- 13 February 2006
- Reaction score
A French-led effort to develop a stealthy unmanned combat air vehicle is set to move into high gear as engineers begin to prepare detailed definition of the Neuron demonstrator.
For the six partner nations, Neuron is a major attempt to explore what uses a UCAV capability might serve. For industry, it's seen as a vital effort to keep pace with the nearest competitors. Program planners acknowledge that similar U.S. and British undertakings might be further advanced (AW&ST Dec. 11, 2006, p. 35). But with military strategists everywhere still grappling with UCAV requirements, they are confident there's still enough time for Europe to be competitive. In fact, they are already eyeing an extension to the 10-year program to allow more potential uses to be explored.
Major design milestones lie ahead in the coming months. The ýýý400-million ($524-million) undertaking--which kicked off in 2004 and contracted in February 2006--is intended to demonstrate vital technologies for a next-generation combat aircraft (manned or unmanned) and, perhaps more importantly, to show how such a program should be run.
In September, the program passed a first intermediate synthesis review--a milestone in the two-year feasibility phase that's about two-thirds complete. Midyear, managers expect to hold a launch design review, which will permit the project to move into the detailed design phase. Manufacturing is to begin in 2008, with first flight in 2011. Flight tests are expected to last 18 months.
Wind-tunnel testing of various airframe layouts have led to a slight tweak in the configuration and aerodynamic shape (AW&ST June 20, 2005, p. 33). Designers opted for a one-engine (versus two-engine) configuration and shifted from a cranked wing to a single-sweep mold-line. The straight-sweep configuration was deemed to have better controllability and stealth characteristics, although it offers a lower static margin.
High-speed wind-tunnel trials, to begin soon, will allow engineers to refine the current concept, labeled AP781-20, including a compromise between high- and low-speed performance characteristics. A final shape will not be frozen until 2008.
The vehicle is expected to be 9.3 meters (30.5 ft.) long and have a 12.5-meter wingspan--a bit shorter and wider than initially thought. Maximum takeoff weight will be 5,000-6,500 kg. (11,000-14,300 lb.). Top speed is Mach 0.85, and endurance is to be more than 12 hr. Composites will feature heavily in the design.
Neuron will have a fly-by-wire flight control system, four control surfaces and two weapon bays, each sized for a Mk. 82 bomb. It will feature an electro-optic sensor and a line-of-sight data link, but no synthetic aperture radar or radar warning receiver (although there will be provision for supporting a RWR). Avionics, hydraulics and electrical systems will be fully redundant to meet JAR 23 civil airworthiness requirements.
The six industrial partners--Dassault Aviation, Saab, Alenia Aeronautica, EADS CASA, Ruag Aerospace of Switzerland and Hellenic Aerospace Industry--have already assigned about 500 people to Neuron, including 100 or so on the physical design plateau here at Dassault headquarters. More than 1,000 employees will be working on the project by the time production is in full swing.
Some supplier decisions have been made. The aircraft will be powered by a Rolls-Royce/Turbomeca Adour 951 engine, also used by the Hawk trainer. Galileo Avionica will supply the electro-optical infrared sensor, with the aperture placed left of the nose-landing gear. Thales will provide the data link.
Neuron is not an operationally representative system, project officials acknowledge, and its size is only three-quarters the scale of what a future production model would probably require, says program manager Benoit Dussaugey, Dassault's senior vice president for military sales and cooperation. The demonstrator will have a dry wing, limiting range, and feature a host of test equipment to measure vital parameters. Vibration and acoustic noise in the bomb bay, which have caused problems in the past, will be a major area of focus.
Because there will be a big gap between the demonstrator and a future product, an open architecture will be used.
To support the development effort, planners have set up a dozen technology development tracks to mature underlying technologies, Dussaugey says. More than half of those are focused on low observability. Automatic takeoff and landing and airworthiness aspects are also being examined Most of these efforts should be completed in two years, although a few may run on, he says.
Ultimate performance, program planners stress, will be driven by cost and engineering factors. "This will be a true design-to-cost program," says Mats Ohlson, a Saab engineer who is deputy program director. Some important trade-offs have already been made, including the switch to a single-engine configuration. Another was the decision to build only one flight vehicle. "We are taking quite a big risk," Ohlson admits, "but we preferred to put the money into technology." To shave design costs, the nose-landing gear for Neuron will be borrowed from the Mirage 2000 fighter and the main gear from the Falcon 900 business jet. Wings will be removable to cut shipping expenses.
One area where cost control is being stressed is in terms of low observability: Neuron officials hope to break the mold of stealthy platforms being prohibitively expensive.
For now, acoustic signature suppression will not be a top priority. The focus will be on keeping the radar cross section down, with an S-shaped inlet to mask the turbojet's fan, and addressing infrared output, notably by reducing the heat of the engine exhaust. Neuron will also feature a flush data system and probably a novel heat shield, too, although details are being closely guarded.
Aircraft autonomy--another major design driver--will also reflect the design-to-cost approach. Unlike existing UAV programs, which tend to be personnel intensive, Neuron will nominally require only a small ground staff. Controllers will merely provide waypoint updates, allowing the vehicle to replan its route automatically, taking into account programmed threat information. Planners think this approach, which parallels work being undertaken on other UCAV programs, will allow the vehicle to be controlled by just two individuals--and might even permit several vehicles to be handled by the same team.
A third important design objective will be a streamlined development and production setup that can minimize life-cycle costs and delivery delays.
Neuron will be the first combat aircraft in Europe designed, built and supported using the Dassault Systemes/IBM Product Lifecycle Management (PLM) system employed, for instance, for the Boeing 787 and Dassault Falcon 7X business jet. In fact, Neuron will go one step beyond the 7X system, employing PLM for software as well as hardware design. The primary design tool will be Catia V5. The virtual design plateau that permits PLM program partners to manage the database in real time from remote locations is expected to become operational early this year.
The Neuron program will also innovate in the management of intellectual property--one of the greatest sources of potential conflict in cooperative endeavors. "Each partner must feel comfortable it's not creating a new competitor," Ohlson stresses. Any advances made by one partner will be retained by that company, and those made in common will be owned jointly. Specific interfaces between software and hardware elements will help clarify the scope of responsibility. And the details of what a company does behind the interfaces will remain largely proprietary.
There will be no direct feeding of information from UCAV activities run by the partner companies into Neuron.
The management arrangement will also differ markedly from existing military cooperation projects. French armaments agency DGA is supervising Neuron, on behalf of the partner nations. Dassault Aviation bears sole responsibility for managing the program and interfacing with DGA.
Each partner will be responsible for specific project tasks, eliminating the overlap that has bedeviled past cooperative efforts. For example, Saab will handle system design. Dassault will design the air vehicle's fly-by-wire system; Alenia, the smart weapons bay; and CASA, the ground control station. Flight testing will be shared. Trials will start at Istres, near Marseilles, where final assembly will take place. They will then move to Sweden, for low-observability trials and weapons release, before finishing up in Italy. Radar testing at different frequencies will take place in Rennes, France.
What comes after the demonstration flights is anyone's guess. Some participating countries, notably France, are eyeing an eventual follow-on UCAV development program. Others, such as Sweden, are not even sure they would want to arm unmanned aircraft. One of the goals of the test flight campaign will be to help determine future requirements. However, most experts believe a real UCAV is unlikely to be fielded before 2030, which would imply kickoff of development no sooner than 2015.
Therefore, a second flight test demonstration campaign for the 2013-15 period is increasingly envisioned. Other countries could join at this stage (Belgium has already expressed interest). "The focus of such a campaign could extend well beyond low observability, like the U.S. X-45 approach," says Dussaugey. Among potential areas of interest are the use of air-to-air weapons, satellite data links, electronic countermeasures and cooperative flights with Rafale, Gripen or Typhoon fighters.
And some veeery interesting CAD pictures