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About =475FG=DAWGER

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  1. A simple understanding of metal fatigue would enlighten any engine modeling development. Combine that with a small amount of thermodynamics and the possibilities are limitless.
  2. Tell that to the F-15
  3. The idea that less RPM is easier on the engine than more at a given MP demonstrates how poor the developer understanding of how these engines work is. That is essentially backwards. I really need to stop reading these threads. You are saying that the minimum manifold pressure to hold 2651 RPM's will eventually cause the engine to fail? That is just plain dumb if true.
  4. Excellent point. Engine timers are the equivalent of the wings falling off after you fly normal combat for five minutes.
  5. There is a significant amount of drag associated with the dive flaps. The entire purpose of the dive flaps is to generate lift forward of the center of pressure to counteract the center of pressure moving aft due to the shock wave associated with local supersonic flow. This lift creation produces significant amounts of induced drag. Nearly identical designs are used on modern jets with the exception that they stick them on top of the wings to "spoil" the airflow and kill the wing lift. They allow faster descent. Well designed placement minimizes the pitch moment associated with their deployment and they definitely and a lot of drag and make the airplane vibrate when deployed at high speed. Slamming the spoilers to full in a Global Express at cruise speed feels like you slammed into a deep pothole.
  6. The point is that temperature should be relevant in ALL piston engine aircraft in the game. Getting engine modeling basically correct on some planes and using fairy tale land on others is not a good path forward.
  7. It is important to understand the difference between variable pitch propellers and constant speed propellers.
  8. It is interesting that you bring up War Thunder. In fact, War Thunder Simulator Battles has modeled engine thermodynamics in a way the actually resembles the real world. It is far from perfect but it works pretty well. I can use the WT P-38 series as an example. There are two modes, automatic engine controls and manual engine controls. In automatic, the mixture, prop, throttle, oil and water radiators are automatically controlled. In WEP, the radiators slam closed and you will quickly hit the overheat conditions. Out of WEP the radiator flaps will modulate in an attempt maintain temperature. There are significant drag penalties with the flaps open. In manual mode, the player can control mixture, prop RPM, throttle, oil and water radiator flap position. Flying in manual provides definite advantages. The developers have stated that for most aircraft, radiator flap positions above about 40% open really don't add much cooling but do add lots of drag. This tracks with real world operation of cooling devices that rely on Bernoulli to create a suction to create airflow through the radiator. The maps are tiny in War Thunder so one can fly around at combat power in some aircraft and some require cruise setting to stay cool. The map matters. Flying in a Battle of the Bulge map requires much less cooling than Sicily. In the P-38's we can fly around Sicily at 40% radiators and combat MP/3000 rpm. In cooler maps, 25% radiator will do. Slam into WEP and the engines begin to heat above normal temperatures. There are basically three stages or temperature ranges. The first range is essentially "Stay in this range for 5 minutes and engine damage will START to occur" , next is the "2 minutes and damage STARTS" and the final range is "you have 1 minute and damage will START to occur". The temperatures have inertia so trying to ride the timers may still result in a damage causing overheat. Also, the engines seem to have an overheat "memory". Once you get them into the upper temperatures they will quickly reheat even after cooling them back down to normal. Once you damage them, you can halt the damage progress most of the time by backing off the throttle. Get them too hot and the damage will continue to progress and may or may not stop before engine failure. Players are punished for not respecting the limits but not with instantly seizing engines. Sometimes one will seize on the way home at partial power. Sometimes both if you really push them hard trying to live. Aircraft with fluid injection lose WEP as a selectable power level once the tank is empty. Each aircraft has its own particular temperatures and varying rates of thermodynamic inertia so it isn't one size fits all. What works in a P-38 will cause a Spitfire to heat up very quickly. Some aircraft have manual oil and water radiators, others only one or the other and others no manual radiators. This isn't the perfect system nor has WT correctly modeled all facets of engine operation. Mixture controls are very basic although on the P-38 pulling the mixture, throttle, and propeller back will reduce fuel consumption accordingly and above 17,000 feet you cannot run in full rich. The engine loses power and runs rough. My point is that the "arcade game" has managed to come up with an engine management system that mimics how real world pilots operate without using egg timers. In the real world, run an engine too hot for too long and damage from minor to major will eventually occur based upon the severity of the excursion outside of the limits. It would seem the code is not nearly as complex as we might be led to believe and the reasons for not making it happen in IL2:BOX a bit mysterious.
  9. It would be great to see online simulators get rid of the parts shedding paradigm for dive limits and move on to something based on real world aerodynamics. Don't get me wrong, parts will shed above certain speeds but dive limits based upon losing pieces of the aircraft are based upon the weakest link, (usually a door. cover or some other non-structural component) not anything like a wing or stabilizer. Those things come off well past the dive limit and generally because the radial acceleration increases to the actual structural limit. Properly simulated mach effects should be the first consideration in modeling late war aircraft, not an after thought. It seems no one building flight models understands the process. Critical mach is reached (local supersonic airflow), the center of lift moves aft which pitch the aircraft nose down and the shortening of the elevator arm simultaneously reduces its effectiveness. The controls don't really "lock up". They are harder to move at speed and as the center of lift moves aft the same movement of the control surface does less. Aileron reversal is not aileron reversal at all. It is a structural weakness issue that is not related to mach effects. Quite simply, deflecting the aileron physically twists the wing above a certain speed and the wing twist rolls the airplane in the direction opposite the intended roll. The P-38 certainly suffered from mach effects, primarily because of its tremendous acceleration in a dive and relatively low critical mach number. It didn't come apart at mach .68 or even at mach .8. It came apart when the aircraft decelerated enough at low altitude for the elevator to regain effectiveness and the resultant extremely high G load ripped the tail off the aircraft. If the aircraft never slowed enough to regain elevator effectiveness, it drilled a smoking hole. This would generally hold true for any late war fighter from any country capable of terminal dives above Mach .7
  10. Properly modeled, the only thing the Dora does better than the P-38J-25-LO is top speed and dive speed. The P-38 turns better, accelerates better, and climbs better.
  11. I don't think you understand detonation.
  12. I fly both. My experience with War Thunder has been quite positive but I only fly in Simulator Battle in War Thunder. it seems the OP may have totally missed SB in WT. VR in War Thunder is definitely better overall than BoX Flight Models are essentially the same in the two titles. Engine management for the aircraft I fly is more realistic in WT than BoX. It isn't perfect and some of the individual models in WT are wrong but for the most part they do a much better job approximating real world engine management than BoX. BoX has a persistent world on a limited scale and WT doesn't. I only enjoy MP. Neither makes it easy. I still prefer the old school 24/7 arenas of the originals such as Warbirds but those days seem to be dead and gone.
  13. 18. Claiming that FM is incorrect without the required proof and starting a flame thread based on such claim is prohibited. The form for an FM claim consists of: short but consistent description of the claim; link to a reference and to a specific part of such reference that describes correct behaviour of a disputed element/situation; game track record and the list of conditions used to recreate disputed element/situation. Exception to this rule: FM discussion
  14. P-38 is the reason I bought Bodenplatte but after seeing the disastrous engine modeling on the P-47 there is a good chance the P-38 will be a horrid mess. I am prepared to be seriously disappointed. I expect the engines to use the three minute egg timer thermodynamics of the P-47. I suspect the P-38 will get assumptions applied to its FM instead of the facts. It accelerated better than any US fighter, could out turn at slow speeds every late war fighter produced by the USA or Germany with the maneuver flap and the boosted ailerons gave it tremendous roll rate, curing its only real weakness when it comes to virtual combat. I suspect it will not exhibit any of those characteristics but I sure hope I am wrong.
  15. Back in the 1990's I was flying unpressurized WWII vintage freight aircraft through some of the worst convective weather the US has to offer. The sense of smell was an important tool when navigating a line of thunderstorms. Even when I was flying jets capable of 51,000 feet equipped with the latest electronics, the lessons of those days aided my decision making. Online flying is completely sanitized. Missing are the myriad physical cues that are extremely important. Every sense is used, especially in WWII vintage aviation.
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