LEYDEN — Small planes can be vulnerable to ice buildup as they fly through moisture-laden clouds in winter.
That’s a possible reason a twin-engine plane crashed in mid-January, an aeronautics expert says, killing three.
A preliminary report from the National Transportation Safety Board noted that ice had formed on portions of the plane.
“Clouds filled with water that haven’t yet turned into snow will cause ice formations on planes if it’s cold enough,” said R. John Hansman, a professor in aeronautics at Massachusetts Institute of Technology.
On Jan. 14, a Beechcraft Baron 55 carrying three people took off from Westfield-Barnes Regional Airport and headed north, traveling at an altitude of around 3,000 feet. Nineteen minutes later, the plane had crashed, killing Fredrika Ballard, 55, owner of aviation school Fly Lugu; William Hampton, 68, a flight instructor; and Chad Davidson, 29, a student pilot.
A preliminary report issued by the NTSB said ice had formed on the airplane’s wings, engine nacelles, horizontal stabilizers, rudder and one propeller blade.
“Ice buildup on planes commonly happens in the winter,” Hansman said.
He explained that when trying to get a plane to its typical cruising altitude, at roughly 7,000 feet, pilots have to climb through cloud layers.
Hansman, who is a pilot with years of flight hours, said ice buildup can affect the plane’s ability to fly properly. “Enough ice on the wings or nose of the plane can lead to engine stalling,” he said.
In aviation terminology, engine stalling can make it difficult for a pilot to maintain their plane’s lift, Hansman said.
The NTSB report said two people who were out walking their dog witnessed the plane’s final moments. They described its engine as sounding “clunky,” adding the engine appeared to shut off before turning back on again.
Two warnings of “moderate icing conditions,” were in place in the region at the time of the crash, the report said. Additionally, a severe weather advisory at the time of the crash warned of “occasional severe turbulence between 3,000 and 16,000 feet due to strong, low-level winds,” the findings said.
Commercial planes are equipped with ice protection, allowing them to fly through the cloud layer with little to no damage to the engine or other parts of the plane. This de-icing protection also allows bigger planes to climb to their typical cruising altitudes between 31,000 feet and 42,000 feet, which is “above (the typical) cloud layer,” Hansman said.
“Smaller, personal planes are not always equipped with the same protection,” he said.
The report does not specify whether the Beechcraft Baron B55 was equipped with this protection.
According to the report, the plane rose to an altitude of about 4,000 feet before it “entered a rapid descent” and then crashed. Investigators noted that witnesses said the plane “corkscrewed straight down and went out of view,” and that the plane “did not appear to make any movements that would indicate it was going to exit the spinning descent.”
While he said he cannot be certain, Hansman explained that “if one wing loses lift and the other one does not, this can cause a corkscrew – which is what could’ve happened with this plane.”
During aviation training, pilots are taught how to handle winter weather, cloud cover, and icy air, he said.
“The protocol is to check the weather and other flying conditions before taking off,” he said. “But it’s not always easy to tell (from the ground) what the conditions will be like once you’re in the air.”
The plane did not receive any air traffic control services during the flight and there were no recorded radio communications either, the report said.
The NTSB findings said that about 20 minutes after the crash, weather reported at the Orange Municipal Airport — 12 miles east of the accident site — included gusting winds, significant cloud cover at 4,600 feet, and visibility of about 10 miles.
The board said it could not comment on the preliminary findings, which were noted as a Class 3 investigation.
According to its website, a Class 3 investigation “seeks to identify safety issues that reveal underlying cause(s) of an accident.”
Investigators will sometimes travel to a location where an accident has occurred and they will speak to witnesses before a final report is released. There are four investigation types.
The board did not say when a final report would be released.
