

cheezit
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F-14A/B Flight Model Tuning - Guided Discussion
cheezit replied to IronMike's topic in DCS: F-14A & B
My source for the 82,000 MTOW for the A3D was, sadly, the plane's Wikipedia article, which in turn claims to source it from the 1988 publication "McDonnell Douglas Aircraft since 1920: Volume I", which I do not own a copy of to check. I see the same that you do looking at the 1967 SACs for the A3 variants (EA-3B, TA-3B, RA-3B, etc, but no KA-3B/EKA-3B) that the MTOW for a cat shot doesn't ever exceed 73,000 lbs and for land doesn't exceed 78,000 lbs - probably the 82,000 figure either is erroneous, or pertains only to the ~85 tanker/tanker+EW variants. -
F-14A/B Flight Model Tuning - Guided Discussion
cheezit replied to IronMike's topic in DCS: F-14A & B
Nearly everything you wrote here is wrong. Do you have any books handy on the F-14's design, or are you limited to internet sources for the time being? Ciminera's books would be useful in dispelling some of these notions, as would Cooper and Cooper/Bishop, for starters. You could also look at HUD film of the F-14D air show demo if you find written sources un-credible want visual confirmation that an F-14 can hit 9.5 or 10g without spontaneously disassembling or bending like a coke can. Incidentally, you did get one thing right - test pilots and Grumman did rate the F-14's effective G limits higher than fleet pilots (not to mention NATOPS) did! Whereas the fleet pilots contented themselves with some 12G yanks and subsequent maintenance inspections revealing "not a bolt out of place" (a quote from CPT Keith "Okie" Nance), test pilots and Grumman instead considered the airframe to be either "symmetrically unlimited" or pilot-limited for symmetric pulls, due to the mechanism Spurts mentioned wherein the lifting body effect (remember the tunnel was a designed airfoil, not just a flat surface) relieved the wings at high AoA. Of course, with an asymmetric pull you can over-G a Tomcat pretty easily, just as you can over-G a 9g-symmetric F-16 at 4g with an sufficiently asymmetric pull - generally the F-16 will yell at you before you get there, though! This sort of thing is part of why the Air Force developed and installed/integrated an overload warning system before increasing the F-15's G-limit from 7.33 to 9 symmetric as part of the mid-1980s MSIP process. -
F-14A/B Flight Model Tuning - Guided Discussion
cheezit replied to IronMike's topic in DCS: F-14A & B
The A3D was heavier (MTOW of 82,000 lb vs 74,000 and change as the final MTOW for the Tomcat), no? And of course the F-111Bs that had some cat shots and traps during carrier suitability testing were much heavier - fair game not to count those since the aircraft (thankfully) never served! -
How to accelerate to Mach 2? Is there a recommand method?
cheezit replied to YATEIFEI's topic in DCS: F-14A & B
Once you get the perf charts (NAVAIR 01-F14AAP-1.1), look at Figure 8-6 [Deck Launched Intercept] (page XI-8-24, XI-8-25, XI-8-26) for climb schedules that will put you at Mach 1.4 at 45k feet in various configurations. The schedule they will put you on will basically follow this 'route' (obviously the DLI chart will take the change in weight during the flight into account in a way that the following illustration doesn't): You may want to also play around with alternative routes, such as the obvious one sketched out here: ... although it won't be quite as straightforward to follow as the route in 8-6. And of course, the same thing can be played around with if you look at the perf charts for the A. -
Forgive the nitpick of one line of your otherwise very good post, but I don't think this is the case. Even if a magic wand had been waved and a hypothetical AIM-54E with a 200NM max range and 50NM no-escape zone had existed at the time the decisions were made to sunset both the Tomcat and the Phoenix, both still would have been toast. The S-3 wasn't replaced because the Navy found a better carrier-based sub hunter or tanker, the A-6 & KA-6D weren't replaced because the Navy found better all-weather attack jets or tankers, the EA-6B wasn't replaced because the Navy found a better standoff jammer, etc. As in these analogous scenarios, the -120 and its launch platforms would have been retained *and nothing else would have* regardless of whether they were better (either in the weaker sense of 'better overall' or the stronger sense of 'better in all scenarios/every regard'), because they were newer, cheaper both for initial costs and ongoing costs, and good enough for a world without 400 divisions champing at the bit to rush through the Fulda Gap. That the AMRAAM program office and Hughes/Raytheon managed to continue to iteratively improve the missile over the ensuing decades and bring it to a very high level of capability in a nice small package was lagniappe.
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For the 54A, sure. The 54C we have in-game, roughly representative of the ones from the TECHEVAL and OPEVAL circa 1984-1985, is early 80s purely digital computer tech, the most they could stuff at the time into a circuit board ~15 inches in diameter and < 150 lbs in weight. Substantially better than the IBM-compatible PC you might have bought at the time, though less powerful than the early UNIX-on-custom-chips workstations and VAX/PDP-whatever type minicomputers it would have been designed on. The 54C ECCM/Sealed, 54C+, and "54C++"(basically-but-not-exactly a combination of the prior two listed items) from the late 80s and early 90s, as well as regular 54Cs with the reprogrammable program- and data-nonvolatile memory having been reprogrammed in service (a capability the early AMRAAM didn't have, because space and cost and power constraints didn't allow Hughes (who developed the 54C and 120A simultaneously) to fit it in there) are of course not represented in-game; keep that in mind if you're trying to represent a scenario after about 1986. Although of course the QA problems from the mid-1980s production 54C are also not represented in-game, so maybe we count our blessings. Unless you want to say the Phoenixes that go to the moon or turn backwards represent units with bad solder joints between components and the PCB :V
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That's when it's fast and not super high - the F110 is like a stroker and the TF30 is more like a peaky high-strung thing that benefits more from the ram air effect*. Eg. at sea level, the F110 in full blower starts with about 23500 lbf installed at zero airspeed and gets up to 30500 lbf installed at mach 0.9, then tails off above that, whereas the TF30 starts out at about 17500 lbf installed at zero airspeed, peaks at the same 30500 lbf at mach 0.9, but doesn't tail off as quickly at higher speeds. The higher you go, the bigger the gap becomes at low airspeeds (the F110 has dramatically better static suction) until "above 25000 feet and below 250 kias, all the TF30 does at mil power is turn JP5 into noise" as another once said. *Unsure how much of this is the design of the engine itself (turbine compression stages and bypass and afterburner) versus the design of the variable ramp intakes and the tuning or lack thereof that the intake ramp schedule got for each engine, any intake ramp changes that happened down the line for maintainability and reliability, etc.
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If the most in-demand F-14D or F-14B(U) weren't the OIF/OIF II representative, DFCS wouldn't *need* to be a sticking point. Ditto modeling how the AIM-9X worked with the MIL-STD-1760-capable variants of the Tomcat.
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Thanks for your contribution! I would say that all kill claims and reports of exploits need to be scrutinized, whether they come from Iran, Israel, the USAF, USN, etc. Circumstances matter and are non-trivial to account for, everybody honestly thinks they've destroyed more aircraft than they actually did at all times (even without taking purposeful overclaiming into account), aircraft are frequently misidentified, etc.
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In your defense, sources about the AIM-54C's development/history that are broadly accessible are really muddled and don't generally agree with each other. If I could write a letter to somebody who was at the program office (Dave "Hey Joe" Parsons fits the bill and occasionally does interviews, but I'm not going to try to internet-detective his email address to harass him for answers) to clear up some questions raised by eg. the old Navy history of the missile.
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I think this is true for the Hornet and the Viper, but not the Eagle. The Eagle was probably 75% of the maintenance problem that the F-14A was (somewhat fewer hydraulic problems and many fewer electronics problems) - while the Air Force doesn't publish maintenance hours per flight hour numbers like the Navy and USMC do, it does publish costs per flight hour, and the Eagle is more expensive than other 4th gen jets by a mile; the exact numbers differ from annual report to annual report, but it's generally about 2x what the F-16 costs to run (circa $40k vs $20k/hour in recent years, with fuel costs making up only a small fraction of that difference). Even the projected target cost-per-flight-hour of the F-15EX (designed to be more maintainable) is still high compared to everything else 4th-gen that's still in the air, and that's a number coming from the manufacturer's sales & marketing department, not an observed figure. It's interesting to look at how the Air Force treated the F-15 versus how the Navy treated the F-14 in terms of upgrades over the common service life of both aircraft (roughly 1976-2006). Everybody knows about the boneheaded spares decision in the early 1980s (I had a copy of the appropriations hearing where that decision was made, but I can't find it now), but look at the original Grumman/Navy plan for F-14 development and it's similar to what the Air Force actually did with the F-15. Different program offices, budget priorities, etc. Nb. that there would be no F-15Cs in service in 2023 and no F-15EX if the original Raptor buy hadn't been repeatedly clipped until ending up at a quarter of what was originally intended. Similarly, there'd probably be no SuperHornet if the specific sequence of events in the early 90s hadn't played out about the way they did, with the A-6 upgrades being cancelled because the A-12 was in the works, then the A-12 being cancelled, then the F-117N proposals all being rejected, then the A-6 and S-3 in their entirety and the F-14 Block I Strike program and the AAAM program being killed for budget reasons after Desert Storm, then the F-14D buy being severely clipped because NATF was in the works, then NATF being cancelled, then the joint USMC/RN program to replace the Harrier becoming 'jointer' and then 'jointest' as it metastasized into the JSF program, then the legacy Hornet program executive office needing a few billion for the MLU and CBR programs, then finally SuperHornet winning over QuickStrike and all other "Super Tomcat" variants to be the stopgap until a 5th-gen flight deck was achieved - and there's plenty that I missed. At least we can say that the Superbug was a very good aircraft for the wars we actually ended up fighting during its service life. Further note that, despite both design improvements for enhanced maintainability and an extra two decades of experience maintaining the design, the F/A-18E/F has seen substantially worse availability than the legacy Hornet at the same point in its service life. Want to guess why? My two cents say the culprits are minimal manning, near-constant high op tempo, penny-wise/pound-foolish budget decisions (esp. during sequestration), and having killed their tankers and thus having to do a ton of buddy tanking. It's almost a blessing the Tomcat got spared most of these, and got to end on a high note as the "most capable strike fighter on the flight deck" with, comically, also the best availability and cost-per-flight-hour numbers for its last cruise (there are obviously some asterisks that belong on that figure).
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I can't find the posts at the moment, but Disco here exemplifies a couple of quotes that Victory205 made on this forum to the effect that no F-15 pilot he encountered who talked about the F-14's ostensible wing speedometer could come close to telling him what the mach sweep schedule was, nor could any of them who pooh-poohed the Phoenix tell him anything about what its parameters were like (because they hadn't seen the relevant documents). The bits attempting to cosplay as an aeronautical engineer in explaining design philosophy of airframes he'd never flown were the icing on the cake. Listen, every pilot will have something to say about everything he's flown and everything he's flown against. You'd be even sillier to take this guy's words at face value than you would be to consider every Snort/Hoser/Flash story to be gospel - you've got to balance eg. Disco's comments about F-15C vs F-14A against what "Okie" Nance says about the same fight and against "Puck" Howe's and "Jungle" Jones's comments about F-14D vs F-15C fight. In conclusion,
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Sorry to dredge an old topic, but did all these episodes disappear from YouTube? I can't find anything at the moment.
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The Tomcat was introduced in 1974, and delivered to Iran from 1976-1978. In 1978, the Persian-British singer-songwriter Freddy Mercury released the single "Fat Bottom Girls".