The aerodynamic performance of a multi-element
high-lift system has a critical influence on the
direct operating cost of a subsonic civil transport
aircraft. A thorough understanding of the
aerodynamic characteristics of these multi-element
aerofoils and wings allows aircraft companies to
design and build more competitive aircraft with
high-lift systems that are less complex and lighter
for given high-lift performance or that have
improved lift and drag characteristics for given
system complexity and weight. Flight experiments on
NASA Langley's B737-100 aircraft have been conducted
to further enhance the understanding of the complex
flows about multi-element high-lift systems at
full-scale flight conditions. In this paper, an
overview of the flight program is provided, followed
by highlights of experimental results and
computational analysis. Measurements included
surface pressures on the slats, main element and
flap elements using flush pressure ports and
pressure belts, surface shear stresses using Preston
tubes, off-surface velocity distributions using
boundary layer/wake rakes, aeroelastic deformations
of the flap elements using an optical positioning
system, and boundary layer transition detection
using hot-film anemometers and an infrared imaging
system. Boundary layer transition measurements on
the slat using hot-film sensors are correlated with
the flow visualisation results from an infrared
imaging technique. Extensive application of several
computational techniques and comparisons with flight
measurements are shown for a limited number of
cases. This program has generated an extensive set
of data, much of which are still being analysed.