The pilot's own last words could point investigators to the cause of a Tennessee crash that killed four Tampa Bay area people last week and seriously injured a fifth.
The highly regarded pilot of the twin-engine Cessna declared an emergency just before the plane smashed into a ridge line. He radioed that he was experiencing engine icing, according to witnesses who overheard the transmission.
The National Transportation Safety Board's preliminary report on the Dec. 11 crash at the Greeneville-Greene County Municipal Airport says two witnesses heard a garbled transmission from the pilot, David Jochman, in which Jochman said, "Emergency. Engine ice."
The witnesses, who were not named but worked at the Greeneville airport, walked outside and immediately saw smoke about 1.5 miles northeast of the airport.
The NTSB investigation is likely to focus on Jochman's assessment of his emergency because he was such an experienced pilot. Jochman, 49, who was killed in the crash, recently was named the Federal Aviation Administration's southeast regional flight instructor of the year.
Also killed were John Saunders Jr., 40, founder of Saunders Advisory Group in South Tampa; and Saunders' employees, Hani Boutros, 26, of Brandon and Laura Jones, 44, of Tampa. The sole survivor of the crash was John Saunders Sr., who was hospitalized.
The Cessna 414 is a twin-engine, turbo-charged, fuel-injected piston airplane. There are at least two scenarios in which its engines could have developed ice that can rob an aircraft of the power to fly. The NTSB will look at both possibilities.
One involves ice developing on the propellors, which makes them unbalanced and causes the aircraft to vibrate. The more power fed to the engines, the worse the vibration. But slowing the engines can be dangerous because a minimum power level must be maintained to sustain flight.
According to the NTSB, one witness said the aircraft was approaching the airport for landing about 400 feet above the ground, half the altitude it should have had in the landing pattern.
The other possibility the NTSB will examine is whether the air supply to the engines was choked off by ice on the air filters as the plane flew through cold rain between Columbus, Ohio, and Greeneville.
It is not known if the plane was equipped with de-icing equipment.
There were no early indications the plane was in trouble, the NTSB said.
Just before 10:22 a.m., the aircraft requested permission to begin its descent for landing.
The two witnesses said they saw the plane as it neared its assigned runway. They said the landing gear was down, but the plane was too low and out of the normal traffic pattern.
The two then lost sight of the plane and moments later heard the declaration of an emergency.
The plane crashed at 10:50 and was destroyed by fire.
