Passengers taking off and landing at New York’s LaGuardia airport have a front row seat into the twisted wreckage of Air Canada Express Flight 8646, which still lies by the airport’s Runway 4.

The mangled wreck, which was carrying 72 passengers and four crew members from Montreal when it collided with a fire truck late Sunday, will remain where it came to a stop until investigators from the National Transportation Safety Board (NTSB) have completed their work.

NTSB chair Jennifer Homendy said Runway 4 may remain closed for days as investigators sift through a “tremendous amount of debris.”

On Tuesday morning, footage showed Spirit Airlines and United flights passing by the wreckage, in full view of passengers. The bright yellow aircraft was seen wheeling by the scene, with debris dangling from the gnarled regional jet alongside the destroyed, overturned fire truck.

The cause of the accident is still under investigation, but the air traffic controller had given clearance bothe for the plane to land and the fire truck, which was attending another emergency, to cross.

Both pilots — Antoine Forest and Mackenzie Gunther — died as the plane’s nose hit the middle of the fire truck around 11:38 pm. The impact obliterated the nose and cockpit and one flight attendant, Solange Tremblay, was ejected while strapped in her jump seat. Miraculously she survived with injuries requiring leg surgery.  

In total, 41 people were hospitalized including passengers and crew.

Sherrie Katanach, 40, flew into LaGuardia on an American Airlines flight from Chicago O’Hare airport and saw the wreckage.

“At first I was just shocked at the proximity, it was right there. It’s shocking, you land and it’s the first thing you see when you’re on the tarmac.

“It’s incredibly sad and scary. Especially since we’re flying in here! It was scary for us,” the director of Communications for Native American Boarding School, New Mexico, told The Post.

Attorney Sherman Criner was heading back from a longshoreman convention in New Orleans when he and his wife, Wendy, were stranded at LaGuardia due to travel chaos over the weekend.

Fearing another insane wait on the TSA line, they decided to remain in LaGuardia and slept on the terminal floor for two nights. Outside the window, they could see the Air Canada flight smoldering.

“That was unbelievable to me,” Criner, 59, told The Post. “I figured they would get that off the runaway as quickly as possible, but from the plane you could see it still sitting there.” The couple finally made it home to Wilmington around noon Tuesday.

“I just kept thinking, at least we’re going to get home. There’s people on that plane who are never getting home. It really puts things into perspective,” he said.

Hundreds of flights have been cancelled at a time when the nation’s airports have been thrown into chaos thanks to a partial government shut down that has led to staff shortages, affecting tens of thousands of airport security screeners.

LaGuardia has resumed limited operations utilizing its other runway. The notoriously compact, congested, and tricky (for pilots) airport only has two runways — Runway 4 was named at time when there were four — which intersect.

At roughly 7,000 feet, LGA’s runways are also shorter than typical major hub runways, which often exceed 10,000 feet, such as those at nearby Newark or JFK. The intersecting layout at LaGuardia is also less efficient than parallel runway systems like at most major US airports.

It also means many passengers taking off and landing this week will pass right by a horror show — making things worse for nervous fliers.

At a press conference Tuesday afternoon held at LaGuardia’s Terminal B, Homendy told reporters there were two personnel in the control tower at the time performing multiple roles — which is standard procedure at LaGuardia for the midnight shift they were working.

“I would caution pointing fingers at [air traffic] controllers and saying distraction was involved. This is a heavy workload environment,” she said.

The Air Canada flight was going 103 miles per hour when it collided with the fire truck, FlightRadar24 told The Post on Tuesday.

The FAA is probing whether a LaGuardia Airport air-traffic controller may have been distracted at the time of the crash, a report said.

The potential distraction involved a nearby United Airlines flight that aborted its take-off because a mysterious odor had sickened crew members, according to the New York Times.

An air-traffic controller had cleared a Port Authority fire truck to respond to the United flight by crossing the runway as the Air Canada jet was landing on the same stretch, according to the report.

Heartstopping audio posted on the site LiveATC.net revealed a tower crew realized too late that the truck and plane were on a collision course.

“Stop, stop, stop, stop!” a controller pleaded with the truck over the radio. “Truck 1, stop, stop, stop! Stop, Truck 1! Stop!”

A controller can be heard later in the audio admitting, “I messed up.”

Homendy said Tuesday on Fox and Friends it was “too early” to solely blame the air traffic controller overheard in the audio and that the agency was investigating “multiple failures.”