Tuesday 28 February 2012
Modern Cockpits Diminish Pilot Skill Levels
Could Civil Aviation Learn From Military Fly-by-Wire Pilot Training?
WASHINGTON (AP) — Pilots' "automation addiction" has eroded their flying skills to the point that they sometimes don't know how to recover from stalls and other mid-flight problems, say pilots and safety officials. The weakened skills have contributed to hundreds of deaths in airline crashes in the last five years.
Some 51 "loss of control" accidents occurred in which planes stalled in flight or got into unusual positions from which pilots were unable to recover, making it the most common type of airline accident, according to the International Air Transport Association.
"We're seeing a new breed of accident with these state-of-the art planes," said Rory Kay, an airline captain and co-chair of a Federal Aviation Administration advisory committee on pilot training. "We're forgetting how to fly."
Opportunities for airline pilots to maintain their flying proficiency by manually flying planes are increasingly limited, the FAA committee recently warned. Airlines and regulators discourage or even prohibit pilots from turning off the autopilot and flying planes themselves, the committee said.
Fatal airline accidents have decreased dramatically in the U.S. over the past decade. However, The Associated Press interviewed pilots, industry officials and aviation safety experts who expressed concern about the implications of decreased opportunities for manual flight, and reviewed more than a dozen loss-of-control accidents around the world.
Safety experts say they're seeing cases in which pilots who are suddenly confronted with a loss of computerized flight controls don't appear to know how to respond immediately, or they make errors — sometimes fatally so.
A draft FAA study found pilots sometimes "abdicate too much responsibility to automated systems." Because these systems are so integrated in today's planes, one malfunctioning piece of equipment or a single bad computer instruction can suddenly cascade into a series of other failures, unnerving pilots who have been trained to rely on the equipment.
The study examined 46 accidents and major incidents, 734 voluntary reports by pilots and others as well as data from more than 9,000 flights in which a safety official rides in the cockpit to observe pilots in action. It found that in more than 60 percent of accidents, and 30 percent of major incidents, pilots had trouble manually flying the plane or made mistakes with automated flight controls.
A typical mistake was not recognizing that either the autopilot or the auto-throttle — which controls power to the engines — had disconnected. Others failed to take the proper steps to recover from a stall in flight or to monitor and maintain airspeed.
The airline industry is suffering from "automation addiction," Kay said.
In the most recent fatal airline crash in the U.S., in 2009 near Buffalo, N.Y., the co-pilot of a regional airliner programmed incorrect information into the plane's computers, causing it to slow to an unsafe speed. That triggered a stall warning. The startled captain, who hadn't noticed the plane had slowed too much, responded by repeatedly pulling back on the control yoke, overriding two safety systems, when the correct procedure was to push forward.
An investigation later found there were no mechanical or structural problems that would have prevented the plane from flying if the captain had responded correctly. Instead, his actions caused an aerodynamic stall. The plane plummeted to earth, killing all 49 people aboard and one on the ground.
Two weeks after the New York accident, a Turkish Airlines Boeing 737 crashed into a field while trying to land in Amsterdam. Nine people were killed and 120 injured. An investigation found that one of the plane's altimeters, which measures altitude, had fed incorrect information to the plane's computers.
That, in turn, caused the auto-throttle to reduce speed to a dangerously slow level so that the plane lost lift and stalled. Dutch investigators described the flight's three pilots' "automation surprise" when they discovered the plane was about to stall. They hadn't been closely monitoring the airspeed.
Last month, French investigators recommended that all pilots get mandatory training in manual flying and handling a high-altitude stall. The recommendations were in response to the 2009 crash of an Air France jet flying from Brazil to Paris. All 228 people aboard were killed.
An investigation found that airspeed sensors fed bad information to the Airbus A330's computers. That caused the autopilot to disengage suddenly and a stall warning to activate.
The co-pilot at the controls struggled to save the plane, but because he kept pointing the plane's nose up, he actually caused the stall instead of preventing it, experts said. Despite the bad airspeed information, which lasted for less than a minute, there was nothing to prevent the plane from continuing to fly if the pilot had followed the correct procedure for such circumstances, which is to continue to fly levelly in the same direction at the same speed while trying to determine the nature of the problem, they said.
In such cases, the pilots and the technology are failing together, said former US Airways Capt. Chesley "Sully" Sullenberger, whose precision flying is credited with saving all 155 people aboard an Airbus A320 after it lost power in a collision with Canada geese shortly after takeoff from New York's LaGuardia Airport two years ago.
"If we only look at the pilots — the human factor — then we are ignoring other important factors," he said. "We have to look at how they work together."
The ability of pilots to respond to the unexpected loss or malfunction of automated aircraft systems "is the big issue that we can no longer hide from in aviation," said Bill Voss, president of the Flight Safety Foundation in Alexandria, Va. "We've been very slow to recognize the consequence of it and deal with it."
The foundation, which is industry supported, promotes aviation safety around the world.
Airlines are also seeing smaller incidents in which pilots waste precious time repeatedly trying to restart the autopilot or fix other automated systems when what they should be doing is "grasping the controls and flying the airplane," said Bob Coffman, another member of the FAA pilot training committee and an airline captain.
Paul Railsback, operations director at the Air Transport Association, which represents airlines, said, "We think the best way to handle this is through the policies and training of the airlines to ensure they stipulate that the pilots devote a fair amount of time to manually flying. We want to encourage pilots to do that and not rely 100 percent on the automation. I think many airlines are moving in that direction."
In May, the FAA proposed requiring airlines to train pilots on how to recover from a stall, as well as expose them to more realistic problem scenarios.
But other new regulations are going in the opposite direction. Today, pilots are required to use their autopilot when flying at altitudes above 24,000 feet, which is where airliners spend much of their time cruising. The required minimum vertical safety buffer between planes has been reduced from 2,000 feet to 1,000 feet. That means more planes flying closer together, necessitating the kind of precision flying more reliably produced by automation than human beings.
The same situation is increasingly common closer to the ground.
The FAA is moving from an air traffic control system based on radar technology to more precise GPS navigation. Instead of time-consuming, fuel-burning stair-step descents, planes will be able to glide in more steeply for landings with their engines idling. Aircraft will be able to land and take off closer together and more frequently, even in poor weather, because pilots will know the precise location of other aircraft and obstacles on the ground. Fewer planes will be diverted.
But the new landing procedures require pilots to cede even more control to automation.
"Those procedures have to be flown with the autopilot on," Voss said. "You can't afford a sneeze on those procedures."
Even when not using the new procedures, airlines direct their pilots to switch on the autopilot about a minute and a half after takeoff when the plane reaches about 1,000 feet, Coffman said. The autopilot generally doesn't come off until about a minute and a half before landing, he said.
Pilots still control the plane's flight path. But they are programming computers rather than flying with their hands.
Opportunities to fly manually are especially limited at commuter airlines, where pilots may fly with the autopilot off for about 80 seconds out of a typical two-hour flight, Coffman said.
But it is the less experienced first officers starting out at smaller carriers who most need manual flying experience. And, airline training programs are focused on training pilots to fly with the automation, rather than without it. Senior pilots, even if their manual flying skills are rusty, can at least draw on experience flying older generations of less automated planes.
Adding to concerns about an overreliance on automation is an expected pilot shortage in the U.S. and many other countries. U.S. airlines used to be able to draw on a pool of former military pilots with extensive manual flying experience. But more pilots now choose to stay in the armed forces, and corporate aviation competes for pilots with airlines, where salaries have dropped.
Changing training programs to include more manual flying won't be enough because pilots spend only a few days a year in training, Voss said. Airlines will have to rethink their operations fundamentally if they're going to give pilots realistic opportunities to keep their flying skills honed, he said.
Monday 27 February 2012
Fatigue and Circadian Cycles
Introduction
Flight operations and shift work/patterns that involve irregular work hours, night flights and early starts or transmeridian flights force pilots and shift workers to deviate from their normal work/sleep schedule and disrupt their biological rhythms. Many of our biological and behavioral functions experience variations throughout the day, including: sleep, body temperature, alertness levels and mental and physical performances. Many of these functions vary systematically in a cycle of about 24 hours and are called "circadian rhythms" (from the Latin words "circa" which means "about" and "dies" which means "a day"). These circadian variations are governed by a biological clock located in the brain. Crew members and ground operations shift workers who work abnormal schedules often experience “shift-lag syndrome,” which is characterized by such symptoms as feelings of fatigue, sleepiness, insomnia, disorientation, digestive trouble, irritability, reduced mental agility and reduced performance efficiency. Similar symptoms labeled “jet-lag syndrome” are often experienced by crew members after transmeridian flights.
The mechanism underlying circadian rhythms is called the “biological clock” or the “circadian clock.” Research has shown that the biological clock is located in the suprachiasmatic nucleus of the hypothalamus (a gland). The biological clock is probably the result of human evolutionary adaptation to the solar day.
Laboratory studies have shown that, in the absence of any time cues (i.e., no sunlight or social time cues), the biological clock for most humans operates on a cycle of about 25 hours.
Under ordinary circumstances, however, the biological clock is reset by about one hour each day such that the biological clock is synchronized with the 24-hour solar day. The cues that serve to reset the biological clock are called “zeitgebers,” a German word that means “time givers.” Evidence supports morning sunlight as the most important zeitgeber. Other cues in the social environment that serve as zeitgebers have not been identified with any amount of certainty. However, cues that may serve as zeitgebers include work/sleep schedule, eating schedule, social activities and, in the absence of other cues, subtle environmental factors such as building vibration and traffic noise.
Although the biological clock can routinely be reset by about one hour each day, it cannot easily and quickly be reset by the large time quantities that are needed following significant changes in work/sleep schedule or a transmeridian flight. The slow adaptation of the circadian clock contributes to problems in conducting night operations and transmeridian flights.
Data
Many laboratory studies have demonstrated circadian variations in biological functions such as body temperature, cell division and hormone secretion. Also, both laboratory studies and field studies have demonstrated variations related to circadian rhythms in behavioral functions such as alertness, reaction time, short-term memory, long-term memory, search tasks, vigilance and sleep. The circadian variation throughout a normal solar day is not the same for all biological and behavioral functions. There are, however, general trends in certain bodily functions/parameters likely related to circadian relations.
The body temperatures of individuals adapted to local time and to a normal work/sleep cycle (i.e., sleep at night) vary systematically with circadian rhythms. Body temperature is lowest during the early morning hours from about 2 am to 6 am and starts to rise from this low point at about the normal waking hour. Thereafter, body temperature tends to rise until late afternoon or early evening, at which point it starts a decline that continues until it reaches its low point in the early morning hours. The circadian variation in body temperature is virtually the same for active and non-active individuals. It has been suggested that body temperature is an indicator of the body’s readiness to perform work.
The results of research support several conclusions about circadian rhythms that are useful in maximizing pilot performance. Circadian variations in work efficiency are not the same for all tasks. Also, under a normal work/sleep schedule and complete adaptation to the local solar day, performance efficiency does not remain the same throughout the day. For many tasks, performance efficiency tends to increase from the normal wake-up time in the morning to a peak in the early or late afternoon. Performance efficiency on some tasks shows a temporary decline following lunch time, even if a meal is not eaten. It is important to point out that work efficiency in these studies was tested periodically (and briefly) throughout the day (about 8 am through 9 pm), so fatigue was not a factor affecting performance. Performance efficiency tends to decline to a low point in the early morning hours ( 2-6 am). The important implication of this research is that circadian rhythms influence performance efficiency even when the circadian variations are in synchrony with the solar day and the normal work/sleep schedule.
The effects of circadian rhythms on safety are difficult to assess because they are virtually always confounded with other contributory factors. However, the following findings suggest that the effects of circadian rhythms are, in part, responsible for:
The number of motor vehicle accidents on roadways peaks between 2 am and 6 am and again around 3 pm. These are the times of maximum sleepiness due to circadian rhythms
Risk of injury is 30 percent higher during night shifts than during day shifts, and the difference increases over successive night shifts until the difference reaches a high of 39 percent increased risk of injury on the fourth night.
Research also has demonstrated that a host of problems occur when circadian rhythms are not in synchrony with the work/sleep schedule imposed by a person’s job. Such asynchrony can result from a change in work schedule, transmeridian flight, or a combination of the two. Such asynchrony is important for two reasons. First, the job may require an individual to perform work at a phase during the circadian cycle when performance efficiency is low. Second, disrupting the normal work/sleep schedule decreases the amount and quality of sleep, which leads to fatigue .
Night Operations
Night operations create a host of problems for flight crews and Ground Operations shift workers. The primary problem is having to work efficiently and safely at a point in time when the work requirements are not in synchrony with circadian rhythms. Under worst-case conditions, crew members and shift workers must perform demanding tasks during the early morning hours (2 am to 6 am) when their biological functions and performance efficiency are at their lowest level. This problem cannot be quickly solved by adaptation of the biological clock. Complete adjustment to night work requires at least 21 night shifts in a row with no days off. Adjustment of the biological clock does not even commence until about 10 days after a shift change. In fact, it has been argued that crewmembers never fully adapt to night operations because:
(a) they do not stay on the night shift long enough to adapt fully; and
(b) they revert to a regular routine during their days off, thereby stopping or reversing the adaptation process.
In addition, the light-dark cycle works against adaptation to night operations. The morning sunlight experienced during the drive home from work prevents adaptation by resetting the biological clock back to the normal solar day.
As stated earlier, prolonged asynchrony between circadian rhythms and work requirements causes crew members to experience shift-lag syndrome, which is characterized by feelings of fatigue, sleepiness, insomnia, disorientation, digestive trouble, irritability, reduced mental agility and reduced performance efficiency
Sleep difficulties are a major problem for crew members and shift workers who participate in night operations. Both the duration and quality of sleep are affected. Daytime sleep following night operations is generally of poor quality due to shorter durations than normal night sleep and because it is more susceptible to interruption, which results in fewer and shorter periods of deep sleep. After a period of night work and daytime sleep, a sleep deficit can accumulate that results in cumulative fatigue. This cumulative fatigue can further exacerbate the difficulty of maintaining efficient and safe performance during night operations.
There is some evidence that the effect of night work is more severe among older workers, and shift workers are more tired when driving to and from work than non-shift workers.
For the reasons discussed above, the adaptation to night work is never complete. More complete adaptation can be achieved for permanent night work than rotating shift work or irregular work hours, but the requirements of air operations seldom enable flight crew members to work the same shift for more than a few days.
Jet lag
Symptoms of jet lag include feelings of fatigue and inertia, difficulties in concentrating and sleeping, gastrointestinal problems and a general malaise. The syndrome is distinct from so-called “travel fatigue,” which is the tiredness experienced after a long and often stressful journey. Travel fatigue occurs for both transmeridian flights (east/west across time zones) and translatitude flights (north/south with little or no time change). With travel fatigue, there may also be residual stiffness due to remaining in a cramped posture for a long time. The effects of jet-lag syndrome on the individual's mental performance may be subliminal and go unnoticed while other symptoms may be more obvious during the period of adjustment to the new time zone.
Under normal conditions, the biological clock is in phase with the environmental synchronizers. The period of least efficiency coincides with the nocturnal period, and the period of optimal efficiency coincides with the diurnal period. At the end of a transmeridian flight and for a period thereafter, the circadian system and environmental synchronizers are out of phase.
Table 1 illustrates the mismatch between “body clock time” and local clock time following a transmeridian flight that covers eight time zones in an eastward direction.
Table 1. Mismatch between local times and “body clock time” immediately after an 8-hour time-zone transition eastwards.
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As stated earlier, the biological clock does not immediately adjust to new time zones. The amount of time required for the biological clock to adjust to a new time zone depends on the individual, the direction of flight, the number of time zones crossed and the individual’s exposure to environmental cues.
The direction of the time zone change has been shown to have a substantial affect on adaptation time. Adaptation after eastbound flights is about 50 percent slower than after westbound flights. For eastbound flights, about 1.5 days of recovery time is required for each time zone change compared to about one day of recovery time for each time zone change in westbound flights. The difference in recovery time is due, in part, to the fact that the free-running cycle of the biological clock is longer than 24 hours. The difference is largely a function of differences in adapting to a new sleep schedule. Indeed, the adjustment after eastbound flight requires a crewmember to go to sleep and get up earlier while adjustment after westbound flight requires a crewmember to go to sleep and get up at later hours.
In addition to this differing rate of adaptation due to direction of travel, psycho-physiological functions adjust at various rates depending on the individual. It is also relatively common for travelers to adapt in the wrong direction, such as delaying 16 hours instead of advancing 8 hours.
Defenses Against Circadian Rhythm Disruptions
A number of strategies can be used to counteract the effects of transmeridian and translongitudinal flight. To counteract disruptions to your circadian rhythms:
Know your normal body clock times for sleeping and eating by using the Body Clock Questionnaire (BCQ)
Determine how you are adjusting to local time during layovers by using the Layover Adjustment Questionnaire (LAQ)
Based on the BCQ and LAQ, attempt to modify your sleeping and eating schedules to adjust for maximum alertness. Try to only eat meals and drink coffee or tea at times when your sleep will not be adversely affected.
Use good nap management before and during flight or during your shift (if allowed). Coordinate rest and meal periods with other crew members or shift staff.
Exercise at appropriate times
Expose yourself to sunlight at appropriate times
Summary of Key Points
Many human biological and behavioral functions vary regularly and systematically over a period of about 24 hours. These variations are called circadian rhythms
Circadian rhythms persist even in the absence of all environmental and social time cues
Circadian rhythms are internally generated by a self-sustaining or autonomous biological clock located in the hypothalamus
In the absence of all time cues, the biological clock has a natural cycle of about 25 hours. With normal time cues, however, the biological clock is reset each day such that it is in synchrony with the solar day.
Changes in work shifts and transmeridian flight result in asynchrony between a crewmember’s circadian rhythms and both work requirements and environmental time cues
This lack of synchrony results in shift-lag syndrome (due to changes in work schedule) and jet-lag syndrome (due to transmeridian flights)
The biological clock and the associated circadian variations adapt slowly following changes in the work schedule and following transmeridian flights
Adaptation after eastbound travel is about 50 percent slower than after westbound flight -- adaptation time following eastbound travel is about 1.5 days for each time zone change whereas adaptation time following westbound travel is about one day for each time zone change
The adaptation rate is not the same for all of the circadian biological and behavioral variations. The resultant disharmony among these functions contributes to jet-lag syndrome.
Russia’s Putin strongly warns against military intervention in Syria, attack on Iran - The Washington Post
In between a busy vote 'management' schedule Vladimir Putin manages to say this:
Russia’s Putin strongly warns against military intervention in Syria, attack on Iran - The Washington Post
Tuesday 21 February 2012
Fuel Conservation
oil at $200 a barrel human ingenuity and alternatives
Are you an operator operating to JAR/EU-OPS or variants thereof ? Then various techniques exist where operators can take full advantage of the fuel allowances and reserves that are available to you.
In accordance with detailed risk analyses large savings are achievable. Want to know more ? Contact me or leave a comment and I will get back to you.
Iran Manipulation of Oil Supplies Poses a Serious Threat to Aviation
iran energy feud could spell $150 per barrel
Fuel surcharging will make the passenger pay for extremist politics Iranian style. Airlines that resist fuel surcharging will feel the pinch and may not survive if the price hike is protracted.
Fuel surcharging will make the passenger pay for extremist politics Iranian style. Airlines that resist fuel surcharging will feel the pinch and may not survive if the price hike is protracted.
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