The Navy began considering in September 2014 cutting the number of Tritons it plans to buy. The intention has been to have twenty operational MQ-4C aircraft operational at any one time, with the rest of the sixty-eight-plane order force being spares. Due to the improved reliability of the aircraft, budget pressures may require the Navy to trim the numbers of aircraft it will order. In September 2015, the DoD Inspector General found the seventy-aircraft force requirement justified, based on available attrition rate estimates of four per 100,000 hours. The Navy intends to begin operation of one operating location every year starting in 2018 until there are five. Four Tritons will be operational at each base to maintain continuous flight, with the rest produced for testing, training, and loss replacement; the entire order is to be completed in 2032.