PHILADELPHIA (AP) - A disgruntled ex-Boeing worker admitted Thursday that he disabled a nearly finished, $24 million military helicopter during his last shift on the assembly line.

Matthew Montgomery, 33, of Trevose, had applied for several transfers to other Boeing facilities, but was instead being moved to another job within the suburban Philadelphia plant. He used his work-issued wire cutters to sever about 70 electrical wires running together from the cockpit to the main body of an H-47 Chinook on Saturday, May 10.

Montgomery pleaded guilty Thursday to one count of destroying property under contract to the government.

The damage he inflicted was easily spotted two days later by plant officials. The helicopter would not have been able to fly, prosecutors and his defense attorney agree.

"There was no danger of this getting off the ground with the electrical wires being cut," public defender Mara Meehan told the judge.

Boeing officials focused on Montgomery within a week, and he readily admitted his role in a May 19 interview.

The day Boeing officials found the severed wires, they also found a suspicious washer in the transmission of an adjacent Chinook at the Ridley Park plant.

No one has been charged and Montgomery is not implicated, officials said. Army investigators in court Thursday declined to elaborate on their progress in that case.

The Chinook, the Army's workhorse, is designed to transport troops and supplies to combat and other regions. Boeing is producing new Chinooks for the Army, as well as updating older models.

The Boeing plant is highly prized in Delaware County, and local officials were quick to call Montgomery's case an isolated act.

His crime caused more than $110,000 in direct damage and another $164,000 in related costs stemming from the plant's two-day shutdown, Assistant U.S. Attorney Pamela Foa said. The sentencing guideline range is 10 to 16 months for the lower amount, but could grow higher if Montgomery is held responsible for Boeing's total losses.

Lawyers will debate that point and the amount of restitution he owes before his Jan. 5 sentencing.

Neither Montgomery nor his father commented as they left the courtroom. Meehan also declined to comment.

Montgomery was making $19.10 an hour after 18 months on the job. Foa would not say if he had requested the job transfers for financial or other reasons.

"He knew on Saturday that he was going to be transferred. This was what he did on his way out that door," she said.