A while back I asked about using klaxons from a battleship. Turns out there’s a maximum dB rating. But putting in anything dangerous falls under the ‘setting a trap’ laws.
At least for general aviation aircraft (small planes like mine) they’re not that much different from car headlights. Mine has three, 2 on wingtips (tightly focused, aimed slightly down) and 1 on the nose, more broadly focused, aimed straight ahead. Walking in front of them during night preflights, I can’t tell any brightness difference between them and my car.
In many cases, the lights you get will require a different voltage from your car (probably 28V) so you’ll need to convert to the correct voltage. I think, from an earlier conversation with a relative, that most airliner’s use 28V as well. Here you’ll find a listing of landing lights for sale.
Perhaps I should mention that most general aviation landing lights I’m familiar with have a shorter service life than car headlights? In which case… you might want to use car headlights instead.
You could just use one of those zillion candle-power spotlights that run off the cigaretter lighter you can (or at least used to be able to) get at sporting goods stores for like 15 bucks. Those are plenty uncomfortable to get shined in your face.
Yeah they’re not really all that bright. We have Dash 8s and the landing lights get checked visually on the daily inspection, I’m standing below the level of the wing so not staring right at them, but they don’t seem any brighter than car headlights. I’m sure you could find something brighter from a hardware store.