The fly radical and the fly kanji are exactly the same! Awesome!
When you fly, you generate a lot of heat (ひ) because you’re moving so fast through the atmosphere. Normally this heat would be a nuisance, but you’re a superhero so it doesn’t bother you. This is actually the reason you’re able to fly – you’re a superhero and super resistant to heat.
Currently there are no similar looking kanji which exist in the WaniKani learning system