PHOENIX — A medical-helicopter crash in Tucson that killed three people likely was caused by a mechanic's mistake and the lack of an inspection and testing of his work, according to a recently released federal report.
The report by the National Transportation Safety Board, released last week, said the AS350 B3 Eurocopter had undergone maintenance over several days before the July 28, 2010, crash.
The report, the results of which were first reported by The Arizona Daily Star on Tuesday, says a contract mechanic likely only finger-tightened bolts, instead of using a torque wrench, when he was putting the engine back together. Maintenance personnel did not adequately inspect his work and the pilot who performed a post-maintenance check didn't follow the manufacturer's procedures, the report said.
The LifeNet helicopter left Marana and was en route to its home base in Douglas when it fell 600 feet in eight seconds, crashed into a backyard fence and burst into flames about six minutes after leaving the ground.
The crash was in a densely populated area of Tucson but no one on the ground was injured.
Killed were pilot Alexander Kelley, 61, flight nurse Parker Summons, 41, both of Tucson, and paramedic Brenda French, 28, of Safford.
The report does not specify whether Kelley was the pilot who improperly performed the post-maintenance check, or whether a different pilot performed it.
The check was supposed to take 30 to 45 minutes, but the pilot's check took just seven and a half minutes, the report said.
If a full check was done, the report said the problem that caused the crash likely would have been detected.
In addition, the contract mechanic who put the helicopter's engine back together "was serving as both mechanic and inspector, and he inspected his own work."
Craig Yale, vice president of corporate development for LifeNet Arizona's parent company — Colorado-based Air Methods — said Tuesday that LifeNet made important changes not long after the crash.
Those changes include requiring the company's own staff to inspect the work of any contracted mechanics, and requiring pilots to do full-length maintenance checks.
"This (crash) was several things compounded and some very good people lost their lives," Yale said. "We're going to continue to do everything we can to make sure this doesn't happen again."
He said before the Tucson crash, LifeNet assumed that third-party companies would double-check their own work, but that didn't happen.
"Our lesson learned from this is double check everything, even when the work is done by an outside contractor," he said.
The NTSB report also says that Kelley, who had 14,000 hours of flight experience, had no training flights for nearly a year before the crash.
Although Kelley was not required to undergo additional training during that time, the report said it "may have negatively impacted the pilot's ability to maintain proficiency."
"However, because the engine failed suddenly at low altitude over a congested area, more recent training may not have changed the outcome," the report said.
The report said Kelley likely was trying to get the chopper to an open intersection about 300 feet away from the crash site, but was unable to reach it because he had to maneuver over a row of 40-foot power lines — a maneuver that depleted the engine and caused the helicopter's near-vertical plummet.
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