The management of Nagata Corporation is investigating buying a small used aircraft to use in making airborne inspections of its above-ground pipelines. The aircraft would have a useful life of 6 years. The company uses a discount rate of 13% in its capital budgeting. The net present value of the investment, excluding the intangible benefits, is -$326,237. To the nearest whole dollar how large would the annual intangible benefit have to be to make the investment in the aircraft financially attractive?