FlightSafety’s new UPRT course offers training that can help pilots deal with loss of control, the accident category with the greatest number of fatalities in business and commercial aviation and also one of the NTSB’s “most wanted” safety improvements. The FlightSafety UPRT program is conducted in a Gulfstream G550 simulator, the first qualified by the FAA with an aerodynamic model that can replicate out-of-the-normal envelope maneuvers.
I was the fourth non-FlightSafety pilot to attend the company’s G550 UPRT class, which was taught by Dann Runik, FlightSafety executive director of advanced training programs. Runik was careful to point out that this course is designed specifically for Gulfstream pilots and isn’t necessarily transferrable to other airplane types. The exercises we practiced replicated many of the notorious loss-of-control accidents of the past 30 years, none of which occurred in Gulfstream jets.
The training is specific to large-cabin Gulfstreams because the G550 simulator was reprogrammed to reflect actual Gulfstream flight-test data. Full-flight simulators are typically not aerodynamically modeled outside the normal flight envelope and cannot be used to replicate full stalls or for UPRT.
To reprogram the G550 simulator, Runik worked closely with Gulfstream test pilots, flying the simulator and comparing its behavior to the test pilots’ G550 flight-test reports. “I wanted to make sure it matched the reports,” he said. “Sometimes it didn’t,” and the programmers would have to tweak the code to make sure the simulation matched the real airplane. The entire process took nearly five months. “Without Gulfstream, we could not have done it,” he said.
According to FlightSafety, the aerodynamic models “are based on actual aircraft flight-test information, wind tunnel testing and analytical data, including low speeds that replicate deep aerodynamic stalls and extreme high speeds beyond Vmo and Mmo.” The G550 simulator is the first to be “qualified by the FAA for UPRT under AFS-205, FSTD Guidance Bulletin 11-05.” Next up will be the G450 and G650, Runik said, and other business jet OEMs have expressed interest in sharing their data so FlightSafety can model their jets’ beyond-the-normal envelope behavior.
Besides the safety benefits, this effort is also intended to meet new Part 60 training regulations expected to affect airlines and charter operators in about five years, according to Runik.
The G550 UPRT is a one-day course currently taught at FlightSafety’s learning center in Savannah, Ga. The day begins with a morning of ground school covering aerodynamics and the kinds of accident that UPRT is designed to prevent.
The aerodynamics portion goes over material that many pilots have probably seen before, but Runik’s explanation of the subsonic, transonic and supersonic regimes and how they affect the airplane and more specifically the flight controls made these subjects far more understandable for me than they were during my previous attempts to learn them.
Some of the key points included a discussion of angle of attack and how to derive it by looking at the G550’s head-up display and noting the angle between the boresight and flight-path vector; how supersonic shockwaves affect the flight controls even at transonic speeds; a detailed discussion of the V-N diagram (velocity versus load factor); the importance of unloading the wings during any upset and how that improves aileron effectiveness and eliminates the possibility of stalling; stability and control; and finally the recovery technique.
In the Sim
While I was eager to get into the simulator, the ground school was crucial and did a great job preparing me for the UPRT session. Normally, pilots will sign up for the class in pairs, with each pilot flying for a couple of hours then switching seats and observing and acting as copilot. Since I was by myself, Tom Emmolo, director of advanced training programs, flew right seat. Emmolo was training to become a G550 UPRT instructor at the time of my visit.
The UPRT recovery technique is straightforward and always the same: push, roll to place the lift vector perpendicular to the horizon, pull (at maximum g loading if below maneuvering speed) and manage power as needed.
“The quickest way to recover from a stall,” Runik explained, “is to unload the wings first, then return to wings level.” It is important to unload the wings because an aileron on a stalled wing is ineffective, and if one wing is stalled and the other isn’t, only one aileron can help return the wings to level. By reducing the angle of attack on the wings, the ailerons are again usable to help the return to wings level.
In the simulator, Runik first had me practice moving the ailerons from stop to stop, to get used to the occasionally aggressive moves I would have to make in some of the upsets. Then he had me practice some unusual attitudes to get used to the way the world looks on the visual display in other than normal flying.
We moved into clean and dirty stalls and tried to hold the yoke aft to get the G550 to do a “falling leaf,” where it would roll from left to right while stalled. The first time we tried this, it fell off on one wing, but it worked the second time, illustrating how accurately the aerodynamics are modeled because this is similar to the unpredictability of the real airplane’s stall characteristics, according to Runik.
With the simulator at 48,000 feet, Runik instructed me to lower the nose steadily at three degrees per second to 20 degrees nose down with maximum power set. As the G550 accelerated, the shockwave produced on the nose of the airplane blocked the pitot tubes, giving us erratic airspeed indications, but they settled down as we picked up more speed. I could feel a subtle buzz in the ailerons, and the loud cockpit noise was distracting. With 400+ kias showing on the airspeed indicator and a sink rate of more than 10,000 fpm, I tried turning left and right.
The high speed makes the flight controls extremely heavy, but the point is to learn that the airplane can still be maneuvered, even though it feels worse than a modern car with power steering failure. I had to pull back hard on the yoke and use electric trim to get the nose back up, but carefully, too, to avoid pulling too many g.
The next part of the training was the best, replicating the precursors to actual accidents. While we tried mirroring some of the worst loss-of-control accidents, I’m giving scant detail here because this is the heart of the training and it really needs to be experienced for it to sink in. The FAA recommends that instructors not announce the upcoming scenario and let the pilot experience the full startle factor in the simulator.
This is a contentious issue in the training world, and some believe that the startle factor can be achieved only in a real aircraft. Runik pointed out, “It’s impossible to have a startle factor [in the aircraft],” because there is too high a risk of breaking the aircraft if the pilot reacts the wrong way.
In the simulator, not briefing the pilot on what to expect is easy, and the worst that can happen is that the instructor has to reset the computer. Not only can Runik allow pilots to crash into the ground in the simulator, but he can also put pilots into a dire situation close to the ground–suicidal in a real airplane.
“What kills pilots is when they see that ground rush,” he explained. The natural reaction in that case is to pull back on the yoke and the result is always a stall. Pilots must be taught to fight that reaction, and being able to train to do that close to the ground is a huge benefit of this simulation. “With the high-fidelity visuals, that ground rush is the real deal,” he said.
I will describe two scenarios briefly, but first let me admit that I crashed the simulator more than once. In the replication of the USAir Flight 427 crash, where the rudder went hard over by itself, I had to react almost instantly by pushing the yoke forward to maintain some semblance of control.
Even though I flew this scenario twice, I was unable to land on the runway with the rudder fully deflected. We might have survived; in any case this was a better outcome than a high-speed inverted dive into the ground, and the recovery technique paid off, although I had to be extremely careful not to induce a secondary stall.
Particularly interesting was a low-altitude stall inspired by the Asiana Flight 214 accident in San Francisco, where the pilots failed to add thrust after the auto-throttle retarded power and then stalled the Boeing 777. In this scenario, which didn’t exactly replicate Flight 214, we flew a left downwind leg and at my request my copilot set a vertical mode in the flight guidance panel. This caused the auto-throttles to move the power to idle, but I wasn’t supposed to be aware of this and continued turning base and pulling up the nose until the G550 stalled at about 720 feet agl.
Trying to help, my copilot then pulled on the yoke, and I had to take over, ask him to let go of the controls and try to recover from the stall using the UPRT technique. This was a situation where I had to be quick and aggressive with the controls, and it took me four tries before I could recover.
In some of the attempts I caused a secondary stall, probably because I could see the ground rushing up at us, and it took not only a hard push to unload the wings but a careful pull after leveling the wings to avoid stalling again. Of course, a hefty application of power was also necessary. In my successful completion of this exercise, the G550 recovered with 200 feet to spare.
I thought the G550 UPRT was enormously helpful, not only strengthening my understanding of basic jet aerodynamics and performance, but also adding a new measure of confidence to my flying skills, backed up by some new muscle memories that I hope will never atrophy. I have done upset training before in airplanes, from an Extra 300 aerobatic single to an Impala single-engine jet, but none of that was anywhere near the ground. Trying to keep the G550 sim from crashing after a low-altitude stall was as real as it gets.
(Matt Thurber - AINOnline News)
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