Beyond Training
Written by Peter Buxbaum
NETWORKING, DEPLOYABILITY AND OTHER STRATEGIES ALLOW U.S. MILITARY FLIGHT SIMULATORS TO SUPPORT TRAINING AND MISSION REHEARSAL EVENTS.
Over the last few years, developments in flight simulation technology have allowed the U.S. military to work with industry to develop simulation activities that closely approach real-world events. Impressive improvements in simulator visual display systems and the streamlining of the hardware and software required to display high-fidelity graphics has meant that military aviation training organization have been willing to rely more heavily on simulators for more aspects of flight training.
Advances in networking and interoperability have meant that aviators are increasingly able to use simulators for mission rehearsals, going beyond flight training to coordinate with others performing tasks on the same and other aircraft simulators. The development of smaller, transportable simulators has meant that the devices may be deployed to theater, allowing aviators to brush up on their skills closer to the time they take to the air.
“These greatly improved capabilities allow us to accurately simulate and practice various events, such as certain emergency procedures and critical flight regimes that would present an extremely high safety risk if accomplished in the aircraft,” said Will Merkel, simulator requirements officer for the Chief of Naval Air Training (CNATRA), headquartered in Corpus Christi, Texas. “As simulation technology advances and fidelity improves, we are able to consider moving a wider array of critical skills into the simulator.”
The Air Force has already transferred 25 percent of flight training activities on the F-15 to simulators and seeks to achieve a similar number for other aircraft in the foreseeable future. “That is an achievable goal,” said Colonel Jack Franz, the commander of the Air Force’s 677th Aeronautical Systems Group at Wright Patterson Air Force Base in Ohio. “In the future we will be moving toward 50 percent.” For some future air platforms such as the Joint Strike Fighter, that figure might move closer to 100 percent, Franz predicted.
High-fidelity graphics become all the more important to training for close-in missions in urban environments where the military expects to be increasingly operating in the future, Franz noted. Trainers on rotary wing aircraft are increasingly demanding simulation for realistic scenarios such as takeoff and landing in brownout conditions.
The achievement of high-fidelity simulation graphics involves a number of different technological developments and takes a number of different forms depending on the aircraft involved. In the case of helicopter training, for example, the latest simulators “provide better vertical and horizontal fields of view for a better training experience,” said Rick Armstrong, vice president of simulation for Flight- Safety International Inc. “There have been advances in the optics of projectors and mirrors making the simulation more realistic.”
Simulation graphics have made leaps in resolution over the last 10 years, said Jim Scott, FlightSafety’s director of military business development. “It used to be that simulated terrain just showed greens, browns and blues,” he added. “Today the norm is geospecific imagery that has a resolution down to less than a meter.”
Providers of visual databases have also made advances in the types of imagery they are able to supply to the simulation environment. “You can create casts of different characters on the ground and have them moving about,” said Scott. “High-resolution databases allow you to pick out an enemy vehicle on the ground and identify what type of it is from a significant distance.”
In the case of high-speed aircraft simulation, high-resolution functionality also refers to the ability to handle high-rate turns without breaking up or displaying jitter in the visual. Visual databases are increasingly able to handle these requirements, according to Scott. On the horizon are more laser projectors, which provide considerably higher resolution than currently available cathode ray tube images. “But they do it at a penalty of a higher price, and they are bulky,” said Scott. Companies are now working on fourth-generation equipment that will be smaller and more cost-effective, and provide brighter imagery, he added. Laser projectors allow simulators to achieve “eye limited resolution,” the ultimate aim of realism in flight simulators, allowing users to see exactly what they would see with the naked eye if they were sitting in an aircraft cockpit.
MISSION PLANNING
The military’s emerging requirement for flight simulation is for mission training, “which implies much more than pilot training,” noted Steve Baigrie, vice president for engineering and programs at CAE USA.
Mission training “means training all crew members on a particular aircraft platform for their part in the overall mission,” he added. “This mission training needs to include other entities and platforms that may be part of the particular mission. In other words, the primary requirement is for the military to train as they fight.”
“Historically, simulated flight training involved switchology and checklist review,” said Franz. “We want to go toward mission rehearsal, and we are approaching that edge right now. The crews hopefully get to interact with others they will actually deploy with. Pilots hear other real human voices, not a synthetic computer voice and not an instructor playing multiple parts.”
Providing for realistic mission rehearsals, which involve disparate aircrafts operating in a single group, requires networking several different simulators in a common synthetic environment, explained Scott, much as is involved in networking a group of computers. “This involves the ability to do coordinated missions of dissimilar types of aircraft such as helicopters, tankers, transporters and fast movers,” he said. “They are all seeing common threats on the ground and are able to stimulate the threat detection equipment and make it operate as it would as flying into a threat environment.”
The Air Force runs an exercise called Virtual Flag three or four times a year, in which simulators for different aircraft, such as C-17s, F-15s and F-16s, are networked together, Scott noted.
Central to the networking of disparate simulators is the concept of “fair fight,” in which “all the entities in a simulated environment need to have a consistent capability and a correlated view of the outside world,” said Baigrie. “This requires consistent, validated weapons and sensor models, correlation of databases, dynamic terrain, and many other components that make this a challenge in simulation.”
Enabling older simulators to interoperate in this fashion means upgrading their computers with a gateway box that handles the protocols necessary for one simulator to transmit and receive information from other entities. “There is a real-time interface protocol that is embedded in gateway box,” said Scott. “Any tactical aircraft simulator today will have that capability as part of its native environment."
There are various government programs that continue to research improvements in interoperability standards. “CAE is participating in the development of the Army’s Synthetic Environment Core [SE Core] program and leads the development of databases, visual models, and common virtual components to provide a capability aimed at achieving a fair fight,” said Baigrie.
Other related programs include the U.S. Special Operations Command’s Common Environment/Common Database (CE/ CDB), as well as Air Force and Navy programs. CAE led the design and development of the CE/CDB, which is now in operation on two high-performance combat mission simulators, the MH-47G Chinook simulator, which became operational in 2007, and the MH-60L Black Hawk simulator, which was delivered in 2008.
CONCURRENCY AND OTHER CHALLENGES
Because aircraft are constantly being updated, so too must their corresponding simulators. “Fleet aircraft are continually upgraded, modified and acquired that have ever increasing sophistication and complexity,” said CNATRA’s Merkel.
“From our perspective one of the key things is trying to stay concurrent with the aircraft,” said Franz. “When there is a change in software or the aircraft is modified in any way, we need to be able to modify the simulator at the same time so that there will not be any negative training. Concurrency is a must, and simulators are always changing.”
At the same time, simulators, much like aircraft, must be maintained. Simulators contain hydraulics, motion systems, and other mechanical components, noted Armstrong, and sometimes they break down. “FlightSafety maintains crews of maintenance mechanics on a routine basis at operational bases as part of our basic contract support of aviation training systems,” he said.
On the horizon and coming soon are high-fidelity transportable simulators, which can be deployed to theater for training in preparation for a specific mission. “We have been working with the Army to fulfill their strategic needs for simulators with a smaller footprint and which are deployable,” said Scott Watson, director of rotary wing and ground systems simulation and training solutions at Rockwell Collins. The first such Rockwell Collins model, for the UH-60 helicopter, will soon be deployed to Afghanistan.
Transportability means that the simulators are able to be packed in ruggedized shipping containers for overseas deployment or rigged to a railway flatcar or to the back of a large flatbed truck for shorter moves. Deployability refers to the ease of setup and tear down.
“Actual setup can take four people less than eight hours,” said Watson. “The tear down can take four hours or less. The simulator is built with a modular design, so that it can be configured in a matter of hours.”
Transportable devices have been around for some time, noted Watson, but the Rockwell Collins product is the first to exploit the highest fidelity features available, including a full range of visibility and motion simulation. It also includes features requested by pilots in Afghanistan, such as flying at low altitude, landing on slopes, operating in brownout conditions, and experiencing frequent weather and terrain changes.
“The benefit to deployed systems is that aviators can take their training with them,” said Watson. “They can perform rehearsals for mission preparation and maintain the proficiency of their skills.”
“There are, however, some tradeoffs,” noted FlightSafety’s Jim Scott. “You are limited by the package you are enclosed in, in terms of how big the visual can be. Deployed systems also include less motion simulation.
“But the tradeoffs are acceptable,” Scott added, “because you’re not training new pilots; you are not introducing a new student who needs to experience the complete feel of the aircraft. Veteran pilots can work without some of these cues.”
All in all, the U.S. military perceives tremendous advantages from the flight simulators that it has employed. “While acquiring and maintaining modern simulators is expensive,” said Merkel, “the cost relative to operating the training aircraft is frequently a superb investment.”
“The benefits come in the form of reduced flight hours, noise, maintenance, and wear and tear on the aircraft,” added Franz. “This can be a real win for maintaining aging fleets.”
For CNATRA, the recurring and increasing costs of replacement, maintenance, life extension and fuel means it must evaluate which tasks and skills might appropriately be taught, or at least introduced, in the simulator rather than the more expensive aircraft. “As the fleet moves to the next generation of aircraft, both fighters and other attack platforms,” Merkel said, “CNATRA will continue to integrate more advanced simulation activities into our curricula in order to properly feed the fleet with highly skilled new aviators.” ♦