Evergreen International Airlines Inc., the McMinnville-based cargo carrier, has told its employees it will cease operation Nov. 29, the Yamhill Valley News-Register reported Thursday.

The freight airline is a major Yamhill County employer with nonprofit ventures that include an aircraft museum and a water park. Local economic development officials said the parent company employed 463 last year before rising debt forced it to sell off its helicopter division, with 100 workers.

Mike Hines, Evergreen International Aviation Inc. chairman, declined to comment to The Oregonian earlier Thursday on the rumored closure.

“Evergreen Airlines and the other operating companies are currently operating as best they can,” Hines said. “We’re looking at all of our different avenues right now.” He declined to go into details.

The aviation company, which supports the U.S. military and commercial operations, ran into trouble last year as debt soared. Bond rating agencies issued warnings about its creditworthiness. The company paid its employees late multiple times. And McMinnville Water & Light briefly shut off Evergreen’s electricity, apparently for nonpayment.

The News-Register reported the company used a voicemail message to inform employees of the planned closure. The air cargo arm, which once dispatched a fleet of 747s worldwide, is down to a skeleton force, former employees told the paper.

Closure would be a blow to the county and notably to Delford M. Smith, the octogenarian Evergreen group founder, who kept the business alive for decades and launched the adjoining Aviation & Space Museum, Wings & Waves Water Park and IMAX theater. Smith did not return phone calls on Thursday.

In March, Evergreen sold its helicopter unit to Erickson Air-Crane so it could pay down about $276 million in debt.

Evergreen faces legal challenges as well, including an ongoing investigation by the Oregon Department of Justice into money transfers between its commercial and nonprofit ventures. A United Arab Emirates company, UKAS FZC, is suing Evergreen International Airlines, claiming the McMinnville company owes it more than $5 million for air cargo missions UKAS conducted in Afghanistan.

-- Richard Read