With regards to minimising human error, training, pay, experience and company culture needs to be altered. Firstly, are the guys happy? If not, then why? If so, how do you better the deal for them. I have worked in a previous airline where we had CPL holders earning in excess of AUD$250,000 tax free. Yes they were financially doing well but they all failed their commands several times and still substandard. My philosophy is not rocket science so here goes:
1) Are the guys happy at work.
2) Are the trainers well liked and respected?
3) Is training really training or checking?
4) Days off?
5) Leave allocation?
6) Family quality of life adequate or not?
7) Does management manage or dictate?
If the above was achievable, I am certain many guys will work for a lot less and stay longer.
Good luck.