If you mean rotor blades, theoretically, only one (provided it is counterbalanced and moves fast enough). But you'll typically see two or more. Helicopters use more than one because it requires less rotor speed to get the same lift, and it also runs a lower risk of failure in the mechanical systems. Many rotocraft use four or five, and some up to six or seven blades. There are a few helicopters that use two main rotors, and they are counter rotating so that their torque cancels and a tail rotor is not necessary. But the mechanical complexity of these main rotor systems impinges on mechanical reliability.
The number of blades is one aspect of how much weight a helicopter can carry. From the single rotor bladed Boelkow BO-102 that could only hover to the massive Mil Mi-12 with 10 blades and 4 engines that could lift 213,400lbs almost every design type has been attempted.
The size of the helicopter, it's intended use, and how much weight it is ment to carry are all determining factors in how many blades are used.
In jets, speed boats, rockets, some helicopters
Some inventions that were created based on his principle was airplanes, helicopters, and hotair ballons.
diamonds are used for there strength and there ablity to remain sharp
That is to warn birds so that large flock of birds do not fly into the power lines. Also helicopters.
Fans can have any number blades--even one! (but then you need a counterweight for balance). There are airplanes that have one blade for a propeller. There are many variables that figure into how many blades a fan has. Air velocity, noise, shape of the blade, length of the blade, material cost, vibration, etc. For airplanes sometimes they change 2-bladed propellers for three or four or more to get different flying characteristics.
Different helicopters have different landing gear. some just have skids, some have 3 wheels, some have 4.
The number of blades required is proportional to the amount of lift required. There are several factors that affect the amount of lift produced by rotor blades. They are the shape of the air foil, the rotational speed, the angle of attack, the length of the rotor blades, and the strength of the blades. All of these have practical limits. Adding an additional blade helps keep all these parameters within practical limits.
Huey, Wessex, Sea King, Merlin, Blackhawk are some of the best.
The alliteration for helicopters could be higher helicopters or heavy helicopters
there are some planes designed so that the wings are made of propellor blades so that it rises straight up of the ground, but the differemce is that its still called a plane, not a helicopter
You need some typeface to display text and numbers. You can choose different ones for different headings or numbers, whatever you choose.You need some typeface to display text and numbers. You can choose different ones for different headings or numbers, whatever you choose.You need some typeface to display text and numbers. You can choose different ones for different headings or numbers, whatever you choose.You need some typeface to display text and numbers. You can choose different ones for different headings or numbers, whatever you choose.You need some typeface to display text and numbers. You can choose different ones for different headings or numbers, whatever you choose.You need some typeface to display text and numbers. You can choose different ones for different headings or numbers, whatever you choose.You need some typeface to display text and numbers. You can choose different ones for different headings or numbers, whatever you choose.You need some typeface to display text and numbers. You can choose different ones for different headings or numbers, whatever you choose.You need some typeface to display text and numbers. You can choose different ones for different headings or numbers, whatever you choose.You need some typeface to display text and numbers. You can choose different ones for different headings or numbers, whatever you choose.You need some typeface to display text and numbers. You can choose different ones for different headings or numbers, whatever you choose.
hi every1 I'm not sure what the name is but helicopters are made out of heavy metal, helicopters are engine powered due to them being made out of metal, helicopters could not be wind powered because of the wind not being able to lift the helicopter off the ground. sorry y about any spelling mistakes I'm only 11 so... Answer Most helicopters in the past were made of aluminun, just like airplanes. The first ones had some wood construction, including wooden blades. The engine and controls are made of high-strength, forged parts. Some are steel and some are titanium (Ti6Al4V and other newer alloys). Modern helicopters are made of composite structure, such as E-glass and other fiber composite materials. The helicopter blades and the yoke are also made of woven composite materials that are baked in an oven. The landing gears are made from high-strength steel parts.
On most helicopters, the main rotor turns in a clockwise motion. If you were sitting in the cockpit looking out the front, the rotor blades would swing from the left side 'round the front to the right side. French made helicopters are the exception, they rotate the opposite direction, which can cause some confusion for the pilot if they are not prepared.
Yes, some opt to use helicopters for crop dusting.
Some large helicopters use 'drogue and hose' refuelling
Helicopters can land where airplanes cannot.
Not really. There are helicopters the reduce noice significantly but all helicopters make some noise. largely due to their engines. This is esspecially the case if they are powered by turbine engines. The blades that cut through the air also make some noise There was a helicopter that was built during Vietnam that made very little noise due to extensive modifications. It was called the OH-6 "Loach." It was used for special ops missions see this link http://www.airspacemag.com/military-aviation/16047922.HTML