That will vary greatly based on where a person resides and the optional deductions you wish to take (i.e. Single 0? Married 10? 401K deferral amount?) It's hard to give an approximate monthly take home average.

Assuming reserve for your first year:
1st paycheck = 35 hours
2nd paycheck = 38 hours

Deductions:
Federal taxes XX% (what's your bracket?)
Medicare 1.45%
SS 6.2%
State XX%
Local XX%
ALPA 1.90% (as of 1/1/14 after end of probationary year)
401k XX% (your choice; also will you choose the regular pre-tax 401k or the post-tax Roth 401k option?)
1/2 of Medical premium (will vary based on medical options chosen)
1/2 of Dental premium (will vary based on options chosen)
1/2 of LOL/LTD premium which is about 1-1.25 hrs of pay rate per month (Advice: DO NOT waive this insurance!)
RHA VEBA $1 per hour of pay earned (Supposed to be deducted on 2nd check only after previous month's total hours is determined)
There are also optional life insurance and personal accident insurance plans available to you if you desire.

These are some of the deductions I can think of off the top of my head. May not make it easier for you to figure out, sorry to say.