Project Sign Progress Report, 1948

FEBRUARY 13, 1948 187 THE AEROPLANE
flight of Kitchen's models. however. convinced Cedric Lee
that an aeroplane of such de~ign would be-a succes,. 11nd late
in 1910 he acquired the patents. At the same time, G. Tilghman
Richards, who was a qualifii:d aeron:iutical engineer, became ,
~uffic1ently interested in the mailer to give up a budding
engineering bureau in order to join Cedric Lee and 10 devote ·JUI· tl?,!i mhib energy 10 tbe idea of a ·• safety " aeroplane.
Tilghman Richards began with systemat ic experiment, on __.._
models and on large gJiders. Later, careful wind-tunnel test~
(including the o bservation of the pressure distribution) were
made by him in a :!-ft. tunnel he had constructed at East London
College and al~o in tunnels-of tile National Physical Laboratory.
The preparation of the design was, therefore, uncommonly
~-ardul for this early period of 1911 - 1914.
In o rder to ap(>reciate the intention~ for the development, the
following quota11on from a paper read by Tilghman Richards
in about 1912 is illuminating:-
... . . 1 he ve ry fnct of high lift occurring at small angles
rreans the provision of large area for l•nding speed resulting
in an inefficient altitude of the plane at high speed: and the
inherent instability of curved aerofoils means a continual
dependence on extraneou, controls carried at some distance
f_rom the wing by heavy and redundant Structure. . . . High
lift at small angles il> u~eles~. likewise high lift/ drag ratio at
,mall an,les, and what is required is the reversal of the normal
type of hft c urve i:iving little lift •lit small angles with low value
of the lift/ drag ratio for landini. . . ."
Seen from our pre.sent state of knowledge and development,
a nd facing the burning problems of personal aircraft for the
man in the street. it wo uld seem that this opinion is a very
i;o~ argument for further experimentation along the lines
indicated.
_The. experience with _powered aeroplanes was at first beset
with disappointment~. Famine P_oint, Heysham, was apparently
no t a spot from which aeronauucal experimenters could derive
any comfort.
The original Kitchen biplane with a 50 b.h.p. rotary engine
was wrecked by a gale, during I 9 I I. before flight tests could
b~ m~de. After recort~truction some flight~ were performed
wtth 11 at Sho!eham ; for the pilot, but. unlucky for the
precious craft. After havmg flown a large circuit on the first
attempt. the pilot noticed, when coming in to land that the
aeroplane was exceedingly tail-heavy and getting out ~f control
the elevator. bei!Jg insufficient. At about 150 ft. above th~
ground the inevttable stall took place: but the pilot managed
~~mehow to drop his mount upside down on to telegraph
wire~ and escaped without personal injury.
Wtth the reconstructed and improved monoplane many
s\iccessful flights were made by G o rdon England, N. S. Percival
-:'x:
- -'-
Fig. 6.-Huth annular biplane of 1909.
and Gordon Bell. Finally it came to i;ricf when flown by
Cedric Lee himself without previous training. After a good
fliaht he managed to put it into a river.
Another incident happened with a subsequent annular
monoplane: the elevator jammed anct broke in flight. The
aeroplane merely pancaked to the ground, again preserving
the health of i~ pilot, E. C. Gordon England.
These types in their final form had lateral control effected
by differential deflection of the elevators. It was realized that
this elevon control was not very effective for lateral manceuvres.
yet the lateral stability of the wing proved so great that the
provision of ailerons seemed superfluo us. The loneitudinal
stability was always satisfactory, once the centre of gravity was
properly located. Because of the great inherent · fore-and-aft
stability, a separate elevator was, at o ne time, located on top
of the vertical fin and permitted the fitting of special ailerons.
For directional control a vertical rudder was attached to the
stern of the fuselage at the trailing edge of the wing. A form
of tricycle undercarriage was employed.
- In respect of perfo rmance, the wind-tunnel tests indicated
that a better lift/ drag' ratio could be expected than with a
comparable conventionaf aeroplane., However, no co nclusive
evidence for this has, as,yet, been presented.
The third British monoplane of this type also had an 80 b.h.p.
rotary engine. but this time it was located aft and. further, drove
the airscrew by means of an extension shaft. Unlike its pre
d~cssors, ~~ dihedral was provided. and because of this the
flying qualities were found to have been greatly improved.
From early in 1914 until the outbreak of the 1914-18 War
this unco nventional aeroplane was frequently flown (mostly
by Gordon Bell): it was demonstrated before Winston
Churchill in the hope of securing orders from the Admiralty.
Altogether, 11,000 miles were flown in about 128 hours, a nd
eve~ people not previously trained as pilots were able to
fly 11. In Ma y, 1914. two such aeroplanes were being designed
for parlicipation in the Gordon-Bennett Race of 1915. When
the 1914-19 18 War terminated the work. it had clearly grown
far beyond the stage of an untried project and could have
well been termed a successful experiment with every prospect
of becoming a practical proposition.
In l?l~-10 Tilghman Richards succeeded in persuading the
Air Mm1stry 10 place a n order for a further experiRlental
aeroplane. But a week after communica1ing this decision
Major-General Bagnall-Wild, the promoter of the idea, retired,
and red tape killed an intelligent intention.
It is only fair to record that aeronautical progress has suffered
fr~m the failure to have this develop'ment continued. As
Tilghman Richards stated many years ago:-
.. There i~ no!hing myMerious about th~ annular plane.
It affords high ltft at large angles, ha~ no >urble point and
has ~ good lift/ drag . rati_o for wings with a body. ' The
!Tiachm~ was very fast in p,ght. for its day, and extremely slow
m lan~mg: and there bei!)g three dislinct regions of lift, one
a ptero1d and two pterygo1d on each half-wing. the movement
of the centre of pressure was a resultant of three distinct
regional movements; ,tnd with slight modifications could be
made 10 move in any desired manner witho ut affecting the
general efficiency of 1he plane."
As _mentio ned. th«: c!rcular shape for the wing is not in itself
~ dec1s1ve cha".\c1enst1c. ?reviously. in 1908, A. H. Edwards
invented the ring-type wing with rhomboidal or triangular
shape_ (Brit. Pat. Spec. No. 4519 of February, 1908). An
experimental aeroplane of this type, "The Rhomboidal,'' was
constructed and tested at Brooklands. It wa~ not s uccessful.
(To ~ conlit1u~d.)Fig 7.-Cedric Lee Monoplane No. 1 of TIighman Richards, 1912.NND 927545