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.
