A cockpit-based system that could overlay an aircraft's real-time position on an electronic airport map would slash the risk of runway incursions

Robert Sumwalt, vice-chairman of the US National Transportation Safety Board and former US Airways and Fortune 500 corporate pilot, points out a glaring gap in a chart on the white board in his office in downtown Washington DC. In the left column are persistent safety threats - controlled flight into terrain, airborne collisions, windshear and ground collisions in the middle, the US Federal Aviation Administration's ground-based solutions to those problems and in the right column, cockpit-based solutions. For each problem area, there are ground-based and cockpit-based solutions to fill the boxes, except for the row labelled "runway incursions".

While the FAA is deploying radar and multilateration-based ground systems to sense and alert potential conflicts between aircraft and other vehicles near runways, there is currently no parallel technology identified for the cockpit that would independently alert pilots to an impending conflict or give them advice on what to do to avoid a crash.

To Sumwalt, that is a problem. "Since 2000, the NTSB has said there needs to be some way to get the warning directly to the cockpit," he says. The topic has been on the NTSB's "Most Wanted" transportation improvements list since then, and the subject of many requests to the FAA in various forms since 1990.

But the lack of an in-cockpit solution is not altogether the FAA's fault - from a technology standpoint, there is no way yet to fill the gap. "I can't yet point to a product that we can say, 'Put this on the aircraft'," says Sumwalt. But new product development efforts in industry, spawned partly by new guidance on electronic flight bags (EFBs) and a groundswell of concern about runway incursions, could soon provide solutions to the problem.

Based on prompting from airlines, the Air Line Pilots Association and the industry's Commercial Aviation Safety Team (CAST), the FAA earlier this year decided to help industry create lower-cost, purpose-built Class II EFBs that are free-standing and do not tie into an aircraft's guidance systems. The idea was to develop a system that would overlay an aircraft's real-time position (called "own-ship position") on an electronic airport map, a situational awareness aid that CAST says could reduce runway incursions by 90%. Having own-ship position on an EFB previously involved a much more rigorous certification process, hence a more costly product.

Although Boeing offers an approved Class III fully integrated EFB with own-ship position and moving maps for 200 airports around the world, the FAA wanted to develop a simpler system that could be obtained for 10% of the price - about $20,000 per unit.

A key part of the solution was to simplify the certification process, says John Hickey, director of the FAA's aircraft certification service. In the resulting Advisory Circular (AC), released in April, Hickey says the FAA "petitioned out" the functionality of own-ship position on the ground, so the EFB hardware itself no longer needed the full technical standard order (TSO) authorisation. Simplifications include removing the need for dual redundancy in the hardware, for example.

Hickey says the FAA is "having conversations" with industry on enhancements to the simplified EFB. These include methods of showing other traffic, perhaps using automatic dependent surveillance-broadcast (ADS-B) when it becomes available, tools that will help cut out the other 10% of runway incursions.

The ball is now in industry's court, says Hickey. "We've done our part - it's up to the business drivers now."

Lower-cost EFB

First out could be a Class II EFB proposed by Thales and L-3 Communications subsidiary, ACSS. The Phoenix, Arizona-based company has announced it will work with Jeppensen, a provider of digital airport moving-map functions, to offer lower-cost Class II EFB systems to the industry. Although the company initially said a system would be ready this summer, the work appears to have been delayed by EFB work the company is providing to cargo carrier UPS.

That system, called SafeRoute, uses ADS-B equipment, Boeing-supplied free-standing electronic flight bags and specialised software enabling UPS pilots to perform self-spacing when arriving at the company's hub airport in Louisville, Kentucky. More in line with the FAA's runway incursion efforts, however, the system will give pilots their "own-ship" position at the airport and show the location of other aircraft if equipped with Mode S transponders, which have ADS-B capability.

UPS plans to put the system into action by the end of August during low-density operations on one approach at Louisville, and have its entire fleet equipped with SafeRoute within two years. After accumulating about a year's flight experience, the company says it will implement some type of audible warning system to alert pilots of potential runway incursions. The wait is necessary, officials say, to learn enough about the system to be able to cut down on nuisance alerts, or false alarms.

A product launch for a low-cost, ground-only version does not appear imminent given the abundance of UPS work. ACSS says it is "in discussion" with other carriers.

Honeywell and Sensis could come up with a more generic competing solution. The two companies are collaborating on a "real-time runway incursion cockpit advisory capability" that will send automated advisories of potential collisions directly to the cockpit and simultaneously to air traffic controllers in the tower using Honeywell's onboard collision avoidance and airport information joined with Sensis' ground infrastructure.

Sensis builds the ASDE-X system now installed at eight US airports and slated by the FAA to be rolled out to 27 others. The system pinpoints the location of aircraft near or on the airport for tower controllers through a combination of radar, onboard transponder returns and a multilateration system set up around the facility.

That data, combined with Honeywell products that determine an aircraft's position in relation to runways, make it possible to compute potential conflicts. The companies are not saying whether the system will include a moving-map display or when a product might be available, but plan to demonstrate the package some time this year.

The system goes a step beyond Honeywell's runway incursion preventative, the Runway Awareness and Advisory System (RAAS), now installed on 200 air transport and regional aircraft and 1,470 business and general aviation aircraft, says the company. RAAS works with Honeywell's enhanced ground proximity warning systems to compare the aircraft's actual satellite-derived position against a regularly updated database containing 1,700 runways. It provides verbal situational awareness reports to pilots on or above the airport.

Airlines are interested in the EFB, but are concerned that requirements for what the system should be able to do are too changeable. "It's like trying to catch a moving target," says Basil J Barimo, vice-president of operations and safety for the Air Transport Association.

NOTAM restructure

One example is a project that is under way to restructure the FAA's Notices to Airmen (Notam) system so it will provide pilots with real-time electronic updates to airport facilities and diagrams, including changes to runway configurations. Without such information, situational awareness tools could provide misleading information. "The Notam system is a weak link in the process," says Barimo. "If you're taxiing on a closed taxiway and don't know it, that's a problem."

But once the technical issues are addressed, Barimo agrees that a low-cost system featuring own-ship position could be a good interim solution for the next 10 years, after which ADS-B is likely to be available for a more comprehensive cockpit view of traffic movement on the ground. Ideally, he says, the future system will be "heads-up". A cockpit-based anti-incursion system will probably be mandated eventually, he adds, but most aicraft will be equipped before a rule is issued, based on incentives for safety and operational efficiency.

Sumwalt is not convinced a mandate will be needed. "The ultimate goal," he says, "is to get the technology in place regardless of how it gets there."


Source: Flight International

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