A “chilling” handwritten letter has been discovered more than 400 days after it was penned, poignantly summarising the mammoth toll of the coronavirus pandemic.

Delta Airlines pilot Chris Dennis left a note inside the cockpit of Delta ship 3009 after parking it in the Victorville airport in the California desert on March 23 last year.

It was one of hundreds of planes, including several owned by Qantas, which were grounded when Covid-19 immobilised the population and forced widespread travel bans.

Last week, the Delta plane was assigned to First Officer Nick P, who was tasked with “waking up” the plane for the first time in more than a year.

“One thing he didn’t expect to find was Chris’ letter, tucked away on a tray table in the flight deck,” Delta said.

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The letter’s 57 words “captured so much of the uncertainty and emotion we all felt in March 2020” a post to the airline’s Facebook page read.

“Hey pilots, it’s March 23rd and we just arrived from MSP [Minneapolis – Saint Paul International Airport]. Very chilling to see so much of our fleet here in the desert,” Mr Dennis’ letter read.

“If you are here to pick it up then the light must be at the end of the tunnel. Amazing how fast it changed. Have a safe flight bringing it out of storage.”

The letter “underscored the gravity of the trip”, according to the airline, which announced the plane was being prepared to “take to the skies again” after 435 days.

Mr Dennis described seeing the hundreds of aircraft parked for storage as “chilling, apocalyptic and surreal” in a post he shared to Facebook the day after he left the letter.

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“Today was a day I will remember for the rest of my life. A trip opened up to bring a Delta A321 to Victorville, CA for storage. I had no idea what I would see or the emotions I would feel,” he wrote.

“Chilling, apocalyptic, surreal … all words that still don’t fit what is happening in the world. Each one of these aircraft represents hundreds of jobs, if not more.”

In two weeks of mandatory quarantine at the time, his post served as a stark reminder of how aggressively the virus took hold of life as we knew it.

More than 400 people agreed with an unofficial petition calling for the A321 to be given a “custom paint scheme” to symbolise the “spirit of America” or “hope”.