Remplacement des Nimrod SIGINT

Three Nimrod aircraft were originally adapted for the Signals intelligence role, replacing the Comet C2s and Canberras of No. 51 Squadron in May 1974. The R1 is distinguished from the MR2 by the lack of a MAD boom. Only since the end of the Cold War has the role of the aircraft been officially acknowledged. Officially these were once described as "radar calibration aircraft". The R1s have not suffered the same rate of fatigue and corrosion of the MR2s and will continue in service long after the MR2 is replaced by the MRA4. New Bombardier Sentinel R1 (ASTOR) aircraft due for delivery from mid 2004 may take on some duties performed by the R1. One R1 has been lost in a flying accident since the type's introduction; this occurred in May 1995 during a flight test after major servicing, at RAF Kinloss. To replace this aircraft an MR2 was selected for extensive conversion, undertaken by BAE Systems at the Woodford factory, to R1 standard, and entered service in December 1996.

The Nimrod R1 is based at RAF Waddington in Lincolnshire, England and flown by 51 Sqn.

Des RC-135 britanniques

Faisant face à des problèmes chroniques de financement de ses appareils ELINT/SIGINT Nimrod R1, la Royal Air Force a obtenu de sa consoeur américaine la location de deux RC-135 Rivet Joint sur lequel, pour l’occasion, vont être apposées les cocardes britanniques.

Les équipages de ces appareils ne seront toutefois pas totalement britanniques. Les 3 R1 subissent les mêmes problèmes que le MR2 qui s’était écrasé en Afghanistan (la température en cabine montant, par exemple, à plus de 50°C).

Reste que la solution de la mutualisation est considérée comme la plus rentable, le remplacement des appareils – qui devaient rester en service jusque 2025 – étant estimé à 600 millions de livre. Les R1 ont une dotation de 24 spécialistes et doivent utiliser un système ELINT/SIGINT Helix dont les caractéristiques sont confidentielles mais qui est considéré par la RAF comme plus avancé que les systèmes installés sur le RC-135.

Les R1 devaient par exemple disposer d’une capacité de brouillage radar que n’ont pas les RC-135.

UK Yet To Confirm Nimrod SIGINT ReplacementBy: Chris Pocock

August 20, 2009
Aircraft


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.”

UK set to seal Nimrod replacement deal
By Craig Hoyle

The UK Ministry of Defence will sign a contract within the next few weeks to replace its British Aerospace Nimrod R1 electronic intelligence aircraft, having deemed the capability an essential element of its future military equipment inventory.

Once finalised, the deal will advance the planned acquisition of three stored Boeing RC-135 Rivet Joint airframes from the US government. These will be modified for operational use by L-3 Communications Integrated Systems in the USA.

Confirming that a previous proposal to modify BAE Systems' three development examples of the Royal Air Force's new-generation Nimrod MRA4 maritime patrol and surveillance aircraft has been rejected, a senior military source says the Rivet Joint contract will be signed "within weeks".


"We have the approvals, and we have an agreement. We just don't have a contract yet," the source adds.

Long-term activities with the RAF's three Nimrod R1s had appeared to be at risk following the MoD's surprise move in December to accelerate the retirement of its remaining Nimrod MR2 maritime patrol aircraft. Its last Kinloss-based MR2s will stop flying by 31 March, a year sooner than previously planned, and two years before the last of nine replacement MRA4s will be handed over.

The military source says operations with the R1 will be safeguarded until the new Rivet Joint assets become available, partially by using cost savings generated by the MR2 fleet retirement. "There will be no capability gap," the source adds.