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| picture: KNOWN MALTA by Peter Grima |
The first early record of a design similar to the helicopter was that of Da Vinci during the Renaissance period. A original concept of having a structure lift off the ground and hover in mid air with personnel on board. Many had thought the idea absurd and impossible, however in 1904 the first helicopter flew and a better more successful version the German Focke-Wulf Fw 61 flew in 1924. The helicopter is very complex and has much improved over the decades. Modern choppers, as many call them, such as the AH64-A Apache, the AH-1 Cobra, and the MI-24 Hind have been suited with top of the line technology and loaded with weapons for military use. Even though many are shaped different and are of different sizes they all run under the same basis for flight. They each have a rotor atop of the platform that rotates to thrusting the air above it downwards to produce a counteractive push upwards on the chopper. What is it about a helicopter that keeps it stable? Wouldn't common sense tell you that this piece of rotating metal would loose control and send it's occupants to theirs deaths? Do some research and see why the helicopter is able to fly the way it does? What are some interesting facts about them? How can they be useful and name some of the ways they have been used and where. I look forward to your comments
A helicopter can fly because the rotor of a helicopter acts like a propeller with rotating wing blades, generating lift to overcome drag. An interesting fact about helicopters is that they are the most versatile flying machines in existence today, and this versatility gives the pilot complete access to three-dimensional space in a way that no airplane can.
ReplyDeleteChip is very correct. A helicopters rotor acts like the prop on a boat, enabling it to create lift, and to fly. But a part of the helicopter that he neglected to mention was the tail-rotor, which is what makes the main rotor useful at all. Without the tail-rotor, the helicopter wouldn't lift at all, it would just spin in circles. It's this opposition of forces throughout the bird that enables it to fly, and makes it such a complicated machine to operate. It might not be correct to say that the tail-rotor is more important than the main rotor, but it is correct to say that without the tail-rotor, the helicopter would be unflyable.
ReplyDeleteWhat he said about manueverability was correct as well. There's a reason that SAR (Search And Rescue) teams use helicopters. It's bacause they can go almost anywhere, without limit. In the U.S. Army, there's an aviation group called the 160th SOAR (Special Operations Aviation Regiment). They are also called the "Nightstalkers" because they are the best of the best at flying helicopters in the worst situations. During Operation Gothic Serpent in Somalia (see: Black Hawk Down) there were SOAR pilots operating all of the helicopters, and at one point, a pilot landed an AH-6 "Little Bird" attack chopper in an alley that was actually narrower than the blades of the rotors to rescue the crew of another downed chopper. His rotor was actually scraping the walls on both sides of him as he landed. You can't do that in a plane.
Time for some fun facts:
ReplyDeleteThe 1st helicopter, "Gyroplane, No. 1", was built by two Frenchman, Jacques and Louis Breguet, and between August 14 and september 29, 1907, the aircraft lifted a single pilot 2 feet in the air for nearly a minute; however, it was so unstable that it required a man at each corner to hold it steady.
The same year, another Frenchman, Paul Cornu, completed the first untethered helicopter flight, raising himself 1 foot in the air for 20 seconds.
Here in America, George de Bothezat built the quadrotor helicopter "De Bothezat helicopter" for the United States Army Air Service, but the Army cancelled the program in 1924, and the aircraft was scrapped.
In 1942, during WWII, Igor Sikorsky's R-4 was the first ever helicopter to be mass produced, with 100 ordered for use by the Allies for rescues in harsh terrain. In total, 131 R-4s were produced, while Sikorsky had made more than 400 helicopters by the end of WWII.
The Soviet Mil-26 helicopter has the highest lifting capacity of any production aircraft at 123,000 pounds, but the helicopter with the greatest lifting capacity ever made was the Mil-12, which had a similar appearance to the CV-22 Osprey, and had a lifting capacity of 231,000 pounds. It also holds the record for the largest helicopter ever built, with two 114 foot rotors.
The largest and heaviest American helicopter is the Sikorsky CH-53E Super Stallion, also called the MH-53E Sea Dragon. Used by the Marines and the Navy, it has an empty weight of 33,226 lb, and a maximum takeoff weight of 73,500 lb. It has 3 General Electric T64-GE-416/416A turboshaft engines to power it's massive 79 foot, seven-bladed main rotor. With two window-mounted XM218 .50 cal. machine guns and a ramp-mounted GAU-21 .50 cal. machine gun with a rate of fire of 1100 RPM, the Super Stallion is a fearsome beast.
I agree with Chip. Everything I found online supports what he said.
ReplyDeleteWhat about a helicopter that keeps it stable? The helicopter's rotor blades (a type of fan thats used to generate the lift & the drag forward in flight) has a certain shape, like the shape of the wings on an airplane. So as the rotors spin, it causes the air to flow faster over the tops of the blades than it does below the blades, causing it to lift.
ReplyDeleteand the tail rotor creates another force pushing clock-wise to counteract the counterclock-wise motion of the main rotor.
ReplyDeleteGreat Comments everyone. You hit the nail right on the head RoseDesire. I purposely left out that piece of information about the helicopter so that you could find it out for yourself. What would you suppose a helicopter would look like flying without a tail rotor? Look at a ch47. Why do you suppose that this helicopter doesn't require a tail rotor?
ReplyDeleteI just looked it up on Google Images, and then on Wikipedia, and the reason that the Chinook is able to stay in the air without a tail rotor because the two rotors rotate in opposite directions. With these rotors turning in opposite directions, there's no need for a tail rotor. Why have a little rotor on a 90 degree angle to the ground when it suits your purposes just as well to have a large rotor thats actually contributing to lifting the payload? It just makes sense.
ReplyDeleteThanks for the comments this week!
ReplyDelete