Ducted prop spinners: what was the point/purpose of these?

[Merv_P]

http://www.flightglobal.com/pdfarchive/view/1948/1948 - 1659.html

I came across this picture of a Tempest, just postwar; the article mentions the ducted spinner without giving an explanation. To an untrained eye, it looks like a sort of halfway house between a conventional propellor and a turboprop. Is that right, or does it have a different purpose?

 

[Rickshaw]

They were a fad for a time to try and improve the streamlining and reduce the drag. The idea was to duct air through the spinner into the engine (usually a radial but occasionally an inline with an annular radiator) and thereby reducing drag by eliminating extra scoops for the radiators. They invariably didn't work, as far as I'm aware. They were tried on various American, German and British aircraft (not aware of any Japanese ones).

 

[Jemiba]

AFAIK, a problem always encountered was insufficient cooling, as was with
the first Fw 190 prototype ( see for example here : http://en.wikipedia.org/wiki/Image:Fw190V1.jpg).

 

[Antonio]

From the US side, the Curtiss XP-42

http://www.nationalmuseum.af.mil/factsheets/factsheet.asp?id=2244

 

[frank]

That's not a ducted spinner, tho.

From the US side, the Curtiss XP-42

http://www.nationalmuseum.af.mil/factsheets/factsheet.asp?id=2244

 

[Antonio]

Ups, sorry Frank, you're right

According to Enzo Angelucci's "The American Fighter" (page 169)

"Curtiss engineers installed a P&W R-1830 engine with an extremely aerodynamic cowling and with a large spinner covering the propeller hub. The air intake for the radiators was located under the engine, the inlet for the carburetor being above it"

 

[Justo Miranda]

Northrop A-17 samples with ducted ans streamlined spinners

 

[Justo Miranda]

Curtiss XP-42 cooling system

 

[Justo Miranda]

Here some Focke Wulf samples...

 

[Justo Miranda]

Bristol M.1C and Hawker Tempest MkV NV768

 

[Justo Miranda]

Renard R.37 cooling system

 

[Justo Miranda]

Focke Wulf 187 ducted spinners

 

[Justo Miranda]

Arado Ar 240 A-10,Messerschmitt Bf 109 H and Me 209 V4

 

[Jemiba]

Just found today in InterAvia 12/1948, a 5-engined B-17 with
at least one ducted prop. It was used as a testbed for the Wright
XT-35 Typhoon engine.