121
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Can this helicopter/wrecking ball combo remain airborne?
EDIT
Huge apologies to one and all, in my first version of this answer I mistyped 184 as 84, and then proceeded to do all my calculations based on that. This is the corrected version.
Also, huge ...
- 946
76
votes
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Should the helicopter be washed after any sea mission?
The helicopter shown is an Anti-Submarine Warfare Helicopter. ASW helicopters generally have the ability to detect submarines either Passively or Actively. Passively, sonar-buoys are dropped into the ...
- 1,166
74
votes
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Do helicopters use more fuel when hovering?
Yes it is correct that helicopters use more fuel when hovering: the engine needs to apply more power to overcome drag. Here is a graph of the engine power required for different airspeeds, from J. ...
- 57.9k
73
votes
Why do police helicopters always fly in circles?
Police helicopters don't always fly in circles. I've often seen my local police helicopter hovering. There are a few reasons you might have seen police helicopters flying in circles:-
Not all types ...
- 12.5k
69
votes
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Why do helicopters have windows near the pedals?
These fall into a category known as vertical reference windows. They can be used for many purposes, but essentially, they allow us to gain a better spatial picture of the orientation of our aircraft, ...
- 4,749
62
votes
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What helicopter has the most rotor blades?
Special mention for Raúl Pateras Pescara de Castelluccio (good article) who was fond of lots and lots of rotor blades, settling on sixteen for most of his designs, although his Model 3 had twenty.
...
- 9,441
58
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Why would a helicopter climb in a spiral?
A helicopter will achieve its best climb rate at a moderate forward speed. Climbing in a spiral helps to have forward speed in what is essentially a vertical climb.
In a hover all the airflow which ...
- 218k
57
votes
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How can a helicopter be designed without a tail rotor?
The torque in a helicopter is generated by the engine driving the main rotor in one direction, which causes the fuselage to spin in the other direction. The tail rotor shaft is horizontally mounted ...
- 2,058
57
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Can helicopters create contrails?
If the temperature and conditions are right, yes.
Any aircraft which has a heat engine that burns hydrocarbon fuel, which is pretty much any reciprocating or gas turbine engine used in aviation, will ...
- 65.5k
56
votes
Why can't helicopters or Zeppelins drop fire-fighting material on burning buildings?
First, they have been used, like in case of the Federation tower fire in Moscow on 2012. The image below shows a Kamov Ka-32A11BC being used to fight fire in that case.
Helicopter fighting Federation ...
- 98.6k
56
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Is a helicopter ride unsafe for young children?
A few notes of update.
Evidence from other operators that there is no hard age limit
There is no upper or lower age limit for pleasure flight however we recommend that children under 12 are ...
- 25.7k
55
votes
Can all helicopters hover, and how long does it take to "stop"?
As noted in another answer, all helicopters can hover, but a so-called "high hover" (out of ground effect or especially at operational altitude) is a more difficult maneuver, requiring more power than ...
- 14.4k
53
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Do the Mt. Everest rescue helicopters have modified engines to operate at high altitudes?
No, the helicopters are standard production versions. The Eurocopter AS350 is a common model used for these operations.
In 2005, Didier Delsalle landed a Eurocopter AS350 B3 on the summit of Mt. ...
- 69.7k
51
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Can this helicopter/wrecking ball combo remain airborne?
The helicopter would be a UH60 Blackhawk. Max payload on a hook is 9000lb. At your mild steel density this is half a cubic meter, so the picture as you describe is impossible.
- 16.6k
50
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Why do helicopters have such limited range?
Helicopters are very inefficient in forward flight, for several reasons.
Consider Glauert's high speed assumption, i.e. the helicopter can be represented as an aircraft with a circular wing during ...
- 704
50
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What would the reason be for this helicopter maneuver?
Ex-Royal Air Force helicopter force here, spent a lot of time around Chinooks.
I think the main answer is "because I can", but I can think of a legitimate combat use.
You are heavy, and forced to ...
- 30.8k
50
votes
Can a helicopter carry a large airplane?
If you look more closely, this "airplane" is only the husk of a Tupolev Tu-134, a rather small airliner, and the helicopter is a Mil-26, the heaviest helicopter ever to go into production. Not only ...
- 218k
48
votes
Can this helicopter/wrecking ball combo remain airborne?
Of course the photo is absolutely real. I know a guy who knows a guy who says he met the guy in front!
3) Assume the wrecking ball is solid mild steel with a density of 7.85 g/cm3.
That's where ...
- 17.7k
46
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Flying in a helicopter with open doors: why don't people fall out?
Aircraft, fixed-wing or rotorcraft, have limited capability to produce a sideways force, so they simply can't throw you out.
It is a matter of physics. Inertial forces (gravity and centrifugal force) ...
- 54.1k
46
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Why is the UH-60 tail rotor canted?
John K and Koyovis's answers are both correct. However, as a former pilot of the UH-60 and a mechanical engineer here is a simpler version.
A helicopter must be balanced. If the front is much ...
- 476
46
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How do helicopters avoid detection from enemies by using IR suppressors?
An IR sensor detects objects that are at a higher (or lower but that's not how missiles work) temperature than the surrounding environment, most of the helicopter won't be that much hotter or cooler ...
- 49.6k
45
votes
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What happens when all electrical systems in a helicopter fail?
The reason for the failure is important actually. If all the electrical systems on an EC135 helicopter fail in your classic EMP scenario then the helicopter has to make an emergency landing as the jet ...
- 49.6k
43
votes
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What is the loud noise of a helicopter when the rotors are not yet moving?
The sound you're hearing is the APU (Auxiliary Power Unit) running.
Turbine (jet) engines turn at a much higher RPM than reciprocating engines. This means that an electric starter motor would have to ...
- 9,077
43
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Why do helicopters have skids?
Image source
Larger helicopters have landing wheels, and as we can see on the picture above, they are placed as far outward as practically possible in order to provide stability in the landing. Touch ...
- 57.9k
42
votes
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Why aren't there more passenger helicopters?
Airplanes are much more efficient, much faster and scale better.
Helicopters are limited to around 150 knots because when flying forward the tip of the advancing blade must not exceed the speed of ...
- 54.1k
41
votes
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Why don't helicopters always takeoff from a hover out of ground-effect?
Forward flight is much more efficient than hovering. As airspeed builds, lift increases from "translational" lift as the air moves more horizontally over the disc. Since the relative airflow is more ...
- 30.8k
41
votes
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Why don't we have helicopter airlines?
They do in fact exist, though they often use smaller helicopters. A Google search on the term "heli taxi" yields thousands of results, and while a lot are probably irrelevant, the first few pages give ...
- 14.9k
41
votes
What helicopter has the most rotor blades?
The most blades I've seen are 8 on the Mi-26.
Source
But the highest theoretical lifting efficiency is achieved with the fewest blades and experiments have been done with single blade rotors (with a ...
- 105k
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