More than a year after U.S. defense officials offered three
RC-135 Rivet Joint aircraft as a replacement for the same number of Royal Air Force BAE Nimrod R1 signals intelligence (SIGINT) aircraft, the UK Ministry of Defence has not made a decision. Senior RAF officers have said that the Nimrods perform a vital task, and they last month promised the UK Parliament that there would not be “a capability gap” when the Nimrods are withdrawn from service in 2011. But the Nimrod SIGINT replacement seems to have fallen afoul of the UK’s defense budget squeeze. The MoD told AIN that a decision would be made late this year, and the R1s would be extended in service if necessary.

The U.S. offer is to have three Boeing KC-135R airframes converted for the SIGINT role by L-3 Integrated Systems (L-3 IS) at Greenville, Texas, where the 17-strong U.S. fleet of Rivet Joints is maintained and upgraded. However, the MoD has been exploring alternatives, most notably whether the remanufactured version of the Nimrod due to enter RAF service next year in the maritime patrol role could also serve as a SIGINT platform. The MoD previously planned to keep the three Nimrod R1s in service with an upgrade codenamed Project Helix. To perform the work, the MoD selected a team led by L-3 IS and also consisting of BAE, LogicaCMG and QinetiQ and initially awarded them a study contract worth $21.7 million.

But sources on both sides of the Atlantic familiar with the study and the U.S. offer of Rivet Joints, told AIN that both the original Nimrod R1s and the remanufactured Nimrods were rejected as suitable platforms for Project Helix. They said that even the remanufactured Nimrod would offer only 60 percent of the required capability, because of power and aperture considerations. Moreover it could not be in service until 2015, and would cost three times as much to operate as the Rivet Joint. Although the U.S. offer was valued at up to $1.068 billion when notified to Congress last year, the sources said the actual cost to the UK would be closer to the $750 million that was originally budgeted for the Helix upgrade. Moreover, the UK would benefit from the economies of scale in support costs that are generated by the larger U.S. fleet, as well as some commonality with the RAF’s E-3D Sentry AEW fleet, they explained. Although the three airframes on offer to the UK are already 45 years old, they are the youngest KC-135s in the U.S. fleet; have already been updated with modern CFM56 turbofans and cockpit avionics; and are good for service until 2045, as are the U.S. Rivet Joints, the sources said.

BAE Systems told AIN, “Our Nimrod solution is technically feasible and affordable.” But the spokesman conceded that the company had yet to submit a formal bid for Project Helix because of “concerns over timescale.“ Meanwhile, the U.S. offer remains on the table as a Foreign Military Sale (FMS) deal, without any provision for offsets. AIN understands that U.S. officials have assured the MoD that unique British requirements and sensors–such as QinetiQ’s Tigershark communications intelligence (COMINT) system–could be incorporated in the three Rivet Joints for the RAF. This and other British technology might also find a place on the larger U.S. fleet, sources told AIN. An informed U.S. source also addressed British concerns that the Rivet Joint system concentrates on COMINT at the expense of electronic intelligence (ELINT). He said: “I know that the RAF [mission systems operators] are not happy but they will get over it. An Rivet Joint configuration is not as ELINT-oriented, but today’s environment doesn’t really need an ELINT-heavy system.”