HALIFAX -- Federal investigators have arrived in Halifax to piece together why a Boeing 747 cargo plane skidded off an airport runway Wednesday, leaving a trail of debris and sending four crew to hospital.

The SkyLease Cargo jet overshot Runway 14 just after 5 a.m. -- the third serious incident at Halifax Stanfield International Airport in 15 years, following crashes in 2004 and 2015.

Airport spokeswoman Theresa Rath Spicer said Flight KKE 4854 was arriving from Chicago in rainy conditions, and scheduled to be loaded with live lobster destined for China.

"It did land and then overshot the runway," Rath Spicer said Wednesday.

"There were four crew on board at the time. They were removed from the aircraft and transported to hospital with what are described as minor injuries."

She said it wasn't clear what caused the accident.

Larry Vance, an aviation analyst and accident investigator who spent 25 years with the Transportation Safety Board of Canada, said it appears the plane was landing with a strong tailwind -- something he called an "immediate red flag."

"Normally airplanes take off and land into the wind, that's just a standard procedure that's been going on since the Wright brothers," he said.

While it's possible to land with a tailwind, Vance said there would be little room for "deviations" such as a high airspeed or delayed touchdown.

Another potential factor could have been the rainy conditions, he said.

"It takes longer to stop on a wet runway. It could be they got into a situation we call hydroplaning."

A team of Transportation Safety Board investigators arrived at the airport Wednesday to gather information and assess the incident.

Board spokesman Chris Krepski said investigators will examine the aircraft and surrounding terrain, interview possible witnesses and crew members and take possession of the flight data recorders.

Vance said investigators will examine whether there were any mechanical issues with the plane -- in particular with the braking system or reverse thrusters.

The Halifax airport has two runways, and Rath Spicer confirmed that both were operational at the time of the incident.

It's the third serious incident at Stanfield in 15 years, but Vance said Halifax is a modern, sophisticated, well-equipped and well-run airport.

"There's no particular reason why Halifax would be singled out as being a hazardous place other than the fact that it's challenged by some environmental conditions," he said.

The badly damaged plane was sitting Wednesday on a slight incline far off the runway and within about 50 metres of a fence that marks the perimeter of the airport boundary. Two of its engines appeared to be attached but were heavily damaged, while two other engines were sheared off completely.

"The motors were tore off and the wings were cracked off. And it looked like halfway through the plane it was broke in half," said John Fudge, one of many people who came to look at the plane before police sealed off a nearby road.

"It was kind of crazy to see that, but at least nobody got hurt ... I figured it would have been worse than what it was, but luckily it's not."

An aluminum ladder trailed from an open main door near the front of the aircraft.

The airport activated its emergency operations centre and suspended all flights after the crash, but the main runway was reopened shortly after 8 a.m.

There were many delays in arrivals and departures, and some flight cancellations.

In August, Stanfield airport announced SkyLease Cargo was operating two flights a week for First Catch, a Chinese-owned seafood freight forwarding company.

It said SkyLease's 747 aircraft had the capacity to carry up to 120 tonnes of Nova Scotia seafood to Changsha, the capital of China's Hunan province.

Officials with SkyLease weren't available for comment Wednesday, while First Catch staffers refused to comment.

According to Airfleets.net, the Boeing 747 first flew on Feb. 28, 1997, and was previously owned by Singapore Airlines before flying for SkyLease in 2017.

Flightradar24.com said the plane had flown to Anchorage, Alaska, and Changsha on Monday.

According to the Air Line Pilots Association, cargo planes have an accident rate seven times higher than passenger planes.

Two other planes -- including one cargo jet -- have crashed while attempting takeoff or landing at the Halifax airport since 2004.

A passenger plane crashed during a blizzard on March 29, 2015, injuring 25 people. Air Canada Flight 624 bounced into the air and crashed near the runway threshold before careening along the tarmac. Federal investigators blamed approach procedures, poor visibility and lighting.

On Oct. 14, 2004, a British-based MK Airlines 747 went down just beyond the runway during takeoff, killing seven crew members. The Boeing cargo aircraft dragged its tail before breaking up and bursting into flames in a wooded area. No one survived.

The Transportation Safety Board found that fatigue and inadequate software training led the MK Airlines crew to enter incorrect information and caused the plane to set the throttles too low.

Rath Spicer said the earlier incidents were on a different runway, and deflected questions about any similarities among them to investigators.

"We are very proud of our safety record," she said. "Obviously, safety is our number 1 priority and we are now focused on resuming our operation, ensuring the safety of our passengers and working with the officials to determine how we can assist with the investigation."

Chris Praught, a spokesman for the Air Canada Pilots Association, said his thoughts were with the SkyLease Cargo flight crew.

"We are following this issue carefully as we do with any incident to determine what safety lessons can be learned, such as any potential impact of fatigue given that this was an overnight operation," he said in an email.

-- With files from Alison Auld, Brett Bundale, Keith Doucette and Holly McKenzie-Sutter