[ak267]

lands and ascends like a helicopter with its central rotor but once in the air it activates the jets.

[Aliska]

That was the idea; I didn't know the jets were actuated after takeoff. Four jets would provide stability (if they all fired).

tophat, that would be another practical application for the jets; I remember specifically the acronym JATO and it was for planes like on ship runways or on jungle airstrips, short runways.

[Aliska]

I think I conflated JATO with your concept. On google images, JATO was used for non-vertical takeoff jet planes. One design for Blue Angels uses it, but it was in the 80's.

I shouldn't chime in when I only have a dim memory of new technology years ago. I never saw an engineering drawing for it.