Project Sign Progress Report, 1948

THE
AEROPLAtlE18S IFEBRUARY 13,
194&
#
The Biolo!
of
the Flying
Sa
f
cer
- I
The Story
of
Low Aspect Ratio Aircraft
By A. R. Weyl, A.F.R.Ae.S.
o t
her
hand. the U.S. Air Force
co
nsidered the matter seriQU\
SEVERAL MONTHS
AGO
pe
o ple o n
both
side
..
of
the enough
to
warrant inve
..
tigations into the incidenis which had
Atlantic rushed into print wnh cl
aim
s of having ob~erved
queer
saucer-shaped aircraft which new very fast . Some main been reported.
ta
ined, indeed. tha t they had s
een
,qua
dron\
of
, uch mysterious In the meantime. the
occur
rence
of
Flying Saucer\ ha
..
ceased
ob{"ccts; others described vividly how these celestial saucers v.ere to be
new\. P resuma bly. the~ have all landed. [A new
cr
op
ab
e
10
descend vertically. All agreed
on
the
\aucer-hl.e , hapc. w
aa1lplane movement proved that slender wings were a necessity
fo r soaring. designer, began striving a fter .. good .. aspect ratios.
The
theory blinded their eye~ agains, the poss1bili11es
of
other
than convenrional wings. T
hi~.
hO\\Cver. was
not
the fault
C"f
the
theory.,\\
Prandtl soon sho\\ ed its restrictions.
We have now come 10 reconsider the matter
of
wing sh
ape
in an objective way.
as
it is quite possible
that
aircraft design
is approaching a cul-de-sac
~o
long
as
it retains
it~
bias in
--6----
~
Apttro.l
1
L- I._ ' _
°'
,
-r.:--i,
I c
6)
-
___
__
,_ _
'°'
_1
___
___,
==~
(b
OCl5S • stCTIO!'I
\
,pa"
C chor4
t \
)(•-,lod
a,u
Fig
. 1
.-"
Turbine flying mach
ine"
(project) of the Munich
engineer Gustave Koch, 189311894. Tailless monoplane of SquHC'
low aspect ratio. propelled by a ducted fan. A
SO
h.p. ...~ ,steim engine
wu
deemed sufficient for th is flying motor
car. The design of the duct shows intelligent anticipation. L ...._______.
AR
• 0-1
I-
b ,
__j l t tFig. 2 (Right).- Definitlon of the aspect ratio of an aerofoil.
The arrows signify the direction of the air flow against the t t twing. The terms pteroid (feather-like) and apterold have
been introduced by F. W . Lanchester.NND 927545