A spinner is an aircraft component, a streamlined fairing fitted over a propeller hub or at the centre of a turbofan engine. Spinners both make the aircraft overall more streamlined, thereby reducing aerodynamic drag, and also smooth the airflow so that it enters the air intakes more efficiently. Spinners also fulfill an aesthetic role on some aircraft designs. [1] [2] [3]
Piston-powered aircraft often have spinners of one of two basic designs. The large spinner fits over the propeller, while the smaller skull cap style is directly attached to the propeller and just covers the propeller mounting bolts. [3]
The spinner may be constructed from aluminium or fibreglass. Often softer grades of aluminium are used to reduce the tendency to crack in service. Early fibreglass spinners introduced as kits for the homebuilt aircraft market in the early 1990s initially developed a poor reputation for cracking. More recent models have resolved these problems and they now function as well as aluminium ones do. [2] [3]
The normal method of installation of a large spinner on a light aircraft involves installing a circular spinner back plate over the engine driveshaft, then the propeller, followed by a spinner front plate. The spinner dome is then mounted over this assembly and secured with screws to the back and front plates. Small plates are usually fitted behind the propeller to fill in the spinner dome cutouts and are secured to the backplate again with screws. Some spinner designs do not incorporate the front plate, although these are not suitable for higher-powered engines. [2] [3]
The loss of a spinner in flight has caused damage to aircraft as well as accidents. If the spinner becomes partially detached then damage to the engine cowling can result, along with a high degree of vibration that results in the need for an immediate engine shut-down and a forced landing. In cases where the spinner has completely departed the aircraft it often impacts the airframe or the windshield, with potentially catastrophic results. [2]
Because of their role as a rotating component and the risk of cracking and failure due to engine vibration, spinners require regular inspection, particularly of the back plate as well as the spinner dome itself. [2]
The first spinners were fitted to aircraft in the early 1910s, originally to reduce drag caused by the large-diameter rotary engines of that era, and also were prominent on World War I-era aircraft, like the Morane-Saulnier N French monoplane fighter, and for the Central Powers, Robert Thelen's Albatros D.I through D.V series of fighter designs. In some cases spinners were found to block airflow to the engine, causing overheating, [4] a problem later solved by careful aerodynamic design. [5]
An aircraft is a vehicle that is able to fly by gaining support from the air. It counters the force of gravity by using either static lift or the dynamic lift of an airfoil, or, in a few cases, direct downward thrust from its engines. Common examples of aircraft include airplanes, helicopters, airships, gliders, paramotors, and hot air balloons.
A fixed-wing aircraft is a heavier-than-air aircraft, such as an airplane, which is capable of flight using aerodynamic lift. Fixed-wing aircraft are distinct from rotary-wing aircraft, and ornithopters. The wings of a fixed-wing aircraft are not necessarily rigid; kites, hang gliders, variable-sweep wing aircraft, and airplanes that use wing morphing are all classified as fixed wing.
The BMW 801 was a powerful German 41.8-litre (2,550 cu in) air-cooled 14-cylinder-radial aircraft engine built by BMW and used in a number of German Luftwaffe aircraft of World War II. Production versions of the twin-row engine generated between 1,560 and 2,000 PS. It was the most produced radial engine of Germany in World War II with more than 61,000 built.
A T-tail is an empennage configuration in which the tailplane of an aircraft is mounted to the top of the fin. The arrangement looks like the capital letter T, hence the name. The T-tail differs from the standard configuration in which the tailplane is mounted to the fuselage at the base of the fin.
In aeronautics, a spoiler is a device which intentionally reduces the lift component of an airfoil in a controlled way. Most often, spoilers are plates on the top surface of a wing that can be extended upward into the airflow to spoil the streamline flow. By so doing, the spoiler creates a controlled stall over the portion of the wing behind it, greatly reducing the lift of that wing section. Spoilers differ from airbrakes in that airbrakes are designed to increase drag without disrupting the lift distribution across the wing span, while spoilers disrupt the lift distribution as well as increasing drag.
In aeronautical and naval engineering, pusher configuration is the term used to describe a drivetrain of air- or watercraft with propulsion device(s) after the engine(s). This is in contrast to the more conventional tractor configuration, which places them in front.
In aviation, the term tractor configuration refers to a propeller-driven fixed-wing aircraft with its engine mounted with the propeller in front, so that the aircraft is "pulled" through the air. This is the usual configuration; the pusher configuration places the airscrew behind, and "pushes" the aircraft forward. Through common usage, the word "propeller" has come to mean any airscrew, whether it pulls or pushes the aircraft.
In aeronautics, air brakes or speed brakes are a type of flight control surface used on an aircraft to increase the drag on the aircraft. When extended into the airstream, air brakes cause an increase in the drag on the aircraft. When not in use, they conform to the local streamlined profile of the aircraft in order to help minimize drag.
A wing tip is the part of the wing that is most distant from the fuselage of a fixed-wing aircraft.
A supersonic aircraft is an aircraft capable of supersonic flight, that is, flying faster than the speed of sound. Supersonic aircraft were developed in the second half of the twentieth century. Supersonic aircraft have been used for research and military purposes, but only two supersonic aircraft, the Tupolev Tu-144 and the Concorde, ever entered service for civil use as airliners. Fighter jets are the most common example of supersonic aircraft.
In aeronautics, icing is the formation of water ice on an aircraft. Icing has resulted in numerous fatal accidents in aviation history. Ice accretion and accumulation can affect the external surfaces of an aircraft – in which case it is referred to as airframe icing – or the engine, resulting in carburetor icing, air inlet icing or more generically engine icing. These phenomena may possibly but do not necessarily occur together.
In aeronautics, a variable-pitch propeller is a type of propeller (airscrew) with blades that can be rotated around their long axis to change the blade pitch. A controllable-pitch propeller is one where the pitch is controlled manually by the pilot. Alternatively, a constant-speed propeller is one where the pilot sets the desired engine speed (RPM), and the blade pitch is controlled automatically without the pilot's intervention so that the rotational speed remains constant. The device which controls the propeller pitch and thus speed is called a propeller governor or constant speed unit.
In a fixed-wing aircraft, the spar is often the main structural member of the wing, running spanwise at right angles to the fuselage. The spar carries flight loads and the weight of the wings while on the ground. Other structural and forming members such as ribs may be attached to the spar or spars, with stressed skin construction also sharing the loads where it is used. There may be more than one spar in a wing or none at all. Where a single spar carries most of the force, it is known as the main spar.
In aeronautics, an aircraft propeller, also called an airscrew, converts rotary motion from an engine or other power source into a swirling slipstream which pushes the propeller forwards or backwards. It comprises a rotating power-driven hub, to which are attached several radial airfoil-section blades such that the whole assembly rotates about a longitudinal axis. The blade pitch may be fixed, manually variable to a few set positions, or of the automatically variable "constant-speed" type.
In aeronautics, a canard is a wing configuration in which a small forewing or foreplane is placed forward of the main wing of a fixed-wing aircraft or a weapon. The term "canard" may be used to describe the aircraft itself, the wing configuration, or the foreplane. Canard wings are also extensively used in guided missiles and smart bombs.
A subsonic aircraft is an aircraft with a maximum speed less than the speed of sound. The term technically describes an aircraft that flies below its critical Mach number, typically around Mach 0.8. All current civil aircraft, including airliners, helicopters, future passenger drones, personal air vehicles and airships, as well as many military types, are subsonic.
The Dunne D.5 was a British experimental aircraft built in 1910. A tailless swept-wing biplane, it was designed by J. W. Dunne and built by Short Brothers at Leysdown for his company, the Blair Atholl Aeroplane Syndicate Ltd. Like its military predecessors it was driven by twin pusher propellers, but it had a considerably more powerful engine.
The wing configuration or planform of a fixed-wing aircraft is its arrangement of lifting and related surfaces.
A glider or sailplane is a type of glider aircraft used in the leisure activity and sport of gliding. This unpowered aircraft can use naturally occurring currents of rising air in the atmosphere to gain altitude. Sailplanes are aerodynamically streamlined and so can fly a significant distance forward for a small decrease in altitude.
In aeronautics, bracing comprises additional structural members which stiffen the functional airframe to give it rigidity and strength under load. Bracing may be applied both internally and externally, and may take the form of struts, which act in compression or tension as the need arises, and/or wires, which act only in tension.
