[Tiresias]

You are standing under the spinning rotors of a large helicopter. There is no wind, other than that generated by the helicopter. It is raining. Do you get wet?

[MarkLT1]

Yes

[Tiresias]

Dumb question? Wet? Don't leave me hanging like that!

[Dakar the Fourth]

My opinion is worth jack, but I say yes.

[zro]

I would say he means wet. Where is the rotor going to pull air that doesn't have any moisture in it?

[paul w]

From the sky above AND from the ground below?

[wallinbl]

Doesn't the helicopter accelerate the downward flow of air? It's not like it's blowing the air upward, which could possibly deflect the rain.

Or, is your question whether the blades are going so fast that a rain drop couldn't possibly get through without hitting a blade?

[Tiresias]

Originally Posted by wallinbl 

Doesn't the helicopter accelerate the downward flow of air?

Might the water still be deflected? Like trying to squirt a water pistol through an electric fan—could you wet someone sitting behind it? in front of it?

[zro]

No, but you could wet somebody sitting in front of it.

I can see how the bulk of water might impact with the blades and be flung outwards, but I'm sure enough moisture comes down to get you wet.

[Mrjinglesusa]

This is almost as bad as the "Will a plane take off if it's on a treadmill". BTW, did you all see that Myth Busters proved once and for all that a plane WILL take off if it's on a treadmill?

[voodoo]

Originally Posted by Mrjinglesusa 

This is almost as bad as the "Will a plane take off if it's on a treadmill". BTW, did you all see that Myth Busters proved once and for all that a plane WILL take off if it's on a treadmill?

All I saw was 'mythbusters' changing the premise of the question so it would be answered the way they wanted it to be answered.

[osiris]

imo Mythbusters has gone downhill the past season or so. Sorry, but it has become pure Hollywood schlock.

[Dakar the Fourth]

Originally Posted by osiris 

imo Mythbusters has gone downhill the past season or so. Sorry, but it has become pure Hollywood schlock.

I don't feel they're entirely to blame though. I think they took the original premise as far as it could go. Now all that's left is exploring the illusion of Hollywood science.

[MarkLT1]

Ok, so lets assume the helicopter is sitting on a huge treadmill, which speeds up whenever a nearby ant farts OR if the groundhog sees his shadow after extending winter for 6 weeks. If it begins to rain, and a tree falls over in the woods, does the rabbit trapped under the fallen tree make a sound if no one is there to see him? Oh, and is this a dumb question?

[Don Pickett]

Originally Posted by voodoo 

All I saw was 'mythbusters' changing the premise of the question so it would be answered the way they wanted it to be answered.

Actually, Mythbusters got it right, in the sense that while it's theoretically possible for the plane not to be able to take off on a treadmill, it's not realistic. You'd need an enormous treadmill in order to deny airstream over the plane's wings and that just isn't gonna happen.

To answer the abovw question, you'd still get wet. In fact, you'd get soaked, but instead of the water just coming straight down it would be coming at you from all sides.

[Tiresias]

Originally Posted by MarkLT1 

Ok, so lets assume the helicopter is sitting on a huge treadmill...

So far so good. I'm already smiling...

which speeds up whenever a nearby ant farts OR if the groundhog sees his shadow after extending winter for 6 weeks. If it begins to rain, and a tree falls over in the woods, does the rabbit trapped under the fallen tree make a sound if no one is there to see him? Oh, and is this a dumb question?

Epic humor fail.

This post reminds me of a sprinter clearing the first hurdle, only to plough violently into the next, and the one after that, and the one after that, and the one after that...

[MarkLT1]

Originally Posted by Tiresias 

So far so good.

Epic fail.

This post reminds me of a sprinter clearing the first hurdle, only to plough violently into the next, and the one after that, and the one after that, and the one after that...

Awesome! Thats about how your question made me feel

[Andy8]

Originally Posted by Tiresias 

You are standing under the spinning rotors of a large helicopter. There is no wind, other than that generated by the helicopter. It is raining. Do you get wet?

How many RPM are the main rotors doing? How many main rotor blades?

[osiris]

Originally Posted by Dakar the Fourth 

I don't feel they're entirely to blame though. I think they took the original premise as far as it could go. Now all that's left is exploring the illusion of Hollywood science.

The premise is fine - I love what they do. But it's the stringing out and mindless banter in-between that kills me.
The show would be about 10 minutes long if you were to cut the fat out.

Exploring Hollywood science would be a winner!

[Dakar the Fourth]

Originally Posted by osiris 

The premise is fine - I love what they do. But it's the stringing out and mindless banter in-between that kills me.
The show would be about 10 minutes long if you were to cut the fat out.

True, true. They also seem to require model tests for everything now. Was it always that way?

I really hated it for a while there where it seemed like they weren't allowed to "call it" at the testing ground, but wait for the blue table.

[Don Pickett]

Originally Posted by Dakar the Fourth 

True, true. They also seem to require model tests for everything now. Was it always that way?

They've explained the model tests before. The big reason is the model tests save them money and time, as they can weed out anything which clearly doesn't work and concentrate on what does.

But let's be truthful here: we all know why we watch the show.

[Dakar the Fourth]

Originally Posted by Don Pickett 

They've explained the model tests before. The big reason is the model tests save them money and time, as they can weed out anything which clearly doesn't work and concentrate on what does.

But let's be truthful here: we all know why we watch the show.

That makes sense if what they're trying to do is expensive. But for something like the Knight Rider one, the model test pretty much negated the need for a real test. What could possibly change?

[Don Pickett]

Originally Posted by Dakar the Fourth 

That makes sense if what they're trying to do is expensive. But for something like the Knight Rider one, the model test pretty much negated the need for a real test. What could possibly change?

Just because it works in the model doesn't mean it works in the real world. The models serve to weed out the stuff which clearly won't work at all. Once you narrow it down, it's time to see how it works in real life. The physics can be sinificantly different.

Additionally, the models halp with safety. Fr'instance, if the model for the Knight Rider stunt had shwn the car catapauled straight through the cab of the semi, they would've known they were facing real danger.

[MarkLT1]

Maybe the Mythbusters can determine if the OPs question was dumb?

[TETENAL]

Originally Posted by voodoo 

All I saw was 'mythbusters' changing the premise of the question so it would be answered the way they wanted it to be answered.

There are two possible interpretations of the "plane on a treadmill" question. The one Myth Busters picked and another one which is a logical paradox. Since the latter one is impossible to test, they picked the only possible premise.

[turtle777]

Originally Posted by Tiresias 

Is this a dumb question?

Yes, definitely

-t

[Dakar the Fourth]

Originally Posted by Don Pickett 

Just because it works in the model doesn't mean it works in the real world. The models serve to weed out the stuff which clearly won't work at all. Once you narrow it down, it's time to see how it works in real life. The physics can be sinificantly different.

I agree in principle, but not for this experiment. Further, did they conduct scale test when they smashed that car with two tractor trailers simultaneously?

Originally Posted by Don Pickett 

Additionally, the models halp with safety. Fr'instance, if the model for the Knight Rider stunt had shwn the car catapauled straight through the cab of the semi, they would've known they were facing real danger.

I understand why it's done. I don't agree it needs to be done for every experiment.

There was no reason to suspect some kind of trickery from an 80s network show. Which is what made the scale test such a farce.

[Don Pickett]

Originally Posted by Dakar the Fourth 

There was no reason to suspect some kind of trickery from an 80s network show. Which is what made the scale test such a farce.

It may also be a money saving meaure put in Discovery, who may have told them they have to model test every scenario first to cut down on build times. It could also be a stipulation from the insurance company, for safety reasons. I know they've had a number of problems with their insurers.

[Dakar the Fourth]

Either way, the point is, it's not always interesting, but they always use it as filler. It's not they they do it, it's that they air it.

[olePigeon]

Ah, this is simple. You have the V-22 Osprey rotate its rotors until it crashes, then the water from the fire hose makes you wet.

[Tiresias]

The Osprey is an interesting-looking machine. Why don't they build one with jet-engines?

Anyway, to conclude: If the time it takes a drop of rain to pass through the rotors' plane of rotation is greater than the time it takes the rotors to complete half a rotation (or a quarter, in the case of a helicopter with four rotors) then every drop of rain will be scattered. However, one will still get wet from the moisture-laden wind and downdraft.

There. You are now free to devote the thread to mocking my stupidity with plane-on-treadmill jokes.

[olePigeon]

What if it's in a vacuum?

[Railroader]

An African swallow or European swallow?

[@pplejaxkz]

I'd say you'd get a little wet.

[design219]

Originally Posted by Tiresias 

...the time it takes a drop of rain to pass through the rotors' plane of rotation...

Well, the thing is the rain is not going to be falling at its normal rate when it gets close to the helicopter rotors. It will speed up tremendously because the air is moving so fast (downward).

My first thought was that here is no way a drop of rain is going to be flung sideways by a rotating blade at a 90 degree angle to the force of the downward wind. And of course the blades are designed to deflect down.

But, just possibly, the ground effects (which make helicopter thrust more effective close to the ground) just might do such a thing since the air has to change direction in close proximity to the ground.

But then, inertia of the heavier rain would tend to keep it going to the ground.

Yeah, you get wet.

[Kevin Dunahee]

Originally Posted by Railroader 

An African swallow or European swallow?

Oh, well even I don't know that. *gets ripped by an unseen force into the distance*

[slpdLoad]

Actually, in order for the helicopter to be stationary but with the rotors spinning, the blades are simply pitched so as to not produce much lift, so you will be getting a lot wetter when the helicopter tries to take off and really starts throwing air down at you.