"I thought that looks pretty intersting. As we drew up next to it we asked to go to the right to get around it. You don't want to fly through one of those. The turbulence would be horrifc. That'd be bad news.
"We were 18,000 ft because the turbulence was estimated to be around 14,000 ft. Good thing we did because this was building and building and building.
"The picture shows a good sense of scale, but when you're there at nearly 20,000 ft yourself it just kept on going up.
"I've seen some remarkable cloud formations but nothing comes close to that."
Beckett captured the lenticular cloud in a second view as he "approached it from the north".
He tagged in WeatherWatch.co.nz to the stunning photo.
WeatherWatch chief executive Philip Duncan tweeted that that the image and cloud formation were "mind-blowing" and "unreal".
"It's absolutely mind blowing, Geoff. Unreal! Each layer so neatly and perfectly stacked. I've never seen a photo like this in my life!"
"This incredible lenticular cloud was spotted over New Zealand's South Island region of Otago over the weekend," WeatherWatch wrote on its website.
"Lenticular clouds are clouds that don't move and form mostly in the troposphere. A westerly breeze over the ranges below helped build this.
"They are often comparable in appearance to a lens or saucer and we often see smaller 'UFO'-type clouds in New Zealand, especially in eastern areas like Otago and Canterbury when the westerly quarter winds are just right."
