33k in the air
Staff Sergeant
- 1,347
- Jan 31, 2021
Indeed! Now let's get back to more weighty matters, such as Gremlins!
Just don't fly at 88 MPH or else . . . things happen. Lt. McFly can tell you more.
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I'm so glad it is just an academic discussion.
Amazing! I bet you can also find "Flux Capacitor" in there as well!
Maybe we can get to 25,000' on 20 gallons!Just don't fly at 88 MPH or else . . . things happen. Lt. McFly can tell you more.
The contents of an urchin shaped cod piece gets me to 25,000ft.Maybe we can get to 25,000' on 20 gallons!
Maybe we can get to 25,000' on 20 gallons!
After combat, can you land and put the tank back on, to keep your combat radius? I am thinking outside of the box here.
Just don't removed the gearbox armorYou could always link up with a KB-50 and top off to get home. I mean, if we can time-machine P-39 models, certainly we can time-machine aerial refuellers. Maybe remove the cannon in the spinner and replace it with plumbing to get the groundhog home?
Just don't removed the gearbox armor
The question was could it escort bombers in Europe. I have proven that many times by using information from the pilot's manual.
Groundhog mystical incantationsWhat else will protect the plumbing?!
Get real, brotha!
As another contributor asked way back, I wanna know why it wasn't used as such. What could you have possibly found that the 8th AF didn't in 1943?
For one thing, those dumbasses didn't have the Interwebz.
Problem is, the KB-50 cruises at about 245 miles an hour.You could always link up with a KB-50 and top off to get home. I mean, if we can time-machine P-39 models, certainly we can time-machine aerial refuellers. Maybe remove the cannon in the spinner and replace it with plumbing to get the groundhog home?
The "expert" doesn't seem to grasp that the drop tank is immaterial.
Hang a 110 gallon tank on the P-39 and you might wind up in place you can't get home from.
You are down 10-15 gallons of internal fuel after warm up, take off and climb to safe height to switch tanks.
Now what is critical is how much fuel is remaining in the the internal tanks after 15-20 minutes of combat and allowing for a 30 minute reserve.
That is the fuel available for egress from the combat area.
what was in the drop tank is smoke and mirrors.
Give him the 120 gallon fuel capacity, he is down to 105-110 when the tank (of whatever size ) is punched off. The P-39 with a tank attached is just a target for the Luftwaffe fighters.
30 minute reserve to get home is around 15 gallons. Down to 90-95 gallons.
Now the much debated combat allowance.
If the P-39s can defend the bombers by flying straight and level for 20 minutes they just might squeak out just over 30 gallons of fuel used in "combat".
If they have to do anything else, like turn, then the bets are off and the P-39s will not be able to stay at 25,000ft. The lower it goes the more fuel per minute it burns.
Unfortunately some of the P-39 charts are sheer nonsense. Both the take-off an climb charts and the range charts.
However the P-39 and other aircraft "fight operation instruction chart/s" do have a phrase/sentence that the "expert" has completely over looked.
In the box near the top that says "instructions for using chart" when you get to the notes, note "A" says...
"AVOID CONTINOUS CRUISING IN COLUMN 1 EXCEPT IN EMERGENCY"
The "expert's" entire flight plan except for landing is based around continuous cruise in Column 1 conditions.
Why not????Maybe we can get to 25,000' on 20 gallons!
You went to a whole lot of trouble to quote combat radius on 87gal internal and a 75gal drop tank. All P-39s would hold 120gal internal and carry a 110gal drop tank, same as what was at the fighter bases in east England.
And don't climb to 25000' at combat setting (careful, Flyboy doesn't know what that means, he can't find it quoted anywhere), use the ferry setting so that it takes you 31min and you don't burn up your engine. And you will have traveled 110mi (170IAS average = 220mphTAS). But don't figure that into your range because you may not be heading to your target.
Learn how to use the Flight Operation Instruction Chart (range chart). It doesn't include any figures from the Takeoff, Climb and Landing chart. Total fuel 230gal, less takeoff and climb reserve 20gal, 20min combat at 25000' 25gal, and 20min landing reserve 10gal leaving 175gal. Divide that by 62GPH = 2.8hrs flying time x 267mphTAS = 748mi. Divide by 2 for radius 374mi. Warmup and takeoff on internal, switch to drop tank as soon as gear/flaps are up and climb speed is reached. Simple form up as lead pair take a wide turn to target vector and the 7 following pairs make progressively narrower turns to form up the 16 plane squadron and vector to target. Cruise starts even before the 20gal T/O/Climb allowance has gotten you to 5000' as your climb to 25000' is on target heading. Drop tank fuel 90gal (110gal less 20gal T/O reserve) gets 387mi (90 divided by 62gph = 1.45hrs x 267mph). When the drop tank runs dry switch to internal and start home. If combat occurs and the drop tank is dropped before it is empty then combat radius will be shorter, just like any fighter carrying a drop tank. If combat occurs just as the drop tank runs dry then deduct combat allowance 25gal and landing reserve 10gal from the 120gal internal fuel (85gal left) and come home at 330TAS (85 divided by 62GPH = 1.4HR x 330mphTAS = 452mi).
Learn how to use the correct chart, it's much easier to use and more accurate.
And in most cases not flying over 5000'The "expert's" entire flight plan except for landing is based around continuous cruise in Column 1 conditions.
That's better than the 160 HP C172 with an O-320 that I fly!Why not????
we have a P-39N chart that "says" it can go from 5,000ft to 25,000ft at 8,000lbs in 24.9 minutes using 2300rpm and 32 in MAP while only using 4.4 gallons of fuel
And in most cases not flying over 5000'
Exactly!I think he very much plans to fly at 25,000ft, he just doesn't explain how his planes get there
I think we both know by now that there are errors in those charts, this was mentioned several times during this ordeal but there is some data that is somewhat useable. What is interesting to compare some of the chart information against the performance tests at P-39 Performance Tests, but I think you have mentioned this pages ago.His whole premise seems to be built around the speed in the chart the P-39 (without drop tank) can fly while the engine gasps for air at 25,000ft.
If he drops to 20,000ft the plane is slower and burns more fuel per hour and at 15,000ft the plane is slower yet while burning 66% more fuel per hour than 25,000ft.