What's your tons per mile

[RedDevil]

I must have the first lung type as I run into trouble at even 8000 feet. Dropping things, getting desorientated and so. I don't like flying as the cabin pressure is lower than I like.

But I'm almost always at sea level. Things might improve if I'd stay out in the mountains and get used to height.

[NeilBlanchard]

Thanks for this thread, Mike! I hope we can take Cd into account with this, as well? The mass of the air is much more than one would guess, but obviously a low drag car causes a significantly lower disturbance of that mass.

Can I repost your numbers, please? This will be quite useful in any forum discussing car efficiency.

[Fat Charlie]

You need a new hobby, basjoos!

[Hersbird]

I have a condition similar to the black lung coal miners get. Mine is called donut lung, I don't knowknow if it's all the powered surgar or what but I seem to huff and puff just getting off the couch.

[basjoos]

Originally Posted by RedDevil

I must have the first lung type as I run into trouble at even 8000 feet. Dropping things, getting desorientated and so. I don't like flying as the cabin pressure is lower than I like.

But I'm almost always at sea level. Things might improve if I'd stay out in the mountains and get used to height.

These lung types are referring to healthy lungs.

The way that first lung type works is that it is finely tuned and highly efficient at the altitude where you spend most of your time, but it loses efficiency quickly and has problems with altitude sickness as you get into thinner air. It can adapt to thinner air, but you have gradually work up to it over a period of days to weeks.

The second lung type is roughly tuned and not as efficient as the first type at its normal altitude, but isn't affected much and is slow to lose efficiency as you get into thinner air. I read about the lung types in an article I found in the 80's about mountain climbing and the effects of rapid increases in altitude. The first guys who climbed Everest without oxygen equipment obviously had the second lung type.

[basjoos]

When we extend tons per mile to include the effects of humidity, it gets more complicated since the amount of water vapor that a cubic foot of air can contain increases with temperature, but I found a calculator to do this.

Air Density Calculator

At sea level, 70 degrees F, and at 0% RH, I get 3.94 tons/mile
The same at 100% RH is 3.90 tons/mile
For a change of 0.04 tons/mile or 80 lbs/mile

At sea level, 100 degrees F, 0% RH, it is 3.73 tone/mile
The same at 100% RH is 3.64 tons/mile
A change of 0.09 tons/mile or 180 lbs/mile

At sea level, 0 degrees F, 0% RH it is 4.54 tons/mile
The same at 100% RH is 4.54 tons/mile
The value is unchanged since the air holds almost no water vapor at this temperature.

According to the calculator, you have to get above 5 degrees F before the air holds enough water vapor for the relative humidity to start affecting the air density.

Neil. you can repost the numbers.