Search results
Results from the WOW.Com Content Network
Counter-rotating propellers generally turn clockwise on the left engine and counterclockwise on the right. The advantage of such designs is that counter-rotating propellers balance the effects of torque and P-factor , meaning that such aircraft do not have a critical engine in the case of engine failure.
One of the four contra-rotating propellers on a Tu-95 Russian strategic bomber. In the 1950s, the Soviet Union's Kuznetsov Design Bureau developed the NK-12 turboprop. It drives an eight-blade contra-rotating propeller and, at 15,000 shaft horsepower (11,000 kilowatts), it is the most powerful turboprop in service.
Contra-rotating propellers have benefits when providing thrust in marine applications. Contra-rotating propellers are used on torpedoes due to the natural torque compensation and are also used in some motor boats. The cost of boring out the outer shafts and problems of mounting the inner shaft bearings are not worth pursuing in case of normal ...
Contra-rotating propellers should not be confused with counter-rotating propellers, a term which describes propellers rotating in opposite directions but sitting apart from each other on separate shafts instead of sharing a common axis. Tandem-rotor helicopters such as the CH-47 Chinook also use a counter-rotating arrangement.
On propeller aircraft, there is a difference in the remaining yawing moments after failure of the left or the right (outboard) engine when all propellers rotate in the same direction due to the P-factor. On turbojet and turbofan twin-engine aircraft, there usually is no difference between the yawing moments after failure of a left or right ...
A Wright R-3350 radial engine, showing, R to L, propeller shaft, reduction gearcase, magneto (silver) with wiring, two cylinders (rear with connecting rod), impellor casing (and induction pipe outlets) and injection carburetor (black); separate accessory gearbox at extreme left. Data from Jane's. [9]
The Voith Schneider propeller was originally a design for a hydro-electric turbine. [2] Its Austrian inventor, Ernst Schneider, had a chance meeting on a train with a manager at Voith's subsidiary St. Pölten works; this led to the turbine being investigated by Voith's engineers, who discovered that although it was no more efficient than other water turbines, Schneider's design worked well as ...
In larger and more modern engines, a rubber bushing transmits the torque of the drive shaft to the propeller's hub. Under a damaging load the friction of the bushing in the hub is overcome and the rotating propeller slips on the shaft, preventing overloading of the engine's components. [44] After such an event the rubber bushing may be damaged.