Air Safety Institute Safety Spotlight
'We can't see!'Most noninstrument-rated pilots have only a few hours of hood time in their logbooks, and these skills quickly atrophy after the private checkride. Caught in low-visibility conditions, the VFR pilot begins to rely on the body's motion- and gravity-sensing organs-a system that is prone to illusion. And a panicked pilot lost in the soup can push an aircraft literally to the breaking point.
On September 4, 2006, the noninstrument-rated pilot of a Cessna 150 became spatially disoriented when he flew into instrument meteorological conditions (IMC) near Penhook, Virginia. The aircraft entered an attitude so extreme that the wings were torn from the airplane in flight. The pilot and his passenger were killed.
The flight left Smith Mountain Lake Airport in Moneta, Virginia, about 11:20 a.m., destined for South Carolina. Marginal VFR conditions prevailed at the time of departure. The pilot did not obtain an official weather briefing from either flight service or DUATS.
Shortly after takeoff, the pilot contacted Roanoke Approach Control and requested VFR flight following. Seven minutes later, he asked the controller for information regarding cloud tops and ceiling. At 11:31 a.m., the pilot asked for a radar vector and admitted, "We're kind of lost in some fog here." The controller asked him to state his present heading, to which the pilot replied, "I can't tell-I think we're upside down." The controller instructed the pilot to turn right, and the aircraft turned to the left.
About 10 seconds later, the pilot announced, "We can't see! We can't see! We can't see!" followed by an unintelligible transmission. No further transmissions were received from the pilot, and radar contact was lost shortly thereafter.
A witness near the accident site reported that he heard "a loud pop." When he looked up, he saw the airplane's fuselage crash into nearby woods, and then observed the wings "floating" down to the ground. Examination of the wreckage revealed that both wings had folded upward near the roots before separating from the fuselage. Weather conditions at reporting stations near the accident site included visibility of two to three miles in rain and mist and overcast ceilings as low as 700 feet. Airmets for IFR conditions and mountain obscuration had been issued about one and a half hours before the accident airplane departed.
The National Transportation Safety Board determined that the accident resulted from the pilot's failure to maintain aircraft control, which led to G-forces in excess of the airplane's design stress limits and, eventually, an in-flight breakup. Contributing factors were the pilot's continued VFR flight into IMC and his spatial disorientation.
Low ceilings and visibilities rank as the greatest weather hazard to the VFR pilot. Thunderstorms, icing, high winds, turbulence-none of these more dramatic, higher-profile threats come close to killing as many pilots as simple, condensed water vapor. Understanding and respecting the weather is crucial. For more information, see the AOPA Air Safety Foundation's Weather Wise series of online courses.
An aviation technical writer for the AOPA Air Safety Foundation, Carl Peterson creates interactive courses and other safety education materials for the aviation community. He has been flying since 1989.
By Carl Peterson