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Eh, he probably has a chain hoist from the ceiling. Anyone buying it had better have a chain hoist to manage those heavy attachments!
 

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the "AWOL member"
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maybe get it down the same way he got it up there?:hide::sidelaugh
 

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It will be lighter if you let the air out of the tires...
True. A 747 airliner when pressurized, weighs about a ton more than the take-off weight. How much does the air in the tires weigh?

When my users complain about the weight of their old laptops, I suggest they remove some files.:fing20:
 

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How much does the air in the tires weigh?
Well we can assume that a cubic foot of air weighs approximately 0.0807 lbs.
So if you take that divide by 12 you should come up with the weight of a cubic inch...
Ok thats sounding to difficult for me...

But I definately like the "remove some old files" from your laptop if you think it weighs to much!!!!!

Merrie
 

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Well we can assume that a cubic foot of air weighs approximately 0.0807 lbs.
So if you take that divide by 12 you should come up with the weight of a cubic inch...
Ok thats sounding to difficult for me...
I think it is a bit more complicated than that. In my example with the 747, they don't remove all the air, they just remove the extra compression to come up with the 1 ton figure. Now... they don't compress the air in the cabin nearly as much as you might for a tire so we would need to know the weight to compression ratio.

It might be easier to just weigh a full tire and then let out the air and weigh it again.
 

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A 747 airliner when pressurized, weighs about a ton more than the take-off weight

Umm... you're gonna have to explain this.... a 747 cabin is NEVER pressurized above 1 atmosphere... it's normally at 1atm when it's on the ground.... 1ATM is actually ambient pressure - therefore there is no "extra weight" due to air in the cabin.

At altitude, cabin pressure may be set to between 7000-8000 feet altitude. When the plane is flying at 35,000 feet, the cabin is technically pressurized in relation to the outside, but THERE IS NO MORE AIR in there than there was on the ground... in fact there is less, because of the reduced pressure (7000-8000 equ. feet alt.).... so how does the 747 have a Ton "more" air in there?

Having looked this up now, what you are actually referring to is "mass". There is a ton of air mass in the cabin, at sea level cabin pressure. This relates to the inertia of air that's in the cabin. But that's at sea level. In flight, it's not "more"... it's actually "less" than what the mass of equivalent volume of air would be at 1atm. In fact, the approx. mass of the air inside a 747, when the cabin is set to 7000 feet, is about 0.86 of a tonne - but again, we're talking about mass, not weight.... they're not the same.

cheers!
 

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High Mass?... I don't get it...

1'st thing I thought of when I saw it was: Mile High Club... but that's another story...
 

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Umm... you're gonna have to explain this....
OK, I guess I should not believe what I hear on television. I was watching a show that talked about the 747 and that the pilot had to factor an additional ton above take-off weight for pressurizing the cabin.

Now, I'm not a pilot and don't know if the cabin pressure ever exceeds atmosphere whatever it may be where they take-off from. I think the air pressure at sea level is around 15 lbs and 15 lbs of differential pressure seams like a lot to me but then the way my ears and sinuses react on flights, it feels like more than 15 lbs.
 

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The owners manual
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But then you have to take the weight of the air that is let out of one tires times Pi. (Pi is 3.14159), to get the weight of air left in the tire.

Dick
 

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If your flyin at around 8,000' as suggested and the cabin door won't open... Do you hit it with the mile high club???

Good one!

LOL!!!!
 

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Boyd,Boyd---Just look at what you started.Now their weighing air.:biglaugh::biglaugh:
 
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