Era Aviation grounded flights during the weekend after a Federal Aviation Administration investigation prompted by a recent altitude loss incident showed cockpit voice recorders didn't meet regulatory standards, FAA officials and a company spokesman said Sunday.
Era spokesman Steve Smith said the airline had learned the cockpit recorders were not up-to-date and needed to be replaced.
The company voluntarily grounded its fleet Saturday afternoon.
"(The cockpit recorders were) an older model and they needed to be updated to a newer model," he said.
Smith said he couldn't explain why the company didn't know its recorders were out-of-date or why the company didn't fix the problem before having to take the drastic step of ceasing flying operations.
"I don't have that answer for you," he said.
Inclement weather in Southcentral Alaska and on the Kenai Peninsula was also a factor in the company's decision to ground its 12 aircraft over the weekend, according to Smith. Passengers were being rerouted onto other carriers or later Era flights, he said.
The FAA investigation that turned up the out-of-date equipment was spurred on Sept. 5 in which a twin-engine turboprop Era plane flying from Anchorage to Homer suddenly dropped from 12,000 to 7,000 feet in altitude with 12 passengers and three crew members onboard, according to an initial report from the National Transportation Safety Board.
No one was injured. The FAA is still investigating the incident.
Hageland Aviation, a carrier under the Era Alaska umbrella, wasn't affected.
As of Sunday the company has the parts to update its equipment, Smith said. The fix could take up to a few days.