A woman has described how she was left alone on an Air Canada plane after falling asleep during a flight.

The carrier is looking into how staff did not spot passenger Tiffani Adams who was then left on board after the plane landed.

The woman says she woke up cold and alone after flying from Quebec to Toronto earlier this month.

She was eventually spotted by ground crew after managing to open one of the plane's doors.

Ms Adams' friend, Deanna Noel-Dale, wrote on her behalf on Air Canada's Facebook page.

She says: "My flight home I got super comfy reading my book happy I scored my row all to myself (flight was about 1/4 full) I fell asleep probably less than halfway through my short 1.5 hour flight.

"I wake up around midnight (few hours after flight landed) freezing cold still strapped in my seat in complete darkness (I'm talking pitch black) as someone with and anxiety disorder as is I can tell you how terrifying this was".

Grounded Air Canada Boeing 737 MAX 8 jetliners parked on the tarmac at Vancouver International Airport | Image: Bayne Stanley/Zuma Press/PA Images

She says her phone lit up with missed messages and she then text her friend, Ms Dale, that she was "all alone on this cold dark plane" after waking up.

She says as she tried to Facetime her friend, her phone battery died.

She writes: "I'm trying to focus on my breathing and control my panic attack while I attempt to charge my phone by plugging into every USB port I could find" - which she said did not work, as the plane had no power.

"Since I can't charge my phone to call for help I'm full on panicking [because] I want off this nightmare".

She adds: "I found the walky talky thingys in the cockpit but they also don't work I can't radio for help.

"I was so overjoyed when I found a flashlight in the cockpit and I'm making some flashy SOS signals out the windows hoping someone sees me."

She says she then managed to get the main door of the aircraft open: "I hang out the door trying to get the attention of ground crew I can see Pearson's [Airport] lights but too far away I'm where the aircrafts park overnight there is no one around".

"When I see the luggage cart driving towards me I am literally dangling my legs out of the plane..he is in shock asking how the heck they left me on the plane".

She says the man then gave her a ladder dock and she jumped to safety.

"Air Canada called Monday and Tuesday both people again ask me to repeat what happened apologise for my inconvenience and say they will do an investigation [because] they have checks in place that should prevent people from being locked on the aircraft at night".

"I haven't got much sleep since the reoccurring night terrors and waking up anxious and afraid I'm alone locked up someplace dark", she adds.