Proof: F-35 can out-accelerate Su-27/35 in subsonic region
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gta4 wrote:This is because Su-27 will lose lift rapidly once it exceeds 24deg. Its lift drops much faster than eastern jets.
Any particular reason ? vortex separated from wing ?
gta4 wrote:By the way, according to F-16 test report by GD (the literature I recommended), F-16 could easily achieve a Cl of 1.7 at 24deg AOA, Mach 0.9. At lower subsonic speed I believe it could achieve it earlier.
I cant seem to be able to locate the literature
Can you post the link instead ?
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garrya wrote:gta4 wrote:This is because Su-27 will lose lift rapidly once it exceeds 24deg. Its lift drops much faster than eastern jets.
Any particular reason ? vortex separated from wing ?gta4 wrote:By the way, according to F-16 test report by GD (the literature I recommended), F-16 could easily achieve a Cl of 1.7 at 24deg AOA, Mach 0.9. At lower subsonic speed I believe it could achieve it earlier.
I cant seem to be able to locate the literature
Can you post the link instead ?
I will upload one tonight.
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So, are we agreed on these things?
1) Su-27's performance was calculated based off 18920-19000kg flying weight
2) Now Su-27 is much heavier. Fuel weight mush be sacrificed to meet the 18920kg flying weight standard
3) F-15 has a maximum Cl of 1.6 and has a better Cl/wing loading ratio
4) With the fuel for same AB duration, F-15 has better instantaneous turn, sustained turn, climbing rate and acceleration.
1) Su-27's performance was calculated based off 18920-19000kg flying weight
2) Now Su-27 is much heavier. Fuel weight mush be sacrificed to meet the 18920kg flying weight standard
3) F-15 has a maximum Cl of 1.6 and has a better Cl/wing loading ratio
4) With the fuel for same AB duration, F-15 has better instantaneous turn, sustained turn, climbing rate and acceleration.
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OK back to the main thread, the acceleration. Obviously the F-35 is not good at transonic acceleration like a F-16, but the majority of dogfight takes place at subsonic, so the acceleration at lower speed is more relevant. It determines how you regain energy after each maneuver and how frequently you can execute each maneuver, like a "cool down" time.
gta4 wrote:Obviously the F-35 is not good at transonic acceleration like a F-16, but the majority of dogfight takes place at subsonic, so the acceleration at lower speed is more relevant. It determines how you regain energy after each maneuver and how frequently you can execute each maneuver, like a "cool down" time.
Stooopid question: WHY is it obvious "not good acceleration like a F-16?"
Obvious because your numbers say so? Where again, do you get your numbers? Flight test data? Wind tunnel data? CFD results? Speculative numbers drawn from first-order, empirical studies with inputs gleaned from non-F-35 test reports / other aircraft?
I am not trying to slam you, just trying to understand "obvious" and "not good at transonic acceleration."
I am having difficulty reconciling your statement(s) with quotes from LM / BAE / Military pilots who swoon over the power of the motor, and compare F-35 acceleration to a clean F-16 (Beesley) and an otherwise clean F-16 with one centerline tank (which Gums says doesn't affect the F-16 much). I have also read statements / quotes here on F-16.net from program personnel stating the transonic acceleration is quite good and it goes through the Mach very easily. Granted, this last statement / assertion does not include a comparison to the Viper.
Take an F-16, stir in A-7, dollop of F-117, gob of F-22, dash of F/A-18, sprinkle with AV-8B, stir well + bake. Whaddya get? F-35.
garrya wrote:F-16 acceleration chart directly from flight manual
OK. Do you have the same page from the F-35 flight manual?
If not, from where are you getting numbers for the F-35 acceleration? (I've been following this thread... but don't recall any times for accel V1 to V2 at 30,000 ft. OR are we using the same first order analysis that was used in comparing the F-35 to the SU-35?) If so, I apologize and will have to sacrifice some more brain cells and go back and re-read.)
Take an F-16, stir in A-7, dollop of F-117, gob of F-22, dash of F/A-18, sprinkle with AV-8B, stir well + bake. Whaddya get? F-35.
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I think it has to do with the change to the F-35's KPP (Key Performance Parameter) on transonic acceleration. You can read more about it here:
http://elementsofpower.blogspot.com/201 ... sonic.html
http://elementsofpower.blogspot.com/201 ... sonic.html
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I now know it was silly of me to open the thread again, come on guys, take it back to keypub. clean f-16s vs loaded f-35.
you have the flight manuals, put the pods EW ect on, along with tanks and similar weapon load. They show what you think transonic acceleration is.
you have the flight manuals, put the pods EW ect on, along with tanks and similar weapon load. They show what you think transonic acceleration is.
Europe's fighters been decided. Not a Eurocanard, it's the F-35 (or insert derogatory term) Count the European countries with it.
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optimist wrote:I now know it was silly of me to open the thread again, come on guys, take it back to keypub. clean f-16s vs loaded f-35.
you have the flight manuals, put the pods EW ect on, along with tanks and similar weapon load. They show what you think transonic acceleration is.
there are drag index value in the table optimist, or you can add individual values as you like
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steve2267 wrote:gta4 wrote:Obviously the F-35 is not good at transonic acceleration like a F-16, but the majority of dogfight takes place at subsonic, so the acceleration at lower speed is more relevant. It determines how you regain energy after each maneuver and how frequently you can execute each maneuver, like a "cool down" time.
Stooopid question: WHY is it obvious "not good acceleration like a F-16?"
Obvious because your numbers say so? Where again, do you get your numbers? Flight test data? Wind tunnel data? CFD results? Speculative numbers drawn from first-order, empirical studies with inputs gleaned from non-F-35 test reports / other aircraft?
I am not trying to slam you, just trying to understand "obvious" and "not good at transonic acceleration."
I am having difficulty reconciling your statement(s) with quotes from LM / BAE / Military pilots who swoon over the power of the motor, and compare F-35 acceleration to a clean F-16 (Beesley) and an otherwise clean F-16 with one centerline tank (which Gums says doesn't affect the F-16 much). I have also read statements / quotes here on F-16.net from program personnel stating the transonic acceleration is quite good and it goes through the Mach very easily. Granted, this last statement / assertion does not include a comparison to the Viper.
QUOTE: the F-35 very nearly matches the performance of its' larger, more powerful cousin, the F-22 Raptor, Beesley explained. The "subsonic acceleration is about as good as a clean Block 50 F-16 or a Raptor- which is about as good as you can get." Beesley said.
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