BlackLion213

The USN didn't start formal deactivation of the F-14A's glove vanes till 1991 or 1992, but lots of aircraft had inactive glove vanes well before this. The problem is that the glove vanes would act up commonly and required maintenance. Because the vanes were only somewhat useful at very high speeds (a place where fleet aircraft spent little time under normal conditions) they were often not a priority of repair. So instead of fixing them when a problem arose, the maintainers would just disconnect and cap the hydraulic lines. This was faster, easier, and less likely to require follow-up work. If the vane slid out a bit in flight, the maintainers would just push it back in and its weight would hold in place pretty well. This decision was often made squadron by squadron, so the fleet was pretty heterogenous in this respect. Some squadrons had operational glove vanes on nearly all aircraft while other had almost none. These practices where widespread starting in the early-mid 80s and by the early 90s the USN realized that the vanes really weren't needed. Hence the F-14A+ (later redesignated F-14B) and F-14D were built without them. As part of updating the F-14A fleet in the early 90s, the glove vanes were formally deactivated and wired/welded shut. So from the mid-80s to the early-90s, it was hit or miss on which F-14As had functioning glove vanes. -Nick

Just an FYI, the max instantaneous turn rate for the F-14 at 5000' is ~22 degrees per second at a gross weight of 56,000 lbs....that's really high! The airplane is a remarkably good turner, despite the mis-information is out there. :) -Nick

Jet wash and wake turbulence certainly would have effects on the TF30 like any engine. Its not a matter of simply flying through wake and experiencing a stall, but the presence of wake does change the engine's stall margin. This effect is not just from other aircraft, but also from events such as missile launches and firing the M61 (as noted in NATOPs). Our F-14D pilot was testing out the wake effect yesterday and pointed out that even the F110 would sometimes experience a compressor stall (namely pop stalls I think) from following in a tight trail behind another aircraft - hence the reason why formations are staggered by altitude or lateral offset. These issues are not a part of DCS at present and excited to bring them to the sim with the F-14. Swither may have simplified things a bit with his statement in the interview, but this new wake turbulence model effects both engines and airframe (depending on distance and position within different parts of the wake, loss of lift may occur for example). The TF30 will be more sensitive to it than the F110, but this is not like "fly through jet wash and TF30 stalls". Its a cool feature and I think you'll like it once you try it. :) -Nick

I forgot to mention, the new Heatblur jet wash effect does effect TF30 stall margins: https://forums.eagle.ru/showthread.php?p=3665152#post3665152 -Nick

The current wake system is not just F-14 to F-14, the effect also occurs with other aircraft. The effect is currently implemented with tankers (KC-135, KC-130, etc) and other USN aircraft. It is still WIP and requires tuning, but is a nice addition for realism. Also, this effect does effect TF30 stall parameters. :) -Nick

The decision to do the F-14A has not delayed the B in any way shape or form. Given their significant commonality of systems and airframe it makes sense to do both for reasons mentioned above. There just 4 significant changes made from the F-14A to the F-14A+/B (same airplane, just designation change in 1992): Engines (with associated cockpit changes), RWR, DLC, and gun venting. As far as the reliability of the TF30, it was an issue but not as bad as portrayed in the OP's quote. At either zone 5 AB or full mil-power, the engine was pretty reliable. Stall margin definitely decreased at lower RPMs and throttle transients at high AOA were a bad idea. Given its less than ideal thrust, pilots generally didn't perform maneuvers much at anything less than mil and most ACM was at zone 5. There were throttle restrictions that were dependable for keeping pilots out of trouble (don't move the throttles at high AOA and don't perform high AOA maneuvers at settings besides mil-power or zone 5 AB). Also, there were 2 forms of compressor stalls: "coughs" and hung stalls. Coughs are rapidly clearing stalls that don't require intervention. These did not harm the engine, but could be considered "shots across the bow". Hung stalls were the ones that placed the crew at risk of departure, spins, and engine fires. Ironically, the engine didn't fully flame out that often, but a hung stall means the engine will roll back and heat up. It refuses to respond to any command, but shutting things down and will result in critical engine temps within 30 seconds or so. So if you handle the engines carelessly (like many DCS users probably would at first :) ), then there is a real risk of compressor stalls. However, watch things a bit and stalls will be pretty uncommon. -Nick

Nope. I'm a surgeon, but commenting on what I've learned as a Heatblur F-14 tester. So any comparison is between the DCS: F-14B and DCS: F-15C, not the real airplanes. :) Turning off Pitch SAS doesn't change handling much. It leads to a bit more sensitivity and tendency towards OIO since SAS slows some initial inputs and limits max deflection of the stabilators. But the net effect does not markedly change handling. Disabling Yaw SAS has a much bigger effect. The nose wanders a lot more in routine flight and with roll inputs. It also takes way longer for rudder inputs to damp out and wing rock is far more likely to occur at high AOA. Overall, it is the most helpful SAS and turning it off leads to messier handling and increases the risk of control problems or departure. Roll SAS is a mixed bag in terms of benefits. Roll SAS on allows for more rapid roll rate and the system limits max roll to 180 deg per second. Since roll is much quicker with wings swept, you will sometimes see the system modulating max roll rate during sustained aileron rolls with wings swept, leading to a very subtle "racheting effect" (only noticeable with sustained roll and pretty subtle). No such limiting occurs with roll SAS off, but max stabilator deflection is limited so the max roll rate is not as fast (at least compared to the max attainable rate for the first 90-180 deg with roll SAS on). So turning it off leads to a slower roll rate, but also improves high AOA handling. Above 17 units or so AOA, the pilot should be using the rudder as the primary input for roll. However, with roll SAS on the system will try to stop roll that doesn't have an associated lateral stick input. This leads to more yaw during attempted rudder rolls during mild to moderate buffet (~14-23 units of AOA) and "cross controlling" of the aircraft. So handling at higher AOA is impaired with roll SAS on, so you should turn it off for BFM. Also, the roll SAS system does not account for AOA. So when roll reversal onsets (above 21-22 units AOA), the system will still give inputs opposite of the detected (and uncommanded) roll, which will actually accelerate the roll during this flight regime. Roll reversal also tends to build the AOA and can lead to yaw, this chain of events places the aircraft at higher risk of departure. So its another good reason to disable the system before ACM or BFM. Are these the answers you were looking for Julian? Or other details? -Nick

Yep, VF-21 off Constellation. :) -Nick

No, it feels quite different. In fact it feels quite different from any aircraft in DCS currently. Compared to the F-15C it is quite a bit slower in roll and generally less precise in all axes with a bit of lag in pitch. However, it also turns better than the F-15C at all speeds below Mach 0.9 and below 25,000'. The handling in the landing configuration is also much "messier". There is a moderate amount of adverse yaw at approach AOA and coordinated rudder and aileron is quite important for proper handling during approach. It also requires exclusive use of the rudder for roll inputs above 20 units AOA and has significant roll reversal above about 20 units AOA as well. It also lacks any pitch trim compensator so you need to frequently trim for any changes in speed or wing sweep. Wing sweep affects many of the general handling characteristics as well, including roll rate (which speeds up as the wings sweep) and turn efficiency. Finally, it is a far more "talkative" airframe with consistent feedback offered by airframe buffet allows it to clearly communicate AOA. Allowing the pilot to comfortably differentiate cruise AOA from ideal STR AOA and max performance AOA, along with uselessly high AOA. Its a fascinating module to fly that isn't quite like anything in DCS. It's turn performance is mighty with a max ITR pitch rate of 23 degrees per second, while its STR at medium to low altitude matches the F-15C and F-16C (14 deg per second). Also, its fast....really fast. Similar to the F-15C in level acceleration. I think people will be quite taken with the overall experience. Its a bewitching machine! :) -Nick

The pilot can shoot all weapons including the AIM-54. :) The workload is pretty evenly split between the pilot and RIO. This actually makes the F-14 module pretty approachable for new users despite its detail. While the aircraft's handling takes a bit of practice to master, it is very straightforward in normal flight and cruise AOA (3-10 units). The most complex systems belong to the RIO and Jester manages those, so the pilot's primary interests are basic navigation (INS operated by RIO), managing the airframe and flight, and managing weapons (including auto-acquisition modes for the AWG-9, which are quite handy). -Nick

So this photo is pretty good, but with one notable error: there is no "F-14A+" cockpit since it is the exact same as the F-14B (logically since the F-14A+ and F-14B are the same airplane). The cockpit labeled as "F-14A+" in the photo is a F-14A cockpit upgraded with the ALR-67, which is an upgrade applied to some F-14A squadrons that were expected to stick with the aircraft past the late-90s (like VF-154 and VF-211). All F110 powered F-14s have the LCD engine gauges as depicted in the photos to the right. There is a consistent confusion around the issue of "F-14A+" vs "F-14B", but they are the same airplane. Before 1992 the airplane was called the F-14A+, but after 1992 it was re-designated the F-14B with no associated hardware or software changes - just a "label" change. :) -Nick

Probably because the political justification was the protection of the CVBG against bombers and the original USN doctrine dictated using the AIM-7 against fighters and reserving the AIM-54 for bomber raids. However, this doctrine was intended to save money since the AIM-54 was viewed as "over kill" against the expected threats, namely the MiG-21 with no forward aspect capability. Once the MiG-23 was in widespread use, plans changed and doctrine allowed squadrons to choose what ever weapons they wished for the anti-fighter role. -Nick

Looks even better in VR. :) -Nick

All F-14 variants were upgraded with LANTIRN: It was a fleet wide upgrade irrespective of F-14 variant. -Nick

Yes, the ASM should model this behavior. :) I say should because the current nozzle animation is simplified, so I haven't verified yet though the functionality is there. -Nick

As others said, its related to the shutdown procedure and because of the function of the weight-on-wheels switch (WoW). Both the TF30 and F110 engines have an idle pop-open function for the nozzles at idle during ground operations (WoW switch is active). In the air, the nozzles are always closed unless afterburner is commanded. There is a convention for shutting down the right engine since it drives the hydraulic pump for the flight controls, while the left engine drives the combined system. The right engine is shut down first to check function of the hydraulic transfer pumps as a routine maintenance check. When the right engine is shut down, there is still electrical power and the WoW will continue to send a signal to keep the nozzle open. When the left engine shuts down, the generator drops off line around 55% N2 so the WoW switch is disconnected. The left engine then defaults to "in-flight mode" and residual fuel pressure (nozzles are driven by fuel pressure) will still be sufficient to close the nozzle as the engine spools down. The F110 powered Tomcats do this too, but as another member noted the weight of the petals is sufficient to pull the nozzle open with the effects of gravity. So the left nozzle only stays closed for a few moments. I find the chain of events sort of interesting and worth sharing. :) -Nick

Well, it really is more of a 1988-1995 F-14B, but Heatblur is working out the best way to integrate LANTIRN from a function and artwork standpoint (cockpit features that change when the LANTIRN is loaded, for example). More to come on the topic in the future. :) -Nick

Its really fun and you learn a ton about the real airplane. :) The first Pilot testing was live (at my house actually - best meeting point for testing since the FM developers flew out as well) and that was a really cool day. Having the pilot try things in VR led to a lot good conversations about the F-14 and sea-stories in general. On the other hand, it can be hard to hear constructive or negative feedback. The FM developers and testers have invested a lot of time trying to match docs and reported behavior. You become pretty invested in your interpretation and it can be tough when you hear "oh boy.....we have a lot of work to do here" and then get a long list of things that are wrong and need to be fixed. However, that is the only way that you get things truly right and you have to be ready to redo and endlessly adjust things. It also makes it way more gratifying when the pilots say that it feels like a Tomcat! Knowing that it wasn't always the case and a lot of work was invested to get it there. The F-14A and F-14B will both use AFCS. There may be some version with DFCS in the future, but nothing concrete yet. I personally think this is the better approach since the AFCS Tomcat is so much fun to fly and has a ton of personality. With DFCS, so much of the bad behavior was tuned out and it starts to feel a lot more like the Hornet - very straightforward to fly. But that also takes out many of the fun aspects as well. The Tomcat is quite straightforward to fly under normal conditions, but can be a bit of a handful at high AOA or in the landing configuration (bit directionally weak and prone to dutch roll with lateral control inputs). However, if you learn a few straightforward techniques, then things are straightforward and the aircraft remains controllable even up to pretty extreme conditions. This makes the module very rewarding and keeps you coming back to fly over and over again. :) Without those traits, it loses some of the magic imho. But who knows what the future holds, my guess is that something with DFCS will be released eventually.... -Nick

Short answer is: yes, but not called a PFM. Long answer is: the model is an EFM meaning the flight model was developed outside of ED and in fact is a program that runs outside of DCS. It receives atmospheric and physical parameters (speed, AOA, etc) from DCS which is then fed into the Heatblur FM program. The program then crunches all the info and feeds forces to the rigid physics model inside of DCS. I think a lot of people figure that FM development is a lot like a "mad libs" word game where you take some aircraft specifics and plug it into a framework that exists in DCS - that is true for SFMs. But PFMs/EFMs are clean sheet mathematical descriptions of the aerodynamic and physical forces that effect the airplane. So instead of a mad libs we are talking about a blank sheet of paper.....pretty intimidating. In the case of the F-14, the FM was developed from NASA wind tunnel testing, NASA aerodynamic evaluation data, USN real world performance data (covering all aspects), USN documentation for handling/testing, USN docs for the AFCS system, flight control systems, USN weight and balance documentation (which proved to be quite important for replicating behavior), detailed engine documentation/dynamics modeling, etc, etc, etc.....a lot of stuff! All of this information is then digested and converted to equations, coefficients, look-up tables, and all that stuff by the FM developer. The F-14 FM actually has 2 FM engineers/coders/developers. The lead is a joint PhD in engineering and computer science (Mechatronics) while the other's day job is as an FM developer for Level D simulators (private and light commercial jets). Add to that, the FM has over a hundred hours of real F-14 pilot evaluation time resulting in many adjustments. We thought the FM was in pretty good shape a year ago when the pilots first stated giving feedback. Well a year later we have adjusted a lot of stuff! Things are actually quite different than they were back then (even without changing the core aero data from wind tunnels and other sources). FM development means a lot of very fine tuning that can have big effects. Without all the pilot input, things would actually feel pretty different - even though everything would still match the data. Aircraft feel is surprisingly dependent on small details. :) I am happy to say that our pilot SMEs are quite happy with it, even as we adjust a few more details (like how much roll rate changes with wing sweep, as Cobra mentioned). One of our best SMEs (very detail oriented and he uses DCS habitually - he has made a huge contribution to the module!) recently described the FM as a "game changer" - so we are very happy with the depth and accuracy. So like I said....long answer. :) In summary: it's really good! :D -Nick (Heatblur Tomcat tester)

No, but it received the same DFCS upgrade as the rest of the F-14 fleet. DFCS makes quite a big difference in handling: more consistent roll rate, elimination of dutch roll in landing configuration, ARI that eliminates roll reversal and allows pilots to use lateral stick across all AOA and conditions. So it bridges the gap pretty well between FBW and analog flight controls. But all F-14s used the same control system irrespective of model. The only big change was the addition of DFCS which was implemented fleet wide (actually started with the F-14A since if offered bigger safety benefits vs F110 Tomcats). -Nick

Here is the article mentioned by Captain Dalan: https://foxtrotalpha.jalopnik.com/this-topgun-instructor-watched-the-f-14-go-from-tomcat-1725012279 Discussion on the AIM-54 is in the middle of the article. -Nick

Indeed, it was generally a problem with OBC, not the ramps themselves. -Nick

Well, it will be a random failure for those with the feature enabled, but all this stuff is quite rare. Battle damage is a more realistic scenario for seeing the effects. Even the TF30's famous compressor stalls were not that common in practice. Of our 2 F-14A SMEs, both had only 1 stall in their entire career (1400 hours and 2000 hours in the A). And one of them was related to engine that was out of tune (developed excessive TIT at full mil-power) and both stalls spontaneously cleared. So these features won't surface much, but are possible and built into the model. They will also be trigger-able via the ME and such. -Nick

Hi Vitor, We now have very detailed data on ram drag and it is fully implemented. Took longer to find the data than expected, but we managed to find exactly what we needed. :) -Nick