• Version
• 105 Downloads
• 1.54 MB File Size
• 1 File Count
• April 20, 2017 Create Date
• April 20, 2017 Last Updated

National Advisory Committee for Aeronautics, Research Memorandum - Wing-Flow Tests of a Triangular Wing of Aspect Ratio Two - I; Effectiveness of Several Types of Trailing Edge Flat-Plate Models

The problem of applying controls to los—espect—rotio wings of
triangular plan form has been investigated. by means of the NADA
wing—flow method. using parallel—sided models having sharp leading
and trailing edges. The controLefi‘ectivenessparameters dm/dbf
and. dam/lief were determined for CE = 0 in the Mach number range
from O. 50 to 1.10. Const-nt—chorfl. and constant—percent-Chord.
trailing—edge flaps, and. triangular droopei—tip flaps were tested.
on a basic plan form of aspect ratio two, and. semiverter angle of
26. 6°. In all cease the flap area. to total—area ratio was 0. 20.
The test Reynolds umbers varied from 500, 000 to 1,300, 000.

The low—speed. results suggested that the inboard. portion of
the trailing edge was the most effective area. for the location of
e. lift~producing flap—type control. At a. Much umber of 0.50 the
effectiveness of the constant—percent—chord flap was only about
10 percent less than that measurei elsewhere in two-dimensional
tests of o plain—flap straight—wing coinbinntimi having en
mar. 65—210 airfoil section.

Neither the basic plan form nor any of the control Sin-feces
exhibited any critical stick—fixed characteristics in the tronsonic
speed. range within the range of norml~force coefficients tested,
5:0.)4-0. The flap effectiveness, both pitching—noment and lift——
producing, cropped. to about half the low—speed. values near a. Mach
number of 1.0 and. then began to recover. , The pain—fort: normal—
force curve slepe and. the location of the aerodsnrmic center did.
not very appreciably with Mach number. The deflection of a consmnt~
chorcl flap was slightly destabilizing but did. not affect the lift-—
curve slope.

The lift-producing effectiveness_and planeform-characteristics
of a #50 swept—back constant—chord. flap on a modified plan form of
the same aspect ratio and vertex angle Were also measured and are
presented in the report.