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Questions tagged [helicopter]

A helicopter is a type of rotorcraft in which lift and thrust are supplied by 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 would usually not be able to take off or land.

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What approvals do I need for a helicopter landing?

I have a horrible conflict; my sons are graduating on the same day at about the same time in different states. One in East Greenbush NY the other in Beverly MA. I am interested in hiring a ...
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Where can I find info or techniques on calculating the influence of a duct on the thrust and efficiency of a propeller?

I am trying to run numbers on a concept VTOL fixed-wing aircraft, and I am looking at having fans or props positioned inside the wings, (which would therefore make the wings relatively thick for a ...
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Do Military Turboshaft engines have a distinctly different sound from Civilian ones?

I live in India, and near an airbase so there are a moderate amount of helicopters flying overhead. My friend claims that he can distinguish between a civilian helicopter or a military one based on ...
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How does a circulation control helicopter work

This essay describes that this helicopter uses circulation control of the rotor for cyclic and collective control, but not how circulation control works. https://ntrs.nasa.gov/archive/nasa/casi.ntrs....
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What are the fatigue regulations in the US and Australia for military transport helicopters/rotorcraft?

For transport category military helicopters, what are the fatigue regulations as specified by the US and Australian regulatory bodies? I've managed to find that FAA has FAR 29.571 (US) but this ...
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What is the total lift equation of a helicopter with 3 Flettner rotors?

I'm doing research regarding the possiblity of using Flettner rotors on helicopters. I would like to derive the total lift equation for a helicopter that consist of 3 Flettner rotors. Given that: ...
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How do active blades work on helicopters?

Can someone throw some light on 'active blades' as used in helicopters? I'm mostly interested in the use of piezoelectric material and actuators. How are the actuators able to sense the change of ...
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How far can one be from an helipad when marshalling an helicopter?

I considered 25 meters (as per UN SOP's) but after working years with MI-8's the downwash can flatten a big man. I'm interested in procedures from the FAA etc. ...
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What is the dimensionally smallest 2-seat helicopter?

Considering only a two place helicopters (2 crew, or 1 crew and 1 passenger).
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Where can I find official information about a recent crash in Mexico?

I have heard about a helicopter crash involving an Agusta A 109 in Mexico, that seems to be causing some turmoil due to the deaths of a newly-elected governor and her husband. Is there any info about ...
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How is the inflow velocity distributed of a tilted and trimmed rotor in hover?

I'm wondering of how the inflow velocities per blade look during one revolution of a real-life helicopter in hover (no inflow velocity into the rotor plane) with a tilted rotor plane about 20 deg. Is ...
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What is the heaviest payload ever carried by a single main rotor helicopter?

What is the most heavy payload ever carried by a single main rotor Helicopter?
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Where can I find more details about how ornithopters work?

I learnt about the special helicopter-ornithopter which was put forward by Delft University. Its principle is different from a common helicopter and it doesn't need a tail rotor. But there is very ...
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What are point in space approaches (as they pertain to helicopters)?

Can someone please help me understand point in space approaches as they pertain to helicopters? When will you use one, and how? Also, how is HAL associated with point in space?
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Will Thrust on Rotor (Main) increase with altitude?

Can some one please let me know,if the thrust required on the rotor head increases with the increase in altitude in an Helicopter or decreases with increase in Altitude?. Thanks in advance, Pawan
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Are there attempts at fly-by-wire servo flap controlled rotor?

Reading this question and then this document about servo flap controlled rotor I was wondering if there has been any attempt at building one fixed hub helicopter with twistable blades hosting at 75% ...
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How is static droop achieved in mechanical governors

The Bendix power turbine governor in the Bell 206 is just simple flyweight arrangement which controls a pneumatic signal to the FCU. How is static droop achieved in this type of system?
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Where to find information on weight breakdown for helicopters?

I would be interested in information on the weight breakdown for the different components of a helicopter. How much of the maximum gross weight is related to the airframe, engine, gearboxes, ...
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How to properly estimate induced flow

Good day. I am currently in a group that is projecting a rotor that when launched must enter in autorotation. The estimated velocity of descent is $V_z=1.29$ $m/s$ which is approximately the same ...
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What is the relationship between speed, torque and pitch in a helicopter?

Can someone clarify the relationship between aircraft speed, torque, prop length and pitch and how this applies to a helicopter. In addition I want to know if the amount of lift a helicopter ...
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Would a helicoper be able to perform a forward inversion (front flip)?

This is inspired by a previous question What would happen if I bank a helicopter then pull hard on the cyclic? I've seen some pretty radical videos of piloting by Chuck Aaron, but I've not seen a ...
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How to calculate optimal prop diameter, pitch, torque and power coefficient given required thrust?

this is my first post here, so bear with me if this isn't the right place. I'm coming here from Stack Overflow, and this seemed to be the most relevant Stack Exchange for my question. So, I'm ...