Rotavion XR-62 ducted-fan VTOL aircraft of 1960s

Hi,

here is a real project for Rotavion,it was XR-62 ducted-fan VTOL
aircraft,they began its mock-up during the early of 1962s.

http://books.google.com.eg/books?id=j98DAAAAMBAJ&pg=PA216&dq=ducted+fan+design&hl=ar&ei=taUYTObiA4rW4gaJoJnpCw&sa=X&oi=book_result&ct=result&resnum=15&ved=0CGsQ6AEwDg#v=onepage&q=ducted%20fan%20design&f=true

More of the same:

I'm not a 100% sure, but I think McDonnell Douglas eventually ended up with the rights to this particular technology.

It was General Electric that ended up building the tip-turbine-driven lift/cruise fan (ca. 1963-4) that was used in, among others, the Ryan XV-5A "Vertifan," a very successful demonstrator. Looking through NASA reports on lift/cruise fans and aircraft that use them, it looks like McDonnell-Douglas did a lot of work on developing aircraft configurations to make use of this type of machinery. Most of the relevant reports are available on the NASA Technical Reports server.

piolenc said:

It was General Electric that ended up building the tip-turbine-driven lift/cruise fan (ca. 1963-4) that was used in, among others, the Ryan XV-5A "Vertifan," a very successful demonstrator. Looking through NASA reports on lift/cruise fans and aircraft that use them, it looks like McDonnell-Douglas did a lot of work on developing aircraft configurations to make use of this type of machinery. Most of the relevant reports are available on the NASA Technical Reports server.

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Thanks piolenc, and welcome. Yes, I have browsed through dozens of NASA reports on the subject, and the amount of research that was done on VTOL in general, and lift-fan technology in particular, is quite impressive, considering the technology never found an application in any production item.

Which begs two questions (if you don't mind):
- Why didn't this technology find an application?
- What are the benefits of a single large fan over multiple smaller lift-fans?
- How does one ensure smooth airflow into the top of a lift fan at varying speeds (might be part of the problem)?

I was always fascinated by this tech as a kid (well, mainly shrouded helicopter blades)

Hi,

Avimimus said:

Which begs two questions (if you don't mind):
- Why didn't this technology find an application?
- What are the benefits of a single large fan over multiple smaller lift-fans?
- How does one ensure smooth airflow into the top of a lift fan at varying speeds (might be part of the problem)?

I was always fascinated by this tech as a kid (well, mainly shrouded helicopter blades)

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Can't answer the first question definitely, but one of the problems with tip-driven fans is the amount of space taken up by ducting in the aircraft. With distributed electric transmission that problem disappears. The Rotavion, which is hub driven like a helicopter, had an advantage, particularly at the time. Unfortunately, Ben Kaufman died, and the project died with him.
Single fan is better because larger is usually more efficient than smaller (clearance volumes are smaller in proportion), larger fan in Rotavion uses nearly all the wing area, etc.
Smooth airflow is a problem during transition, and if Kaufman had got to the point of testing a prototype a lot of work would have had to be put into that. That said, I think it can be solved - for example by staging the closing of the top louvers.

hesham said:

Hi,

Renny Lopez - The project XR-62 "Rotavion" published in... | Nose art, Popular mechanics, Tech info

Feb 25, 2016 - The project XR-62 "Rotavion" published in the Popular Mechanics August 1961, article author by Thomas E. Stimson, Jr

www.pinterest.ch

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My Parents actually invested in the original Rotavion Company in Santa Monica, California. They went to see actual demos of the aircraft. I thought this company went out of business? Does anyone know if the original stock holders lost all their investment money? Robert Birkenes, Boca Raton, Fl.