Humor Abuse of units

[Linguofreak]

It's amusing the fun you can have by parsing units of measurement in ways in which they were not meant to be parsed.

For instance, a 747 has a fuel efficiency of about 5 gallons/mile.

Since gallons are a unit of volume, and miles a unit of length, we get a unit of area: The 747 has a fuel efficiency of 11 square millimeters.

 

[Andy44]

Okay, let me wrap my head in duck tape so it doesn't explode...

The smaller the area, the more effiecient the jet is...

So if the area is an infinitely small point, than the jet is a perpetual motion machine...

And if the area is an infinite 2D plane, then the jet has an infinite fuel consumption...

Okay. So there must be some other conceptual meaning to this.

BTW, specific impulse, measured in seconds, is a real-life example of this. What does it mean conceptually to measure it in seconds? This:

If you burn one lbm of propellant at a rate such that it produces one lbm of thrust, it will burn for Isp seconds...

 

[Bj]

Since gallons are a unit of volume, and miles a unit of length, we get a unit of area: The 747 has a fuel efficiency of 11 square millimeters.

I guess I do not get the logic, or maybe I am missing something in a higher level of math...

what?

 

[ex-orbinaut]

It's amusing the fun you can have by parsing units of measurement in ways in which they were not meant to be parsed.

For instance, a 747 has a fuel efficiency of about 5 gallons/mile.

Since gallons are a unit of volume, and miles a unit of length, we get a unit of area: The 747 has a fuel efficiency of 11 square millimeters.

h::lol::rofl::rofl::11sign:

Heard about Seat per Mile Cost, but this takes the cake!

---------------------------------------------------------------

Looking at the post below, I think that between you two you have invented a new way of doing IATA statistics. You should patent it!

I love this thread!

 

[martins]

Since gallons are a unit of volume, and miles a unit of length, we get a unit of area: The 747 has a fuel efficiency of 11 square millimeters.

Well, it's not so weird: this is the cross section of a long thin cylinder of fuel consumed along distance travelled, i.e. stretching all the way from the plane's origin to its destination. Scary, if you think about it ...

 

[TSPenguin]

That could reduce pilots handbooks to simple "Just follow the fuel."

 

[PeterRoss]

I don't think it's more weird than measuring distance in light years.

 

[Ark]

I don't think it's more weird than measuring distance in light years.

"It'll make the Kessel Run in less than 12 parsecs."

 

[PeterRoss]

"It'll make the Kessel Run in less than 12 parsecs."

Hey, it's classic, you can't just laugh at it! :lol:

 

[Andy44]

Well, it's not so weird: this is the cross section of a long thin cylinder of fuel consumed along distance travelled, i.e. stretching all the way from the plane's origin to its destination. Scary, if you think about it ...

Ah, yes, of course. And that really makes sense when you put it that way. I'm going to determine the cross-section of my pickup truck's "fuel cylinder" tomorrow!

 

[Urwumpe]

Well, it's not so weird: this is the cross section of a long thin cylinder of fuel consumed along distance travelled, i.e. stretching all the way from the plane's origin to its destination. Scary, if you think about it ...

Should make run planes on internet cables, this could maybe save some money for transatlantic communication.

 

[Sky Captain]

Which vehicle has the fattest fuel cylinder? :hmm:

 

[Urwumpe]

Which vehicle has the fattest fuel cylinder? :hmm:

I'd guess the Crawler Transporter at KSC.

150 gal/mi --->333 mm²

 

[agentgonzo]

In a similar fashion, torque can be measured in Joules. I've come across a few more previously but I can't remember what they are at the moment.

 

[Urwumpe]

This is just the same kind of abuse as measuring specific impulse in seconds - and even the rather accurate m/s is not specific impulse (But average exhaust velocity). Specific impulse is impulse per (fuel) mass, so the accurate unit is N*s/kg... or lb*s/slug

Especially note that lb ≠ lbf

1 lbf = g * 1 lb

lb ≡ 4.448 230 531 N
lbf ≡ 4.448 221 615 2605 N

 

[ex-orbinaut]

In a similar fashion, torque can be measured in Joules. I've come across a few more previously but I can't remember what they are at the moment.

Lots of good ones on the old rotating disk type flight computers (ARC-1 or E6B), where if you were not careful you could end up converting meters to lbs of fuel, and specific gravities to density altitudes.... liters into hours...

 

[Hielor]

Related: http://www.neatorama.com/2009/01/30/fun-and-unusual-units-of-measurements/

 

[Urwumpe]

The listing does not list the "Garn scale".

 

[n72.75]

"It'll make the Kessel Run in less than 12 parsecs."

He knows a shortcut that is a little less then 39 lightyears.