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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Why do I often see bunches of medical helicopters hovering in clusters in various locations
As you can see in the screenshot there are hovering clusters of medical helicopters in multiple areas. I feel like I see hovering helicopter clusters every time I open the flightradar24 app. I couldn'...
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Can a helicopter have a fully mechanic "elevator"? [closed]
After a research, I've seen prototypes of planes with elevators. What if it could be used as part of the "Air Ambulance" technology on helicopters? Because helicopters have to land first to pick up ...
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How does flare rate and attitude change with altitude during autorotation in Helicopters?
I am presently undergoing Flying Instructor Course on a Single Engine Helicopter.
I have been wondering about following queries :
How does, if it does, the flare rate and attitude change with ...
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In 1982 Admiral Grace Hopper said "I still haven't found out why helicopter rotors go the way they do". If she were here today, how might one answer?
After about 24:50 in the video NSA Releases Internal 1982 Lecture by Computing Pioneer Rear Admiral Grace Hopper Admiral Hopper says:
...Now when it comes to carousels at airports I can see a good ...
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What happens when a helicopter loses the engine and autorotation is not initiated?
I am thinking of a very basic main and tail rotor configuration helicopter, without any aerodynamic surfaces like vertical or horizontal stabilizer, in a steady state horizontal forward flight at ...
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Does a cyclic in a helicopter essentially control rotor attitude?
So the basics of helicopter control as I understand it, at least, in terms of roll and pitch, are as follows:
A helicopter is caused to move through space by means of tilting the main rotor disc, ...
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What is the airspeed record for a helicopter flying backwards?
How fast can a rotocraft go, relative to the air, if it is flying towards its tail?
Tiltrotor and powered lift aircraft do not count. Helicopters and gyroplanes do. The aircraft must have a readily ...
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Trouble with flight school and the change in flight instructors
How do I easily adjust to the instrucuting processess of a new flight instructor, So I can fininsh flight school early enough, I have had 3 flight instructors in the past 2 months and it has stalled ...
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what is the lower pressure plate in the swashplate assembly? is it the same as the lower stationary swash plate? or is it the drive scissors?
Im looking at the rotor assembly of a BlackHawk. The natops manual states the following, "...The lower pressure plate, in conjunction with the main shaft nut, secures the shaft extension to the ...
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How does the Sikorsky X2 technology rotor control blade pitch?
All of the helicopters by Sikorsky using their X2 technology coaxial rotor system don't seem to have a conventional swashplate and control rod assembly for controlling the pitch of the rotor blades. ...
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What are the design principles that result in thin, long-span, narrow chord main rotor blades?
Regardless of the overall design configuration of a helicopter, it appears that helicopters have main rotor blades that all fall into the class of ultrahigh aspect-ratio wing design: that is, you ...
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Could Swashplate be replaced with small electric motors?
In helicopters, the swashplate is used to control the pitch of the blades. Could a set of electric motors, each placed at the root of each blade, be used to control the pitch instead? Has this method ...
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Formula relating propeller torque to lift
I'm trying to find a formulas that relates lift to torque on the rotor shaft. Torque, angular velocity and power are related by the following relationship: $P=\tau \omega$.
I am especially interested ...
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Does information about private heliports need to be published in the AIP?
I am seeking information on what international regulations specify regarding the publication of aeronautical data for a private heliports.
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How to balance the main rotor of helicopter?
In mi17 class helicopters, the OEM had not given an option of adding weights at main rotor hub or blade tips at unit level. The blade sets are usually static balanced when received by units. Is there ...
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What does a letter "R" means in a helipad?
What does it means when a helipads has a letter "R" and a arrow?
Here are some examples and the link to google maps:
https://www.google.com/maps/search/heliport/@35.4638657,139.6262343,40m/...
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Can you do a IFR flight in a uncontrolled space in a helicopter?
Can you do a IFR flight from point A to point B (both within an uncontrolled airspace) in IMC in a helicopter?
Would there be a minimum altitude?
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What factors govern the placement of a helicopter's tail rotor (left or right)?
An image search for 'helicopter' indicates that there isn't a consensus on whether to place the tail rotor to the left or the right of the tail boom, although I'm believe there may be a bias for left.
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What's the purpose of the holes on the Cabri G2 fenestron blades?
What is the purpose of the holes on the blades of the Cabri G2 fenestron? In my opinion drilling the blades like that weakens their cross section under the action of the centrifugal force. Is it ...
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Am I seeing double? What kind of helicopter is this, and how many blades does it actually have?
This June 9, 2024 CNN news video begins with an inset of video of what looks like an Israeli IDF "event". Looking down from a relatively static point in the air, another helicopter is seen ...
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How do you communicate with atc and how can they communicate with you when you change frequency?
How do you let atc know that you are going to a different frequency and how will you be able to talk to them if they need to talk to you will they go to that frequency that you went to?
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What frequencies can you freely speak on? [duplicate]
Are there any frequencies that you can use to communicate with your family at home when you are flying and for a wokie talkie I am wondering if there are just any frequencies that you can speak freely ...
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Why do some helicopters have the tail rotor mounted higher than the tailboom?
Why do some helicopters have the tail rotor mounted high above the tailboom, whereas others have it at the end of the tail boom?
Above the tailboom:
Wiki Commons
At the end of the tailboom:
Boeing....
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Is it plausible that helicopters are safer than cars?
For some reason there is a lot of talk on helicopter safety online at the moment, and one fact that keeps coming up is "helicopters are safer than cars", supported by this article "Are ...
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Can a wind gust below the rotor affect the lift force in a helicopter?
If a helicopter is hovering and a very strong, narrow and focused wind gust comes from the front and passes few feet below the rotor blade without touching the fuselage or any part of the aircraft for ...
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Can a free-falling aircraft with no horizontal (or minimal horizontal velocity) start up and fly to safety?
Inspired by this Grand Theft Auto gif, an aircraft with its engines initially idling is dropped from a high altitude (such as from the top of a building) with no or minimal horizontal velocity. Can it ...
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Does a helicopter actually have a lower rate of fuel consumption in cruise than in hover? [duplicate]
Recently the thought of autogyro flight as "powered autorotation" came to mind. The rotor acts like a fixed wing, providing lift, while a separate source of thrust provides forward motion.
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What is the effect of flying height on helicopter fuel consumption?
Does the height at which a helicopter is flying affect its fuel consumption? Which factors are influencing its fuel consumption?
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Is there a preferred wind direction for a helicopter in hover?
When hovering, how does a pilot deal with wind direction? As when landing is it preferable to point the nose into the wind? Is this a primary consideration for the pilot considering that he may need ...
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Helicopter attitude during take-off and landing (wheels, not skids)
Helicopters with wheels can take-off and land in a level or nose-up attitude (nose wheel off with main wheels on the ground). For example, the pilot of a VIP helicopter might want to take-off in a ...
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Why do American Helicopters not have ejection seats or some form of ejection system?
In Russia there is the Kamov Ka-50 which is a helicopter with a ejection seat that blows off its rotors before the pilot ejects. I was wondering why here in America we Don't have some form of similar ...
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Do helicopters have to pay landing fee?
Is there a landing fee for helicopters?
I ask because since they usually don't use the runway hence doesn't cause maintenance costs for the airport I would imagine they have at least a different fee ...
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What is the arrangement of flapping, drag, and feathering hinges on a fully-articulated rotor hub?
Every diagram I have seen puts the flapping hinge closest to the rotor hub, but there seems to be variation whether the feathering comes next followed by the drag/lead-lag, or vice versa.
For this CH-...
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What is this helicopter (and probe) in the film "Act of Valor"?
In the film Act of Valor, two helicopters are used to airdrop troops and their boats onto a river. (Clip here.)
Firstly can you identify the aircraft?
Second, what is the extremely long probe on the ...
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What exactly are these two cones on top of this Sikorsky S-61 helicopter?
Haven't notice this thing on the Sikorsky, what is it?
Another picture from another angle:
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Why is the PIC position for helicopters the right seat, rather than the left seat as in airplanes?
So far as I am aware, in a fixed wing aircraft having side-by-side seating and dual controls but only a single set of instruments, those instruments are always positioned in front of the left seat. ...
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What is the downwash speed on a typical helicopter?
On a typical 2 or 4 seat helicopter like a Robinson R22/R44, at full throttle at 20ft ASL, if you put a Wind Speed Meter/Anemometer about 10ft below the blades and halfway along a rotor blade's span, ...
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Are fully electric helicopters suitable for military operations?
I read this question about diesel-electric (DE) helicopters, which sparked the following question:
Are fully electric helicopters suitable for military operations?
They are more silent, and electric ...
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Can a single-bladed rotor with cyclically varying torque emulate a swashplate?
Instead of a swash-plate cyclically varying the pitch of the rotor blade(s), could a similar effect be generated by cyclically varying the thrust of the motor on a fixed-pitch single-blade rotor? The ...
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why does the rotor could head (Nr) "overspeed" if the collective is lowered suddenly, what is the Physics behind it
I know that in helicopters the N2 and Nr are coupled. I would appreciate a physical explanation leading to the cause of how the rotor blades could overspeed if collective (power) is lowered suddenly
I ...
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Have there been attempts to break Jean Boulet's 1972 helicopter records? (highest altitude and longest unpowered descent)
So this is the incredible photo of a man accidentally setting a world record.
In 1972 a French pilot named Jean Boulet set out to break the world record for the highest altitude ever reached in a ...
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How to calculate fuel burn rate in Model BK117 helicopter
I am confused which parameters we are use, I have fuel quantity, fuel flow, fuel weight and speed etc is there so how to using and which parameters using the Endurance time calculate in helicopter
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How to identify a NDB on a garmin 430W or GTN650?
I have a Garmin 430W and a GTN 650 interfaced with a G500H in my aircraft. I can program either to go direct to an NDB. The question comes as to whether or not I can identify the navaid. Reading ...
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Gyroscopic Precession in Coaxial Helicopters
I'm trying to understand gyroscopic Precession in the case of coaxial helicopters. Obviously the effect still exists. But if gyroscopic Precession is a result of counter torque. Shouldn't the effect ...
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My ceiling fan preference is to have 5 blades because it's quieter. Do helicopters ever have 5 rotor blades. Why?
My home ceiling fans have 5 blades to reduce the wopwop sound in a quiet room. It probably also moves air more efficiently at a lower spin rate. Can a helicopter operate properly with 5 blades?
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Can you identify this helicopter seen near Boscombe Down?
Please can you identify this helicopter seen near Boscombe Down (near Amesbury, Wiltshire, England) in January 2024?
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H145 helicopter type rating trainings
There are different variants of H145 helicopter (BK117), there are BK117, BK117 C2, BK117 D2 and BK117 D3 helicopter. So if you finish type rating training for example for BK117 D2, and you want to ...
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Autorotation Trajectory Datasets?
I was looking for works/datasets on autorotation trajectories. Now, I have found works like this: Aponso et al, Dalamagkidis et al, Abbeel et al or Nonami et al (Chapter 6).
However, I have a hard ...
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What is the use of Stub Wings on Helicopters?
Some Helicopters like Russian Mi-24, UH-60 etx have Stub Wings. What is the role of such wings?
Russian Mi-24
UH-60
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Do coaxial rotor helicopters have a size limit? [duplicate]
Why haven't there been heavy helicopters like the CH53 with coaxial rotor configuration? Is there any physical limitation inherent to the concept?
I recall someone at Sikorsky saying that their new X2 ...
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