NPL Research Biplane Design

https://www.flightglobal.com/pdfarchive/view/1935/1935%20-%201431.html?search=physical
 
Thank you my dear Schneiderman,

and I think it's the same design,was there any other research aircraft to NPL ?.
 
This was not an actual aircraft, it was part of the NPL wind-tunnel research with models and aerofoils. A summary (vol 1) of all published NPL and RAE research each year can be found here

http://aerade.cranfield.ac.uk/arcar.html

However...I cannot yet find the research report that is refered to in the article in Flight and copied in L'Ailes.
 
As the report does not appear to be part of the ARC funded R&M series the work undertaken by the NPL would probably have been commissioned and funded by one of the aircraft companies. A search through patents may help identify the origin of the project.
 
Schneiderman said:
As the report does not appear to be part of the ARC funded R&M series the work undertaken by the NPL would probably have been commissioned and funded by one of the aircraft companies. A search through patents may help identify the origin of the project.

Maybe we will find something.
 
A-HA!!
This was the work of N.P. Irving, an aerodynamicist at the NPL. The configuration was designed to give good behaviour at low speeds and near the stall.
In 1935, this configuration was used by Airspeed for one version of the AS.27, a slow-speed coastal patrol and general purpose aircraft.
The below from Putnam's 'Airspeed', page 152 :-

"AS.27
The designation AS.27 was orginally given to a project intended to meet a
requirement for a slow-speed coastal patrol and general purpose aircraft.
Designed in 1935, this was a highly unconventional single-engined biplane
with its wing arrangement following principles developed by H. B. Irving,
the National Physical Laboratory aerodynamicist, intended to give the
aircraft a wide speed range and good slow-speed stability.
At about this time there was also a requirement for a ‘special defence’
aircraft which,flying in or above cloud, would trail a winched-out cable or cables,
possibly carrying high explosive, to menace enemy bombers. The idea was
that these aircraft would be flown by second-line pilots, although at that
time no plans had been made to recruit and train such pilots. The largely
abortive Civil Air Guard had yet to be formed, and the far from abortive
Air Transport Auxiliary was not formed until war was imminent in 1939.
Another, very different, version of the AS.27 was therefore designed
late in 1936. This, a characteristically handsome single-engined high-
wing cabin monoplane, was considered likely to be more suited to the
‘special defence’ role, though design and development work on the Irving-
wing biplane continued. Orders were placed by the Air Ministry for two
prototypes of the AS.27, and RAF serial numbers K8846-8847 were
allocated, but neither aircraft was built.
The Irving-wing AS.27, to be powered by a 225 hp Wolseley Aries, or
250 hp Wolseley Scorpio, both nine-cylinder radials, was a heavily
staggered biplane, with the upper wing sharply tapered and with the
lower wing, of more conventional planform, having a marked dihedral
and forward sweep. A wide split-axle undercarriage with long-movement
oleos was fitted. The cockpit was enclosed and the pilot would have had
a good view forward and downward ahead of the lower wing. The estimated
speed range of this version of the AS.27 was 43-121 mph.
The monoplane special defence project was to have been powered
by a 350 hp Armstrong Siddeley Cheetah IX seven-cylinder radial, in a
helmeted cowling. It was a clean high-wing cabin monoplane with single-
strut bracing and cantilever undercarriage legs with internally sprung
wheels. The engine was low-slung so that the single centrally-seated pilot
would have had a good range of forward and downward view. The wing
was tapered, with slots ahead of the ailerons and plain flaps inboard. The
tailplane was a cantilever structure."

Image source also Putnam's 'Airspeed', page 153. Apologies for the quality, the original has very fine lines, which don't scan well.


cheers,
Robin.
 

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Good man! I knew the layout was familiar but couldn't recall where I had seen it.
 

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And here is the patent I knew had to be out there, GB450676, Henry Braid Irving 1934.
 

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I remember, many years ago, there was an article on Airspeed projects in 'Aeroplane Monthly', and the shape stuck in my mind. I still have that article, somewhere . . . it was easier to pull the Putnam.
Drifting OT, the monoplane AS.27 is so American looking, if it wasn't for the 'Airspeed' fin and rudder, one would think it was a Monocoupe, a Luscombe, or even a Cessna . . .

cheers,
Robin.
 
Better scan from Putnam's 'Airspeed'.
<edit> not happy with the Mustek scan, I plugged in my old Canon scanner for better results.
 

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Cheap Mustek A3 scanner set at 600 dpi.
 
Your copy must be better printed than mine, even at 1200 dpi, I couldn't get the fine lines to pick up . . .

cheers,
Robin.
 
My copy is a 1970 edition on semi-glossy paper. Later Putnams were printed on different paper.
 
That explains it, my copy is the later edition, printed on bond paper, and with lower print quality . . .

cheers,
Robin.
 

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