Posted April 06, 2017
After having run out of fuel multiple times on the return to the airbase (I use the historical fuel quantity option) I began to wonder if, perhaps, there was an optimal altitude for fuel consumption. There doesn't seem to be any for this sim, so I conducted tests at various altitudes, and was rather surprised with the results.
I ran three flights each at 10,000; 15,000; 20,000; 25,000; 30,000 feet. The starting base was Podington; the target Basdorf, for a total flight distance of 1,204 miles. Navigation difficulty was set to flawless (to eliminate that variable) and weather set to "light" (to eliminate storms obscuring the target and necessitating a "go-around"). The payload was 6x 1,000 lb General Purpose. And both flak and enemy fighters were disabled. Starting fuel quantity was approximately 410 gallons.
I recorded remaining fuel once at the target, and a second time once back at the airbase. Within each altitude group there was a surprising variation, considering the attempt at removing variables from the experiment. The raw data will be at the end; the averages are as follows:
(distance) (remaining at target) (remaining at base)
10,000 -- 263.3 -- 66.7
15,000 -- 271.7 -- 91.7
20,000 -- 283.3 -- 116.7
25,000 -- 310.0 -- 150.0
30,000 -- 298.3 -- 141.7
I'd also made a second set of three flights at 25,000, adjusted propeller pitch and manifold pressures based upon an article I'd read concerning this sim (can't remember the URL; sorry). I had high hopes for this, but was quite disappointed:
25,000* -- 311.7 -- 165
There was very little difference under payload, although I did see a minor increase for the return leg.
At the moment it seems that the most economical altitude is 25,000 feet (at least in terms of 5,000-foot blocks). It is possible that carrying a lighter payload --say, 4,000 pounds rather than 6,000 pounds-- could result in the higher altitudes being more fuel efficient. I'll have to try that another day.
************************************************************************************************************** ***********
altitude: fuel remaining at target/fuel remaining at base arrival
10,000: 280/75 -- 250/60 -- 260/65
15,000: 290/90 -- 250/85 -- 275/100
20,000: 325/140 -- 275/110 -- 250/100
25,000: 300/150 -- 325/150 -- 305/150
25,000* 325/175 -- 310/160 -- 300/150
30,000: 300/145 -- 300/140 -- 295/140
I ran three flights each at 10,000; 15,000; 20,000; 25,000; 30,000 feet. The starting base was Podington; the target Basdorf, for a total flight distance of 1,204 miles. Navigation difficulty was set to flawless (to eliminate that variable) and weather set to "light" (to eliminate storms obscuring the target and necessitating a "go-around"). The payload was 6x 1,000 lb General Purpose. And both flak and enemy fighters were disabled. Starting fuel quantity was approximately 410 gallons.
I recorded remaining fuel once at the target, and a second time once back at the airbase. Within each altitude group there was a surprising variation, considering the attempt at removing variables from the experiment. The raw data will be at the end; the averages are as follows:
(distance) (remaining at target) (remaining at base)
10,000 -- 263.3 -- 66.7
15,000 -- 271.7 -- 91.7
20,000 -- 283.3 -- 116.7
25,000 -- 310.0 -- 150.0
30,000 -- 298.3 -- 141.7
I'd also made a second set of three flights at 25,000, adjusted propeller pitch and manifold pressures based upon an article I'd read concerning this sim (can't remember the URL; sorry). I had high hopes for this, but was quite disappointed:
25,000* -- 311.7 -- 165
There was very little difference under payload, although I did see a minor increase for the return leg.
At the moment it seems that the most economical altitude is 25,000 feet (at least in terms of 5,000-foot blocks). It is possible that carrying a lighter payload --say, 4,000 pounds rather than 6,000 pounds-- could result in the higher altitudes being more fuel efficient. I'll have to try that another day.
************************************************************************************************************** ***********
altitude: fuel remaining at target/fuel remaining at base arrival
10,000: 280/75 -- 250/60 -- 260/65
15,000: 290/90 -- 250/85 -- 275/100
20,000: 325/140 -- 275/110 -- 250/100
25,000: 300/150 -- 325/150 -- 305/150
25,000* 325/175 -- 310/160 -- 300/150
30,000: 300/145 -- 300/140 -- 295/140
Post edited April 06, 2017 by Masterius2017
