The flight-test program for the BAE Systems Nimrod MRA.4 maritime patrol aircraft is behind schedule, and costs have risen by $150 million in the past year, according to a UK government watchdog. The National Audit Office (NAO) referred to the long history of delays and cost increases to this troubled project, which AIN covered at the Farnborough airshow last July. The NAO identified shortcomings in planning and executing the flight-test program. The cost of fitting a stability augmentation system and stall identification device (SAS/SID) to the aircraft has increased from $7.5 million to $30 million, the NAO said. There have also been problems with the aircraft’s radar, electro-optical sensor and electronic warfare equipment, although most of these are expected to be resolved. The cost of bringing the three development aircraft to production standard would be $75 million, according to the NAO. Only nine production aircraft are on order, down from 21 when the program was first conceived in 1996. BAE Systems told AIN that the flight-test program had not been completed late last year as planned, but said that the MRA.4 would still enter service next year as required. “We are working with the Ministry of Defence on some capability enhancements that were not in the original contract, and exploring a range of options for the three development aircraft,” a spokesman added.