Helicopter ability question for those in the know..

Damn Dirty Ape

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Nov 1, 1999
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More specifically, can they do loops or rolls? (such as corkscrew, barrel, etc)..


We were just at a friends house and she claims that they had helicopters at a county air show a ways back that could do loops and all kinds of rolls. I'd tend to think this is BS, but don't know enough to call shens on her story to her..

Anyone out there know about helicopter abilities to let me know if the above acts are possible?

Also, I quoted that if a helicopter hovers in one spot for too long (not sure the definition of 'too long'), the air underneath can become unstable and it can drop like a rock.. True?
 

Evadman

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Feb 18, 2001
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Some helio's can do inverted manuvers, but only specialy equipped ones.
 

crab

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Yes they can...I've only seen military do them, though.
 

Heisenberg

Lifer
Dec 21, 2001
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I know the Apache can do loops and rolls and IIRC it's one of the only one's (or maybe the only one) that can.
 

LordMorpheus

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It is possible for a helicopter to loop, roll, even hoven inverted.

However, these maneuvers are usually limitied to R/C copters because of the inherent danger, and the whole passenger comfort thing.

Also, a helicopter has no need to be capable of inverted flight, so most "real" copters probably aren't.

There is a great video of an R/C copter going absolutely nuts floating around the internet, but I don't really want to dig a link out. Maybe someone else well before I decide to get around to it.
 

Damn Dirty Ape

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Originally posted by: LordMorpheus
It is possible for a helicopter to loop, roll, even hoven inverted.

However, these maneuvers are usually limitied to R/C copters because of the inherent danger, and the whole passenger comfort thing.

Also, a helicopter has no need to be capable of inverted flight, so most "real" copters probably aren't.

There is a great video of an R/C copter going absolutely nuts floating around the internet, but I don't really want to dig a link out. Maybe someone else well before I decide to get around to it.


Ok, thats cool, this person did'nt specify what type of helicopter but thought I would come to a place where some *would* know for fact :) That's neat!


question: When I think of inverted, I would think of the blades 'pulling' the craft in whatever direction, how could it achieve inverted hover when the 'pull' of the blades would be towards the earth?

 

novasatori

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Feb 27, 2003
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Originally posted by: Hellspawn
Originally posted by: LordMorpheus
It is possible for a helicopter to loop, roll, even hoven inverted.

However, these maneuvers are usually limitied to R/C copters because of the inherent danger, and the whole passenger comfort thing.

Also, a helicopter has no need to be capable of inverted flight, so most "real" copters probably aren't.

There is a great video of an R/C copter going absolutely nuts floating around the internet, but I don't really want to dig a link out. Maybe someone else well before I decide to get around to it.


Ok, thats cool, this person did'nt specify what type of helicopter but thought I would come to a place where some *would* know for fact :) That's neat!


question: When I think of inverted, I would think of the blades 'pulling' the craft in whatever direction, how could it achieve inverted hover when the 'pull' of the blades would be towards the earth?

The blades have tilt control.. they can stop them from pulling at all when inverted.

Also to the just falling question, I guess ti could happen but saying as none of the air beneath the blades is stable is it, how could it become <more> unstable? Also the lift comes from air above the blades being pulled through them, so I'd have to say no they can't just fall.

Edit: Unless you're talking about a weather phenomena ie wind shear.
 

Evadman

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Feb 18, 2001
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Originally posted by: novasatori
Also the lift comes from air above the blades being pulled through them, so I'd have to say no they can't just fall.
That is incorrect. The majority of the lift comes from the shape of the blade, just like a aircraft wing. TI is not a lift fan.
 

novasatori

Diamond Member
Feb 27, 2003
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Originally posted by: Evadman
Originally posted by: novasatori
Also the lift comes from air above the blades being pulled through them, so I'd have to say no they can't just fall.
That is incorrect. The majority of the lift comes from the shape of the blade, just like a aircraft wing. TI is not a lift fan.

Like an aircraft propeller, I realize this, but the air has to come thru the blades or it would stall.

Without more air to pull through there's no lift.


Its just a complex aircraft's engine with prop pitch etc turned vertical.
 

dderidex

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Mar 13, 2001
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Originally posted by: novasatori
Originally posted by: Evadman
Originally posted by: novasatori
Also the lift comes from air above the blades being pulled through them, so I'd have to say no they can't just fall.
That is incorrect. The majority of the lift comes from the shape of the blade, just like a aircraft wing. TI is not a lift fan.

Like an aircraft propeller, I realize this, but the air has to come thru the blades or it would stall.

Without more air to pull through there's no lift.


Its just a complex aircraft's engine with prop pitch etc turned vertical.

No, not like an aircraft propeller. Like an aircraft *wing*.

There is a reason helicopters are referred to as 'rotary wing aircraft'. Same principle that applies to planes applies to helicopters, only instead of the aircraft moving *forward* to generate lift over the wing, the "wing" itself is moving in circles.

It can pivot at the axel, which is how helicopters move at all. The 'blades' are rotated as they swing forward to generate less lift. Less lift over the 'front' of the wing and more over the 'back' of the wing means the aircraft tilts forward and slides that way.

By continuing the tilt on the blades, they can provide lift in the opposite direction entirely.

Also - the 'drops out of the sky' comment. What you are referring to there is Vortex Ring State. Basically, if the helicopter rapidly changes altitude, the downward force of the 'rotary wing' can create a loop on the edges of it whereby it's circulating the air it depressed down and to the sides. If this happens, the helicopter essentially loses all lift and drops from the sky. Wikipedia has an article on it
 

novasatori

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Feb 27, 2003
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Originally posted by: dderidex
Originally posted by: novasatori
Originally posted by: Evadman
Originally posted by: novasatori
Also the lift comes from air above the blades being pulled through them, so I'd have to say no they can't just fall.
That is incorrect. The majority of the lift comes from the shape of the blade, just like a aircraft wing. TI is not a lift fan.

Like an aircraft propeller, I realize this, but the air has to come thru the blades or it would stall.

Without more air to pull through there's no lift.


Its just a complex aircraft's engine with prop pitch etc turned vertical.

No, not like an aircraft propeller. Like an aircraft *wing*.

There is a reason helicopters are referred to as 'rotary wing aircraft'. Same principle that applies to planes applies to helicopters, only instead of the aircraft moving *forward* to generate lift over the wing, the "wing" itself is moving in circles.

It can pivot at the axel, which is how helicopters move at all. The 'blades' are rotated as they swing forward to generate less lift. Less lift over the 'front' of the wing and more over the 'back' of the wing means the aircraft tilts forward and slides that way.

By continuing the tilt on the blades, they can provide lift in the opposite direction entirely.

Also - the 'drops out of the sky' comment. What you are referring to there is Vortex Ring State. Basically, if the helicopter rapidly changes altitude, the downward force of the 'rotary wing' can create a loop on the edges of it whereby it's circulating the air it depressed down and to the sides. If this happens, the helicopter essentially loses all lift and drops from the sky. Wikipedia has an article on it


FYI Aircraft Propeller is a wing.

A helicopter engine is nothing more than a complex aircrafts engine turned vertical as I said.
 

Yossarian

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Dec 26, 2000
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Originally posted by: novasatori
FYI Aircraft Propeller is a wing.

A helicopter engine is nothing more than a complex aircrafts engine turned vertical as I said.

engineering quiz time, why does the shape of the prop change along its length?
 

novasatori

Diamond Member
Feb 27, 2003
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Originally posted by: Yossarian
Originally posted by: novasatori
FYI Aircraft Propeller is a wing.

A helicopter engine is nothing more than a complex aircrafts engine turned vertical as I said.

engineering quiz time, why does the shape of the prop change along its length?

because the inside rotates faster than the outside?