How cheap is your airplane

forseth11

forseth11

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Forseth11
Hello Pilots of America.
I am curious as to how your airplane (either one you fly or own) preforms based on fuel burn and speed.

Go ahead and post your average cruise TAS (knots) and divide that by your cruise fuel burn (gallons). Then multiply that by how many souls you can carry. Lets call this number "economic rating".
Don't forget to include your aircraft type.
The higher the number, the better.

Also, feel free to add the following after your aircraft's name: (TAS, fuel burn, seats)

I'll start:
Cessna 150: 28.3 er
(85, 6, 2)

Mooney M20E: 65.9 er
(140, 8.5, 4)

I am really curious to see how cheap everyone's airplane is based on speed and people you can carry.
 
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Mine's real cheap, I just watch 'em fly over the house. o_O:)
 
8

120 @ 15GPH, normally just be me or one other.

For the plane

120 @ 15, real world 4 seats not including the midget third row, so 32
 
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Not sure the calculations are right here: each SOUL on board likely has two SOLES.
 
Bellanca1730 is 43 (150, 14, 4)

if we are allowed to comment further on the topic; it looks like you are trying to simplify 'airplane cheapness' - commendable. And I am sure you realize so many other things deserve consideration (but would really cloud your goal)
Purchase price
Maintenance costs
potential selling price
to name but a few
 
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43 to 50 for the RV-12, depending on how big a hurry I'm in.

I would point out that this range puts it in the same class as the Cirrus, while the two are two seats, 70 knots and well over $400K apart. So... the number is pretty much meaningless, IMHO.
 
M20-C, 65.8 ER (148 ktas, 9 gph, 4 seats)

Much closer to the E model than I would have guessed.
 
I think any such factor should also incorporate the opportunity cost of the invested capital. An airplane that is extraordinarily fast, while sipping a pittance in fuel is no "bargain" if you had to pay through the nose to buy the ride imo.
 
GRG55 said:
I think any such factor should also incorporate the opportunity cost of the invested capital. An airplane that is extraordinarily fast, while sipping a pittance in fuel is no "bargain" if you had to pay through the nose to buy the ride imo.
Click to expand...
You're right. Should of made a calculation involving many more things and use usable weight instead, and include range, and stuff like that. Maybe make a few separate formulas which will help easily compare airplanes for what kind of things you want it to do.
 
This idea has piqued me for a very long time; it seems that a formula could be developed to maximize desirable characteristics with respect to the undesirable ones. and adjusted to an independent variable
9e.g. cost). Your first-cut attempt looks good, but might need refining.
 
Piper arrow, 52
(130, 10, 4)

Sent from my SAMSUNG-SM-N910A using Tapatalk
 
I kind of think your talking about pa46 class. I have less in this plane than I did the Columbia 350, 2006 I had before it. These older ones are quite affordable. Even a a36 beech is going to be in the 250g neightborhood.
 
GRG55 said:
I think any such factor should also incorporate the opportunity cost of the invested capital. An airplane that is extraordinarily fast, while sipping a pittance in fuel is no "bargain" if you had to pay through the nose to buy the ride imo.
Click to expand...

Hmmm. Two ways to think about that: I'd argue for using deprecion as the primary metric. I own a 1971 C172L. Just bought it for a few grand below a reasonable market price. It will likely hold value for a decade. In that sense, the capital sunk into the plane is locked up, so you can use that opportunity cost as a metric, too - but seems like depreciation is more significant.

C172L, power flow exhaust: 45
90 TAS, 8gph, 4 souls.


AND - thanks for this, now you got me thinking about a Mooney...
 
I think for simplicity's sake, it's a fancy little metric. Obviously it's one of them 'just for fun' things as opposed to a truly useful measure. Many variables unaccounted for... but kinda nifty to boil it down to 3 things to get an efficiency rating.
 
I really try to not think about such things, blissful ignorance you know.
C175 180/CS 122 at 10 gph.
Almost always my wife and I.
Not very efficient, but we travel around the country at this stately speed.
Noticed a new gas station being built just inside town. They're advertising ethanol free fuel.
That would be the first one in El Paso, and would reduce my fuel bill.
Dave
 
C-172C. 95kts, 8gph, 4 (well really three adults sized...but I'll use four any way) : 47.5
 
M20J @ 155kts, 11gph: 56.4
M20J @ 145kts, 8.5gph: 68.2
Horizon 180 @ 19kts, 0gph: infinite, but you had better find some thermals to go XC
 
forseth11 said:
You're right. Should of made a calculation involving many more things and use usable weight instead, and include range, and stuff like that. Maybe make a few separate formulas which will help easily compare airplanes for what kind of things you want it to do.
Click to expand...
You'll quickly discover that your most "economical" airplane is a 747. There is a reason airlines don't fly small aircraft much. It's not speed. In miles per passenger gallon, a full 737 beats a 172.

Bad statistic. Maybe divide the number of usual passengers instead of capacity....
 
MAKG1 said:
Bad statistic. Maybe divide the number of usual passengers instead of capacity....
Click to expand...

Uh, I think you meant multiply?

Bill Jennings said:
M20J @ 155kts, 11gph: 56.4
M20J @ 145kts, 8.5gph: 68.2
Horizon 180 @ 19kts, 0gph: infinite, but you had better find some thermals to go XC
Click to expand...

OK, usual number of passengers:

M20J @ 155kts, 11gph: 42.3
M20J @ 145kts, 8.5gph: 51.2

No change for the 180, it is a single passenger aircraft
 
I agree with the post above; should divide by passengers not multiple. More passengers for fuel burn is more efficient.
 
180 kts at 6.5 gph.
2 seats

Multiple empty seats don't contribute to a valid meaningful economic rating.
 
scorpio said:
I agree with the post above; should divide by passengers not multiple. More passengers for fuel burn is more efficient.
Click to expand...

Depends on what the metric is to be? The OP metric is passenger miles per gallon. Your proposal would be miles per passenger gallon.
 
Velocity 173 RG- (64)
160 KTAS, 10 GPH, 4 seats.

Glasair 1 FT- (39)
168 KTAS, 8.5 GPH, 2 seats.
 
RV-6A - 160 KTAS, 8 GPH, 2 seats = 40.

I think there is too much "seat bias" in this calculation. How about using (Useful load Lbs / 100) / # of seats to normalize this?

Then I'd have (160/8) * (700/100/2) = 70. Some planes with four seats can't be loaded with four full size humans but they get credit in your calculation.

OR

Forget the seats completely and use the useful load / 100. (the divide by 100 is only to keep the result smaller.
 
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Please tabulate these when done for 'review at a glance'.
Put it in Excel and maybe later someone will add the other factors mentioned.
 
Bonanza V35A TC: 195/16.5*4 = 47.3
(195, 16.5, 4)

Cherokee Six PA32-260: 135/12*6 = 67.5
(135, 12, 6)
 
Cardinal w/150 hp
110 kts with 2 people burns 7.5 g/h of mogas
Economic rating of 29.3
that's actually better than my Willys truck
 
Current airplane: 44.3 (155 / 14 * 4)

Soon-to-be airplane: 38.4 (160 / 25 * 6)
 
Was just going to post that....
true_costs_speed.jpg
 
Another M20E data point:
152 kts / 9.8 gph * 4 Persons = 62
 
747-400: 495 knots / (20,000 lb/hr / 6.8 lb/gal) * 400 passengers = 67.3.

And that's using some conservative estimates. You can squeeze a lot more than 400 passengers into an ER if you're willing to ignore evacuation and cram them in. And the 747-8 will have even higher specs.

The statistic is silly. A 747 is NOT more economical than a 172 unless you have 400 people wanting to fly all the time.
 
182Q 130 knots, 13 GPH, 4 seats =40
Conquest I 255 knots, 65 GPH, 8 seats= 31.3
 
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