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A320 FFS LOFT Session

The Flying Engineer was part of a 4 hour LOFT session on a Full Flight A320 Simulator at CAE, Bangalore. The LOFT session was for two line pilots of Kingfisher Airlines, and brought out very clearly the training that is imparted today in the simulators. If training or systems are better today, it is because of the accidents and incidents of the past. By identifying the specifics in the simulator session with accidents and incidents in the past, the relevance of the training is clearly brought out in this first hand experience.

Three Full Flight Simulators (FFS) at CAE, Bangalore: Left to Right, A320, B737-800, A320

Not too far from the international airport, Captain Vimal Roy, DGM Business Development for Ground Schooland Simulators, Kingfisher Airlines, strode into a briefing room at the CAE simulator establishment in Bangalore. Being an examiner on the Airbus A320 family of aircraft, he looked purposefully at Captain Payal Pasricha, and First Officer Neeraj Thapar for whom he would be taking a line oriented flight training (LOFT) and pilot proficiency check (PPC) session that day.

Training is an integral part of ensuring a pilot’s competency in handling a broad spectrum of challenging situations. It also ensures that the pilot follows procedures that maximize the safety of all on board, in both normal and abnormal flight conditions. Decades back, the only means of satisfactorily training crew, both experienced and inexperienced; commander or first officer, was to put them in the real aircraft sans passengers, and practice challenging situations that may be faced by anyone, any day. There are two problems, however. One is the cost involved in conducting such training, with a real aircraft, fees, and fuel. The other is the limits within which everything has to be practiced: Under no circumstances can pilots simulate an all engine failure or practice a belly landing in the event of a landing gear failure. Pilots were instructed, and it stopped at that.

The other alternative is to train in approved flight simulators. Simulators are training devices which create an immersive environment for the pilots being trained, with the ability to simulate various scenarios as decided by an instructor. With the advent of immense computing power and display technology, the world of simulation has changed.

Good displays take up immense processing power, and that became available years back. The current highest level of simulation fidelity offered is Level D, which is characterized by extremely realistic visuals. The other standard features of full flight simulators include the simulation of flight forces (within a limit), realistic audio, and a fully functional setup that exactly resembles the cockpit of the aircraft it is designed for.

And the advantage of simulators is two fold. Pilots can afford to make mistakes, and try what could otherwise not be risked. This could include even a crash, without damaging equipment or taking away lives. The second advantage, of course to the ones footing the training bill, is the cost. For level D simulators, the cost of a simulator session, when compared with that of a similar session in a real aircraft, can go to as low as 1:40. This is what makes airlines happy, while ensuring the standards of their crew. In the airline business, it all comes down to the dollar.

Captain Vimal Roy briefing Capt Neeraj and Captain Payal before the session.

“Delhi to Mumbai” broke the silence. Roy began scribbling on the board conditions in which the pilots were to operate an almost normal flight from Delhi’s Indira Gandhi International to Mumbai’s Chhatrapati Shivaji International airport. Seated assertively, he took up various situations that a crew could encounter on a normal flight, such a nose wheel steering fault, secondary control surface malfunction, or a low visibility take off. Apart from checking for the corrective actions that the pilots are expected to take when situations were encountered, technical or operational, emphasis was laid on decision making, as evidenced by one such scenario.

An aircraft normally does not start its engines on the bay, but begins the start during push back. A third smaller engine on the aircraft, for purposes of electric, and pneumatic power only, called the APU, or auxiliary power unit, provides the necessary pneumatic pressure to start the engines. If during the starting process, the APU itself fails, no power plant on the aircraft is available, with both engines (in case of the twin engine Airbus A320) and the APU dead. Only few systems are left active, feeding electric power off the battery. In such a situation, the aircraft is left on the taxiway, with all power plants inactive. The two pilots were asked about what they would do.

Vimal Roy throwing challenging, brain racking scenarios.

“Decision making, this is exactly what I’m talking about”, emphasized Roy, “Would you keep the aircraft on the taxiway, call for the Ground Power Unit, which would take another 5 minutes, block the taxiway for that time, and then get ready after another 5 minutes? Or would you prefer to get pulled back into the bay, freeing the taxiway for other aircraft, and starting the engines on the bay?” Sound sense resounded in the second option, which was accepted by the other two. And if the second option, the preferred one, is executed, only one engine can be started in bay, before the aircraft is pushed back onto the taxiway and the second engine started. The QRH (Quick Reference Handbook) states that the engine started must increase its compressor RPM (N2) before air can be bled off to start the other engine. “It is your duty to tell the ground crew the distance to be kept off, and vehicles to be checked for, keeping in mind the jet blast from the engine”

Even with more than 10,000 flying hours in her books, Payal had something to refresh her training with, as is the case with every professional in every field. The challenge today is the increasing complexity and automation in the aircraft, which, although designed to make flying safer with a decreased workload on the crew, demands a deeper understanding of the systems, and the interaction of one system with another. Its akin to a complex web, thanks to the Airbus A320 family (Airbus A318/A319/A320/A321), A340 family (Airbus A330/ A340) and the A380 being one of the most complex and sophisticated airliners in widespread use. “We get an opportunity to practice stuff which you wouldn’t want to or be able to do in the aircraft”, admits Payal.

Practice is the keyword in proficiency. Two simulator recurrencies are held each year, for every flight crew member. As Payal and Neeraj climbed up into the CAE Airbus A320 simulator resting on its six hydraulic cylinders, they knew that they would be tested in this LOFT (Line Oriented Flight Training) and PPC (Pilot Proficiency Check) session.

Actual flight deck realism, coupled with a powerful instructor station can make an FFS an ideal training aid.

The A320 sim’s insides were identical to that of a real Airbus A320. The total A320 cockpit was duplicated to the millimeter, and every knob and switch was identical in its look, feel and functionality to the real airbus A320. After all, it’s a full flight simulator, coming from a leading manufacturer, CAE.

The only additions were the instructor panels. Few switches, and touch screens attached to the instructor’s seat, which displayed innumerable menus for scenario simulation. From weather to system malfunctions, from dangerously close aircraft to bird strikes, name any known abnormality or condition, and it will be there to simulate. But it’s totally up to the instructor to recreate a pressure cooker scenario, where the true abilities of the crew are brought out.

According toRoy, “only 30% of an untrained crew’s abilities are available in a challenging situation”. And what instructors like Roy strive to do is to raise the bar, by eliminating waste: both time and effort.

The motion in the simulator was activated. Six hydraulic cylinders move a Stewart platform, which is a motion base to provide cues of real motion. The importance of this lies in complementing the visual cues as seen from inside the simulator deck. Such platforms can provide about +/- 35 degrees of pitch, roll and yaw, and around a meter of the three linear movements heave, sway and surge.

The session began by virtually placing the crew at one of the gates at Delhi IGI. After all the necessary pre-start checks, the crew initiated the push back, attempting to start the engines. The APU failed during start, and Payal requested for the aircraft to be towed back to the bay. In the meanwhile, Neeraj attempted to contact Kingfisher Dispatch on VHF radio #2 informing them of their return to bay due to the failed start. The problem is, VHF #2 does not operate on the battery. In situations like these, system knowledge is very important. And that’s what a simulator session is all about: to identify those aspects which the crew undergoing the session need to refresh or upgrade, and provide them with the best opportunity to learn, correct and augment their knowledge about the aircraft systems.

Capt. Vimal Roy at the instructor station.

Finally, on engine start, the aircraft taxied out to the runway. Visibility was poor: sufficient for a take off, but below the minimum for a landing. In such a case, take off alternates have to be filed, just in case a failure on take off requires the aircraft to get into the air and land as soon as possible. Airports within one hour flying time were selected:Lucknowand Jaipur, and the take off can be legal only when these take off alternates have a Runway Visual Range (RVR) in excess of the minima for landing.

Take off power was applied, and on lift off, the weather radar sensed and reported a wind shear warning. A wind shear is a difference in wind speed or direction between two wind currents in the atmosphere, over a relatively short distance. These wind speed variations in excess of 45kts in the horizontal direction can have disastrous implications on an aircraft, with the possibility of a stall. Vertical components of the wind difference greater than 500 feet/min can also be detrimental to flight safety especially on take off and landing. The aircraft guidance computers are blind to a wind shear, prompting the pilots to follow the desired, normal flight path which would be fatal. However, ignoring these commands, in favour of the procedure, which is to apply full take off power and climb out to clear the sheared areas as soon as possible, is the training imparted, and the decision making expected.

“Threat, and Error, if unresolved and poorly managed, may lead to an incident”, saysRoy, pretty grimly. During a wind shear exercise, pilots are trained to talk less, follow procedures, and task share effectively. “One flies, while the other pilot ensures that the plane does not get back into the dangerous situation”.

On Feb 14th, 1990, Indian Airlines IC 605, operated by an Airbus A320, was coming in to Bangalore, in good weather, for a landing. An error, which was made by the pilot, had disastrous implications to the flight, just because it went unresolved. The commander, who was the pilot flying had requested the check pilot, who was pilot monitoring, to set 700 feet per minute descent on the vertical speed, but instead, erroneously, the pilot monitoring set 700ft in the altitude window. The aircraft had entered into an open descent, commanding idle thrust, instead of maintaining the aircraft approach speed of 132 kts. As the speed washed out, the aircraft descended rapidly, and the error was recognized, albeit too late, resulting in the 4th worst accident involving an A320, globally.

“Read the FMA (flight mode annunciators, which are cockpit indications of the mode the flight guidance computers are in)! It is very important you pay attention to what the FMA reads, otherwise this aircraft will take you for a ride”, emphasizedRoyto the two pilots, during the session. In the case of IC605, the pilots did not see what the aircraft was telling them, that the thrust was not being commanded as thought by the pilots. Had they seen what the computers were showing, the incident could have been avoided.

“It’s always easy to sit back in a relaxed environment and think of what could have been done. But when placed in a pressing situation, the crew’s actual response and performance may not be what it should be”

And to tackle this issue of under-performing, instructors tell their crew what needs to be done. “When reading your QRH, or your FCOM, focus on only what’s relevant. There is a symbology that if followed, will cut down on unwanted talk. Unwanted talk leads to a lousy phase in flight, which ultimately lands up confusing the other pilot”

And this was brought out classically whenRoysimulated a TAT (true Air Temperature) probe fault, with an anti-ice fault on the pitot tube. As a result, the true airspeed readings went off the mark, leading to an airspeed disagreement between the captain’s and the first officer’s speed readings. The crew pulled out the necessary documents which highlight and suggest the corrective actions. But in the excitement of the situation, a simple procedure was overlooked: cross checking instruments with the standby airspeed indicator on the ISIS (Integrated Standby Instrument System). Minutes were spent reading documentation that was unnecessary. And the sim session is more than just streamlining this process. Says Roy, “It’s about sequencing your tasks in the cockpit”.

But sometimes, this sequence can easily be broken by interruptions, either by calls from the cabin crew, or from the Air Traffic Controller over the radio. In the case of IC 605, just when the commander had requested the check pilot to set 6,000ft in the altitude window, the latter was interrupted by ATC, in a conversation lasting over 18 seconds.

“605, report short finals”

“We are short finals”

“Roger, cleared to land”

“Cleared to land, 605”

Immediately thereafter, the commander called for the landing checks, and the otherwise life-saving 6,000ft was missed.

Such interruptions also concernRoy. In the scenarios simulated, he continually kept disturbing the crew with calls from the cabin and air traffic control. The two handled the situation very well, without losing their flow of thoughts. ButRoymade a point : it could be the crucial and fatal disturbance. As was the case with British Midland flight 092. Severe vibration on engine #1 was mistaken for a fault on engine #2, and accidentally the latter was shut down. In the final moments of that flight, just as the commander decided to restart #2 and check if the problem was actually from that engine, an instruction from ATC distracted him from an action that could have saved the day. Sadly, at 2.4Nm from the runway, the damaged #1 engine lost power, and the aircraft stalled, resulting in the first ever loss of a Boeing 737-400, in the January of 1989

But it’s not always a damaged engine that results in the loss of engine power. Sometimes, the source of the problem is the source itself: fuel. Running out of fuel is something no pilot wants to see his aircraft experiencing. But the inevitable does pop up.

Roy had given the pilots 3 tonnes of fuel, and had placed them near Mumbai for a landing into Chhatrapati Shivaji International. The weather was bad: visibility was poor. In executing the ILS approach, they reached their minima: the minimum altitude below which, if the runway lights or runway is not visible, the crew must execute a missed approach. Take Off and Go Around (TOGA) power was applied, and they climbed out. Here was another classical example of decision making: to hold over Mumbai and wait for the weather to clear, or divert to another airport? And to complicate matters, Roy simulated a slat lock: the leading edge flaps on the wings stuck at their fully extended position.

15th November, 1993. An Airbus A300 operated by Indian Airlines as IC440, was on a routine Chennai –Hyderabad flight. Low visibility atHyderabad forced the crew to execute a missed approach. They then entered a holding pattern above Hyderabad, during which discovered that the visibility in nearby air force fields were also low. To complicate matters, the flaps could not be retracted : they were stuck in their extended position.

The commander, with 17,344 hours of flying experience, then decided to fly back to Chennai. Due to the extended flaps, the plane had to be flown at a slower speed and at a lower cruise altitude. The drag on the aircraft was higher than normal for a cruise, leading to a higher fuel burn. In course of their flight, the commander realized that a fuel shortage was imminent, and decided to land at Tirupati. However, fuel was insufficient even to reach Tirupati, and the aircraft executed a forced landing in an open paddy field about 14 NM fromTirupatiAirport. The aircraft was badly damaged and written off, but providence and good piloting allowed all 250 on board to exit the aircraft without any major injuries.

The flying crew in the simulator was vectored to 20NM east of Mumbai. The rate of fuel burn alarmed them: their fuel was getting dangerously low. To them, nearby Pune was not viable, considering their high drag configuration. Decisions are tough to make, and this is when the pressure builds on the crew. Finally, the decision was made to land at Mumbai, despite the poor visibility. Running out of fuel over a mountainous terrain was something they didn’t want to live through. And so the landing was performed, although hard, in extremely poor visibility: allowed only by regulations which permit an aircraft in emergency to land in visibility below the minimum.

In pressing situations, logic fogs out like the visibility outside the window.Roycalmly reviewed the situation, bringing to their notice their position at the time of decision, and the flying distance of about 66NM from Mumbai to Pune. “You were already 20 NM east of Mumbai. It’s just another 40NM or so to Pune. And as per QRH, take the fuel burn of a slats extended A320 to be 1.6 times that at clean configured one”. On the calm review of few fuel calculations, the light was seen: flying to Pune was absolutely feasible, washing away thoughts of running over fuel over the mountain-riddled part of the country.

20th January, 1992. Air Inter flight 148, being operated by an Airbus A320, was descending into Strasbourg-Entzheim airport inFrance. The crew was cleared for a VOR/DME approach for runway 26, which they began, at 5000ft, at waypoint ANDLO, as per the charts. After ANDLO, the approach profile calls for a 3.3° glide slope, something that the Airbus A320 supports in its TRK/FPA (Track / Flight Path Angle) mode. However, guidance was in the HDG/ V/S (Heading / Vertical Speed) mode. On entering -3.3 into the Flight Control Unit, the crew mistakenly assumed that the aircraft would now guide descent at -3.3° (flight path angle, which corresponds to 800ft/min rate of descent at approach speed), while the aircraft now descended at 3,300 ft/min (vertical speed). Ahead, in clouds, were theVosges mountains. Just 3 NM after commencing descent, the aircraft struck trees and impacted a 2710 ft high ridge, killing 87 of the 96 occupants on board.

One system which could have prevented the crash is the GPWS, or Ground Proximity Warning System. Nowadays, all aircraft have at least a GPWS, with most airliners fitted with an EGPWS (Enhanced Ground Proximity Warning System). With an EGPWS, the crew gets alerted to the presence of terrain ahead of the aircraft, which may be in its flight path.Roywanted the crew to react to an EGPWS, and so asked them to nose dive the aircraft towards a hill near Mumbai, with thrust set to idle. Soon, the EGPWS sounded “TERRAIN, TERRAIN”, a terrain map automatically appeared on the Navigation Display, and the crew could “see” the terrain ahead even without looking outside.Royasked the crew to pull up without touching the thrust levers to demonstrate the enhanced safety features and the protections available on the Airbus.

Normal pilot knee-jerk reaction is to apply full power when climbing out, smoothly pitch up to about 20 degrees or till the stall stick-shaker sets in, monitor airspeed and then maintain climb at near stick-shaker speed. In an Airbus A320, this is not required. The aircraft went nose up by about 30°, and the airspeed started to wash out. Any non fly-by-wire safety limited aircraft would have stalled at low speeds, but in the Airbus fly-by–wire family, Alpha Floor protection, or protection against stall, sets in automatically. Below a specific speed and above a certain angle of attack (α – alpha, which varies with the aircraft weight, configuration and manoeuvre), labelled as Vα PROT, the thrust is automatically commanded to full. In this way, the pilot needs only to pull back on the flight stick, and the aircraft would automatically apply full thrust and climb out. The Airbus Fly By Wire aircraft, with their hard protections and on board computers, enable the aircraft to make use of the available energy most efficiently, to gain altitude. The angle of attack immediately increases to α-max, which produces maximum climb performance, while at the same time, by maintaining it, eliminates the risk of staling. Studies have shown that in Airbus FBW aircraft, terrain can be cleared with a higher chance and greater repeatability than with conventional aircraft. This is because, in conventional aircraft, altitude gain is slower due to the absence of the precision that is seen in fly by wire aircraft. But for this safety margin to be realised, pilots need to be trained on how to react keeping in mind Airbus’s philosophy.

Every aircraft is designed with a particular philosophy. Understanding and abiding by that philosophy will ensure that the aircraft is used efficiently and effectively, while eliminating room for errors and misconceptions to creep in.

For all the technology and systems on board, not a single one is capable of forewarning a bird strike. When on the approach to Mumbai in good visibility,Roymade some birds strike one of the engines. The severity of a bird strike depends on the nature of such a strike: Bird ingestion into the engines more often than not results in the almost complete loss of power from that engine. Other damages to the aircraft could include nose cone damage and structural damage.

15th Jan, 2009. An Airbus A320 operated by US Airways took off fromNew York’s La Guardia Airport, on a routine flight to Charlotte-Douglas International Airport,North Carolina. On take off, the crew spotted a formation of Canadian Geese. Before they could react to it, the windscreen turned dark brown with blood, several loud “thuds” were heard, and the smell of burning birds filled the cockpit. Both engines lost power, when the aircraft was just 3,200ft in the air. Good piloting by the calm captain ensured a smooth landing in theHudson, with no injuries.

Exactly a year to that incident, to the hour, the crew in the simulator handled the one-engine out scenario with ease. A smooth landing on Runway 27 of Mumbai ensued, marking the end of a four hour, gruelling simulator session

After alighting from the simulator,Royde-briefed the crew in what was a highly structured flow of thoughts. During the session, the crew’s performance was recorded in his notebook, and he tackled every comment, in a methodical manner. A good instructor never gets down harshly on his student; rather, effective communication is all about getting your point across in the most pleasant manner. This makes pilots approach the instructor with ease, discuss problems, and arrive at solutions in a welcoming environment. The outcome is clear: safety in the airline rises exponentially.

From Roy, who also flies Dr. Vijay Mallya’s private jet, an ACJ (The business jet version of an Airbus A319), “Dr Mallya, our chairman has always given us a free hand in training budget  as he firmly believes that the returns of good training are in multiples.”

And one of the returns was Kingfisher Airlines being the first inIndiato get a CAT IIIB Approval (An approval which permits the aircraft and appropriately qualified crew to land in extremely poor visibility of not less than 150m with minima of 0ft).

Practice for such poor visibility landings is where the other simulator session comes in: the IR (Instrument Rating) + PPC (Pilot Proficiency Check). “This one is based on a lot of exercises and generally you fly around the airport practicing different failures. We also check the raw data and instrument flying procedures of the crew during this check”, saysRoy. This is the session that holds higher importance, where practicing serious failures makes all the difference in the pilot’s proficiency.

In today’s world, where every airline has sophisticated airliners in its fleet, hi fidelity simulator training is the only way to master these marvellous machines. Issues always spring up with flight deck automation; but it is only a proficient professional pilot who can circumvent any and every situation detrimental to the safety of passengers, and live to be remembered as a true aviator.

As a popular saying goes, “A superior pilot is one who uses his superior judgmental skills to avoid situations which ask for his superior flying skills”.

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2 thoughts on “A320 FFS LOFT Session”

  1. A question: what, if any, stall recovery training programmes are line pilots (here or elsewhere) put though? yp

    The reason I ask is, it’s obviously difficult to simulate a stalled aircraft, and recovering jets isn’t the same as recovering props. I know it’s particularly hard to stall an Airbus, but it’s been known to happen (AF447!). The Air France pilots, by all accounts, were diligent and dutiful, however, in the stall event, their judgement failed them.

    How do airlines normally ensure that their pilots’ post-stall skills do not deteriorate?

  2. wonderful article Vasuki, good to see aviation enthusiasts like you evolving in India.

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