Tower Warnings Ordered on 757s’ Turbulence : Aviation: FAA order follows Santa Ana crash that killed five people. Agency says it has had indications since February of disturbance caused by the Boeing jets.

Citing last week’s crash of a private jet that killed five Southern Californians, the head of the Federal Aviation Administration instructed air traffic controllers nationwide Wednesday to begin warning small planes of the dangerous turbulence caused by Boeing 757 jetliners.

In response to inquiries from The Times, the agency said it has had indications since February that the mid-size 757 causes as much wake turbulence as a giant Boeing 747 or a McDonnell Douglas DC-10, but only issued the new rule to FAA tower operators after the crash in Santa Ana.

At least four incidents involving at least 13 fatalities in the last year may be linked to turbulence caused by Boeing 757s, the FAA said.

“Several incidents involving aircraft following or crossing the flight path of the Boeing 757 have created concern for the safety of aircraft in connection with the wake turbulence created by the B-757,” reads a mandatory briefing item flashed via Telex to control towers Wednesday.

“Accordingly,” the message continues, “to ensure that pilots are aware of the potential wake turbulence hazard created by the B-757, controllers shall provide a wake turbulence cautionary advisory to following aircraft.”

Some air traffic controllers at John Wayne Airport said they had been giving such warnings about Boeing 757s even before FAA Administrator David Hinson issued the new policy. A Times reporter listened to air traffic controllers Tuesday evening and heard several such warnings as Boeing 757s were landing.

Local FAA officials insisted Wednesday, however, that they were not legally required to do so.

The National Transportation Safety Board said Wednesday that the pilot of the 12-seat Westwind that crashed last week received no such warning. Nor was he told, NTSB investigators said, that he was trailing a Boeing 757.

FAA spokeswoman Elly Brekke said she did not know why some controllers had been issuing such warnings to pilots flying behind B-757s. But she added that the air traffic controllers handbook does not require them to identify the type of aircraft or issue turbulence warnings unless the aircraft is classified as a “heavy,” such as a 747 or DC-10.

Brekke, quoting from the handbook, said: “Because wake turbulence is unpredictable, the controller is not responsible for anticipating its existence or effect.”

It’s unclear whether that sentence from the regulations absolves the FAA controllers’ handling of the landing approach accident, however, and last Wednesday’s crash has been the subject of controversy in aviation circles over just how much responsibility pilots should bear.

The handbook seems to suggest that controllers must issue wake turbulence advisories whenever, in their opinion, wake turbulence may be a factor for an aircraft trailing heavy jets such as the Boeing 747 or the DC-10.

Since the FAA changed its handbook in February to indicate that Boeing 757s cause heavy turbulence, some pilots think it’s reasonable to expect a controller to have issued a turbulence warning to Westwind pilot Stephen Barkin even though, technically, the B-757 is not classified as a heavy.

“It would have been nice if he had at least been given a warning,” said Peter Murray, a longtime airline captain who flies 757s and has warned about the turbulence they cause.

“The Westwind is told that it’s a Boeing jet but there are all kinds of Boeing jets out there at John Wayne Airport,” he said. “You cannot throw the entire burden of flying on the pilot. Approach controllers and towers should separate aircraft out there because they know the exact spacing. Pilots can only guess.”

Hinson’s directive also comes as a result of three other incidents involving turbulence from the Boeing 757 that caused other planes to roll or crash.

In addition to last week’s crash, Hinson cited a December, 1992, crash of a twin-engine jet in Billings, Mont., in which eight people were killed, and the crash of a single-engine Cessna last month in Salt Lake City, in which three people were injured. Hinson made reference to one other instance in which a Boeing 737 “experienced an uncommanded roll” this year over Denver after encountering the wake of a Boeing 757.

The FAA first alerted controllers of the B-757 turbulence problem in February when the B-757 was singled out in the controllers handbook for its problems.

Murray, the airline captain, said that although Hinson’s directive is laudable, it falls far short of what is necessary to make the skies safe around John Wayne Airport.

“It would be better for the controllers to put the burden on themselves,” he said. “The warnings are nice but a controller can’t just say, ‘Well, we warned them and that’s it,’ because people die.”

Last Wednesday’s crash killed the two top executives of the In-N-Out Burger chain and a marketing consultant. The pilot and co-pilot also died.