zcrazyx Posted January 19, 2016 Posted January 19, 2016 I just wanted to ask if there is Icing in DCS 1.5 for the P51D specifically with the carburetor as I just noticed that on multiple occasions the Carb heat gauge on the P51D has read negative 50oC and at that temp it should stop the engine from working, this happens between 15 and 40k feet no matter what i have the Carb cold and hot air controls at, I also noticed that the P51D and Mig 21 Do not get canopy icing. I have tested this at different heights and air temperatures to about negative 20 degrees. The only time i had a noticeable issue with the aircraft that may relate to the carburetor is after i came out from a dive from 40k Feet into snow when the temp was negative 20. I also checked the after crash report where the failures are to see no carburetor failures or issues. So is Icing apart of the game? If so, what areas or aircraft?
Art-J Posted January 19, 2016 Posted January 19, 2016 Modelling of icing is rather simplified in DCS, it doesn't always follow cloud coverage - you can get it even in clean air (it seems to be only temperature related, no humidity modelling I think) and it affects different aircraft in different manner. In P-51 pitot tube icing is there for sure, although it's more of a problem in winter map conditions. Never experienced low temp gun jamming or carb icing, but I rarely fly on winter map anyway. On the other hand, flying Mi-8 low over the ground in winter, or at high altitudes, without engine intakes heating turned on guarantees icing problems pretty fast. i7 9700K @ stock speed, single GTX1070, 32 gigs of RAM, TH Warthog, MFG Crosswind, Win10.
Vitormouraa Posted January 19, 2016 Posted January 19, 2016 Sorry for asking this, but in the Mustang, when you turn the Magneto to Right or Left, it doesn't change the RPM? it should change, the RPM should decrease a lot. Why? SplashOneGaming Discord https://splashonegaming.com
Zabuzard Posted January 19, 2016 Posted January 19, 2016 Icing is possible between -15°C and +5°C, for other temperatures it is extremely unlikely that icing occurs. If you are flying high the low air density makes it impossible for ice to build. However AFAIK icing is not modeled in the P-51D Mustang at this moment. Note that heating effects are modeled Read the following thread for more info about the carburetor: http://forums.eagle.ru/showthread.php?t=155614
zcrazyx Posted January 19, 2016 Author Posted January 19, 2016 Modelling of icing is rather simplified in DCS, it doesn't always follow cloud coverage - you can get it even in clean air (it seems to be only temperature related, no humidity modelling I think) and it affects different aircraft in different manner. In P-51 pitot tube icing is there for sure, although it's more of a problem in winter map conditions. Never experienced low temp gun jamming or carb icing, but I rarely fly on winter map anyway. On the other hand, flying Mi-8 low over the ground in winter, or at high altitudes, without engine intakes heating turned on guarantees icing problems pretty fast. Pitot tube icing and failure is definitely modeled as you see it in the failure list however i believe icing does not show, surely because of the height the temperature would be below freezing and the air hitting the carb would cool it down and start icing when it comes into contact with nearby heat?
zcrazyx Posted January 19, 2016 Author Posted January 19, 2016 Icing is possible between -15°C and +5°C, for other temperatures it is extremely unlikely that icing occurs. If you are flying high the low air density makes it impossible for ice to build. However AFAIK icing is not modeled in the P-51D Mustang at this moment. Note that heating effects are modeled Read the following thread for more info about the carburetor: http://forums.eagle.ru/showthread.php?t=155614 Jets experience icing at 28000 - 38000 feet and i was at the same in the Mustang, hmm i don't know though, what you said does and does not make sense, the carburetor would be warm i imagine so surely the cold air hitting heat would heat up and form water droplets that could then cool around the carb.
DblAAssassin Posted January 19, 2016 Posted January 19, 2016 Sorry for asking this, but in the Mustang, when you turn the Magneto to Right or Left, it doesn't change the RPM? it should change, the RPM should decrease a lot. Why? A little off topic... It may be a bug in the 1.5 version of the game. The manual says to looks for a maximum of 100 RPM drop in right magneto and maximum of 130 RPM drop in the left magneto. Are you doing the magneto check at the end of your power check (at 2300 RPM)? Hardware: Saitek X56, TrackIR, HP Reverb G2
Art-J Posted January 20, 2016 Posted January 20, 2016 (edited) Jets experience icing at 28000 - 38000 feet and i was at the same in the Mustang, hmm i don't know though, what you said does and does not make sense, the carburetor would be warm i imagine so surely the cold air hitting heat would heat up and form water droplets that could then cool around the carb. You've got things mixed up. Water vapour (or any gas for that matter) condenses when pressure increases or temperature decreases below certain point. In all carbs the decrease is caused by intense fuel evaporation, while carb heat prevents droplets from forming ice on carb elements below the nozzle. It all doesn't matter anyway, because as I said, the DCS doesn't seem to model humidity-related effects. Even vapour trails behind the wings are scripted to appear in any conditions, just when pulling certain Gs. As for magnetos, I recall the drop is there, but very small (remember that quoted 100 is max value) and it's been like that since version 1.2 era. Edited January 20, 2016 by Art-J i7 9700K @ stock speed, single GTX1070, 32 gigs of RAM, TH Warthog, MFG Crosswind, Win10.
Weta43 Posted January 20, 2016 Posted January 20, 2016 Even vapour trails behind the wings are scripted to appear in any conditions, just when pulling certain Gs Actually, they're more likely in DCS in overcast situations, and less in clear. Cheers.
Ramstein Posted January 20, 2016 Posted January 20, 2016 not saying the mustang has which manifold heating devices, but the engines going way back either had heated manifold for exhaust ducts, water ducts, or both... either auto or manual... ASUS Strix Z790-H, i9-13900, WartHog HOTAS and MFG Crosswind G.Skill 64 GB Ram, 2TB SSD EVGA Nvidia RTX 2080-TI (trying to hang on for a bit longer) 55" Sony OLED TV, Oculus VR
Zabuzard Posted January 20, 2016 Posted January 20, 2016 Yo-Yo on carburetor icing, posts from mid 2013: http://forums.eagle.ru/showpost.php?p=1764977&postcount=4 http://forums.eagle.ru/showpost.php?p=1766116&postcount=10
zcrazyx Posted January 20, 2016 Author Posted January 20, 2016 (edited) Yo-Yo on carburetor icing, posts from mid 2013: http://forums.eagle.ru/showpost.php?p=1764977&postcount=4 http://forums.eagle.ru/showpost.php?p=1766116&postcount=10 So the manual indicates that the green arc is for normal operating temperature however Yo-Yo says its where icing is possible, which is it? In the instance of -50oC temp is it even possible for a carb to operate in that temperature? EDIT: In the manual it mentions that anything in green is marked as safe or normal operating temperature so I still don't understand how the carb can read -50oC and still operate, surely the butterfly valve would freeze? Edited January 20, 2016 by zcrazyx
Flamin_Squirrel Posted January 20, 2016 Posted January 20, 2016 Icing is possible between -15°C and +5°C, for other temperatures it is extremely unlikely that icing occurs. If you are flying high the low air density makes it impossible for ice to build. That's not right at all; it can occur over a much wider range than that.
Mike Busutil Posted January 20, 2016 Posted January 20, 2016 (edited) Sorry for asking this, but in the Mustang, when you turn the Magneto to Right or Left, it doesn't change the RPM? it should change, the RPM should decrease a lot. Why? Vitor, Check out this video of the procedure at 17:14 mark. The RPM drop is very small because the propeller governor automatically controls propeller pitch to maintain a constant speed [ame] [/ame] Edited January 20, 2016 by Mike Busutil [sIGPIC][/sIGPIC] Checkout my user files here: https://www.digitalcombatsimulator.com/en/files/filter/user-is-Mike Busutil/apply/
pr1malr8ge Posted January 20, 2016 Posted January 20, 2016 You've got things mixed up. Water vapour (or any gas for that matter) condenses when pressure increases or temperature decreases below certain point. In all carbs the decrease is caused by intense fuel evaporation, while carb heat prevents droplets from forming ice on carb elements below the nozzle. It all doesn't matter anyway, because as I said, the DCS doesn't seem to model humidity-related effects. Even vapour trails behind the wings are scripted to appear in any conditions, just when pulling certain Gs. As for magnetos, I recall the drop is there, but very small (remember that quoted 100 is max value) and it's been like that since version 1.2 era. actually you're wrong about this.. First things first, condensing water is not due to pressure increase. If you have ever filled a HPA tank i.e. an SCBA, SUCBA, Paintball tank you will notice that it actually increases in temperature. The reason for the temp drop is due to a decrease in fluid pressure causing the temp to drop. This is part of the venturi affect. I think you're confusing pressure increase with velocity increase. as far ambient temp you will notice carb ice mostly in the 60-70*F range For the WIN [sIGPIC][/sIGPIC]If your desired effect on the target is making the pilot defecate his pants laughing then you can definitely achieve it with a launch like that.
Flamin_Squirrel Posted January 20, 2016 Posted January 20, 2016 actually you're wrong about this.. First things first, condensing water is not due to pressure increase. If you have ever filled a HPA tank i.e. an SCBA, SUCBA, Paintball tank you will notice that it actually increases in temperature. The reason for the temp drop is due to a decrease in fluid pressure causing the temp to drop. This is part of the venturi affect. I think you're confusing pressure increase with velocity increase. as far ambient temp you will notice carb ice mostly in the 60-70*F range Art-J is correct, I think you've just miss read his post slightly. Art-J said: "condenses when pressure increases or temperature decreases", (note the "or"). I suspect you read it as "when pressure increases temperature decreases". While you're absolutely right that temperature will increase with pressure, the ability for air to absorb moisture decreases with pressure.
Art-J Posted January 20, 2016 Posted January 20, 2016 I should've been more clear. Although temp drop caused by pressure drop can get the vapour below dew point indeed (as for example wing/prop/rotor tip trails clearly show), in carburetors the fuel vaporization has much stronger cooling effect and is considered to be predominant factor when describing carb icing risk. i7 9700K @ stock speed, single GTX1070, 32 gigs of RAM, TH Warthog, MFG Crosswind, Win10.
NightRush Posted January 21, 2016 Posted January 21, 2016 (edited) Sry double post Edited January 21, 2016 by NightRush Double post
NightRush Posted January 21, 2016 Posted January 21, 2016 I dont believe there should be ANY engine icing on a Mustang. For one, the Merlin 266 does not have a true carburetor. Its called a carburetor but that's just to trick you, its a development of a carb but not actually; its somewhere between a fuel injection engine and a carb. But the British and not that inventive when naming things. The fuel is actually atomized through a fuel injector upstream. There is no real venturi inside the neck of the carb, instead there are pressure sensors that control the fuel flow to the injectors. Second to this, is the temperatures the engine runs at, the temperature of the charged air/fuel ratio at the aftercooler (its technically not an inter-cooler) is huge, you will have to forgive me I cant remember the temperature but its 100's of degrees Celsius. The supercharger stages are literally in contact with the carb body, that heat transfer would stop almost 100% of icing. However a situation when you *might* see icing is at those extreme low temperatures, high humidity and a small throttle opening. Basically the throttle butterfly being in a closed position creates a venturi effect. This would be a very very specific case!
zaelu Posted January 21, 2016 Posted January 21, 2016 It would be nice to have at debriefing also a Crew Chief debriefing where "he" could point out errors in engine management during flights. Or in Pilot Log. [sIGPIC][/sIGPIC] I5 4670k, 32GB, GTX 1070, Thrustmaster TFRP, G940 Throttle extremely modded with Bodnar 0836X and Bu0836A, Warthog Joystick with F-18 grip, Oculus Rift S - Almost all is made from gifts from friends, the most expensive parts at least
pr1malr8ge Posted January 21, 2016 Posted January 21, 2016 (edited) Art-J is correct, I think you've just miss read his post slightly. Art-J said: "condenses when pressure increases or temperature decreases", (note the "or"). I suspect you read it as "when pressure increases temperature decreases". While you're absolutely right that temperature will increase with pressure, the ability for air to absorb moisture decreases with pressure. Yes I did just re-read what he said. Did not realise that part of what he was saying was in reply to vapor clouds.. How ever his theory on carb ice being linked to evaporation is only a "minor" part of carb ice. as I stated the primary cause is due to a drop in pressure and a velocity increase. Edited January 21, 2016 by pr1malr8ge For the WIN [sIGPIC][/sIGPIC]If your desired effect on the target is making the pilot defecate his pants laughing then you can definitely achieve it with a launch like that.
Vitormouraa Posted January 21, 2016 Posted January 21, 2016 Vitor, Check out this video of the procedure at 17:14 mark. The RPM drop is very small because the propeller governor automatically controls propeller pitch to maintain a constant speed Hey Mike, I was talking with my friend Sales, he's a pilot. He says the RPM should drop to ~100RPM. And my other friend, he's mechanical and he said the same thing. I'm sure the Mustang isn't a rule exception. SplashOneGaming Discord https://splashonegaming.com
Mike Busutil Posted January 22, 2016 Posted January 22, 2016 (edited) It should drop a maximum of 100 RPM when the right magneto is cut and drop a maximum of 130 RPM when the left magneto is cut from 2300 RPM. Not drop to 100 RPM. So if you run up to 2300 RPM and cut the left mag, the RPM should drop to 2170 RPM. If you run up to 2300 RPM and cut the Right mag, the RPM should drop to 2200 RPM. So not very much drop at all. You can see exactly that in the video. Edited January 22, 2016 by Mike Busutil [sIGPIC][/sIGPIC] Checkout my user files here: https://www.digitalcombatsimulator.com/en/files/filter/user-is-Mike Busutil/apply/
Vitormouraa Posted January 22, 2016 Posted January 22, 2016 It should drop a maximum of 100 RPM when the right magneto is cut and drop a maximum of 130 RPM when the left magneto is cut from 2300 RPM. Not drop to 100 RPM. So if you run up to 2300 RPM and cut the left mag, the RPM should drop to 2170 RPM. If you run up to 2300 RPM and cut the Right mag, the RPM should drop to 2200 RPM. So not very much drop at all. You can see exactly that in the video. Ohh it's working so? I thought it should drop to 100RPM. Thanks Mike! I fly the Mustang just4fun, it's not as the Hawg. :) SplashOneGaming Discord https://splashonegaming.com
ShuRugal Posted January 22, 2016 Posted January 22, 2016 Ohh it's working so? I thought it should drop to 100RPM. Thanks Mike! I fly the Mustang just4fun, it's not as the Hawg. :) If the engine dropped to 100 RPM, it would die. There are exceptionally few engines capable of maintaining an idle that low, and all the examples i am aware of are massive (earth-moving or naval sized) diesels.
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