLAS (Safety Of Life At Sea) approved, not fireworks. They are available at yacht chandlers to the public and there are no restrictions on possession apart from criminal usage. A flare is carefully designed to function safely in hand or on raft with a known length of burn.

SOLAS ones can be hand held with an insulated handle (no dropping things in a life raft) and a Day/ Night double ended version is my carried preference. About £50 a pop. Smoke one end and a flare at the other which also produces a handy amount of smoke.

Offshore kits have a multiplicity of mandated signals though. Think of them as a system for you last chance of being spotted and include either miniflares and/or hand held parachute flares and multiples thereof as you are a very small target. You only have 2 bites at the cherry with a single unit.

Obey the sell by dates. I've seen failures to fire on out of date ones. I wouldn't go cheap as literally your life may depend on it.

I'd also go for a day/night flare if they're available to me. Good kit.
In my experience though, Miniflares can be blown sideways or into the ground, if there's a strong breeze, quite soon after being launched.
A radio link to a chopper pilot is great but one needs to be very confident of describing the incident/recovery location clearly (especially at night), when the rescuer's viewpoint may look different from yours. If a leader needs to be rescued, have others in the team been trained to use the radio and describe the terrain for a helicopter approach?
I always carry lightweight coloured marker panels or, cheaper and more versatile, an orange plastic survival bag (6' by 3') to indicate position. Illuminated inside with a torch or candle, they show up pretty well at night.
Redland laser flares are good for penetrating forest canopy gaps and the beam goes up thousands of feet with a wide spread the higher it goes. Good kit but somewhat pricey.
Some EPIRBS have a strobelight on them (ACR) and a strobelight reflected off a space blanket also does a good job.
Heliographs also still have a place in signalling, especially on a sunny UK mountainside.