The management of Byrge 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 5 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 $396,300. (Ignore income taxes.) Click here to view Exhibit 12B-1 and Exhibit 12B-2, to determine the appropriate discount factor(s) using the tables provided. How large would the annual intangible benefit have to be to make the investment in the aircraft financially attractive?