Alaska Airlines has expressed interest in a software upgrade to a runway incursion prevention system that would provide pilots visual warnings in addition to the audible alerts its pilots already receive.
Last year the Boeing 737 operator became the first US carrier to outfit its entire fleet with Honeywell's Runway Awareness Advisory System (RAAS), a software-only augmentation to Honeywell's existing MkV and VII enhanced ground proximity warning systems (EGPWS). RAAS compares the aircraft's actual satellite-derived position with a regularly-updated database containing 1,700 runways and announces information during taxi, takeoff, final approach, landing and rollout.
The visual tool that Honeywell unveiled this June would enable messages to appear on the flight deck map display for eight to 16 seconds.
Alaska would like its pilots to receive routine information via visual warnings instead of aurally, Alaska RNP and aircraft technology engineer Kristin Fuson said on 2 December at the FAA International Runway Safety Summit in Washington.
The Seattle-based carrier is waiting for a price quote and has not signed an agreement with Honeywell for the upgrade, she says.
If Alaska reaches a deal with Honeywell, the carrier could begin using visual alerts as early as the second quarter of next year pending visual messaging receiving FAA type certification for the 737, Fuson says.
But fleet-wide adoption is "more realistic" for the third quarter of 2010, she says, adding that the software upgrade to enable visual messaging would occur during routine aircraft maintenance for the airline's 116 737s.
Visual messaging will cut down on interruptions caused by audible warnings during key communications between the flight crew and air traffic control (ATC), Fuson says, noting that in the meantime flight crews have been instructed to adjust the sound level of ATC communications.
In addition, the airline has already removed audible advisories during critical phases of flight such as when an aircraft is on approach under 10,000 ft (3048m).
The visual tool will also help address the airline's concerns about the sound level of the aural announcements, which Alaska adjusted twice during the implementation process, Fuson says.
But noise level remains an issue because what is too loud is relative and flight crews cannot adjust the volume of RAAS announcements since the volume setting is embedded in the software, she adds. Different advisories also have different volume levels.
Alaska would like to remove routine aural advisories such as on-approach and on-runway if the airline opts for the visual addition to RAAS. However, the airline will continue to use audible warnings for unusual circumstances, Fuson says, providing the example of an aircraft appearing to be taking off from a taxiway instead of a runway.
Honeywell marketing director for surveillance systems Mike Grove says Honeywell went through a RAAS learning curve with Alaska.
He says the alerts were a bit high, but the manufacturer reduced the volumes, and the most recent changes to the visual advisories provide the ability to decrease the volume on aural alerts even more.
Alaska had originally planned to install RAAS in its fleet in 2004 after inking an agreement with Honeywell in July of that year, but concerns from the pilots over the operation of the system halted the work, requiring the airline and Honeywell to fine-tune the tool.
When RAAS was installed, pilot concerns ranged from advisories interrupting ATC communications to pilots being told routine information at an airport they fly to daily. "I know where I am. I fly into Seattle everyday. Why tell me this?" was the response, she says. But pilots operating aircraft to Alaska's less frequently served destinations will say they are "glad" to have RAAS when flying to Boston on a foggy day, for example, she says.
"As we improve the way we use RAAS, we get more and more positive feedback," Fuson adds.