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Holtzauge

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Everything posted by Holtzauge

  1. I think the new AI are an improvement but I think the head-on accuracy has been improved a bit too much: Now it’s absolute suicide to go against the AI from head on. Seems you have to start some way out though since at shorter ranges they may just weave by at the merge. I usually set up a QM from max range 10 Km @ 1000 m alt and even if I start firing from >1Km the AI will bore right in and start firing at ca 0.7 Km and score decisive hits at ca 0.5 Km. At best it’s a draw with both going down but more often than not the AI comes out as the winner.
  2. Was busy doing some IRL flying this weekend (Discus b glider where the controls really stiffen up already at 200 Km/h IAS ) so only got the chance to test the 262 after the fix now and things have really improved since you can now do accelerated stalls at much higher IAS than before the fix. However, as far as I can tell while you now have elevator authority to stall at higher IAS, the slats still stay in right up to departure which seems strange. Have not yet tested enough to determine if this is purely a visual thing but if you compare with the in-game Me-109 slat kinematics these seem to match the angle of attack better since they pop out as expected also at higher IAS if you pull enough g's. Given the high aerodynamic forces involved in the leading edge suction that pulls out the slats (ballpark an order of magnitude greater than the mass forces), I have a hard time seeing mass forces having any major impact on the kinematics, especially seeing those will act more or less perpendicular to the slat rails at higher aoa. That being said, I'd like to join the chorus of users thanking IAmNotARobot for the fix and taking the time to interact with the forum community. The Me262 is great and a pleasure to fly and the tuning activities on the Me262 and the other planes in the sim are greatly appreciated!
  3. Good points and I think most of us flying in the sim understand that what we do in here is not the same as IRL. I don’t overly enjoy 5g IRL but doing it here is easy. Sure, in the sim you can yank the stick to your hearts content and it’s also surprisingly easy to shoot at high g-loads with accuracy which I seriously doubt would be the case IRL. However, all the points you make above are just as valid for all the other planes in the sim as well so I see no reason why the Me262 should be given special treatment in this department. So to make the Me262’s handling model consistent with the other planes, it should be possible to do accelerated stalls in the Schwalbe as well IMHO.
  4. Yep, I love it too! It's amazing the stuff we get to play with. However, that being said, I do hope they will look the high speed control over. IIRC then someone mentioned that the Dora had similar issues when it was released and that that was then fixed in a later update.
  5. Nope, sticks (elevators) are not geared so that the airframe can't be overstressed at high speeds: Elevators are usually geared to allow the pilot to be able to control the plane at low speeds, e.g. for landing configuration with flaps deployed at a max forward c.g. location. This gives you a certain design size and up deflection angle of the elevator needed. You can however to your hearts content pull the maximum on your stick up to the so-called max manouvering speed because the plane will stall before anything bad happens. However, when your speed goes above that you have to limit how much you pull or you will exceed the design limits. Using the attached figure the max manouvering speed for the P-51 is around 270 mph. But the same figure also shows that the static design limit, usually 1.5 times the max allowed limit, in this case 12g, can be reached at about 320 mph and above. There are second order things we could discuss like buffeting limits etc but in principle you can pull the wings of a plane and structural failures did happen in some cases, especially the Spitfire had incidents of this kind. Just ask VO101Kurfurst: He is an expert in documenting Spitfire weak points and can probably provide ample examples of Spitfires shedding wings. Returning to the Me262: I'm going to be careful to say that I don't say the FM is wrong but I will maintain that it should from a theoretical perspective given what we know about the flettner tab powered elevator on the Schawalbe be perfectly possible to pull the stick at higher speeds (barring compressibility effects) so that the slats come out and you get an accelerated stall. I have not seen the developers claiming that what we have now is the final product so I'm hoping to see this addressed but at the same time I'm going to start looking into it myself to see if there is any info around on this. TBH, AFAIK you are an experienced IRL pilot Zacharias so I'm surprised you don't seem to be more cautious about pulling hard on a direct control stick and trust the designers to limit the gearing. As an engineer I would find it very difficult to design a gearing that marries low speed control while not allowing overstressing above max manouvering speeds by a determined pilot.
  6. Well currently I have been using the adjustable tailplane as an "exploit" to bypass the limited elevator authority. Works quite well actually!
  7. I think at least a part of it is the stick force modeling: Try flying at low speed and pull back fully on your "virtual" stick and do the same at high speed: Go to external views and you can see that the angle the elevator moves is less at high than at low speed so the there is definitely a force based limitation there.
  8. Really fun taking the Schwalbe through it's paces and an amazing feat by the developers! Even managed a compressor stall flameout pulling to high aoa going over the top. A nice touch that but very embarrasing seeing the Spitfire I was trying to bag was not sporting enough to allow me to relight. That being said I'm also a bit surprised by the low elevator authority a high speeds in the current FM: The 262 has geared flettner tabs augmenting elevator authority so it should even be possible to get them overbalanced if you are not careful. I'm going to take my crew chief by the ear and tell him to fix it. Should be enough with a few mm adjustment on the bellcrank to make the tab move a tad more and then I can bag that Tommy next time round......
  9. Adding more Spitfire options would only make this great sim even better: I hope to see a +25 lbs option for the Mk9 and the Mk14 as a collector's plane. I'm sure most would buy it. I for one find the Mk14's long nose encasing the Griffon and the 5 bladed prop extremely attractive and the thing just reeks of power and potency.....
  10. Post 1: It's really informative to hear the opinion of someone who is so into Il-2 (like the rest of us!) compare the sim to the IRL experience. My chief takeaway from this is that it adds to the evidence of my long held belief that more wobbly is not more accurate and that as long as you have a decent flow of air over the tail you should be able to have sufficient directional control while taxiing. In addition to your testimony I think we have ample video evidence for the more of the type "on rails" like FM. A good example is the cockpit view from this Yak which looks to be rock solid without a trace of wobbliness. Anyway, I join the long line of envious simmers and congratulations Zacharias and thanks for sharing the experience! Post 2: +1: Many of us have the same opinion and I think and the trim tab analogy is dead on. Post 3: WTF! Why are my posts being auto-merged! I'm posting on two different subjects!!!
  11. Yes, thanks for all the tips and tricks to get the best performance/experience mix @Geronimo553. I'm still on the settings you posted in an earlier thread which boosted my frame rates around 50% with no really discernable impact on graphics quality and I will definitely tune some more based on this additional info later on when I get the time. It's great to get these kind of tips on what the different parameters do and how to combine them!
  12. Wassup? Is that a turbine I hear spooling up behind the screen? 😜
  13. Thanks for the info. Did wonders for my frame rate! 😀
  14. Maybe Monday! Right now I'm nursing a good Tempranillo and tomorrow I'm gonna go flying!
  15. OK, so here is the same dive scenario (from 6 to 1 Km in a 20 deg dive starting at 500 Km/h TAS) for both the 109K4 at 1.8 ata and G6 at 1.3 ata: The K4 is quite good: It dives the distance in the same time as the P-47 razorback but does so due to accelerating faster in the beginning while the P-47 is faster in the end. The poor G6 gets left hopelessly behind and one can only sympathize with late war "Nachwuchs" climbing up to meet Thunderbolts bearing down on them while stuck in a "Beule"....
  16. Believe me: I have been trying to figure this out as well: Why is the difference not bigger? Either it's as simple as the pilots thinking a difference of 250-350 m is a big difference and if you think about it from the pilots viewpoint it's all relative: So even if you cover 14 Km in the dive you don't perceive that, what you perceive is the other plane pulling away, i.e. diving better and getting that amount of separation in a 60 s dive is not negligible. If the difference actually should be bigger I'm more leaning towards the thrust modeling (prop efficiency loss due to supersonic tip speeds) at high subsonic speeds being at fault: The Spitfire's is actually quite good in the high speed drag department, with a late and low addition due to compressibility to a large extent due to the thin wing and clean design. Funnily enough most major fighters (the 109, Mustang and Fw190) had profiles (NACA 2R1, Laminar profile and NACA 230 series respectively) which were all actually quite good at high subsonic speeds although none had had that as a design criteria and was purely a fortuitous side effect of other design considerations such as aiming for a low drag and/or low pitching moment coefficient.
  17. Yes, I think there is an expectation that diving is a "get out of jail free card" and that was the theme in the Yak/Fw190 simulation Superetendard linked to earlier which showed that it can take an agonizingly long time to build separation if you get suckered into going slow in a better diving plane before disengaging. Regarding the 109 sure, I have both the K and G2 modeled so maybe the K at 1.8 ata would be good to compare to the Mk9 at +18 boost?
  18. Here is a C++ simulation (Overlay P-47 on top of Spitfire, time s, dive dist Km, TAS speed Km/h) for the 3Km at 350 Km/h TAS 20 degree dive in Papafly's video: Notice that in my simulation I get basically the same result: At the end of the dive they are within a hairs breadth. Also notice that at the bottom of the dive the P-47 is a bit faster while at 6 s into the dive the Spitfire is a bit faster: Just like theory would predict and quite in line with the results in BoX!
  19. @Kestrel: Good catch with the razorback versus bubble canopy: I actually have the D30 modeled (which I of course should have used initially as well!) and if you look at the results attached below its just like you say: The D30 does not pull away as fast as the razorback bringing the C++ and BoX results closer together but still, the D30 is ahead by about 275 m at 66 s into the dive. But 275 m in a dive of more than 14 Km is just a difference of around 2% so even in my simulations the anecdotal evidence that the P-47 should leave the competition standing is not really borne out. About the Spitfire accelerating better initially: That is only true if you start off at lower speeds but starting off as high as 500 Km/h then you are into the region where T<D almost immediately. @Papafly: When it comes to the validation of the C++ model: I have under the handle Holtzauge posted results from my simulations for more than 10 years on WW2 aircraft forums and you will have to judge the accuracy in the same way you do BoX: Compare the results with IRL data. I’m quite satisfied with the results so far and have received no feedback indicating any big problems with accuracy. However, that being said, modelling the subsonic drag rise due to compressibility and reduced propeller efficiency due to supersonic tip speeds is no easy task. About the speed difference between BoX and my C++ simulations: I noticed that as well and I don’t know how compressibility is modelled in BoX but in my C++ I have drag creep before the sharp drag rise when you start getting a lot of local supersonic flow and I would guess that the difference is due to different modelling here. Anyway, to conclude, even though the P-47 should be marginally better, the agreement in modelling between BoX and my C++ simulations seems pretty good since while the top speeds reached differ and while in BoX they may be neck to neck the 2% difference I get is not that much of a difference either……
  20. What I meant was that in the BoX scenario posted, i.e. a dive from 6 Km at 30-40 degrees dive angle starting at 500 Km/h then the P-47 should pull away from the Spitfire. Of course, if the planes fly the dive under different conditions then all bets are off…..
  21. Yup, but it does seem odd that there seems to be almost no difference in BoX: I think the old simulation results SuperEtendard linked above illustrates the point that it can take a while to build up separation in some cases but in the BoX comparison PapaFly posted here the P-47 really should pull away since you would pass top speed in a jiffy in that scenario.....
  22. No, you're quite right it does depend on the scenario but you can say that the P-47 should out dive the Spitfire in almost all cases: The exceptions would be a very steep dive where you would be forced to pull out before gaining any meaningful separation or starting from a very slow speed like close to stall from lower altitudes. However, in the test scenario from BoX the planes started off at 500 Km/h from 6 Km and then you pass D>T (i.e. top speed at a given altitude) very quickly and from then on the P-47 should start to pull away.
  23. Having given it some thought I think one could come up with a short numerical example to explain why the P-47 dives faster than the Mk9 at high speed: Beginning with good old: F=m*a in the plane of motion, i.e. the dive angle: T-D+m*g*sin(diveangle)=m*a Dividing both sides with m leaves the acceleration a=(T-D)/m+g*sin(diveangle) However, since g*sin(diveangle) is the same for both aircraft we can remove that from the comparison. This leaves that the acceleration component that differs between the two is proportional to the thrust minus the drag divided by the mass: a˷(T-D)/m From this follows that as long as the thrust is bigger than the drag then mass is not your friend and a lighter plane (all other things being equal) will accelerate faster. However, as soon as the drag is bigger, i.e. in a fast dive, the plane with the bigger D/m factor will dive faster. Since the dynamic pressure (q) is the same D can be represented with the parasitic drag area Cdo*S (We can discount the induced drag under these conditions) You can probably find a bit different numbers for drag area for both aircraft but in this comparison I’m going to use 5.54 sqft for the Spitfire Mk9 and 6.39 sqft for the P-47. For weight 3392 Kg for the Spitfire and 6006 Kg for the P-47. Comparing the D/m for both, the P-47 has a roughly 53% lower value meaning the acceleration deduction from the maximum vacuum value of g*sin(diveangle) due to drag will be less so at high speed it really should dive better…… QED
  24. Yes well that test was certainly a dive: Up to 80 degrees! Anyway its difficult to replicate for me. I can only do dive at a fixed angle or a dive followed by a zoom with dive and climb angle defined together with the amount of g's used in the pullout with the current code. Looks like in the test you linked that the dive angle varies quite a lot during the dive and I'm not sure how reliable the speed figures are in that test. Anyway, I think the comparison I did probably gives a good idea about the relative performance between the two......
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