Sunwing Airlines is defending its scheduling in a case where a pilot showed up for the second flight of his 11-hour shift so drunk that he appeared to fall asleep in the captain's chair. But a pilots' group says the scheduling practice raises concerns.

Miroslav Gronych pleaded guilty this week to having care and control of an aircraft with a blood alcohol level over .08 after being arrested at the Calgary airport on Dec. 31, 2016.

According to an agreed statement of facts presented in court, Gronych flew into the Calgary airport at 12:48 a.m and was supposed to report back at 6 a.m. for a 7 a.m. flight that was scheduled to make stops in Regina and Winnipeg before continuing on to Cancun, Mexico.

Gronych was scheduled to finish his shift after the plane stopped in Regina.

Federal aviation regulations require that pilots have the opportunity for at least eight hours of sleep prior to reporting for flight duty at the beginning of a shift.

In this case, though, Sunwing said Gronych's duty had begun the previous night and included two separate flights, so the roughly six-hour break between them fell within the rules.

But Greg McConnell with the Canadian Federal Pilots Association (CFPA) said "split duty" shifts like these raise concerns about pilot readiness.

"When I saw that … it raised my eyebrows immediately," he said of the duration between Gronych's scheduled flight times.

The CFPA represents professional pilots whose duties include aviation inspections, flight testing of pilots, certification of operators and the development of operating standards.

Fly, wait at hotel, then fly again

Sunwing declined an interview but, in an email, the company said Gronych's scheduling fell within Transport Canada guidelines.

The shift began when he reported for duty at 10:25 p.m. on Dec. 30 in Winnipeg and flew to Calgary, arriving just before 1 a.m. on Dec. 31.

"Sunwing then arranged a room for him at the Delta Calgary Airport Hotel where he was to wait until his next scheduled flight later that same morning," spokesperson Jacqueline Grossman said in the email.

But Gronych was late reporting for the 7 a.m. flight, according to the agreed statement of facts.

At 6:50 a.m., the flight's co-pilot called Sunwing's operations centre, who then contacted Gronych. He said he was lost in the airport and struggling to find the right gate.

Gronych eventually arrived at the correct gate at 7:05 a.m., court heard, after passengers had already boarded the plane.

Signs of impairment

At this point the co-pilot observed what he described as obvious signs of impairment — slurred speech, staggering and difficulty in accomplishing simple tasks like hanging up his jacket. He then took Gronych off the aircraft to tell him he wouldn't be flying the plane.

When the co-pilot then called Sunwing's operations centre to update them on the situation, court heard that Gronych then returned to the flight deck, sat in the pilot's chair, and appeared to fall asleep.

He later left the aircraft voluntarily and was arrested by police at 8:08 a.m.

It is against the law for pilots in Canada to have consumed any alcohol within eight hours of flying.

Individual airlines often have even stricter rules, including Sunwing, which Grossman said has a "a zero tolerance policy" on any alcohol consumption within 12 hours of duty.

A Sunwing spokesperson has said the airline's scheduling of Gronych that day fell well within Transport Canada guidelines. (iStock)

Had Gronych completed his shift, Sunwing said he was scheduled to arrive in Regina at 9:25 a.m., where he would have ended his shift.

He was not scheduled to continue on to Cancun.

"It is important to note that Gronych was continuously on duty throughout the entire 11 hour and 15 minute period, which abides with Transport Canada's guidelines stating that a duty period cannot exceed 14 hours," Grossman said.

'You don't want us falling asleep'

While in Gronych's case the main concern was the pilot's impairment by alcohol, McConnell said double-flight shifts create the possibility for fatigue-related risks as well.

"In order to be effective, you have to be alert. You have to be aware of your surroundings," he said.

"For the same reason you don't want to fall asleep driving your car, you don't want us falling asleep when we're flying the airplane — it's basically that simple."

Transport Canada declined an interview request.

"As the case of the Sunwing pilot is currently before the courts, it would be inappropriate for Transport Canada to comment," a spokesperson said in an email.

Canadian Aviation Regulations require airlines ensure flight crew members are provided "the minimum rest period" prior to reporting for duty.

That minimum rest time is defined as "a period during which a flight crew member is free from all duties, is not interrupted by the air operator or private operator, and is provided with an opportunity to obtain not less than eight consecutive hours of sleep in suitable accommodation, time to travel to and from that accommodation and time for personal hygiene and meals."

After pleading guilty to the impaired charge on Tuesday, Gronych immediately began serving a jail sentence. He is due back in Calgary court on April 3 to learn the length of his sentence.

The Crown is recommending a one-year sentence while his defence lawyer is seeking a term of three to six months.