The crash of a private jet in which the two top executives of the In-N-Out Burger chain were killed Wednesday afternoon may have been caused by heavy turbulence from a Boeing 757 landing just ahead of it at John Wayne Airport, federal investigators said Thursday.

The fiery crash into a field next to the Santa Ana Auto Mall also killed three others aboard the plane, but no one was hurt on the ground. The crash occurred at the height of the evening rush hour.

In-N-Out President Richard A. Snyder of Newport Beach and Executive Vice President Philip R. West of Irvine apparently had broken a longstanding rule about not flying together and were both aboard the chartered jet.

The National Transportation Safety Board is studying the possibility that the crash may have occurred because the private plane mistakenly crossed the wake of the 757 and may have been affected by the resulting turbulence, officials said.


Don Llorente, a supervisory air safety investigator, said the smaller plane was flying about two miles behind United Flight 103. At one point, the private plane apparently was flying about 200 feet below the larger jet’s glide path, which is not customary, Llorente said.

“If you’re flying behind a heavier jet aircraft, the common technique is to fly at or above the level of the heavier aircraft,” he said.

The crash took the lives of Snyder, 41, president of the Baldwin Park-based restaurant chain and a well-known Republican activist; West, 37, a friend of Snyder’s from childhood; Jack Sims, whose age was not available, a consultant who was also a friend of Snyder’s; pilot Stephen R. Barkin, 46, of Canyon Country, and co-pilot John O. McDaniel, 49, of Long Beach.

Federal investigators have said the jet did not run out of fuel, but they have not eliminated other potential reasons for the crash, including the failure of sophisticated flight-control systems, a loss of power to those systems and pilot error.


Don Miller, a pilot and the representative in Orange County for the Aircraft Owners and Pilots Assn., said he had never experienced problems in flying a small plane even 1 1/2 miles behind a 757, but said it is standard procedure to stay above the level of the heavier plane “because the wake sinks.”

Miller and other commercial pilots said wake turbulence is created by wind swirling off the wing tips, creating twin miniature, horizontal tornadoes as the aircraft flies through the air. Their force is directly proportional to the weight of the aircraft; a heavy plane such as the 757 generates a stronger wake than would a smaller craft such as the corporate jet.

At In-N-Out’s corporate headquarters in Baldwin Park, officials were tight-lipped Thursday about the long-term effect of the tragedy on the privately held company, which is one of the oldest and largest family-owned restaurant chains in the United States. The chain has 93 restaurants, all but four in Southern California, and 35,000 employees.

“The plane was on a business trip and en route to John Wayne (Airport),” company vice president Carl Van Fleet said. “An investigation is under way. The company continues to be operated by staff, and no business disruptions are anticipated.”


The executives’ one-day trip, which began in Long Beach Wednesday morning and was scheduled to end at John Wayne Airport that evening, included a stop in Fresno for the opening of a new restaurant and scouting of other potential locations, according to family friends and company sources. The plane made stops in Orange County, Fresno, Bakersfield and La Verne before heading back to Orange County.

Snyder’s mother, Esther, who founded In-N-Out with her late husband, Harry, in 1948, also had been aboard the twin-engine jet--a Westwind 24A--but disembarked at Brackett Field in La Verne about 20 miles east of Los Angeles, according to a family friend, former Irvine Mayor Sally Anne Sheridan.

NTSB investigators were examining the plane’s wreckage Thursday. It scattered about 30 yards from the point of impact off Edinger Avenue near the 55 Freeway. The crash site was about three miles from the airport. The investigators combed the rubble as dozens of onlookers watched, some through binoculars.

The plane, owned by Robert Gumbiner of Long Beach, was based at Air Flight at Long Beach Municipal Airport. The aircraft had no record of any incidents or service difficulties, according to an FAA spokeswoman.


In-N-Out had a corporate policy forbidding its two top executives from flying together, according to former mayor Sheridan, who was friendly with West and Snyder.

West apparently adhered to the policy and took a commercial flight for at least one leg of the Wednesday trip but then opted to take the chartered jet home, Sheridan said, recounting a conversation she had Thursday with West’s wife, Lori.

Lori West suspected he decided “to get back home to her and her son earlier,” Sheridan said.

Esther Snyder, who serves as In-N-Out’s secretary-treasurer and also works in its accounting department, deplaned in La Verne because she was not feeling well, Sheridan said. Another In-N-Out executive, Bob Williams, also left the plane in La Verne, sources said.


Following the stop in La Verne, the twin-engine plane took off again, heading for the day’s final landing at John Wayne Airport. Moments before the crash, the pilot was cleared for landing by the airport tower, a Federal Aviation Administration spokesman said.

But just after 5:30 p.m., the aircraft suddenly spiraled straight down, plunging nose first into the ground in a field just past the Santa Ana Auto Mall, which was crowded with customers. No one on the ground was hurt.

NTSB and FAA officials said that both aircraft were landing under visual flight rules, which means that the pilots are responsible for maintaining proper distance from each other.

“In this environment, air-traffic operations were normal,” the NTSB’s Llorente said, adding that general separation for John Wayne approaches ranges from 1 1/2 to 2 miles.


An FAA official said the Westwind was told it was following a Boeing commercial jet, which implies a warning about possible turbulence. The last recorded altitude for the small plane was 1,100 feet above sea level. Its air speed was 150 knots.

“We do not know who was flying the aircraft at this time--whether it was McDaniel or the pilot,” he said, but both had flight experience at the airport.

Friends, family members and business competitors mourned the victims Thursday, in particular extolling Snyder, the best-known of the five, as a skilled, careful businessman, a considerate boss, and a deeply religious, charitable man. Snyder is survived by his wife, Christina, his mother, and a brother, Guy.

Snyder was active in conservative political causes. He co-chaired the campaign for the school-voucher initiative, Proposition 174, defeated in last month’s election.


“He had a great love for this country,” Bruce Herschensohn, a Republican U.S. Senate candidate in 1992, said of Snyder, who had been a prominent contributor to Republican conservatives.

Snyder had hosted events for former President Reagan and former Vice President Dan Quayle. Last week, he entertained a group of conservative Sacramento lawmakers in his sky box at a Los Angeles Rams football game.

Contributing to this story were Times staff writers Greg Johnson, Alicia Di Rado, Mike Flagg, Jodi Wilgoren, Mark Platte, Dave Reyes, Willson Cummer and Debora Vrana.

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