I really never understood the point of EDC on an airplane. The way I look at it, I've got about 2-3 hours between on and off the plane. If anything happens in that time, I'm in an airport. If anything happens on the plane, it's a contained environment. So... not like I need to signal help, build a fire, skin a squirrel. And if the plane crashes your SOL anyway, right?

OK, so, to answer your question and get off my soapbox... compass, whistle, you could probably take a mag bar for fire lighting purposes. Paracord, wire, a light, extra batteries, some food, water, ID, spare cash. A blanket if you get cold. Pretty much if you search for "EDC" and take the knife and multitool out of the equation, you're safe. Check with the TSA website, I've heard that matches may be OK lately. You MIGHT be able to get one of the Swiss tool 'key' item onto your keychain and sneak it on board. Or not.

No idea about Brit laws on knives. I suppose you could just carry a beer mug around and use it as a blunt-force instrument.