Flight Simulators as a Training Device by Arthur Gatland

John and I were reminiscing about the good old days when tech crew did touch and goes at the airport - with a real aircraft - as they learned to fly it ready to operate as crew on the aircraft type. As a flight attendant walking across the acres of car parking to get to the terminal, I used to watch the aircraft doing heaps of short circuits as they merely touched down then took off again. A bad landing whilst training was very public! I would have an inane grin on my face as an aircraft emerged from a cloud of blue smoke as it took off yet again.

Imagine the fuel costs and an aircraft removed from the flight schedule just so a few tech crew could be trained on type. No wonder simulators are so important!

We asked our old mate, Arthur - since he’s a Sim instructor - if he would give us a commentary on what an airline simulator might do and what it looks like.

As usual, he delivered big time. Not only did he write us an article, he also got some photos and recorded some video of the simulator going through its paces.

Thanks Arthur! The floor is yours….

Flight simulators have been in use as pilot training devices for over 50 years, but of course they have improved dramatically over that time. Since the 1990s Civil Aviation Authorities have recognised that the realism is such that “zero flight time” (ZFT) simulators may be utilised to train pilots on a new type and issue a type rating without their having flown the real aircraft.

Wee youngster, Arthur, checking out his first sim - at Farmers!

My first flight simulator with a visual display was the Harrier in 1972. Computers were in their infancy and certainly not capable of generating a visual display. This was achieved by creating huge ground models with airfields, towns and terrain, and a camera moved over the model in synch with the aircraft’s “flight” to generate a realistic visual display.

Early Harrier ground model and moving camera to produce a flight simulator visual display.

Zero Flight Time Flight Simulator characteristics:

·  Flight characteristics: The simulator’s flight characteristics must reflect the aircraft exactly, and in fact they use the aircraft’s fly-by-wire computer programming. The flight deck layout must be as close as possible to the aircraft – there are occasionally minor difference depending on aircraft variants, but these must not significantly affect the training outcome.

·  Simulation motion: simulators are mounted on electro-hydraulic struts that produce motion that – to the pilot – feels exactly like real flight. This is achieved with motion that creates the same sensation in the ear’s semi-circular canals as real motion. For example, as an aircraft accelerates on take-off the fluid in the canals moves back, giving a sensation of climbing. The simulator raises its nose to create the same sensation (and similarly lowers the nose on landing under braking.) Turning sensation is achieved by similarly banking then gradually levelling, which tricks the canals to feel like a balanced turn.

Melissa here - check out what the simulator does to simulate braking after landing!

·    Visual displays: Computer generated pictures have improved dramatically over the years. Airport models reflect the local towns and countryside such that pilots can recognise specific familiar buildings. Weather conditions can be varied to simulate rain, fog, snow or ice on the runway and taxiways. If taxiways are selected as wet, you can see aircraft reflection in the ground water. Wet runways have slippery characteristics during landing to provide realistic training. Varying winds, different types of turbulence, a wide range of cloud types can be selected. When flying through rain, selecting the windscreens wipers on improves the visibility appropriately!

·   Aircraft faults:  Naturally all likely aircraft faults can be selected by the instructor, providing  accurate noise, flight characteristics etc applicable to the failure.  This includes external factors such as other aircraft producing a TCAS alert (collision avoidance commands), bird strikes, windshear, icing etc. Various types of engine failure can be selected by the instructors, giving vibration and changes in flight path and performance capability appropriate to the failure.

· Unusual attitudes: Pilots can be given valuable training in how to recover from extreme attitudes, such as high nose, noise low, severe overbank, overspeed and stall situations. There are no limits to the attitudes (hence the ability to do unofficial “fun” exercises such as aerobatics!)

·   For interest I thought that our B787 flight simulator slightly exaggerated the level or aerodynamic buffet in an Overspeed approaching transonic speeds, so I decided purely for interest to try and go supersonic just to see if the simulator accurately reflected the change in Centre of Pressure (which used to be known as Mach tuck) and other transonic characteristics. I could only achieve M0.93 by pushing full forward with full thrust, so I rolled inverted and pulled the nose fully vertical. The speed increased steadily to Mach 0.999 but was not programmed to indicate more than that! Recovery was easy but there was no indication of Centre of Pressure change. Note: simulator manufacturers do not guarantee the accuracy of flight characteristics in a deep stall or massive overspeed, since this information is not available from the aircraft manufacturers (the aircraft are not tested in those extreme parts of the flight envelopes.)

·    Safety: pilots and instructors are briefed to wear a seat belt / seat harness whenever simulator motion is on, and at each pilot and instructor station there are emergency motion cutoff switches.

·  Access: pilots enter the simulator via a bridge, which is retracted when the motion is selected on. In the event that an evacuation is needed – for example a building fire – and the bridge fails, there is an emergency rope ladder to allow evacuation!

Entrance to the Sim is via a bridge that raises once the Sim is active

General Information:

Flight simulators provide outstanding training in all normal and extreme emergency situations without putting any aircraft (or pilots) at risk. They have a high degree of realism and fidelity, and this is checked on a regular basis to allow continued CAA Approvals.

All pilots are under regular training and are required to demonstrated continued proficiency every 6 months throughout their flying career.

A modern flight simulator costs around USD $30 million, but this is a good investment which enables all training and proficiency checks to be done using a training device and not the real aircraft (which are more expensive to operate and are required for full-time commercial services.) Some airlines hire simulators from other operators or training centres rather than buy their own, but this is dependant on airline fleet size, geographical location and balance of costs.

Air New Zealand has one or even two flight simulators for every type it operates. They operate in back-to-back 4-hour slots starting from 0600, 1000, 1400, 1800 and even 2200 during times of high training workload. One slot is reserved routinely for Maintenance (and of course for defect rectification as required.)

Pilots undergo a 1-hour briefing, 4 hours flight simulation, and a 30-minute debrief (or as required.)

Debriefs are a critical part of the outcome, and pilots are encouraged to self-critique and – with instructor guidance – go away with techniques for self-improvement. All simulator details are recorded on video, with recordings of instrument displays, head-up display etc to allow careful analysis of any learning points. These are recordings are erased after the debrief.

No-one ever leaves the simulator without saying “that was great, I really learned something there!”