Pilot May Have Hit Wake Turbulence

His 100-year-old grandmother told him he was crazy. His former wife didn’t like the idea either, but David Heller was fulfilling a lifelong dream of learning to fly.

Heller had only six weeks of instruction left and was flying solo when his rented Cessna 152 flipped on approach to John Wayne Airport on Tuesday, killing him instantly.

Heller, a Laguna Hills resident and vice president of a credit card company in Anaheim, would have turned 50 on Monday.

His daughter, Michelle Heller, 25, said her father “was finally doing something he wanted to do. He was saying on Father’s Day he wanted to fly over the International Date Line so he could miss his birthday.”

An investigator from the National Transportation Safety Board has said the Cessna’s fall to the ground looked similar to accidents caused by wake turbulence from a larger plane. A Boeing 757 jet had landed a few minutes earlier on a parallel runway, the investigator said, but it is not known if it had any link to the crash.

Wake turbulence is created as planes pass through the air. Trailing from each wingtip, these horizontal vortexes take several minutes to dissipate.

“It’s like intercepting a little tornado at altitude,” said Douglas Baart, who co-authored a 1990 report for the FAA on the dangers of wake turbulence associated with 757s.

If a plane encounters wake turbulence close to the ground, the pilot has less room to maneuver and is in greater danger, he said.

In 1996, the Federal Aviation Administration increased the distance a small plane must stay behind a 757 from four to five nautical miles. The stiffer policy replaced an earlier one set in 1994 after wake turbulence caused two crashes that killed a total of 13 people.

In one instance, a 12-seat corporate jet crashed in Santa Ana, killing all five people on board, including Rich Snyder, president of the In-N-Out Burger chain.

Under the new policy, air traffic controllers are required to warn approaching planes if wake turbulence exists and to instruct pilots to change their speed to avoid landing too close together.

Howard Rifas, a representative of the air traffic controllers union at John Wayne, said that when a pilot is practicing takeoffs and landings, like Heller was, the tower usually leaves it up to him to regulate his distance from other planes, and he must acknowledge that directive.

Before 1994, FAA policy did not require air traffic controllers to issue warnings unless the aircraft was classified as “heavy,” such as a 747 or a DC-10. Boeing 757s are lighter, but some experts have suggested that their sleek design creates particularly violent wake turbulence during landing.

Pilots who do not follow a controller’s instructions are subject to FAA sanctions, agency spokesman Mitch Barker said. No such sanctions exist if a controller fails to issue the warning, he said.

Jeffrey Thorstenson, manager of the control tower at John Wayne, declined comment Wednesday.

Arnold Barnett, an aviation safety expert at the Massachusetts Institute of Technology, said the physics of wake turbulence are not fully understood. He added that there have been cases where a mild vortex combined with a mechanical failure to cause a plane to crash.

An Aliso Viejo pilot who asked that his name not be used described how he was caught in powerful turbulence six years ago when he was learning to fly. He said he was about 200 feet above the start of John Wayne’s runway when he hit turbulence from a 757. He said his small plane spun 90 degrees to the left and jumped 300 yards in less than 10 seconds until he was over the parking lot.

“I learned a lesson,” he said.

Earl McKenzie, who retired in March after flying for United Airlines for 33 years, said that because wake vortexes can even shake up commercial planes, he always tried to keep four to five miles between him and other large aircraft.

Wake turbulence is a particular problem at John Wayne Airport because runways are close together and a mix of private and commercial planes use the airport, said Todd Thornton, a United Airlines pilot who lives in Laguna Beach and often flies there.

McKenzie agreed that the mix of planes at John Wayne leaves greater opportunity for turbulence problems than at airports that serve mainly private planes.

“If I had a small airplane, I don’t think I’d go into places where they have large aircraft on a regular basis,” he said.

But Barker of the FAA said the problems at John Wayne are no greater or less than those at dozens of airports around the country.

“It’s a concern everywhere. Any time you have a mix of aircraft, there’s a possibility of a larger aircraft upsetting smaller aircraft,” Barker said. “That’s why these procedures have been established for separation.”

Because of the mix, students are taught how to handle wake turbulence early in their lessons, said an employee at Sunrise Aviation, where Heller took flying lessons.

“At this airport, they’re taught that from the get-go because of that very situation,” said the employee, who declined to give his name.

A spokesman for American Airlines, whose Boeing 757 landed moments before the rented Cessna crashed on approach, said the company would not comment until the NTSB concluded its investigation.

Heller had once flown to Catalina, and he completed a night flight to Palm Springs last weekend.

Flying “was his thing, and he wanted to do it,” his son Jordan said.

(BEGIN TEXT OF INFOBOX / INFOGRAPHIC)

Invisible Danger

A National Transportation Safety Board official said Tuesday’s plane crash near John Wayne Airport was similar to accidents caused by wake turbulence.

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How Turbulence Is Created

* Air flowing over wingtip creates miniature horizontal tornado (vortex)

* Air continues to rotate, then drops toward ground and dissipates

* Duration of turbulence varies but usually ends by the time the plane has gone three to five miles

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How Planes Avoid Turbulence

* The Federal Aviation Administration generally recommends that small planes fly four to six miles behind and above the altitude of larger aircraft.

* “Pilot-applied visual separation”: Under “visual flight rules,” pilot may accept responsibility for maintaining appropriate distance.

Source: Howard Rifas, National Air Traffic Controllers Assn.