Couple of years back I had a colony turn very nasty. It exploded into several boxes in spring and had gone from that nice warm brown colour to darker with greyish bands, not as much as carnica but half way there. I'm pretty sure that it was a hybrid.

It was exceedingly difficult to work and just threw bees at you when you opened the top. Very intimidating. Usually I do my beekeeping in a jacket and veil, but as my thighs were getting peppered I turned to adding waterproof trousers, sealing up the pockets with Duck tape. Didn't work, they still buried their way through into my pockets and stung me from there.

Its a sample of one, but it fits with what others say about such hybrids. Some years previously I also had a colony turn nasty on re-queening but that was before I could hazard a guess at the racial identity.

These colonies are a danger to the beekeeper, especially the relatively inexperienced ones, and also by-standers.

So, probably not always hybrid = angry, but often it is the case especially with first backcrosses.