Elon Musk says he is close to working out how to build an electric jet which would take off and land vertically. The Tesla boss revealed his plans during a question-and-answer session at the Hyperloop Pod competition in Texas.

Such a plane may sound impossible, but Musk has a strong track record for turning concepts into reality. He has brought electric cars into the mainstream with Tesla, is experimenting with reusable space rockets at SpaceX, and is now involved with Hyperloop, his plan for a 700mph train.

Speaking at the Hyperloop event, Musk answered the question of what his next "great idea" will be, by saying: "I've been thinking about the vertical-take off and landing electric jet a bit more. I think I have something that might close. I'm quite tempted to do something about it." Musk's comments were initially met with quiet laughter, then cheers and applause as the audience realised he was being serious.

Naturally, the next question fired at Musk was "How do you convince people that your ideas aren't crazy?", to which he answered: "In starting SpaceX, they definitely thought I was crazy. One of my best friends compiled a long video of rockets crashing and made me watch the whole thing. Other friends involved in a rocket startup said it was a terrible idea, and I thought we had a really tiny chance of succeeding anyway, like 10%... and it was very close [to failure] but I think, ultimately, seeing is believing... that's what convinces people."

History repeating

This is not the first time Musk has talked about building an electric jet. During an interview with Marketplace in October 2015, Musk said: "I do like the idea of an electric aircraft company. I do think one could do a pretty cool supersonic, vertical-take off and landing electric jet. That would be really fun."

When asked if he was just making things up, Musk said: "No, I have a design in mind for that, but I have too many things on my plate to do, and then of course there is the Hyperloop."

In 2014, Musk also mentioned his electric plane ideas during an interview with the Massachusetts Institute of Technology (MIT), when he said he was "toying" with the concept, adding: "I would love to do it, but I think my mind would explode."

Musk's comments come in the same week which saw budget airline EasyJet announce it is looking at producing hybrid electric airliners. The plans describe a kinetic energy recovery system (Kers) similar to that used by Formula One cars, where energy created by braking when landing would be stored in a battery and used to run and even taxi the plane without using its jet engines.