New answers tagged

3

Ejection of the tipjet exhaust streams in different directions creates a reactive torque on the rotor. This causes the rotor to spin up until aerodynamic drag exactly opposes the jet reaction. So in a way you can say that tipjet helicopters cancel the rotor torque through aerodynamic drag. But no torque is applied to the rotor through the rotor hub. Its ...


8

Think of 2 scenarios: in one you are holding a rocket shaped projectile that is inert and you throw this projectile using your arm. In the second scenario you hold a real rocket, which is then launched. In the first scenario you throw the projectile, and you have to counter the twisting motion of your arm because your arm is imparting a force. In the ...


32

This is a basic physics question, involving Newton's third law of motion (For every action, there is an equal and opposite reaction.) When a centrally mounted engine applies force to turn the rotor, the equal and opposite reaction creates torque on the fuselage. With a tip jet, the force is applied by the jet shooting its exhaust perpendicular to the blade,...


11

Think of the aircraft engine as one isolated system and the rotor as another isolated system. In its simplest terms, torque is the force required to move mass in a circular motion. Torque is caused by the engine providing power to the rotor shaft which moves the mass of the blades. The torque is the interaction of the stationary engine trying to move the ...


1

Helicopters in general use asymmetric aerofoils because they are not required to fly inverted or produce negative lift. Intermeshing helicopters are no different in this regard. The exception would be aerobatic model helicopters, which use symmetrical aerofoils because they are designed for similar performance either way up.


0

Normally helipads are allocated names depending on what taxiways they are adjacent to. For example, Helipad Alpha would be off or near taxiway Alpha. Helipad Charlie would be off of Taxiway Charlie. Results may differ depending on the airport/heliport layout, but this is how the normal naming system works.


1

Maximum pitch angle would totally depend on the type of helicopter you are flying. Each helicopter has its own set of limitations and pitch angles depending on the blade, rpm, etc. The controls include a mechanical stop, and you would hit that limit sooner or later if you put in an overly aggressive control input on the cyclic, or full collective up or down. ...


2

If you are looking up at a bright thing in the southwestern or western sky before 11 PM in March 2020 and you aren't also able to locate the planet Venus at the same time, then the bright thing is the planet Venus. Venus is very high and bright in southwestern or western sky in the evenings these days. Unless it is very near the horizon, it appears to ...


4

Unfortunately, this is an opinion based question. My opinion is based on the fact that my first few hours of helicopter instruction were harder than my first few hours of fixed wing instruction. Takeoff in a helicopter was fairly easy after hover taxiing to the takeoff pad and hover turning 360° with yaw control to visually clear the area. Landing in a ...


0

Click to view, cropped from https://forums.eagle.ru/showthread.php?t=98895 The biggest feature in that area is the fuel tank, which is roughly 0.65 m$^3$ (165 US gal). With a cabin height of 1.2 m (it's not a standing cabin), the base (assuming square) would be 0.74 x 0.74 m (2'5" x 2'5") of floor area, which does look right.


54

If the temperature and conditions are right, yes. Any aircraft which has a heat engine that burns hydrocarbon fuel, which is pretty much any reciprocating or gas turbine engine used in aviation, will emit carbon dioxide and water vapor as byproducts of combustion. It’s just a byproduct of the chemical reaction to produce heat energy in the engine. And when ...


12

Contrails off the engine exhausts is unlikely. But in the right conditions, ie damp air, you can get contrails off the "wingtip" vortices, ie off the rotor blade tips.


-3

In a word: NO. All existing helicopters have their engine exhausts somewhere beneath the main rotor, and that means that the exhaust gases are hugely diluted and dispersed by the enormous downwash from the main rotor. It simply is not possible for a contrail to form under such dilution and turbulence.


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