A Conversation for Ask h2g2

Helecopters

Post 41

Anonymouse

Shame on you. smiley - winkeye


Helecopters

Post 42

Paul the Brake

So are you saying that you think the helecopter could be moved or not? You obviously paid more attention than me smiley - winkeye


Helecopters

Post 43

Is mise Duncan

Yes it could be moved...but it would be a major effort. (Akin to pulling a family saloon on a flat road)

The question seems to be based on a misunderstanding:- Just because the helicopter is airborne doesn't make it any less massive. The _only_ differnce between pulling a flying helicopter and pulling one on the ground is the rolling resistance of the wheels making the latter case more difficult. However, wheels are amazingly efficient (we've been working on them for quite a while now smiley - smiley , so that difference is marginal.

(Note, I use the phrase "massive" instead of "heavy", as gravity is not involved in this.)


Helecopters

Post 44

Paul the Brake

Would't it be great if we could put this into practise on top of the Nat West building or somewhere. It could be the next H2G2 event like the rounders on Clapham Common with pics and everything smiley - smiley


Helicopters

Post 45

Is mise Duncan

If anyone can tell me the exact mass of a helicopter then I could knock up an on-line simulation, so that those of use who can't get to the Natwest tower could join in.
If not, never mind as I'm only really replying because the wrong spelling of "helicopters" was bothering me smiley - smiley


Helicopters

Post 46

Wand'rin star

Heredity strikes again smiley - smiley


Helicopters

Post 47

Anonymouse

Never having had a helicopter on a leash for a pet, and not likely ever having one in the future, I guess I'll never know for sure. smiley - biggrin

'Nonniesmiley - rose


Helicopters

Post 48

Is mise Duncan

Having rethought this, it strikes me that the "bowl effect" (posts passim.) would resist being moved forward as well as being tilted...therefore it would be more difficult to pull along an airbourne helicopter than one (with wheels obviosly) on the ground.
Even a small helicopter should be too massive for an average human to pull along on the ground - so the eventual 'answer' is no - you could not pull a helicopert along....


Helicopters

Post 49

Anonymouse

I dunno.. ever watched one wobble when someone tried to climb on one side? If things get (seemingly) lighter when you pull them through water (which is odd since water is heavier than air) then....

'Nonniesmiley - rose


Helicopters

Post 50

Gnomon - time to move on

Listen to Duncan and Tim. They know what they are talking about. If there is no wind, then the only thing stopping the helicopter from moving is air resistance which is small at low speed, so the helicopter will be as easy to tow as if it were sitting on the ground on a frictionless surface. It is possible to tow large weights if you are patient. I have towed a 40 ton barge. You pull on the rope and nothing appears to happen, but after about 5 minutes the barge starts to move. Once it is moving, it takes just as long to stop it.

If you just hold the rope that is hanging straight down from the helicopter and walk away, the rope will start to slope and the helicopter will come down slightly until you are pulling the helicopter along a lot and down slightly. Eventually, if the pilot doesn't increase the lift slighlty, the helicopter will touch the ground.

The tilt effect identified by Tim is real. As you pull the copter, it will tilt which will cause the copter to push in the opposite direction to the one you are pulling in. The only way to counteract this is to insist that the pilot works at keeping the copter level.

So the general answer is that ignoring the "tilt" effect, you can tow a helicopter.

Hot air balloons will not show the tilt effect. Because of their big surface area, they will be very much affected by light breezes, so all the above applies only in a dead calm day.


Helicopters

Post 51

Is mise Duncan

Two years from question to definitive answer...is this a record?


Helicopters

Post 52

Gnomon - time to move on

Duncan,

On careful re-reading of this thread, I see that you are right about the time involved. But I also see that between Nov 99 and Jan 01 you changed your mind. You fickle thing!

When I said, Duncan is right, I was agreeing with your former self, the pre-millennium DJ.

And why is my answer considered to be definitive? smiley - biggrin


Helicopters

Post 53

Is mise Duncan

I had to (hastily) change my mind because I have noticed a rather worrying trend: when I say something can be done, I am immediately assigned the task of doing it. I didn't fancy having to drag a helicopter around Dublin - even on a still and bright day like today. smiley - winkeye


Helicopters

Post 54

Gnomon - time to move on

Is it possible to drink thirty pints and remain conscious? smiley - winkeye


Key: Complain about this post