When the AS350 AStar was introduced in 1977, its design and manufacture led the industry with extensive use of advanced polycarbonate plastics and epoxy resins. Also known as composite materials, they were used in parts of the airframe and drive system, most notably the three-blade main rotor hub (called a starflex), main rotor blades, and tail rotor blades. Now, more than 30 years later, composite systems are the design of choice.
The AStar has moved through several model upgrades, each time adding power, performance, and reliability. Eurocopter currently offers two versions—the B2 and the more powerful, high-altitude B3. The modern AStar has proven so effective that today more than 750 are in service throughout the United States, most in law enforcement or emergency medical services. With the AStar’s engineering upgrades reaching maturity, American Eurocopter decided that the next frontier is enhancing operations.
With increasing safety of its products as the goal, American Eurocopter began
construction of a state-of-the-art training center in 2005. Included in the plan was an advanced AStar simulator. Based on customer feedback from an advisory board, the goal was to build a highly realistic full-motion helicopter simulator that was affordable—something that had not been achieved in the single-engine helicopter market.
One reason for this is that hovering is difficult for a simulator to replicate. Successful hovering depends on peripheral vision clues and lots of visual detail. This requires a wide viewing area and plenty of computer processing power. Building a full-motion simulator with this level of sophistication has been extremely expensive. And until recently, only a handful of them existed for larger, more expensive airframes such as the Sikorsky S76. It didn’t make economic sense to spend $10 million or $20 million to build a simulator for a single-engine helicopter costing less than $5 million.
In the past few years the price of computer processing power has come down, and less costly electropneumatic motion platforms have replaced expensive hy-draulically activated systems. Leveraging these technologies, American Eurocopter teamed with Indra Sistemas S.A. to design and build the world’s most advanced single-engine helicopter simulator.
The company’s AS350 B2/B3 simulator received FAA Level B certification in December 2010. Paul Osterman, American Eurocopter’s manager of simulation and training, said, “We chose Level B because it strikes the right balance between cost and functionality. Many systems, like the visuals and the motion platform, exceed Level B requirements. At Level B, we substituted our pilot expertise in place of an expensive data collection plan in order to keep the price substantially less than the higher level simulators.” He added, “The finished product handles very similar to the actual helicopter.”
The cockpit simulator before the protective dome was built around it.
The AStar platform was designed from the beginning as a mission simulator. Not only can it train pilots in maneuvers and emergency procedures, but also the entire crew in scenario-based missions. It is currently configured for airborne law enforcement mission training; however, the design allows for future reconfiguration for other missions, such as EMS. To accomplish this, American Eurocopter built the full AStar cockpit and cabin on a Moog motion platform. Good peripheral vision clues come from the simulator’s six high-definition projectors that provide a 220-degree by 80-degree field of view. To achieve a high level of realism, many details were addressed, such as special interior lights that simulate the sun during daylight operations.
The cockpit has all the equipment of police helicopters currently flying law-enforcement missions. It has a fully functioning FLIR Systems Safire III thermal imaging camera with the tactical flight officer hand controller; an AeroComputers moving map display; and a SpectoLab SX-16 slaved searchlight. One interesting feature is the ability to train crews in the airborne use of force. From the rear left seat, a marksman can fire a modified Bushmaster M4 .223-caliber rifle. It is a real weapon that uses CO2 cartridges to simulate recoil and a highly calibrated laser that is read by eight cameras to accurately record each shot. A computer adjusts the simulated bullet’s path for drop and wobble to replicate live firing from a moving helicopter.
Because the visual system extends beyond the doors, a specially designed platform allows access to the cabin. Once seated in the cockpit, the platform retracts for completely unobstructed views—including the lower door areas, which increases lower visual cues. For my flight the simulator was outfitted as the B3 version. In addition to a more powerful engine, the B3 has a collective-mounted throttle. The B2 has the traditional floor-mounted throttle lever next to the collective control. To train B2 customers, the entire assembly is changed to replicate the B2’s system.
Looking forward to flying, I buckled in and Eric King, the simulator tech for the AS350, went through the start procedure with me. With all systems up and running it was time to lift off. We were sitting on Runway 30 at Long Beach Airport in California. Looking out my side window, the visual system’s high resolution was apparent, as I could see the detail in the runway’s asphalt. I refocused my eyes straight ahead and started raising the collective. The simulator lifted off just like an AStar—right skid low.
It didn’t take long to stabilize the hover, and I set it down and picked it up a few times. Some were smooth and some were not, and the simulator did a good job of letting me feel the bad ones. My ego would have preferred that it wasn’t that accurate.
Normal maneuvers in the pattern were authentic and contained no surprises, so we moved on to the more exciting emergency maneuvers. Having done a lot of hydraulic-off landings in the real aircraft, I was looking forward to trying one in the simulator. King gave me a heads up, the warning gong went off, and the red HYD light came on. I still had hydraulic boost from the accumulators, so I slowed to the recommended airspeed of 60 knots and moved the guarded hydraulic switch (located on the collective control) to the Off position. This dumps the accumulators, causing an immediate loss of boost pressure. The cyclic stick immediately moved aft and right, requiring firm forward and left pressure to maintain level flight. I set up for a shallow approach to a run-on landing and the simulator landed just like the real helicopter.
I have never flown a simulator that could replicate an autorotation very well, so that was my next request. From about 1,000 feet agl, I rolled the throttle off and maneuvered the helicopter around, watching rotor rpm and airspeed. That’s the easy part; the challenge is in the flare and touchdown. I started flaring about 60 feet above the runway. Flaring too much made keeping the horizon in view much harder and, for me, made for a sloppy—but realistic—touchdown. My next flare was less aggressive and resulted in a nice auto. I touched down with some forward speed and heard the grinding sound of the skids sliding on the pavement.
The simulator’s realistic flight characteristics, coupled with its mission-training capability, make it a valuable training tool. American Eurocopter believes that using simulators to teach more than flight maneuvers, like aeronautical decision-making and real-life mission training, is the key to lowering accident rates. Much like Eurocopter’s pioneering use of composite materials foresaw the future of helicopter design, American Eurocopter is pioneering the future of helicopter flight training.
Tim McAdams is the director of business development for SKY Helicopters in Dallas. He writes the AOPA Hover Power blog ( blog.aopa.org/helicopter). Photography courtesy American EuroCopter.