The USAF is thinking of purchasing a improved automatic controller (no human required) at a cost of $100,000 that can make 4,000 target contacts per hour to replace USAF specialists that can, on average, make 1,000 target contacts per hour. Note that a USAF Specialist is paid a relatively low salary of $8/hour (but with good veteran benefits) and that the controller will require $1/hour maintenance costs. How many hours of target detection would it take to pay off this new controller?