Getting The Weather Straight

Only two days before the Safety Board went public with its recommendations, the FAA began an eight-month educational program called "Got Weather?" The theme is to help general aviation pilots prepare for potential weather challenges they may encounter. In a promotion for the "Got Weather?" program, FAA Administrator Michael Huerta asked, "Have you fine-tuned your preflight decision-making skills? Are you confident that you can safely complete a flight if you suddenly find yourself in changing weather conditions?"

A weather checklist for pilots to use during the 2014 prime flying season was proposed, containing five salient points. First, the FAA says you should determine whether you're a proficient pilot with the necessary experience and comfort level for flying in marginal weather if you intend to do so. Second, the FAA says you should ask yourself if more training would better prepare you for the flying season. Third, it says you need to ask whether you're really educated about weather, your personal weather minimums and your limits. Next, it suggests you need a flexible safety buffer. Finally, the FAA suggests you talk to others about weather decision making. The FAA's intent was to highlight a specific area of aviation weather each month in the "Got Weather?" program. In May, the highlighted topic was turbulence.

The NTSB says aviation weather products may not contain hazardous weather information that's contained in non-aviation weather products. The Safety Board says this can happen when a particular aviation weather product, such as a Terminal Area Forecast, covers a narrowly defined geographic area, and the adverse weather is just outside of that area. It points to Center Weather Advisories as a type of product that's used to alert controllers to weather conditions, but may not be shared with pilots. The Safety Board expressed concern that the National Weather Service doesn't currently require the issuance of advisories specific to mountain wave activity. "Although the NWS routinely issues products intended to advise pilots, air traffic controllers and other aviation customers of known or expected severe turbulence associated with the jet stream or thunderstorms (indirectly), no standardized NWS product is available to specifically highlight mountain wave turbulence or other phenomena associated with MWA," the NTSB said.

The Safety Board says the weather service should modify aviation weather products to make them consistent with non-aviation products when applicable, so that pilots receive at least the same level of adverse weather information that's available in non-aviation weather products. It also suggests that the weather service establish standard guidance for its forecasters to use in determining whether hazards reported by pilots in PIREPs should be incorporated into aviation weather products they're preparing to issue.

The NTSB cited an accident that occurred on March 3, 2013, involving a Mooney M20E at Angel Fire Airport in New Mexico. The Safety Board said that there was a crosswind at the time of 33 knots gusting to 47 knots. It said that the aviation weather only warned of wind gusts to 25 knots, while two weather products not intended for aviation discussed stronger wind gusts.

The private pilot and three passengers were killed in the accident. The personal Part 91 flight was being operated in VFR conditions and was destined for the Dallas-Fort Worth, Texas, area. Investigators found no evidence that the pilot had received a weather briefing, so even if there had been an aviation forecast warning for high winds, the pilot wouldn't have been aware of it unless he had heard about it from another source.

When the pilot arrived at the fixed base operator, an employee from the FBO questioned the pilot's intent to fly in the windy weather. The pilot indicated that he planned to fly, and that the winds wouldn't be a problem. Due to snow piles on the airfield, the FBO employee couldn't see the takeoff and next saw the airplane airborne with a significant crab angle into the wind, about 40 degrees right of the runway heading. The airplane rose and fell repeatedly as its wings rocked. Then, the employee saw the airplane's right wing rise rapidly. The airplane rolled left and descended inverted with the airplane's nose pointed straight down.

A witness riding in a car along a highway west of the airport saw the airplane take off from the runway. The witness perceived that the airplane was struggling to gain altitude. When the airplane climbed to between 75 and 150 feet above the ground, it appeared to momentarily hover before the left wing dipped quickly and the airplane descended nose first to the ground.

The private pilot's logbook was not available for review by the NTSB. Paperwork filed with the pilot's insurance company reported that as of October 2012, the pilot accrued 459 hours with 384 hours in the same make and model as the accident airplane.

The pilot reported to the FBO manager that he had flown the accident airplane for five years. He added that Angel Fire was the highest airport that he had landed at, although he had flown to some lower elevation airports in Colorado and Wyoming on previous flights.

A cousin of the pilot, who lived in the local area, reported that the night before the accident, he had discussed airplanes and airplane accidents in the Angel Fire area. The pilot reported to him that flying in wind didn't bother him.

Angel Fire Airport and the accident site were located in a basin nearly encompassed by mountainous terrain. Mountains to the west and northwest of the airport have peaks between 10,470 and 13,160 feet. An upper air sounding depicted an unstable vertical environment that would allow mixing of the wind on the lee side of the terrain. Winds as high as 55 knots could occasionally reach the surface. Satellite imagery recorded a large number of standing lenticular clouds around the mountainous terrain around the accident site. These clouds indicated the presence of a mountain wave environment. The National Weather Service issued wind advisories for the accident area that warned of a west-southwest wind between 25 and 35 mph with gusts to 50 mph.

The NTSB determined that the probable cause of this accident was the pilot's loss of control while flying in a turbulent mountain wave environment. Contributing to the accident was the pilot's overconfidence in his ability to safely pilot the airplane in gusting wind conditions and his lack of experience in mountainous areas.

The NTSB's Safety Recommendation also cited a May 24, 2012, accident involving a Gulfstream American AA-5A that crashed about 40 miles northeast of Lakeview, Ore. The pilot, who was the only occupant, was killed. While aviation weather warned of broken ceilings, rain showers and moderate turbulence, the National Weather Service put out non-aviation weather information advising of wintry conditions and significant wind gusts. A review of weather information revealed that the base of the overcast cloud layer in the area was below the tops of some of the terrain. Investigators surmised that the pilot likely flew into snow showers, strong wind and patches of fog, or was trying to maneuver around it when he lost control of the airplane.

The NTSB mentioned an accident that occurred on August 1, 2008, about 40 miles northwest of Yakima, Wash. A Lancair ES disappeared from radar and subsequently crashed, killing both people on board. The investigation determined that mountain wave activity was likely affecting the area around the accident site, but no Center Weather Advisory or SIGMET advisory was valid at the accident time for the accident site. The Safety Board said that the same was true on December 18, 2012, when a Piper PA-31-350 was lost from radio and radar contact about 10 miles southwest of Payson, Ariz. The airplane was on an IFR flight, and the pilot had reported to ATC that he was encountering "heavy up and down drafts." The pilot, who was the only person on board, was killed.

The NTSB says that, historically, about two-thirds of all general aviation accidents that occur in instrument meteorological conditions involve fatalities, which is a fatality rate much higher than for all general aviation accidents. The Safety Board expressed a belief that the fatality rate for IFR accidents could be significantly reduced if valuable information already being produced by the National Weather Service is made readily available to pilots, especially through the use of emerging technologies such as direct broadcast of data to general aviation cockpits.

Peter Katz is editor and publisher of NTSB Reporter, an independent monthly update on aircraft accident investigations and other news concerning the National Transportation Safety Board. To subscribe, write to: NTSB Reporter, Subscription Dept., P.O. Box 831, White Plains, NY 10602-0831.