He was headed to Double Eagle II Airport (elevation 5,834 feet msl), named after the hot air balloon that three Albuquerque residents used to successfully cross the Atlantic Ocean back in 1978.
This flight would be a new kind of adventure for Dudley. Both the high altitudes and sparsely inhabited spaces that he would be flying over persuaded him to pick his route very carefully. He'd heard the old joke about flying on an IFR (I follow roads) flight plan. Here, following roads seemed more like good sense than a joke. After all, if his engine quit over this high country, he'd rather use a road as a 100,000-foot runway than touch down in any gully hidden by sagebrush and mesquite and many miles from the nearest assistance.
The first part of his flight would take him over relatively flat country, so it was less critical that he stick with his plan of following roads. Nevertheless, Dudley would start by tracing Interstate 70 due west from Hale County before using a series of airways to get to the Tucumcari Vortac.
It was here that the countryside would begin the transition from high plains to steeply rising caprock. Here is where Dudley would fly "IFR" alongside Interstate 40 before turning north for the last six miles into Double Eagle II.
Dudley planned to get some additional mountain flying instruction when he arrived at Double Eagle II, but he had already received some useful advice from a helpful CFI who was familiar with the area. The CFI had warned him to expect significant mechanical turbulence any time that westerly winds exceeding 15 knots hit the steep slopes of the Manzano and Sandia mountains just to the east of Albuquerque.
This time Dudley was using information from www.weatherTAP.com for his flight planning. The Web site, a joint venture between the publishers of Trade-A-Plane and Harris Corp., provides users with the same charts and other data that go to air traffic controllers and flight service station weather briefers. Individuals pay a $63 annual subscription rate.
It was a warm Friday morning in late May when Dudley checked in with WeatherTAP. Dudley went right to the aviation weather section for a look at the big weather picture for his planned trip.
It was early and still cool when Dudley first checked the weather along his route, but he would not be able to depart before 1 p.m. By then temperatures would have risen, possibly stirring up turbulence and even some thunderstorms.
He looked first at the weather depiction chart (Figure 1), which showed that visibility was good-there wasn't even any marginal VFR to worry about anywhere near his planned route.
That was encouraging, but with afternoon temperatures expected to reach close to 90 degrees Fahrenheit, he would certainly have high density altitude to contend with, and convective activity (thunderstorms) seemed likely, too.
The surface analysis chart showed a cold front in southern New Mexico. The radar summary showed no precipitation echoes anywhere in the southwestern United States at this time. The severe weather outlook chart (Figure 2) showed a slight chance of isolated thunderstorms in the foothills of eastern New Mexico spreading slowly into western Texas. The lifted index chart (Figure 3) agreed with this prediction, while the winds aloft chart showed light winds at 10,000 feet-not much to worry about, as far as headwinds were concerned. The 12-hour surface forecast (Figure 4) indicated that high pressure would dominate along Dudley's route for at least the next several hours.
The last plot that he looked at showed high temperatures (Figure 5). While it wasn't exactly going to be a scorcher, those temperatures, combined with the high altitude at his destination, reminded him to account for the decrease in performance caused by high density altitude. He would have to be certain to calculate his takeoff and landing performance and allow plenty of room for error.
Dudley then looked over the high-resolution GOES-10 satellite image, which showed isolated cloud cover along his route. Next, he went to the DTC/DUAT section for a standard weather briefing. The Dallas-Ft. Worth area forecast called for occasional broken ceilings at 5,000 feet with isolated light thunderstorms and rain. The Salt Lake City forecast for New Mexico said that ceilings would range from 8,000 feet to 10,000 feet broken for the eastern plains. The rest of the area would see only scattered clouds at 12,000 feet.
The current conditions showed northeast winds at about 15 kts over most of the route, with 10 statute miles' visibility and temperatures of about 60 degrees. At this point, Dudley began looking at the takeoff and landing performance data in the pilot operating handbook for his aircraft. Luckily, the shortest runway at his destination was about 6,000 feet long, and he would use much more of that pavement than usual on this flight.
By noon, the updated forecasts along his route were calling only for scattered clouds at about 3,000 feet in northwestern Texas going up to 25,000 feet near Albuquerque.
As Dudley flew west, he saw only a very few clouds. The winds were southerly at about 10 kts, almost right down the runway when he landed at Double Eagle II. As expected, the high density altitude did decrease his landing performance significantly, but fortunately, Dudley had done his calculations carefully and had plenty of runway to spare.
He had heard about New Mexico's climate, with its many VFR flying days, and spectacular scenery and he was looking forward to his stay in the Land of Enchantment.
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