All Questions
Tagged with flight-dynamics helicopter
14
questions
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78
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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
0
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1
answer
101
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What are the effects of whiteout (snow) and brownout (sand/dust) on helos?
Is there any other effect besides low visibility?
Both seem to show very similar conditions.
1
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2
answers
183
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What differences would a helicopter designed to withstand many negative Gs have compared with a normal one?
There are a few helicopters that are able to take negative G's, and to this day only one can actually perform aerobatics (ie. Chuck Aaron's BO-105). The BO 105 is a rigid rotor helicopter that has ...
1
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3
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195
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Can the use of wide-chord supercritical airfoil blades in a helicopter with coaxial counter-rotating rotors solve retreating blade stall?
The problem with retreating blade stall is that it limits the VNE and the overall top speed of helicopters. Retreating blade stall is basically the tip of the retreating blade having too much AoA at a ...
1
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1
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65
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Moment required for disk tilt Cierva Autogyro?
The first prototypes of the Cierva autogyro used a disk tilt mechanism rahter than cyclic pitch by means of a swashplate to achieve roll and pitch (DOI: 10.13140/RG.2.2.19168.94729).
Let's first ...
- 301
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2
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596
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Would an S-92 / CH-148 (or any helicopter) be able to land successfully after rolling over and eating someone with its main rotor in flight?
In the SCP Foundation story "Over/",1 the protagonist and his fiancée get kidnapped by some terrorists looking for information, who eventually throw the two of them out of a CH-148 (with ...
- 28.4k
4
votes
2
answers
229
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What is the direction of the centrifugal force of a hinged helicopter blade?
In helicopter dynamics the flapping angle and corresponding equation is a well known concept. Suppose now that an hinge is added to the rotor, as with gyrocopters and that there is an aerodynamic ...
- 301
1
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1
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Helicopter Basics: How does lead-lag of blades actually help in compensating for increase/decrease in speed due to flapping?
I understand the following -
Due to dissymmetry of lift, flapping up and down occurs.
Since angular momentum has to be conserved, the speed of blade increases/decreases during flapping
up/down ...
- 268
3
votes
1
answer
413
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How are pitching and rolling moments transferred from rotor to the body?
When a rotorcraft pilot moves pushes on the cyclic control stick, the swashplate tilts so that angle of attack of the retreating blades increase and of the advancing blades decrease, which creates ...
- 56.4k
0
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1
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586
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Are there any helicopters with tail rotors where slip-skid ball may be centered even when fuselage is streamlined to the airflow in cruising flight?
In a related answer, I stated
"The tail rotor of a helicopter also generates an aerodynamic
sideforce. Again, just as with the twin-engine airplane with one
failed engine, when the fuselage is ...
- 22.9k
18
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4
answers
6k
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How do "tip jet" helicopters cancel the torque effect of the main rotor?
Some helicopters use "tip jet" on the rotor blades tips such as the McDonnell XH-20 Little Henry and Hiller YH-32 Hornet.
How do they cancel the rotor torque (often canceled by the tail rotor)?
- 959
5
votes
1
answer
492
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Is a retreating blade stall a problem that can be overcome on dual-rotor helicopters?
I know that regular main+tail rotor helicopters stall at higher speeds as the relative airspeed of the retreating blade approaches zero.
I'm curious if coaxial or intermeshing dual-rotor helicopters ...
- 153
1
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3
answers
1k
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How Helicopters Change Attitude (Gyroscopic Precession or Thrust Vector Tilt)
I am trying to determine how helicopters pitch and roll (i.e. change attitude). I have heard two explanations.
1) Pitch/roll change is achieved by tilting the tip path plane and therefor tilting the ...
- 201
11
votes
1
answer
2k
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How do uncoordinated turns (skid, slip) affect a helicopter's turn radius?
Is a helicopter's flight path (track made good) an arc of constant radius regardless if it's a coordinated or uncoordinated turn? (Assume nil wind conditions and that the pilot maintains the angle of ...
- 423