Aerospace Research - ISTC Funded Projects 1994-2009

An integrated analysis was made by separate
directions:
– ascertaining a rational aerodynamic airframe
configuration, including rational wingplan,
shapes of airfoil sections and other airplane
components, such as units of control and trim,
with the use of up­to­shape numerical methods
of aerodynamics;
– development and manufacturing of aerodynamic
models as well as a drained wing
compartment, ejector suction system, air
intake simulator and nozzle for experimental
investigations of powerplant/airframe
interference;
– experimental tests in TsAGI wind tunnels
(T­102, T­106) aimed at refining take­off–
landing aerodynamic characteristics and
determining their achievable level more
precisely (Fig. 7);
– studies of the interference effect of the
propulsion unit mounted on the upper wing
surface, near the trailing edge, as applied to
airplanes with turbojet engine T­129;
– formulation of a rational airframe structural
concept on the basis of finite element methods,
analysis of stressed­strained state, stiffness,
and weight characteristics;
– exploration of possibilities to use the
structure elasticity and mass distribution for
enhancing the aerodynamic characteristics of
the airplane, its lift qualities, reducing the
aeroelastic aerodynamic center shift,
increasing control effectiveness and critical
flutter speed;
– formulation of recommendations on passive
and active reduction of wing bending moments
and increase in the load ratio;
– generation of controls with due regard for
their multifunctional application, selection of a
rational structure and parameters of the flyby­wire­control
system and active control
systems with consideration for the
requirements providing the comfort of
passengers and crew;
Enhancement of Flight Performance, Economy and Efficiency
– analysis of the agreement between the
requirements of aeroelstic stability of the
airplane and the automatic flight control in all
regimes;
– experimental studies of stability and
controllability characteristics using piloted
simulators of TsAGI;
– configurational studies related to
accommodation of passengers and cargo to
verify the possibility of meeting the
airworthiness standards; and
– comparative analysis of fuel and cost
efficiency of flying­wing and conventional
airplanes similar in their purposes.
Obtained Results
The major Project result is generation of
technologies that enable designing of fullscale
FW airplanes with a low technical risk.
The comparison with a conventional
configuration has revealed that the FW design
offered the following advantages:
Take­off weight 13,4% lower
Operating empty weight 6,4% lower
Engine thrust 12% lower
L/D ratio 19% higher
Fuel consumption per flight 24% lower
DOC 7%–9% lower (depending on fuel price)
Fig. 7: Flying Wing model
in TsAGI wind-tunnel
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