In September, Boeing and Saab revealed the design that the team will propose for the US Air Force’s (USAF’s) T-X competition: an all-new aircraft designed specifically for the programme featuring cutting-edge technologies, tools and manufacturing processes.
Two aircraft were rolled out at the unveiling ceremony, showing a single engine (General Electric F404 engine), twin-tailed aircraft with advanced glass cockpit and embedded training. Few hard and fast details have been released about its capabilities by the team, but it is being hailed as an aircraft designed to evolve as technologies, missions and training needs change, while being more affordable and flexible than older, existing aircraft, including the air force’s ageing T-38 that the T-X programme is working to replace.
The competition heats up
Other designs have been unveiled by three teams: a team led by Raytheon including Leonardo, Honeywell Aerospace and CAE; a Lockheed Martin-Korea Aerospace Industries (KAI) partnership, and a consortium headed by Northrop Grumman, including BAE Systems and L-3 Link Simulation & Training.
The Raytheon team’s bid is the T-100 integrated air training system: a fully integrated flying and ground-based training system that can download training missions from frontline fighters, and embed training simulation with live virtual blended constructive capability. The aircraft is an advanced variant of the M-346, a next-generation twin-engine aircraft (powered by two F124 engines) with advanced cockpit (modern head-up display, customisable large-area display and fully-integrated helmet mounted display) and avionics emulators. Ground-based training and simulation will be powered by CAE USA.
The Lockheed Martin offering is the T-50A aircraft, building on the heritage of its T-50, more than 150 of which are currently in service with military forces. The system is designed to mimic the capabilities of the fifth-generation aircraft students will be training to fly, with advanced aerodynamic performance, digital flight controls/fly-by-wire, with next-generation air traffic management systems, all operating from an anthropometrically designed fifth-generation cockpit.
The T-50A’s configuration is based on the FA-50 currently in production for the South Korean military. This aircraft incorporates air-to-air and air-to-ground weapons, along with an avionics suite that contains an electronic warfare suite, a multi-mode radar and an advanced data-link.
The T-50A is being billed by the team as a low-risk, ready now solution. The aircraft undertook its initial flight test in June 2016, and the final assembly and check-out site is under construction in Greenville, South Carolina.
Less is known about the solution that the Northrop Grumman team is set to offer. No official word has been given by company executives on the form the system will take, but it will be a purpose-built, newly designed aircraft – a so-called ‘clean sheet’ design as with the Lockheed Martin offering. Images released on social media in August showed what company officials have since confirmed is the team’s prototype aircraft undertaking high-speed taxi tests in California. The aircraft, as with the Northrop-developed T-38, is a twin-engine design with large vertical tail.
Closing capability gaps
The USAF plans to acquire 350 T-X trainers to replace 431 T-38s in autumn 2017. The aircraft’s initial operational capability is set for the end of 2023, at which point the new aircraft will take over the air force’s training needs for undergraduate pilot and introduction to fighter fundamentals.
Ultimately the air force is looking to meet its fighter pilot training requirements more effectively and affordably while reducing inefficiencies that have crept into the T-38 Talon programme. According to Brigadier General Dawn Dunlop, the director of plans, programs and requirements at Air Education and Training Command (AETC), the T-38 is “no longer a practical trainer to prepare air force pilots for newer, more advanced aircraft” such as the F-22 and F-35. At present twelve of 18 advanced pilot training tasks cannot be completed with the T-38, meaning the AETC has to rely on fighter and bomber formal training units to complete the training at a much greater cost.
Additionally, cockpit and sensor technologies have moved on in a fundamental way since the T-38 entered service with the US military in the 1960s. While upgrades have installed glass cockpits in the T-38, the programme is now seriously struggling with inabilities to upgrade the aircraft’s performance and simulated sensor capabilities to meet the needs of pilots training for fourth and fifth generation jets and teach the critical skills required. Furthermore, the T-38’s availability has been below the 75%requirement since 2011, meaning that on the whole, the aircraft is not mission-capable.
Narrowing the field
The road to upgrading the USAF’s fast jet training capabilities is a winding one, and the air force initially released draft requirements for the replacement aircraft in 2012. These requirements have undergone a number of iterations and refinements – closely involving industry collaboration to shape a more capable and affordable solution – with official requirements released in March 2016. Of the more than 100 requirements listed, the three key performance characteristics that will close training gaps in current capabilities are sustained G, simulator visual acuity and performance, and aircraft sustainment.
The sustained G-specific parameters have been clarified by the air force, as a minimum “threshold” requirement of 6.5G and the desired “objective” requirement of 7.5G. The understanding is that these parameters, accompanied by the other T-X requirements, will offer the necessary performance capabilities to train air force pilots well into the future.
With respect to manoeuvrability, AETC has clarified that the T-X must maintain the required load factor for a minimum of 140 degrees in a descending 180-degree turn. Initiated at or above 15,000ft pressure altitude, at or below 0.9 Mach, and at or above 80%fuel weight, the aircraft’s flight path angle during this manoeuvre can be no lower than 15 degrees nose low while losing no more than 2,000ft of vertical altitude and 10%of the initial airspeed.
The embedded training element is also of note, requiring synthetic sensors and data link capabilities that will ensure the T-X aircraft very closely approximates the real platform.
The final request for proposal is expected to be published before the end of 2016; what will follow remains to be seen, but with the T-X programme possibly the most prestigious and lucrative fast jet training programme underway, the stakes for all bidders are high and it’s likely to be an exciting ride.