garrya Posted January 7, 2016 Posted January 7, 2016 Another advantage of single engine fighter like F-16 is that they roll really fast , can be almost 2 time faster than F-15 and even superior than F-22 at low AoA
Hummingbird Posted January 7, 2016 Posted January 7, 2016 (edited) Iam aware that it is a clean chart , however both F-15 , F-14 are massive aircraft so i think it is unlikely that an aim-120 would really affected their performance We're not just talking about a single AIM-120 here though, we're talking about EIGHT missiles PLUS their accompanying pylons & adapters, all of which adds to the drag and weight of the aircraft and in the end has a very noticable effect on performance. Here's the F-15C with the same load out as the F-14B on the charts: As you can see there's a rather big difference between this and a completely clean F-15C. The exact figures for 10kft extracted from the chart: F-15C @ 41,000 lbs (66% fuel), w/ 4x AIM-7's + 4x AIM-9s @ 10,000 ft: Mach = G-load 0.2 = 1.0 0.3 = 1.8 0.4 = 2.6 0.5 = 3.4 0.6 = 4.3 0.7 = 5.25 0.75 = 5.7 And the F-14B/D for comparison: The exact figures for 10 kft extracted from the chart: F-14B/D @ 55,620 lbs (66% fuel) w/ 4x AIM-7's + 4x AIM-9's @ 10,000 ft: Mach = G-load 0.2 = 1.2 0.3 = 1.95 0.4 = 2.95 0.5 = 4.0 0.6 = 5.0 0.7 = 5.3 0.75 = 5.6 In other words with the same load out the F-14B/D enjoys an STR advantage over the F-15C from Mach 0.2 to 0.74, after which point the F-15C takes over, however it then reverses back into the F-14's favor again from Mach 1.1 onwards. In addition to this the F-14 is superior in ITR at all speeds. Another factor need to consider is logically speaking aircraft would have lauched a 2-4 missiles fromBVR before get into the merge ,it quite unlikely that aircraft get in dogfight with total amount of missiles they carried from start .For expample : i dont think F-14 would have dogfight with AIM-54 , AIM-7 is not that much better either This applies for both aircraft making it a rather moot point. I think the incident should be treated as the exception rather than the rule, there is also incident where F-15 turn 15G or Mig-25 turn 10G and pilot survive , but i think we can all agree that it not something that can always happen , if turning 9G make not much different to F-14 airframe then i think it is unlikely that they would have limited it down to only 6.5G , surely you can argue that they want airframe to last longer but F-16 , F-15 have 9G limit and they still working now even after F-14 retired About F-14 G limit here is something i can find There's no doubt that pulling 14 G's was an exceptional event, and it was far far from the norm, both because of the very real danger of structural failure, but also because it would result in a rather grumpy ground crew if said stunt was pulled in any other circumstance than a life or death dogfight. In the latter case however all G restrictions go right out the window and the pilot will simply do what he has to do to survive. Which is what iam really confuse and skeptical about , because at 10K feet the max sustain turn rate of the 2 aircraft isnt much better than 6G ( within the structure limit of F-14 ) and F-16 already have quite significant advantage at mach 0.85 , so by logic at sea level till 5000 feet where F-16 can turn 9G ( much higher than F-14 structure limit ) it would totally dominate F-14 at mach 0.75-0.85 range I've got the charts for both aircraft for alts of 5,000 - 10,000 - 15,000 - 25,000 - 35,000 feet, and the difference stays exactly the same at all these altitudes; i.e. the F-14 is superior in STR below Mach 0.65 and the F-16 is superior above that. Again though the F-14 enjoys an advantage in ITR across the entire speed & altitude range. And i think i did read somewhere that F-14 pilot say F-16 is a monster at sea level ( not sure that an F-14A or D though ) A clean F-16 is a monster at any altitude, and as mentioned the Navy F-14's used to train against completely clean F-16N's, which was a lightened up and boosted version of a regular F-16 - probably he hottest fighter ever in US service. Edited January 7, 2016 by Hummingbird
Hummingbird Posted January 7, 2016 Posted January 7, 2016 Another advantage of single engine fighter like F-16 is that they roll really fast , can be almost 2 time faster than F-15 and even superior than F-22 at low AoA Yes, the F-16 & F-15 both have a roll rate advantage, esp. once the F-14 folds out its wings. However the F-14's roll rate is already so high that anything higher won't prove too beneficial in a dogfight.
garrya Posted January 7, 2016 Posted January 7, 2016 (edited) We're not just talking about a single AIM-120 here though, we're talking about EIGHT missiles PLUS their accompanying pylons & adapters, all of which adds to the drag and weight of the aircraft and in the end has a very noticable effect on performance. still affected F-14, F-15 much less than it does to F-16 , and I think it is reasonable to assume that they atleast launched a few missiles from BVR Here's the F-15C with the same load out as the F-14B on the charts: As you can see there's a rather big difference between this and a completely clean F-15C. The exact figures for 10kft extracted from the chart: F-15C @ 41,000 lbs (66% fuel), w/ 4x AIM-7's + 4x AIM-9s @ 10,000 ft: Mach = G-load 0.2 = 1.0 0.3 = 1.8 0.4 = 2.6 0.5 = 3.4 0.6 = 4.3 0.7 = 5.25 0.75 = 5.7 And the F-14B/D for comparison: The exact figures for 10 kft extracted from the chart: F-14B/D @ 55,620 lbs (66% fuel) w/ 4x AIM-7's + 4x AIM-9's @ 10,000 ft: Mach = G-load 0.2 = 1.2 0.3 = 1.95 0.4 = 2.95 0.5 = 4.0 0.6 = 5.0 0.7 = 5.3 0.75 = 5.6 In other words with the same load out the F-14B/D enjoys an STR advantage over the F-15C from Mach 0.2 to 0.74, after which point the F-15C takes over, however it then reverses back into the F-14's favor again from Mach 1.1 onwards. . hummid bird you do it the wrong way , you compare the sustain turn rate of F-15 when f-15 isn't in it's corner speed with the sustain turn rate of F-14 when f-14 is in it's corner speed , that give an unfair advantage to F-14 the right way to do it is compare their maximum STR at their respective corner speed from the chart bellow F-14 corner speed is mach 0.55 , F-15 corner speed is mach 0.85 similar to F-16 http://i.imgur.com/uTsk7ra.jpg http://i.imgur.com/VKK60YS.png However it is important to note that in our earlier comparison the F-16 with DI 50 managed to get the same max STR with F-14D although even a clean F-16 with 50% fuel cannot sustain more than 7G at 10K feet , now the F-15 in our comparison can sustain 7.5G at 10K feet , what does that say ? , it mean the F-15 will have better max sustain turn rate than both F-14D and F-16 at 10K feet In addition to this the F-14 is superior in ITR at all speeds as far as I know at high speed F-15 will turn better than F-16 , and F-16 easily out turn F-14 at around mach 0.8 -0.85 ) , so this is actually very unlikely This applies for both aircraft making it a rather moot point. Actually no eventhough heavier load affected aircraft , they don't effected all aircraft the same way 4 GBU-12 on F-16 will affected it a lot more than on a F-14 or F-15 and so on , it have to do with their relative size and wetted area There's no doubt that pulling 14 G's was an exceptional event, and it was far far from the norm, both because of the very real danger of structural failure, but also because it would result in a rather grumpy ground crew if said stunt was pulled in any other circumstance than a life or death dogfight. In the latter case however all G restrictions go right out the window and the pilot will simply do what he has to do to survive which could be a problem because it can lead to structure failure of the aircraft , hence the G limit are in manual I've got the charts for both aircraft for alts of 5,000 - 10,000 - 15,000 - 25,000 - 35,000 feet, and the difference stays exactly the same at all these altitudes; Can you post the chart for F-14 at 5000 feet or sea level ? I already have F-16 chart i.e. the F-14 is superior in STR below Mach 0.65 and the F-16 is superior above that. what important is their max sustain turn rate at their corner speed for example at 10k feet : F-14 have superior STR at mach 0.55 , F-16 have superior STR at mach 0.85 however they both have the same max sustain turn rate of 14-15 degrees/second my point is that even though at sea level or 5000 feet F-14 still good at low speed , F-16 still good at high speed , the max sustain turn rate of F-16 will be much better than F-14 Again though the F-14 enjoys an advantage in ITR across the entire speed & altitude range. I don't think F-14 enjoy advantage of ITR across the entire speed and envelop for example from the chart bellow http://i.imgur.com/VKK60YS.png http://i.imgur.com/hlpncUr.png at mach 0.85 the ITR of F-14 is merely 11 degree/ seconds while the ITR of F-16 is 19 degrees/second which mean F-16 turn almost 2 times faster A clean F-16 is a monster at any altitude, and as mentioned the Navy F-14's used to train against completely clean F-16N's, which was a lightened up and boosted version of a regular F-16 - probably he hottest fighter ever in US service. F-16N based on the early-production small-inlet Block 30 F-16C/D airframe hence it cannot provide enough air flow for the F-110 engine result in less thrust than latter F-16 that have big mouth inlet and actually F-16 even in clean configuration is still a slug at high altitude compare to F-15 http://www.f-16.net/f-16_versions_article22.html Edited January 7, 2016 by garrya
garrya Posted January 7, 2016 Posted January 7, 2016 Yes, the F-16 & F-15 both have a roll rate advantage, esp. once the F-14 folds out its wings. However the F-14's roll rate is already so high that anything higher won't prove too beneficial in a dogfight. I think roll rate is very importance in dogfight , it help you change direction and jink enemy
Hummingbird Posted January 8, 2016 Posted January 8, 2016 (edited) hummid bird you do it the wrong way , you compare the sustain turn rate of F-15 when f-15 isn't in it's corner speed with the sustain turn rate of F-14 when f-14 is in it's corner speed , that give an unfair advantage to F-14 the right way to do it is compare their maximum STR at their respective corner speed from the chart bellow F-14 corner speed is mach 0.55 , F-15 corner speed is mach 0.85 similar to F-16 http://i.imgur.com/uTsk7ra.jpg http://i.imgur.com/VKK60YS.png No I am not doing it the wrong way, please read what I write before responding, I specifically wrote: "with the same load out the F-14B/D enjoys an STR advantage over the F-15C from Mach 0.2 to 0.74, after which point the F-15C takes over, however it then reverses back into the F-14's favor again from Mach 1.1 onwards" However it is important to note that in our earlier comparison the F-16 with DI 50 managed to get the same max STR with F-14D although even a clean F-16 with 50% fuel cannot sustain more than 7G at 10K feet , now the F-15 in our comparison can sustain 7.5G at 10K feet , what does that say ? , it mean the F-15 will have better max sustain turn rate than both F-14D and F-16 at 10K feet You are overlooking the importance of G vs speed, the F-15C max STLF might be 7.5 G @ Mach 0.86 but its max STR is exactly 14 deg/sec, in other words just below the 14.2 deg/sec of the F-14B/D and F-16C and at a much higher speed and therefire radius: In short the F-14 & 16 would have little trouble cutting inside the F-15's circle and gunning it down if it chooses to stay in the horizontal. The F-15 needs to go vertical when fighting the F-14 or F-16. as far as I know at high speed F-15 will turn better than F-16 , and F-16 easily out turn F-14 at around mach 0.8 -0.85 ) , so this is actually very unlikely ITR is all about lift to weight and the F-14 has that over the F-16 and esp. the F-15, so it is not unlikely, it is fact and its on the charts as well. The lift line doesn't just suddenly stop, it continues along the same path until the ultimate load limit of the aircraft, which for all three aircraft is 12+ G's. Actually no eventhough heavier load affected aircraft , they don't effected all aircraft the same way 4 GBU-12 on F-16 will affected it a lot more than on a F-14 or F-15 and so on , it have to do with their relative size and wetted area The F-14 is the biggest of the three, so where does that leave you? ;) which could be a problem because it can lead to structure failure of the aircraft , hence the G limit are in manual Again, the structural failure point of the F-14 is exactly the same as that of the F-15 (read ultimate load limit) =. 12+ G's. The reason the F-14 has a load limit of 7 to 6.5 G's is for airframe longevity reasons: F-14 orders were cut short and no new airframes were manufactured, which meant each airframe had to last a lot longer than usual, thus the Navy imposed a 7 and later 6.5 G load limit. - I wonder how many times I'll have to repeat this? This however doesn't change the fact that the F-14 could at any point during the speed envelope pull a higher ITR than either the F-15 or F-16. what important is their max sustain turn rate at their corner speed for example at 10k feet : F-14 have superior STR at mach 0.55 , F-16 have superior STR at mach 0.85 however they both have the same max sustain turn rate of 14-15 degrees/second my point is that even though at sea level or 5000 feet F-14 still good at low speed , F-16 still good at high speed , the max sustain turn rate of F-16 will be much better than F-14 Nope, at SL or 5,000 ft their max STR is again the same, the relationship does not change from 10,000 ft to SL and vice versa. I don't think F-14 enjoy advantage of ITR across the entire speed and envelop for example from the chart bellow http://i.imgur.com/VKK60YS.png http://i.imgur.com/hlpncUr.png at mach 0.85 the ITR of F-14 is merely 11 degree/ seconds while the ITR of F-16 is 19 degrees/second which mean F-16 turn almost 2 times faster If you want to unfairly limit the F-14 to 6.5 G's (no F-14 pilot would limit himself to this in a life or death dogfight) then it is 12.5 deg/sec at Mach 0.85 (not 11), but if you want to be fair and give it the same 9 G limit as the F-16, which the F-14 airframe can easily take, then it's over 24 deg/sec at Mach 0.85. In other words at Mach 0.85 the F-14 pilot can at any point pull over 5 deg/sec more than the F-16. Simply follow the lift line to Mach 0.55 @ 6.5 G and continue it on the same path from there to Mach 0.85 @ 9 G. Remember the F-14 features no G limiter, the pilot can pull as many G's as he desires, and 9 G's is a piece of cake for the F-14 airframe which has the same ultimate load limit as the F-15 = 12+ G's. The 7 and later 6.5 G load limit imposed on the F-14 by the Navy was for longevity reasons as the F-14 airframes had to last a lot longer than F-15 or F-16's whilst constantly being subject to the high stresses of carrier landings. F-16N based on the early-production small-inlet Block 30 F-16C/D airframe hence it cannot provide enough air flow for the F-110 engine result in less thrust than latter F-16 that have big mouth inlet and actually F-16 even in clean configuration is still a slug at high altitude compare to F-15 http://www.f-16.net/f-16_versions_article22.html The small inlet resulted in a 2,000 lbf loss in thrust for the F110-GE-100 engine, so the thrust was still higher than on a regular F-16 with its GE-129, and the F-16N was considerably lighter as well, all of which led to a higher ITR & STR at all speeds. There's a reason the F-16N is considered the hottest bird to have served in the aggressor role. Edited January 8, 2016 by Hummingbird
mvsgas Posted January 8, 2016 Posted January 8, 2016 (edited) The small inlet resulted in a 2,000 lbf loss in thrust for the F110-GE-100 engine, so the thrust was still higher than on a regular F-16 with its GE-129, and the F-16N was considerably lighter as well, all of which led to a higher ITR & STR at all speeds. There's a reason the F-16N is considered the hottest bird to have served in the aggressor role. Two different engines, GE-100 has less thrust that GE-129, no matter the intake. GE-129 only used on block 50. GE-100 was used on blocks 30 (F-16N), 40. How much lighter? Edited January 8, 2016 by mvsgas To whom it may concern, I am an idiot, unfortunately for the world, I have a internet connection and a fondness for beer....apologies for that. Thank you for you patience. Many people don't want the truth, they want constant reassurance that whatever misconception/fallacies they believe in are true..
Hummingbird Posted January 8, 2016 Posted January 8, 2016 (edited) Here's the F-14B/D's max STR at different altitudes: Sea level = 18.2 deg/sec @ Mach 0.52 5,000 ft = 16.1 deg/sec @ Mach 0.57 10,000 ft = 14.2 deg/sec @ Mach 0.61 15,000 ft = 12.2 deg/sec @ Mach 0.68 25,000 ft = 8.5 deg/sec @ Mach 0.73 35,000 ft = 5.2 deg/sec @ Mach 0.76 Edited January 8, 2016 by Hummingbird
Hummingbird Posted January 8, 2016 Posted January 8, 2016 Two different engines, GE-100 has less thrust that GE-129, no matter the intake. GE-129 only used on block 50. GE-100 was used on blocks 30 (F-16N), 40. Why was the F-16N lighter? How much lighter? As far as I can understand the thrust of the F-16N's engines was 29,000 lbf std., reduced to 27,000 lbf installed. The F-16N was lighter because it carried no gun, it was basically a F-16A without a gun and a more powerful engine.
mvsgas Posted January 8, 2016 Posted January 8, 2016 (edited) Well it had the bigger tail and wing of the C ( not by much AFAIK) and all block 30 have that same advantage ( minus the gun weight). Refer to Figure 1-19. The aircraft is powered by a single F110–GE-100 afterburning turbofan engine. Maximum thrust is approximately 25,000 pounds (small inlet) or 28,000 pounds (big inlet). 1F-16CM-1 page 1-64 (Aug 2009, with S-4 and 5) P.S. never mind, I think they had same wing size Edited January 8, 2016 by mvsgas To whom it may concern, I am an idiot, unfortunately for the world, I have a internet connection and a fondness for beer....apologies for that. Thank you for you patience. Many people don't want the truth, they want constant reassurance that whatever misconception/fallacies they believe in are true..
Hummingbird Posted January 8, 2016 Posted January 8, 2016 Well it had the bigger tail and wing of the C ( not by much AFAIK) and all block 30 have that same advantage ( minus the gun weight). The F-16N were operated completely clean though, and as mentioned without the gun or ASPJ. I believe they weighed no more than 17,000 lbs ready to go. According to the aggressor squadrons they never had a more agile aircraft.
mvsgas Posted January 8, 2016 Posted January 8, 2016 The F-16N were operated completely clean though, and as mentioned without the gun or ASPJ. I believe they weighed no more than 17,000 lbs ready to go. According to the aggressor squadrons they never had a more agile aircraft. :D So not representing actual operational F-16 performance? To whom it may concern, I am an idiot, unfortunately for the world, I have a internet connection and a fondness for beer....apologies for that. Thank you for you patience. Many people don't want the truth, they want constant reassurance that whatever misconception/fallacies they believe in are true..
Hummingbird Posted January 8, 2016 Posted January 8, 2016 :D So not representing actual operational F-16 performance? Exactly :D
mvsgas Posted January 8, 2016 Posted January 8, 2016 How about other aircraft used on similar exercises as aggressors? Like F-5, F-21, current F-16, etc. Would it be save to assume they are modified as well and not representing operational aircraft? To whom it may concern, I am an idiot, unfortunately for the world, I have a internet connection and a fondness for beer....apologies for that. Thank you for you patience. Many people don't want the truth, they want constant reassurance that whatever misconception/fallacies they believe in are true..
Hummingbird Posted January 8, 2016 Posted January 8, 2016 How about other aircraft used on similar exercises as aggressors? Like F-5, F-21, current F-16, etc. Would it be save to assume they are modified as well and not representing operational aircraft? I don't know wether they carried guns, but IIRC the current F-16C aggressors do.
mvsgas Posted January 8, 2016 Posted January 8, 2016 (edited) So current F-16 aggressors (Block 30 in Eielson AFB, blocks 25, 32 and 42 in Nellis and block 15 in Fallon) are closer to operational aircraft ( keeping in mind the different equipment, like extra antennas, ect.). I wonder if the F-5, F-15 or other aircraft used in exercise of this type are modified. Edited January 8, 2016 by mvsgas To whom it may concern, I am an idiot, unfortunately for the world, I have a internet connection and a fondness for beer....apologies for that. Thank you for you patience. Many people don't want the truth, they want constant reassurance that whatever misconception/fallacies they believe in are true..
mvsgas Posted January 8, 2016 Posted January 8, 2016 Another thing I am ( and many of us are) guilty of doing is using HUD video/photos to say: "Aircraft X had Y on its sights so it smoke it". But without context we really do not know. If we where to see HUD video of demos in airshows like these, could we tell they where demos in air shows or practice for them? c-UHWJf0Gk0 f4pa2Acke-o To whom it may concern, I am an idiot, unfortunately for the world, I have a internet connection and a fondness for beer....apologies for that. Thank you for you patience. Many people don't want the truth, they want constant reassurance that whatever misconception/fallacies they believe in are true..
Hummingbird Posted January 8, 2016 Posted January 8, 2016 Pretty certain they wouldn't be recording HUD footage with pippers in an airshow, also Airshows take place close to sea level so the crowd can see the action where'as actual mock fights usually take place at 10,000 ft and higher.
Basher54321 Posted January 8, 2016 Posted January 8, 2016 Remember the F-14 features no G limiter, the pilot can pull as many G's as he desires, and 9 G's is a piece of cake for the F-14 airframe which has the same ultimate load limit as the F-15 = 12+ G's. The 7 and later 6.5 G load limit imposed on the F-14 by the Navy was for longevity reasons as the F-14 airframes had to last a lot longer than F-15 or F-16's whilst constantly being subject to the high stresses of carrier landings. If the F-14 was designed as a 9G sustained airframe then that margin doesn't seem to far off (F-16 is around 14G airframe limit). I would say though the issue is more down to the pilot, 9 positive Gs sustained was certainly the high end limit with the older G suits and the pilot has to train and condition to that - so e.g if a pilot has spent most of his flying life only sustaining 6.5Gs then suddenly sustaining 9Gs for any useful period of time doesn't seem realistic considering what is actually involved. In combat accounts many jets have pulled 12+ Gs in panicked situations (avoiding the ground etc ) the pilot might get away with a few seconds before blacking out (some did). I don't think this an area anyone would go to intentionally because pulling Gs within in your limit and not blacking out is better.
Basher54321 Posted January 8, 2016 Posted January 8, 2016 Not unique, it just boils down to the USN did not want or could spend the money to fix it. This at the time all other aggressor units where closing, right? It makes sense. At any rate, we still talking about Red flag and similar exercises being indicative or not of aircraft performance? Or didn't want to spend money preventing it :) I can find out but are you aware of any other F-16 types that skipped initial structural testing for a mod like this? Previous post above was actually back OT - fancy that :)
Basher54321 Posted January 8, 2016 Posted January 8, 2016 Another thing I am ( and many of us are) guilty of doing is using HUD video/photos to say: "Aircraft X had Y on its sights so it smoke it". But without context we really do not know. Yes very good point - surprising how little they really show.
Hummingbird Posted January 8, 2016 Posted January 8, 2016 (edited) If the F-14 was designed as a 9G sustained airframe then that margin doesn't seem to far off (F-16 is around 14G airframe limit). The F-14 airframe is very strong, esp. the wing assembly which is exceptionally strong. Infact stress testing by Grumman revealed that panels would start flying off before the wings would fail. Grumman flight tested the F-14 to 13 G's without issues, with 'in the shop' stress testing going beyond this. I would say though the issue is more down to the pilot, 9 positive Gs sustained was certainly the high end limit with the older G suits and the pilot has to train and condition to that - so e.g if a pilot has spent most of his flying life only sustaining 6.5Gs then suddenly sustaining 9Gs for any useful period of time doesn't seem realistic considering what is actually involved. In combat accounts many jets have pulled 12+ Gs in panicked situations (avoiding the ground etc ) the pilot might get away with a few seconds before blacking out (some did). I don't think this an area anyone would go to intentionally because pulling Gs within in your limit and not blacking out is better. We must assume similar G suits are available to the pilots in all three aircraft, they were after all in service together for several decades. As for pilot G tolerance, whilst I agree that pilots who regularly train at sustaining 9 G's will have an advantage over those who usually only go to 7 G's, if we start using them as the benchmark then we will be moving away from the actual capabilites of the aircraft. We have to keep in mind that had F-14 orders not been cut short and had production been allowed to continue, well then the Navy wouldn't have restricted the F-14 to a 7 and later 6.5 G load limit either, it then almost certainly would've been operationally cleared for 8.5 to 9 G's. Edited January 8, 2016 by Hummingbird
Basher54321 Posted January 8, 2016 Posted January 8, 2016 We must assume similar G suits are available to the pilots in all three aircraft, they were after all in service together for several decades. As for pilot G tolerance, whilst I agree that pilots who regularly train at sustaining 9 G's will have an advantage over those who usually only go to 7 G's, if we start using them as the benchmark then we will be moving away from the actual capabilites of the aircraft. What I mean by older suits is that newer suits like Combat Edge are potentially better and allow pilots to get to 9G easier than previously. Probably the wrong route to take - you can have all kinds of what ifs. If talking about aircraft performance and capability - surely in Red Flag today performance of aircraft sensors, information management and how they work with other Blue assets is more important IMO :thumbup:
garrya Posted January 8, 2016 Posted January 8, 2016 (edited) No I am not doing it the wrong way, please read what I write before responding, I specifically wrote: "with the same load out the F-14B/D enjoys an STR advantage over the F-15C from Mach 0.2 to 0.74, after which point the F-15C takes over, however it then reverses back into the F-14's favor again from Mach 1.1 onwards" I read what you wrote and my opinion is that it is irrelevant Because the F-15 would not fly at the F-14 corner speed so that itself turn slower , and the F-14 won't turn at F-15 corner speed either , hence the correct way would be to compare their respective Max sustainable turn rate You are overlooking the importance of G vs speed, the F-15C max STLF might be 7.5 G @ Mach 0.86 but its max STR is exactly 14 deg/sec, in other words just below the 14.2 deg/sec of the F-14B/D and F-16C and at a much higher speed and therefire radius: In short the F-14 & 16 would have little trouble cutting inside the F-15's circle and gunning it down if it chooses to stay in the horizontal.The F-15 needs to go vertical when fighting the F-14 or F-16. I don't underestimate the important of speed in turning Corner speed of F-16 at 10k feet and DI 50 is around mach 0.84-0.85 too and it's sustainable G is lower than F-15 almost 1G , there aren't no way F-15 Max sustainable turn rate is less than F-16 and F-14 in that situation Measure it if you want turn rate = [1091*tan(bank angle)] /[true air speed in knots] G-load is 1/cos( bank angle) ITR is all about lift to weight and the F-14 has that over the F-16 and esp. the F-15, so it is not unlikely, it is fact and its on the charts as well. The lift line doesn't just suddenly stop, it continues along the same path until the ultimate load limit of the aircraft, which for all three aircraft is 12+ G's. Wing loading of F-14 is around 468 kg/m2 that is higher than F-16 and much higher than F-15 Along with the fact that F-16 have LERX it will have better CL value at AoA compare to both F-14 and F-15 And you cannot just draw or connect an imagine max turn rate line , they are not liner , and aircraft don't turn at the same AoA at all speed , different wing configuratition lead to very different CL , Cd and stall AoA What F-14 have over F-15 and F-16 is that it can swing it's wing out at less sweep angle hence it turn very good at slow speed, but that won't happen at faster speed The F-14 is the biggest of the three, so where does that leave you? ;) That mean F-14 with heavy load will be affected less than F-16 and F-15 , but it also mean as the load get lighter the performance of f-14 doesn't change much while F-16 performance will improve significantly Which is why I think it is unrealistic for them to carry full load till dogfight and don't lauch a single missiles Again, the structural failure point of the F-14 is exactly the same as that of the F-15 (read ultimate load limit) =. 12+ G's. The reason the F-14 has a load limit of 7 to 6.5 G's is for airframe longevity reasons: F-14 orders were cut short and no new airframes were manufactured, which meant each airframe had to last a lot longer than usual, thus the Navy imposed a 7 and later 6.5 G load limit. - I wonder how many times I'll have to repeat this? Hummingbird , it doesn't matter if you repeat it , because it only your words and your guess is only as good as mine The problem is the flight manual limited F-14 to 6.5G as well and even F-14 pilot admited his aircraft is limited to 7.5G You have to see it from my point of view " why should I trust you more than the flight manual and pilot word " ? The F-15C is probably the premier BFM fighter and more capable in that area than the Tomcat. You have to remember, the F-15C has a 9G turning capability versus 6.5 to 7.0 G for the Tomcat. But the F-15C is strictly air-to-air, so there are trade-offs in capabilities between the two jets.They don't drop bombs, we do. Another thing: a lot of success in BFM has to do with the pilot's ability to maximize the jet's capability. Fortunately, the best trained guys who fly the F-15C are on our side! http://foxtrotalpha.jalopnik.com/an-...imp-1610043625 During validation of the existing NATOPS rolling G envelope, the primary F-14 test asset sustained extensive structural damage to the starboard engine weekly doors and aft fixed cowl when certain structural limits were exceeded. As it turned out, the problem was not due to DFCS but was related to a NATOP�s operational envelope which had not been previously verified. This resulted in the fleet-wide rolling G restrictions from NAVAIR. The impact to the program is going to be felt in an initial envelope for DFCS with reduced rolling g above and beyond the cutbacks for AFCS roll SAS-on, simply because the Navy cannot support any further structural testing until the F-14 test aircraft is repaired. Data is still being analyzed and the restrictions haven�t been fully defined yet, but it was anticipated that the initial envelope would still include 6.5 g�s symmetric throughout for gross weights of 49.5K or less. For the clean configuration: 4 g�s rolling to 570 KCAS, 3 g rolling to 700, and 1 g rolls/no abrupt stick inputs above 700/1.4 For external tanks or Pylon mounted AIM-54s: the "region 3" from NATOPS will begin above 570 KCAS/1.15 TMN at low alt, or 500 KCAS above 25K And yes I know there are case F-14 do something like 15G and still survive but it is the exception not the rules , there are case mig-25 turn more than 10G and still survive but that doesn't mean we will treat it as if Mig-25 can turn upward 10 G all the time This however doesn't change the fact that the F-14 could at any point during the speed envelope pull a higher ITR than either the F-15 or F-16. But it cannot do that , you cannot assume that because at one point in the envelope your aircraft have better ITR then at all points your aircraft have better ITR , For one aircraft doesn't turn at same AoA at all speed , secondly the Reynolds number is not gonna be the same across the envelope Nope, at SL or 5,000 ft their max STR is again the same, the relationship does not change from 10,000 ft to SL and vice versa. Just post the turn rate graph for F-14 at sea level or 5000K feet then we will see If you want to unfairly limit the F-14 to 6.5 G's (no F-14 pilot would limit himself to this in a life or death dogfight) then it is 12.5 deg/sec at Mach 0.85 (not 11), but if you want to be fair and give it the same 9 G limit as the F-16, which the F-14 airframe can easily take, Why would you think F-14 can easily take 9g while the manual andt say otherwise ? then it's over 24 deg/sec at Mach 0.85. In other words at Mach 0.85 the F-14 pilot can at any point pull over 5 deg/sec more than the F-16. Simply follow the lift line to Mach 0.55 @ 6.5 G and continue it on the same path from there to Mach 0.85 @ 9 G. Turn rate doesn't work like that as explained before Remember the F-14 features no G limiter, the pilot can pull as many G's as he desires, and 9 G's is a piece of cake for the F-14 airframe which has the same ultimate load limit as the F-15 = 12+ G's. The 7 and later 6.5 G load limit imposed on the F-14 by the Navy was for longevity reasons as the F-14 airframes had to last a lot longer than F-15 or F-16's whilst constantly being subject to the high stresses of carrier landings. Here the thing for you to consider , what if because F-14 have to constantly sustain stress when landing on carrier , that develop crack in airframe that break the aircraft if it turn too hard , hence the limit The small inlet resulted in a 2,000 lbf loss in thrust for the F110-GE-100 engine, so the thrust was still higher than on a regular F-16 with its GE-129, and the F-16N was considerably lighter as well, all of which led to a higher ITR & STR at all speeds. There's a reason the F-16N is considered the hottest bird to have served in the aggressor role. Where did you get the figure that small inlet reduce thrust by 2000 lbs ? F-110GE 129 produce 29500 pounds of thrust so there no way F-16N have more thrust than F-16 block 50/52 And what is the weight of F-16N ? Anyway F-16N is lighter so it will have better ITR but it doesn't necessarily have better STR because STR is factor of drag as well ,and while F-16 have exactly the same outer aerodynamic , it will have less thrust to fight again drag Edited January 8, 2016 by garrya
garrya Posted January 8, 2016 Posted January 8, 2016 Here's the F-14B/D's max STR at different altitudes: Sea level = 18.2 deg/sec @ Mach 0.52 5,000 ft = 16.1 deg/sec @ Mach 0.57 10,000 ft = 14.2 deg/sec @ Mach 0.61 15,000 ft = 12.2 deg/sec @ Mach 0.68 25,000 ft = 8.5 deg/sec @ Mach 0.73 35,000 ft = 5.2 deg/sec @ Mach 0.76 can you just post the actual chart of F-14 at sea level or 5k feet instead .?
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