What is Helicopter: Definition and 205 Discussions

A helicopter is a type of rotorcraft in which lift and thrust are supplied by horizontally-spinning rotors. This allows the helicopter to take off and land vertically, to hover, and to fly forward, backward and laterally. These attributes allow helicopters to be used in congested or isolated areas where fixed-wing aircraft and many forms of VTOL (Vertical TakeOff and Landing) aircraft cannot perform.
In 1942 the Sikorsky R-4 became the first helicopter to reach full-scale production.Although most earlier designs used more than one main rotor, the configuration of a single main rotor (monocopter) accompanied by a vertical anti-torque tail rotor has become the most common helicopter configuration. Twin-main rotor helicopters (bicopters), in either tandem or transverse rotors configurations, are also in use due to their greater payload capacity than the monorotor design. Coaxial-rotor helicopters, tiltrotor aircraft, and compound helicopters are all flying today. Quadrotor helicopters (quadcopters) were pioneered as early as 1907 in France, and other types of multicopters have been developed for specialized applications such as drones.

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  1. M

    Is a Helicopter on a Geostationary Orbit?

    Is a helicopter which is stationary relative to the surface on a geostationary orbit? Why, or why not?
  2. D

    Power required the support a helicopter

    A rescue helicopter of mass 810 kg, supports itself in a stationary position by imparting a downward velocity, v, to the air in a circle of radius 4.0 m. The density of the air is 1.20 kg m-3. Calculate: (i) the value of v (ii) the power, P, required to support the helicopter So, I do...
  3. P

    A fire helicopter carries a bucket of water

    Homework Statement A fire helicopter carries a bucket of water at the end of a cable 20.0 m long. The empty bucket's mass is 580 kg. As the aircraft flies back from a fire at a constant speed of 49.5 m/s, the cable makes an angle of 35.0 deg with respect to the vertical. a) Determine the...
  4. D

    Motion of an object dropped from a descending and ascending helicopter

    [b]1. a) A small mail bag is released from a helicopter that is descending steadily at 3.34 m/s. After 2.95 s, what is the speed of the mailbag? The acceleration of gravity is 9.8 m/s2 . Answer in units of m/s b) After the mailbag is dropped, the helicopter continues descending for 1 s but...
  5. L

    How much power do you need to hover? (human powered helicopter)

    This question, or some form thereof, has come up a lot in this forum. The answer is that if you can have a propeller big enough, you can hover with almost zero power. But you can only build so big before physics and material limitations get in the way... These guys didn't seem to give a hoot...
  6. F

    Helicopter air projection velocity problem

    So, I got a challenge question from my physics teacher but despite attacking it from different angles I’m not quite sure I’ve gotten the correct solution, in fact most of it was just shady assumptions which I’m not sure were supposed to be made, so I’d like to ask whether this is anywhere near...
  7. M

    Helicopter construction tips wanted

    So my friend and I are building a helicopter this summer. I was designing the propeller blades and could not figure out what angle a stood for in the pitch equation a=arctan(P/2pi*r) P=tan(a)2pi*r) Also if anyone has any tips or has done this, any advice would be extremely helpful! Thanks!
  8. A

    Engineering Is a Chinook-Style Design the Key to a Successful Rubber Motored Helicopter?

    Homework Statement For a Science Olympiad project I need to make a rubber motored helicopter, and with this I need to find the best design for one. One special rule in this is that Chinook styled helicopters get 3x their original flight time, I was wondering if that would be just to encourage...
  9. C

    Helicopter, travelling horizontally, is 82 m above the ground. The pil

    Homework Statement helicopter, traveling horizontally, is 82 m above the ground. The pilot prepares to release a relief package intended to land on the ground 96 m horizontally ahead. Air resistance is negligible. The pilot does not throw the package, but let's it drop. What is the...
  10. H

    Conservation of momentum - falling from hovering helicopter

    Homework Statement Bronco dives from a hovering helicopter and finds his momentum increasing. Does this violate the conservation of momentum? Homework Equations p(before) = p(after) The Attempt at a Solution no, this does not violate the c.o.m, because it is a closed system of...
  11. W

    What happens to the helicopter when

    What happens to the helicopter when... Hello all, I recently came up with an interesting situation in which I cannot predict the outcome. This is purely an item of interest, not an experiment I intend to try. After flying my ultra-micro rc helicopter today, I thought of a strange scenario...
  12. I

    HELP ME - Lift equation for Helicopter Fan

    NOOB ALERT - I'm not trying to design a helicopter or a spaceship or something ridiculous, I just want to design a little hovercraft with a computer fan, so don't get all indignant and righteous at me. Anyhoo, I found this Lift equation and tried experimenting with some numbers, just to get a...
  13. G

    Helicopter UAV - Required Power

    Hey guys, I'm currently doing conceptual performance analysis of a UAV helicopter in hover. I'm having some conflicting results however, and if anyone could help me out, that would be great. Here are some of the basic design constants I'm working with: GTOW: 95kg κ = 1.15 (induced power...
  14. O

    Helicopter Flight and Jet Pack Adventure

    A helicopter carrying Dr. Evil takes off with a constant upward acceleration of 6.0m/s^2 . Secret agent Austin Powers jumps on just as the helicopter lifts off the ground. After the two men struggle for 12.0s , Powers shuts off the engine and steps out of the helicopter. Assume that the...
  15. B

    Webassign - Dropping a Package From a Helicopter

    Q: A helicopter is ascending vertically with a speed of 2.00 m/s. At a height of 160 m above the Earth, a package is dropped from a window. How much time does it take for the package to reach the ground? Attempt: [how long it takes to reach the height] v=delta d/time 2=160/time...
  16. N

    Will the Helicopter Appear in the Same Position After One Day?

    Suppose a helicopter is stationary at certain height And a observer sees it from ground. But after one day the observer again sees the stationary helicopter than will it appear To be at the same Position Or somewhere else
  17. A

    Acceleration of the helicopter as it starts to rise

    Homework Statement At take off, the rotor blades of a helicopter propel 2400 kg of air vertically downwards each second. The air, intially at rest, is given a speed of 11ms^-1 QN: the mass of the helicopter is 2500 kg. Find the acceleration of the helicopter as it starts to rise...
  18. 0

    Simple Question to do with TORQUE on a helicopter

    Homework Statement If the force pushing the helicopter blades from the pivot point surely r is 0... therefore T (torque) is 0 also... Homework Equations r is the Length from pivot point to force F is force τ= r × F ×sin(θ) The Attempt at a Solution
  19. J

    1-Dimensional Motion Helicopter Problem (PPB)

    Homework Statement From People's Physics Book, ch. 3: Homework Equations For a. I got 23 m/s which is correct and b, 3.6 s which is correct as well. For c I chose the equation x(t)=x0+v0t+1/2at^2 The Attempt at a Solution And plugged things in like so... (where upwards is...
  20. N

    Solving for Velocity & Distance of Mailbag: Helicopter Moving at 2.98 m/s

    A small mailbag is released from a helicopter that is descending steadily at 2.98 m/s. (a) After 5.00 s, what is the speed of the mailbag? (b) How far is it below the helicopter? (c) What are your answers to parts (a) and (b) if the helicopter is rising steadily at 2.98 m/s? I tried...
  21. J

    MHB How did you achieve a score of nearly 2000 in the helicopter game?

    I swear I will get the high score if it's the last thing I do...
  22. U

    1-D Kinematics Problem/Free Fall. A helicopter carrying Dr. Evil

    1-D Kinematics Problem/Free Fall. "A helicopter carrying Dr. Evil..." NOTE: I'm new here and I wanted to make sure I am not breaking the rules: I show most of my work step by step for this problem since there are so many things going on in it. My question is whether or not my though process is...
  23. M

    The position of a 2.75x10^5 N training helicopter under test is given by

    Homework Statement The position of a 2.75x10^5 N training helicopter under test is given by...? vector r = (0.020m/s^3)t^3ihat+(2.2 m/s)tjhat-(0.060m/s^2)t^2 khat Find the net force on the helicopter at t=5.0s Express your answer in terms of ihat, jhat , and khat . Express your...
  24. N

    Im trying to work out the acceleration and ave velocity for a model helicopter

    Homework Statement The chopper is 700g and is being pushed with a 10N force(thrust), it flies for 10 secs Homework Equations I need to work out the ave acceleration, velocity and distance traveled after 10 secs The Attempt at a Solution im sure I am doing something wrong, i know...
  25. X

    Physics Forces Problem: Helicopter lifting a truck

    Homework Statement A large (15,000-kg) military helicopter lifts a 6000-kg truck straight up out of a danger zone with an acceleration of 4 m/s2. Calculate the tension in the lifting cable. Homework Equations F = ma W = mg The Attempt at a Solution I believe T = 8.3 * 104N...
  26. J

    Solving Problem 14.18: An Airplane and Helicopter Collision

    Homework Statement The problem I must complete is problem 14.18 14.17 A small airplane of mass 1500 kg and a helicopter of mass 3000 kg flying at an altitude of 1200 m are observed to collide directly above a tower located at O in a wooded area. Four minutes earlier the helicopter had been...
  27. B

    Engine Power required to lift the Helicopter?

    I want to design a RC helicopter powered by a gas engine. The total mass to be lifted by the helicopter is 25 to 30 Kg. What is the engine power or engine size (in cc) required to lift the helicopter? Can someone please provide me some calculation? Regards
  28. K

    What is the total lift for a fixed wing plane and helicopter?

    I came to know that Fixed wing as well as propeller lift equations are same [Am I right]? Anyways I have question. What's total lift for fixed wing plane with Wing length of 4 m, 1 m width, Angle of attack = 16 degree, and Wind/plane speed of 6 m/s? Secondly, what's total lift for...
  29. M

    Helicopter rotor acceleration

    How would you calculate the acceleration of the following two points? http://img341.imageshack.us/img341/917/helicoptor.jpg Uploaded with ImageShack.us1) The tip of the helicopter blade The diameter of the hub = d The length of the rotor = l The flapping angle: theta = A sin(omega*t)...
  30. B

    The Principle of the Helicopter

    The first heavier-than-air flying machines had wings whose airfoil effect provided the force of lift, due to their curvature (convex in the downward direction) which allowed air to flow more slowly along the lower surface of the wing than along the upper surface of the wing, whose curvature...
  31. jaketodd

    Helicopter - Variable Air Density

    This is not homework. If you descend toward the ground in a helicopter, the density of the air is going to increase. I'm curious: Is the amount of energy required to turn the blades directly proportional to the density of the air? For instance: If the air density doubles, does the energy...
  32. F

    How Does a Helicopter Tension Problem Affect Load Dynamics?

    http://img692.imageshack.us/img692/7692/elevatorproblem.png Uploaded with ImageShack.us Is this correct? *** Should say therefore not thereforce. Thanks.
  33. Z

    Roational Mechanics of Helicopter Blades

    Homework Statement A uniform helicopter rotor blade is 8.82 m long, has a mass of 108 kg, and is attached to the rotor axle by a single bolt. (a) What is the magnitude of the force on the bolt from the axle when the rotor is turning at 302 rev/min? (Hint: For this calculation the blade can...
  34. J

    What is the Best Formula for Calculating Thrust in Helicopter Design?

    Hey, i am designing a helicopter having a bit different design. (If you have any design then suggest me but remember, i have to built it by my own.) and you i have to make it cheap and small just like a toy. I am a beginner so guide me if i am wrong and suggestion are most welcomed. Now i...
  35. R

    How if the small RC helicopter Hover but the train is moving?

    How if the small RC helicopter Hover at inside center of the train . the train is moving constant velocity. will the helicopter moving backward?
  36. H

    Calculating helicopter lift

    Homework Statement I've been trying to find a simple equation for calculating the lift (or thrust) of a RC helicopter and I've found a few that are different. Homework Equations 1) Lift = circular area swept by rotor blades \times density of air \times velocity of air exiting disk \times...
  37. H

    Converting Rotor Frequency to Helicopter Thrust: Finding the Missing Equation

    Homework Statement I am doing an EEI relating to how the ground effect influences an RC helicopter's thrust. Homework Equations Are there any equations for converting the frequency of a helicopter's rotor blades to the power used? or alternatively is there another way to calculate the...
  38. D

    Electric Power Line Cleaning Helicopter

    We are in the midst of a drought here in Houston and the other day a utility helicopter flew by our office building. The helicopter had a rod located on the helicopter's nose or close to the nose which sticks out about 10 feet or so, and the crew were leaning out the door and spraying down the...
  39. M

    Helicopter in a Magnetic Field - Verticle Component

    Homework Statement A Helicopter with blades that span 10.7m across is operating in an area where the Earth's magnetic field is 5.85 x 10-5T at an angle of 66o to the horizontal. Prior to takeoff the rotor blades are moving at 375rpm in a clockwise direction when viewed from the ground...
  40. A

    Helicopter tail returned from Pakistan

    Just a question. What happened to the rest of the helicopter? I was trying to find out more about the other half, and seem to be getting nowhere. Any link or quick answer would be welcome. thanks edit ... never mind.. asking the wrong question never works...
  41. T

    Seal Team Six Helicopter Crash 5/1

    As I guess everyone knows, during the Bin Laden raid the Seal's stealth helicopter crashed. Several things were offered as possible reasons: the stealth modifications altered the flight characteristics in unpredictable ways, it was more humid or hot than they expected, and that the high walls...
  42. A

    First (?) human powered helicopter flight

    Small accomplishment but hopefully it'll lead to greater things, here's the video: http://ca.news.yahoo.com/video/tech-22186835/calif-students-build-musical-robots-then-jam-25217074.html
  43. ThomasMagnus

    Helicopter carrying a water balloon

    Homework Statement A helicopter accelerates horizontally while carrying a 220kg water balloon by a rope. a)Draw a free-body diagram of the water balloon. (ignore air resistance.) b) Find the magnitude and direction of the helicopter's acceleration.The Attempt at a Solution a) b) To find...
  44. H

    Velocity Calculation for helicopter rotor question

    Hello, I'm creating an excel file to calculate the velocity of one rotor of a helicopter, and I'm getting really weird answer, in comparison to the one a friend of my who does aerospace engineering give me. I don't do an aerospace engineering course but this is a project I've been researching...
  45. S

    Ball dropped from a helicopter

    Homework Statement A ball is dropped from a helicopter that is descending steadily at 1.52 m/s. (a) After 3.00s, what is the speed of the ball? (b) How far is it below the helicopter? Homework Equations unsure The Attempt at a Solution don't know where to start
  46. M

    Tilting a helicopter rotor, does it create torque?

    Hello I am making a helicopter flight simulation and I need an answer to this question: when you push the cyclic forward, does this create a torque which will rotate the helicopter. if the answer is yes, please tell me what counteracts this torque and stops the rotation when I return the...
  47. A

    Helicopter Thrust Calculation | Fuel Mass Included

    can anyone help me out to calculate the thrust when helicopter takes off with mass of fuel?
  48. F

    Helicopter Rotor Lift Equation

    Hello! I am creating, or at least attempting to create, a human-powered helicopter. I need an equation to figure out the lift from the rotors. I plan to use four counter-rotating rotors, three blades each, and each blade made of foam, with aluminum ribbing. The blades will be six feet each...
  49. magi

    Revolutionary Silent Santa Helicopter Concept

    Hello. A helicopter make a lot of noise and turbulence. Why not separate engine and rotor from the cockpit. When the engine and rotor start/land it need less power because of the less weight. Then when it is high enough it lower wires and connect to the cockpit and lift the pilot and...
  50. JJBladester

    Mass center of system (airplane and helicopter crash)

    Homework Statement A small airplane of mass 1500 kg and a helicopter of mass 3000 kg flying at an altitude of 1200 m are observed to collide directly above a tower located at O in a wooded area. Four minutes earlier the helicopter had been sighted 8.4km due west of the tower and the...
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