BRENDAN SOBIE / ANCHORAGE, BETHEL & EEK, ALASKA

In a land of ice and snow, where there's an air accident every 48 hours, the Capstone project is offering Alaskan fliers a safer future

Three years and $20 million into a US Federal Aviation Administration project that has potential worldwide ramifications, free-flight technologies have changed the face of bush flying in remote western Alaska. Accident rates are still high compared to the rest of the world, but have been reduced, giving the entire state hope that the days of a crash every 48h are coming to an end. Air taxi pilots and their passengers, who often rely on air transport as the sole means of getting out of town, are flying more confidently. Controllers and dispatchers can keep in contract with aircraft at all times, providing a higher level of comfort and improving the efficiency of operations.

The automatic dependent surveillance broadcast (ADS-B) system, coupled with the global positioning system (GPS) and improved weather and terrain data, have been a life saver for local pilots. The technologies on trial in this corner of the world as part of the FAA's Capstone project could also provide a glimpse into the future.

"By the end of the decade these technologies will be commonplace throughout Alaska and all over the world," says regional FAA administrator Patrick Poe.

But the pace of the project has been slow, the findings have been preliminary and questions remain about the exportability and affordability of the technologies. John Hallinan, Capstone project manager, agrees that it is "still too soon to tell" how the project is progressing, while free-flight field co-ordinator Gary Childers warns: "At some point, this system has got to be affordable and robust. The government can't pay for installations for ever."

For small native villages on the Yukon Kuskokwim Delta such as Eek, the verdict is already in. Eek is one of over 200 Alaskan communities that have no road connections. Its 283 inhabitants, mostly salmon fishermen, rely on small aircraft to transport them, their cargo and their mail. Eek's 460m (1,500ft) gravel runway can only be accessed in visual flight rules (VFR) conditions, meaning that the village is cut off in poor weather.

Capstone technologies have given air taxi operators added security in reaching Eek and two dozen other communities in the region, especially during marginal weather.

White-out conditions

VFR-only air taxi operators are cleared to leave Bethel for the villages as long as the ceiling is at least 500ft, half the ceiling required for VFR outside the region. Flights typically cruise at well under 1,000ft. Foggy and white-out conditions are regularly encountered. There are few ground-based navigation aids and there is no radar coverage below 5,000ft. The Capstone display solves all these concerns, providing terrain data, traffic information pinpointing the location of other participating aircraft, a communication link with controllers via ADS-B, up-to-date weather information via the flight information service broadcast (FIS-B) and navigational data via GPS. "It's a real life saver," says Article Circle Air pilot James Christensen. "I don't think we could operate here the way we do without it."

ADS-B has also given several Bethel-based air taxi operators a tool for flight monitoring. Before the Capstone project, dispatchers would be incommunicado with aircraft for hours at a time. With ADS-B, search and rescue missions can be launched quickly. The technology also provides locations of possible crashes because it stores the flight tracks of participating aircraft.

According to Flight Alaska chief operating officer Skip Nelson: "We're moving more cargo, more aircraft and more people than ever, because Capstone has given us better use of assets, a more orderly flow."

There are other, less-obvious benefits from Capstone. Hageland Aviation Services director of operations Hugh Youngers says: "There has been a definite improvement in morale among the pilots flying for us. We think it will meet the goal of reducing accidents by 35%."

Youngers says passengers are starting to ask before boarding if the aircraft is Capstone-equipped. The FAA has so far funded the installation of Capstone technologies in about 180 aircraft, including every air taxi in the Yukon-Kuskokwim Delta. Based on accident data from 2000 and 2001, when only a fraction of the region's fleet was equipped, FAA consultant Mitre has determined that Capstone aircraft have 40% fewer accidents than non-participating aircraft. It estimates that 25% of controlled flight into terrain or preventable navigation accidents and 11% of mid-air collisions would have been avoidable if the aircraft had Capstone technologies.

"The Capstone programme can prevent controlled flight into terrain as well as collisions and other accidents better than any other technology I've seen," says Alaska Senator and private pilot Ted Stevens. "Our pilots need more information wherever they are. Capstone will be able to do that."

Stevens and other Capstone proponents expect the accident rate in the Yukon-Kuskokwim Delta and Alaska overall to continue to drop as the programme expands. Capstone officials plan to extend the trials in western Alaska to incorporate additional technologies and simultaneously expand the programme to south-east Alaska.

Capstone officials hope to improve the flow of aircraft around Bethel, which can become dangerously saturated when weather conditions deteriorate. En route air traffic controllers at Anchorage centre only began using ADS-B to separate Capstone participating aircraft in January 2001. The technology has allowed controllers to provide a radar-like service in western Alaska where radar is unavailable, but it has limitations. For example, controllers must keep aircraft (9km) 5nm apart and have to terminate the service when they approach Bethel.

Childers says the FAA is confident it can certificate the system for 3nm separation given its performance so far. He says the FAA also hopes to insert a terminal control area for Bethel approaching and departing aircraft. Bethel's control tower is now limited to providing VFR services and received an ADS-B display only in July.

Better separation

The ADS-B display allows Bethel controllers to vector and separate traffic better. Controllers previously had to place VFR aircraft in set holding patterns when weather deteriorated, resulting in lengthy delays. Youngers expects the forthcoming winter season to be vastly improved, thanks to the tower display, with aircraft "getting on the ground quicker and safer".

The recent increase in instrument flying rules (IFR) traffic at Bethel, however, has exacerbated the delays experienced by the VFR aircraft during marginal weather. Nearly half the air taxi fleet is now IFR qualified. The rise in IFR equipage has been made possible by the introduction of eight non-precision GPS approaches funded by Capstone. The FAA has installed automated weather stations at nine remote airports to support the new approaches and Childers says more installations are planned.

The FAA has extended the trials in western Alaska for another two years because the data gathered so far is insufficient. "We'll leave it in place as long as need be," Childers says.

Meanwhile, the second phase of Capstone will begin in south-east Alaska's autumn. In addition to extending all the Bethel technologies southward, Capstone officials plan to test the wide area augmentations system (WAAS) in the Juneau area, potentially opening airports and airways in mountainous areas during weather conditions that now require their closure.

With WAAS, Hallinan believes the availability of en route service in Alaska could increase from 98.5% to 99.99%.

WAAS is not set to be FAA certified until next year, but Hallinan expects a seamless transition to testing the system in south-east Alaska. "We'll be the first WAAS customers out there," he predicts. How far Capstone and its free-flight technologies ultimately will be extended, however, remains an open question.

Beyond south-east Alaska, there are plans for a phase III in northern Alaska and possible statewide tests. Stevens insists Washington DC, including new FAA administrator Marion Blakey, is aware of the crucial role Capstone technologies play in promoting safety, adding: "I believe we'll get the money we need."

Capstone has become a household name in Alaska, where there is one aircraft for every 100 people. The programme is widely viewed as the solution to Alaska's appalling aviation safety rate, which includes one fatality every nine days. Eleven per cent of commercial pilots with 30-year careers in Alaska lose their lives in aircraft crashes, compared to a 2.5% rate for pilots in the continental USA.

"Alaska is the perfect incubator for the new technologies," Nelson says.

Further trials

Trials of ADS-B in Australia, Russia, Sweden and other countries, however, could lead to development of an improved platform, while others believe that traffic information system broadcast (TIS-B) technology could provide a better solution and leap over the ADS-B system.

Mitre, in its study, warns that further data has to be gathered before any real safety conclusions are made. Capstone officials, however, are confident what they are incubating will be extended to continental USA and perhaps beyond. "Our focus is on meeting Alaska's needs, but we can make sure this is deployable nationwide," says Capstone programme official Mark Olson. Adds Childers: "We really feel the manufacturers and the industry are bracing for this stuff and feel comfortable producing them en masse."

Source: Flight International