KALISPELL, Mont. - A jury trial is set to begin May 21 for a Canadian man accused of crashing a rented airplane into a Montana lake and leaving his girlfriend to drown 24 years ago.

District Judge Stewart Stadler will preside. The trial is expected to last five days.

Jaroslaw (Jerry) Ambrozuk pleaded no-contest Feb. 1 to felony negligent homicide in the 1982 death of Dianne Babcock, 18. But he unexpectedly changed his plea to not guilty at a March 7 sentencing hearing before Stadler, prompting the trial.

Prosecutors had agreed under a plea deal to recommend 10 years of unsupervised probation, which would have freed up Ambrozuk to face immediate action on U.S. passport-fraud charges in Texas.

But a probation officer testified at the sentencing hearing Ambrozuk likely would be deported for the passport violation and the United States would have no jurisdiction over him in Canada.

Given that "significant change in circumstances" and opposition by Babcock's family, Flathead County Attorney Ed Corrigan said he no longer considered the plea agreement appropriate and gave Ambrozuk the opportunity to change his plea.

Stadler also said he would have found the 10-year probation sentence inappropriate.

Considering Ambrozuk already has spent six months in jail since he was found living in Texas under a different name, Corrigan asked for a trial to begin within 80 days.

Ambrozuk is accused of deliberately flying a small rental airplane, in which Babcock was a passenger, into Little Bitterroot Lake, then leaving her to drown as he escaped.

He told a friend about the crash but did not report it to authorities before he disappeared for the next 24 years. The plane was found a month after the crash in more than 73 metres of water.

Ambrozuk maintains he and Babcock were teenage lovers looking to run away from their homes in British Columbia and start new lives under new identities in the United States.

He said they planned the escapade together and he was devastated when he was unable to free her from the plane before he swam away.