ON TAKEOFF – THE PILOT

Attract the attention of athletes and spectators time the model is tailless. Most of them presented in the traditional competition “Experiment” in recent years, has a wing to direct the sweep and power system tractor or pusher propeller. However, this scheme has a number of inherent disadvantages. So, with the engine in front of the wing there is a need for additional balancing weight for balancing the tail model, the tail boom has to greatly increase to ensure a sufficient efficiency of the vertical stabilizer. And when using a power plant with pusher propeller there is a significant probability of hitting the hands of the athlete during the spinning propeller when starting Tierney.

From these drawbacks could be eliminated by the scheme with forward-swept wing. It also allows you to get the model high flight performance. Thus, we propose timername “wing” consistently had three relatives on the geometry options, and they all helped the designer every time to become the winner of the competition “Experiment”. Studies have shown — to ensure that longitudinal balance of the machine with forward-swept wings rather small uniform positive twist and 4.5° (the profile of the wing is concave with a bent up tail, modified from the profile of Kupffer). The increase in the twist gives rise to losses for balancing model, which ultimately reduces its aerodynamic quality. The use of split two-piece wing with different angles of zaklinanie sections requires a lot of stability (i.e., greater aerodynamic twist), since the breakdown of the flow occurs in all sections simultaneously unlike the wing with a uniform twist. In the latter case, the failure gradually extends in size and the model manages to exit at small angles of attack before stalling at the corkscrew.

Time is flying in two modes — motor climb (active phase) and the cladding. Each of these stages dictates the terms of the balancing adjustment models should be separate for each flight mode. Tierney tailless scheme has its own characteristic features. The complexity of regulation and the lack of information about the aerodynamics of a particular device lead to ensure the smooth running of the spacecraft in the initial stage of overflights is extremely difficult. Therefore, the nodes in the model should have a high strength under impact design elements are required to rusticbeauty without damage of details of their attachment. And the wing hinge must have greater rigidity, since the bending of a swept wing there is an additional twist, sensitively affecting the longitudinal balance.

 

 

 

 

 

Based on these requirements, the proposed timemay designed dvuhkonusnyj, with braces and a sewn toe. The lack of sharp corners and breaks in the power scheme of the longitudinal framing allows for greater strength and rigidity. The lining of forehead profile — balsa or shell is laminated of fiberglass or other synthetic fibrous material in two layers. The trailing edge is made of two layers of fiberglass glued between nipples stringer or pine slats with glued on her “knife.” made of aluminum of 0.3 mm thickness.

Each console is hinged on the fuselage by means of two bayonet plates. They were collected from three sheets of titanium or stainless steel with a thickness of 0.5 mm each, and fastened between the flanges of the spars with plywood linings. Console are fixed against slipping two rubber rings. Power frames of the fuselage, in the cavity which includes a bayonet plate, represent a plywood sheet duralumin (0,5 — 1,5 — 1,0 — 1,5 — 0,5 mm{. This design sample is good enough to perceive bending moments from the wing, while providing easy release of the strips from the fuselage upon impact model.