Saving gas at 45k

[caldera]

I get the joke that it's a reference to Challenge. I'm just saying the PREMISE the joke is based on is wrong.

The D-11 with full gas and a drop tank has 47 minutes flying time on military power.  As can be seen on the clipboard, there are 21 minutes remaining.  I climbed the entire time on military power.  I didn't film the sortie but rest assured, 1k to 45k feet took quite a bit longer than 26 minutes. 

It was a joke of course, but thank you for your expert musings on gas mileage theory.
As stupid as the premise is, it is correct.  You?  Not so much. 

[Krusty]

The D-11 with full gas and a drop tank has 47 minutes flying time on military power.  As can be seen on the clipboard, there are 21 minutes remaining.  I climbed the entire time on military power.  I didn't film the sortie but rest assured, 1k to 45k feet took quite a bit longer than 26 minutes. 

It was a joke of course, but thank you for your expert musings on gas mileage theory.
As stupid as the premise is, it is correct.  You?  Not so much. 

Big words from somebody mouthing off, eh?

You're plain wrong, caldera. You're not AT military power. You're barely making 25" MAP... That means the air is so thin your engine cannot begin to produce max cruise, let alone "military power" -- you try running the same settings at sea level (throttle back to match the gauges, they actually mean something and are not for pretty decoration) you get 70+ minutes with internal and a drop tank.

You drop the tank and you still have over 60 minutes at 25" MAP...

Considering you are down to 46 gallons of fuel out of almost 400 gallons, you've got 1/10 your total fuel left (also note your fuel gauge in the picture, about 1/8 internal -- you're sucking fumes mate).


It's not a matter of being in the thin air. It's a matter of that thin air bottlenecking your engine's potential power. You throttle back to match those settings (which I just did offline to get the times I listed above) and you'll see how wrong you are.

You take off anywhere with 2 identical planes, one levels at 15 (or even 20) K, the other climbs up to 45k.... The one that levels off faster and MATCHES the decreasing RPM and MAP of the one going to 45K will get there faster, in a better position, and have more fuel when they enter the fight.

[Dawger]

It doesn't matter what your true air speed at 45k is... How much fuel are you burning (GPH)?


P.S. You burn off more fuel getting that high than you would if you leveled at (say) 20K and cruised from there. You'd get to the fight and back faster as well.

So now we are in a discussion of endurance versus range.

What is the critical altitude for the P47? Above that then your statement regarding the engine being able to produce less power with altitude is true but range will dramatically increase because of true airspeed. Below that altitude the engine can produce sea level power

Pilots in general are referring to distance traveled when discussing fuel economy. Loiter time is normally a side issue. Maximum loiter time in a turbo or supercharged piston aircraft is an interesting side discussion but higher is better to a certain point.

[caldera]

Big words from somebody mouthing off, eh?

You're plain wrong, caldera. You're not AT military power. You're barely making 25" MAP... That means the air is so thin your engine cannot begin to produce max cruise, let alone "military power" -- you try running the same settings at sea level (throttle back to match the gauges, they actually mean something and are not for pretty decoration) you get 70+ minutes with internal and a drop tank.

You drop the tank and you still have over 60 minutes at 25" MAP...

Considering you are down to 46 gallons of fuel out of almost 400 gallons, you've got 1/10 your total fuel left (also note your fuel gauge in the picture, about 1/8 internal -- you're sucking fumes mate).


It's not a matter of being in the thin air. It's a matter of that thin air bottlenecking your engine's potential power. You throttle back to match those settings (which I just did offline to get the times I listed above) and you'll see how wrong you are.

You take off anywhere with 2 identical planes, one levels at 15 (or even 20) K, the other climbs up to 45k.... The one that levels off faster and MATCHES the decreasing RPM and MAP of the one going to 45K will get there faster, in a better position, and have more fuel when they enter the fight.

By saying military power, I mean full throttle.  I'll leave all the technicalities to you of course.  If two identically equipped jugs take off (while maintaining full throttle) and one levels at 20k, while the other levels at 45k; then the one flying at 45k will be in the air longer.  There you have it - saving gas.  I'll leave you the last word as you have to be right, even in a joke thread.

[grizz441]

The joke actually originated at the foolish implication that there was any actual benefit from flying that high to save gas in the first place.  There is no doubt you can fly farther climbing that high and cruising but the application in the MA is non existent, unless of course, you are trying to set some sort of record by flying across the entire map three times.

[lyric1]

The joke actually originated at the foolish implication that there was any actual benefit from flying that high to save gas in the first place.  There is no doubt you can fly farther climbing that high and cruising but the application in the MA is non existent, unless of course, you are trying to set some sort of record by flying across the entire map three times.

Well lets put some context to this entire point. I believe the joke stemmed from this statement.



From this thread.  http://bbs.hitechcreations.com/smf/index.php/topic,278886.0.html

If it is taken out of context with only partial portions posted on the BBS it would appear laughable. However when shown in it's entirety by reading the rest of the thread. Not so much.

[grizz441]

"Flying at 30k is a great way to save on fuel."

ROFL.

That never gets old.  Thx for the laugh lyric.   

[Masherbrum]

 

[grizz441]

 

[EskimoJoe]

Have you guys ever taken a thin slice of butter, tossed it into the bottom of an empty soda box, and watched your dog stick its head in to try and get it? Yeah, this thread is exactly like that.

[SectorNine50]

"Flying at 30k is a great way to save on fuel."

ROFL.

That never gets old.  Thx for the laugh lyric.   

I must have missed something...

Isn't this why most missions over the Atlantic occurred at high alt?  You can generally go further on less fuel at higher altitudes...

[grizz441]

I must have missed something...

Isn't this why most missions over the Atlantic occurred at high alt?  You can generally go further on less fuel at higher altitudes...

So go save some fuel and fly at 30k then if it makes so much sense.

[Little Dragon]

  So 45k, wonder how that differs from saving fuel at 30K...   

[SWkiljoy]

 

[SectorNine50]

So go save some fuel and fly at 30k then if it makes so much sense.

No need to be an arse about it, explain to me why it doesn't make sense.  Isn't it true that at 30k you can go further on the same amount of fuel than 15k?

I'm not saying it's something that needs to be done in-game...  I don't think there are many 3 hour missions out there that require that kind of fuel conservation.  And perhaps that's why that quote is considered funny.

It is very clear that I have missed something.