A group of government and industry organizations has completed certification of the first Bell 429 to conduct steep approaches using wide area augmentation system (WAAS) capability. Involved in the collaborative effort are Bell Helicopter, Air Methods, FAA (including its Global Navigation Satellite System Program Office and Flight Standards Organization), Hickock & Associates, and Des Moines, Iowa-based Mercy Medical Center. Mercy One, a Bell 429 that entered service with the hospital group in April, is approved for 9-degree localizer precision with vertical guidance (LPV) approaches at a minimum velocity for instrument procedures (Vmini) of 45 knots. According to Bell, this will allow Mercy One to employ LPV procedures for steep approaches to accident sites in urban areas, or in adverse weather conditions, improving safety in low-altitude flight.
“This was really a gift to us” from Bell, explained Dan Keough, Mercy’s director of emergency transport, referring to Mercy One being the launch helicopter for the service.
The organizations have developed four fixed WAAS approaches—at Mercy’s main heliport in Des Moines, which will feature a two-way departure, and three other heliports in Centreville, Albia and Osceola. Those four sites are expected to come online in November. A fifth point-in-space rendezvous location will be established early in 2011 above Interstate 80.
By picking Centreville, Albia and Osceola, Keough says, “probably 60 percent of my inter-facility volume is going to come from that triangle we’ve created. And it’s going to allow [Mercy One] to get to those places—they’re telling me that with the two-way departure at Mercy main, I’m going to get out of here at 500 feet [ceiling] and three-quarters of a mile [visibility].”
Keough notes that Mercy averages about 200 “misses” per year due to weather-related concerns, adding that Steve Hickock of Hickock & Associates estimates that the WAAS capability will allow the Bell 429 to recover 50-60 of those misses.
“This WAAS approach and the effect that it’s going to have on our service, from a safety standpoint, from a comfort-ability standpoint—it just makes us that much more effective,” he continued.