I think there's s difference between doubting humanity of someone because of skin color or sexual orientation or natinality or whatever, and someone who voluntarily became a murderer as a day job.
The pilots can stop killing people any day. They continually chose not to.
Perhaps a more profitable line of discussion would be: On what basis would you say that this constitutes murder?
I would say that even humans who decided to become monsters (say, Unit 731, Mengele, Breivik, various serial killers, etc) deserve human rights and humane treatment in eyes of the law, because taking those away is a bad precedent for society.
The state should consider them people because the state has to consider everyone people, and making exceptions is very dangerous.
That doesn't mean we as individuals have to morally consider them as anything other than the monsters they are.
When you cast people into the realm of inhuman monster, you're also telling yourself a story that there is no possible way that you could potentially commit the same acts.
Which is, 99% of the time, a total lie. Humans are exceptionally good at creating moral justification for whatever the hell we want to do.
If you're convinced you are constitutionally incapable of committing monstrous acts, then you're not likely to engage in the self reflection that would allow you to catch yourself if you start heading down that path.
Then goes the spectrum. Suppose someone is taking your property, can you employ violence to protect it? What if there is 1% risk of death to the thief? What if its 10%?
I'd prefer the people whose job it is to make those assessments on a daily basis to have a strong moral and ethical framework, and to have the psychological and institutional support to maintain a connection with their humanity.