Ultra long haul flights

By: steve rowell - 24th June 2005 at 05:57

IN 1950 Charles Lindbergh wrote that his epic 33 1/2-hour solo crossing of the Atlantic in 1927 was an extraordinary battle against the desire to sleep.

"My mind clicks on and off. I try letting one eyelid close at a time while I prop the other open with my will. My whole body argues dully that nothing, nothing in life is quite so desirable as sleep. My mind is losing resolution and control," he wrote.

That battle, while of little interest to passengers, is still fundamental to the success of the world's longest flights - 19 hours from New York (Newark) to Singapore (15,349km) and 17 hours from Los Angeles to Singapore - pioneered by Singapore Airlines in February 2004.

Behind the smiles and charm of the "Singapore Girls" delivering endless attention in the cabin and the seemingly limitless in-flight entertainment options are years of preparation for what is a record-breaking operation -- one that is turning heads as airline CEOs search for a competitive edge.

Qantas is studying joining the ultra-long-haul club using the new 777-200LR or Airbus A340-500s for the 17,016km London Heathrow-Sydney route.

Next month the prototype 777-200LR will visit Sydney as part of a world tour.

Singapore Airlines ordered five A340-500s for the two routes in 1998 and the Civil Aviation Authority of Singapore set up a task force late that year to study ultra-long-range (ULR) flights of more than 18 hours.

The ULR task force included Singapore Airlines and the Singapore Airlines Pilots Association and it consulted extensively with European and US regulators as well as various industry groups and manufacturers.

A key participant was the Washington-based Flight Safety Foundation, which over two years from late 2000 conducted workshops in crew alertness on ULR operations.

As with Lindbergh, the key problem is fatigue on the flight deck, and solutions such as napping and microsleeps that were not an option for Lindbergh but considered quite acceptable on 747-200s and short-range 747-400 operations, would not suffice.

NASA initiated a fatigue/jetlag program in the 1980s in response to a congressional inquiry into fatigue as a safety issue in flight operations. In 1990, the program evolved into a NASA fatigue counter-measures program to emphasise strategies that would address the matter.

But that program, while extremely important, did not address the duty time length required for ULR operations.

With limited data to evaluate, the CAAS ULR task force worked with the European Joint Aviation Authority on computer modelling to study ULR operations.

The results indicated that the operation could be performed by four pilots without experiencing greater problems with fatigue than on current operations.

On long-range operations airlines typically have cycled pilots through one rest period in the first or last half of the flight but this has been found to be deficient.

A study of Boeing pilots on 777-200ER delivery flights by Leigh Signal, Philippa Gander and Margo van den Berg of the Sleep/Wake Research Centre at Massey University in Wellington, New Zealand, revealed problems with this practice.

The study of 21 Boeing pilots found that in the 72 hours before a delivery flight, pilots on average obtained less sleep and accumulated a sleep debt - less sleep than considered necessary to be fully rested - of 4.3 hours.

There was also considerable variance among pilots. Some had zero sleep debt and others had a sleep debt of 10 hours.

In the flight phase of the study, it was discovered that pilots who were rostered to take the first sleep period obtained only 2.7 hours compared to 3.9 hours for the pilots in the second sleep period.

The study found that the one constant was the pilot's age, with older crew members taking longer for sleep onset and then experiencing sleep that was more disrupted. The ULR task force tried the option of two rest periods with Singapore Airlines's 747-400 and 777-200ER long-haul pilots on a volunteer basis over three months. It was found alertness levels increased with a two-rest period, particularly for the crew that rested first.

Emirates has also been at the forefront of sleep studies as it expands its global reach. It also found that having two rest periods reduced pilot anxiety that they must sleep.

The airline is yet to launch its ultra-long-range operations from Dubai to the US west coast but plans incremental increases in sector lengths to get pilots accustomed to flying longer sectors.

Drawing on research and computer modelling, the airline has rostered crews off for three to four days before or after the flight and there is a two or three-day layover in New York or Los Angeles.

Singapore Airlines also brought in experts to advise crews on diet, sleep and exercise to prepare for the flights and how to combat boredom while on duty.

The CAAS required the flights to leave within certain time windows, and approvals were given on a city pair basis.

As soon as the Singapore Airlines ULR flights started last year, CAAS commissioned a group of research laboratories that form the European Committee of Aircrew, Scheduling and Safety, along with the Sleep/Wake Research Centre, to study the flight crews' sleep, alertness and performance.

The Sleep/Wake Research Centre report, released in April, found that pilot alertness on ULR flights was no lower than for other long-range flights.

Researchers from the centre travelled with a flight crew to monitor their sleep, subjective alertness and performance during flight.

Part of the research involved wiring up pilots to sensors that record brain activity, eye movement and muscle tone.

The University of South Australia's Centre for Sleep Research is also conducting comprehensive research into long-haul flying.

According to Drew Dawson, a professor at the centre, the study has collected about 9000 days of data from more than 200 Qantas pilots.

The university's scientists have been working with Qantas and the Australian Civil Aviation Safety Authority and pilot unions to monitor long-haul pilots with duty ranges between 12 and 14-hour flights.

Pilots have been wearing accelerometers and Professor Dawson says that "there are big differences between the amount of quality sleep taken in-flight and that obtained at home. At home, pilots were asleep for 90 per cent of the time allotted for sleep but only for between 65 per cent and 70 per cent during the in-flight rest period".

The research has also involved 60 simulator flights.

In stark contrast to keeping pilots alert, Singapore Airlines strives to create a sleep-inducing atmosphere in the passenger cabin through the use of mood lighting.

Passenger response has been excellent with the flights achieving a 75 per cent load factor. The load factor is also higher in business class and quite often the front end is full with the airline making a healthy profit, say insiders.

On the A340-500s, Singapore Airlines eliminated first class seats, which are more than twice the weight of business class seats.

The A340-500 has 64 Raffles Class (business class) seats and 117 new Executive Economy (EY) seats. Raffles Class has lie-flat beds and EY is set in a 2-3-2 configuration with a 94cm pitch.

Initially, cost for the EY seat was the same as for economy class but it now attracts a 10 per cent premium.

EY seats have a 20.3cm recline and every other seat has in-seat power. The aircraft has 14 cabin crew with a crew passenger ratio of 1:9 in Raffles Class and 1:23 in EY. This compares with 1:13 and 1:32 on the 747-400.

The success of the Singapore Airlines ULR operation is expected to lead to a host of new city pairs with a variety of airlines.

At the same time, Boeing is promising even greater performance from its 777-200LR. New endurance/payload records are to be attempted in October by Boeing.

The company also announced at the Paris air show last week that the 2 per cent fuel burn improvement achieved on the 777-300ER had shown up on the 777-200LR, giving the aircraft the grunt required to perform London-Sydney with an economic payload. But Qantas chief executive Geoff Dixon isn't quite convinced. "Boeing is going to have to prove to us the capabilities of the 777-200LR," he told The Australian. Up to the challenge, Boeing is planning some spectacular, record-breaking test flights later this year.

From a passenger perspective, the ULR flights are effortless. The Australian travelled on Singapore Airlines flight 019 from Los Angeles to Singapore in April. Take-off at 9.30pm was sprightly but quiet and the aircraft hugged the US west coast before tracking over Anchorage, Alaska.

Mood lighting throughout the cabin gave the aircraft an elegant club atmosphere with most passengers taking in a few movies and a meal before settling in for some sleep. From Anchorage, the A340-500 slipped well into Russian airspace and tracked over Beijing, Hong Kong and abeam of Vietnam before crossing the coast near Ho Chi Min City and tracking direct to Singapore. Flight time was 17 hours and 15 minutes.

As the lights of Singapore appeared, just for a whimsical moment the writer felt like standing up and clapping the pilots, who had fought back sleep and somehow found Singapore in the dark. Other passengers did not seem moved to applaud this feat but Lindbergh would have been impressed.