Tailsitters

[Scott Kenny]

Here might be where rockets might be useful to lift the tail sitter just enough that jets don't injest debris like branches?

Lots more damage to wherever they're taking off from, though.

 

[publiusr]

Weren't there some plans for a jet to surround the rocket and have a common exhaust? Not quite a tractor rocket but perhaps enough to limit blast effects?

I have often thought about "jacketed" thrust streams where colder exhausts buffer nozzles from a hotter, inner-core stream...

 

[Scott Kenny]

Weren't there some plans for a jet to surround the rocket and have a common exhaust? Not quite a tractor rocket but perhaps enough to limit blast effects?

I'm not aware of any, but that doesn't mean they don't exist.

I have often thought about "jacketed" thrust streams where colder exhausts buffer nozzles from a hotter, inner-core stream...

That's usually done to increase total mass flow, as a ducted rocket.