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Pilots use skills to land on short Jackson runway By RACHEL ODELL Jackson Hole News JACKSON - Minutes before landing in Jackson Hole on a clear day last month, most people in the United Boeing 737 had their gazes fixed on the majestic Tetons. Two sets of eyes, however, were too busy to admire the impressive range. In the cockpit, United captain Karen Bland and co-pilot Chris Callahan, looked at everything but the splendid view as they prepared to land on Jackson Hole's 6,300 foot runway. Landing a large jet full of people, baggage and fuel takes special attention at this high-altitude strip considered short by many veteran pilots. On this day, passengers saw the horizon tilt as Bland turned to line up with the runway. The plane dipped as it slowed when she brought the wing flaps down to add drag. There was a slight thump of landing gear lowering. Up front, Bland aimed for the northern-most 1,000 feet of the airstrip, the spot she had to hit to keep the jet from running off the far end. The 737 drifted and lurched, then landed on the asphalt with a light thud. Quickly, Bland pushed the engines into reverse thrust and passengers pitched forward. The engines roared as the brakes exerted their shuddering force, slowing the racing plane to a mellow roll. Bland pressed on the wheel brakes and taxied to a smooth stop at the terminal. Greeting the passengers as they stepped into the fresh Jackson Hole Air, Bland relaxed a minute, knowing the complex calculations made hours earlier allowed her to land safely in Jackson. A pilot for 20 years and a captain for seven, Bland has flown into Jackson for the past five years. Bland's landing was one of many that pilots make every year as they fly roughly 200,000 into Jackson Hole. Each time, careful planning helps them overcome the difficulties of landing a plane on the short runway in the thin mountain air and sometimes in bad weather. Since 1985, 17 planes have slid off the end of the runway; two of them left the strip last December. Since then the FAA has approved plans to add 300-foot paved safety areas at both ends of the runway to reduce the chance of a serious accident on the runway, which is 6,400 feet above sea level. "This is one of the more challenging places we fly into," Bland said. "I always tell my copilot when we are flying into Jackson, be ready for a Navy carrier landing because it is a short runway. It is land and stop! You have to be accurate." For United pilots, that accuracy begins in Chicago where officials working at the operations planning base make a series of calculations that will help the pilot determine how much weight she can carry. Because of the short landing strip at Jackson Hole, pilots cannot always land safely with a full load. Thus, how much the plane weighs is a critical component of the flight plan. With too much weight in certain conditions, a plane's momentum could carry it off the runway. "Anytime you get higher up, your plane performs worse," Bland said. "Add in the fact that you get weather there and that's what makes Jackson a challenge." To determine how much weight the plane can land with safely, pilots must take into account the temperature, the braking friction on the runway, the visibility, the weather forecast and the runway length. The weather is important because it has the potential to affect the ability of the pilot to stop the plane. For example, when the runway is snowy or icy planes may have trouble braking. To counter that handicap, weight can be reduced. "On a 737-300, you would have to reduce your landing weight by over 11,000 pounds if the runway was wet or icy," said Capt. Joe Swenson, United flight manager. Bland's picture-perfect flight would have been significantly different had the runway been slippery. Bland would have had to cut her weight by more than 10,000 pounds. Because United insists on the 4,200 pounds of reserve fuel, Bland would have had to look to baggage and passengers to make her cuts. In such a case, even if all the baggage had been taken off - some 4,000 pounds - more than 30 people also would have had to disembarked before the flight could have left for Jackson. Such are the decisions that can make Jackson-bound flights frustrating for pilots, passengers, and airlines alike. In addition to worrying about runway friction, pilots also must contend with specific regulations regarding visibility. When visibility is bad, that means pilots must carry extra fuel because of the increased chance of being turned back from the Jackson airport. When landing in Jackson Hole, a pilot must be able to see one mile ahead when the plane is 300 feet above the runway. "You must have that visibility reported before even starting the approach," Bland said. "... If there's a snowstorm moving across the field and you cannot see out ahead, you have to divert," or fly off to land at an alternate airfield. Another factor that will cause pilots to take weight off the plane is conditions that cause ice to form on the aircraft. If there are icing conditions and a pilot plans to use deicing equipment on the wings in flight, then she needs to subtract an additional 11,000 pounds. This lowers the total weight and pilots need to compensate by removing passengers, baggage, or fuel. Sometimes a pilot will depart for Jackson but run into bad weather along the way. In that case the pilot may divert instead of landing in Jackson. Until recently United pilots only diverted to Denver. This year they began using airports at Salt Lake City, Cheyenne, and Idaho Falls as alternates. "I want to get there safely," Bland said of her flights to Jackson. "I want to get the people in, too, but I have to do what I have to do."
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