osram Posted March 8, 2013 Posted March 8, 2013 Can someone explain why I might get the impression that the SU25-T stalls way more often and has actually less uplift flying at around -5 degrees Celsius or colder temperatures compared to around 15 degrees celsius? Noticed the difference playing two different MP maps... and it somehow doesn't make much sense, since the "general opinion" is usually that cold weather provides better flying characteristics. The difference is really noticeable... and somewhat annoying, even harder to fly the SU in cold temps.
joey45 Posted March 8, 2013 Posted March 8, 2013 Thought is was worse in colder temps... The only way to make sense out of change is to plunge into it, move with it, and join the dance. "Me, the 13th Duke of Wybourne, here on the ED forums at 3 'o' clock in the morning, with my reputation. Are they mad.." https://ko-fi.com/joey45
Hamblue Posted March 8, 2013 Posted March 8, 2013 Is icing modeled? Asus Sabertooth P67 Motherboard 2600k CPU, 16 gig DDR3, 1600. Samsung 830, 256 gig hard drive, GTX780 Video Card, Warthog Hotas, Razer Mamba mouse. Saitek Combat Rudder Pedals. Trackir 5, Verizon FIOS 25Meg Up/Down
Corrigan Posted March 8, 2013 Posted March 8, 2013 ^ No, not to my knowledge. Win10 x64 | SSDs | i5 2500K @ 4.4 GHz | 16 GB RAM | GTX 970 | TM Warthog HOTAS | Saitek pedals | TIR5
Weta43 Posted March 9, 2013 Posted March 9, 2013 Noticed the difference playing two different MP maps Altitude ? Cheers.
whartsell Posted March 9, 2013 Posted March 9, 2013 Cold air is denser than warm air. So all thing being equal the ac will have more lift. Other factors to take into account are humidity, pressure, and weight. This is a short list Arduino,EOS and Helios Tutorial Static ATC menu mod
Hawk_5 Posted March 9, 2013 Posted March 9, 2013 Specific testing with equal loads and fuel in both seasons is needed to ensure this is not a subjective assessment. Maybe one of the testers already knows whether flight performance variation is modelled in different temperatures? Hawk_5 Modules: A10C, BS2, FC3, P51, CA, UH-1H, Mi-8MTV2 System: Gigabyte GA-X79UP4 MB, intel 3930k, Coolermaster Siedon 120M liquid cooled, Corsair Vengence Red 16GB 2133Mhz, Gigabyte Geforce GTX680 2GB Super o'clk, intel 520 SSD 240GB, Seagate Barracuda 2TB HD, Coolermaster Silent Pro 800W PS, Coolermaster CM690 II Case
Weta43 Posted March 9, 2013 Posted March 9, 2013 Maybe one of the testers already knows whether flight performance variation is modelled in different temperatures? It is, which is why I asked about altitude Cheers.
Hawk_5 Posted March 9, 2013 Posted March 9, 2013 OK. Try reading pages 48, 49 & 50 of the SU25T Flight Manual PDF. It covers all aspects of the SU25T Advanced Flight Model. Study that and see how & what best applies to what your experiencing. Hawk_5 Modules: A10C, BS2, FC3, P51, CA, UH-1H, Mi-8MTV2 System: Gigabyte GA-X79UP4 MB, intel 3930k, Coolermaster Siedon 120M liquid cooled, Corsair Vengence Red 16GB 2133Mhz, Gigabyte Geforce GTX680 2GB Super o'clk, intel 520 SSD 240GB, Seagate Barracuda 2TB HD, Coolermaster Silent Pro 800W PS, Coolermaster CM690 II Case
osram Posted March 10, 2013 Author Posted March 10, 2013 I am assuming it has to do with altitude.. The "problem-mission" takes place within large mountain-valleys mostly. since it's rather difficult to judge altitude in mountainous area... bottom mountain-valley level doesnt quite feel "much" higher, than regular plains areas. And even flying a bit further up, while turning back onto targets over the mountains at around 2-3000m (barometric?) altitude, it somehow feels exceptionally worse than flying at around 2-3k altitude over flat terrain AND around 20 degrees Celsius higher temperature on the "better/warmer" map. I don't think the SU25-T normally uses radar altitude, right.. its barometric? What I thought about is possibly turbulences/wind around mountains.. but I dont think that is actually modeled in DCS, is it?
Hamblue Posted March 11, 2013 Posted March 11, 2013 Cold air is denser than warm air. So all thing being equal the ac will have more lift. Other factors to take into account are humidity, pressure, and weight. This is a short list Just to add. Cold air is denser at the same altitude. It gets much colder and less dense with altitude. Asus Sabertooth P67 Motherboard 2600k CPU, 16 gig DDR3, 1600. Samsung 830, 256 gig hard drive, GTX780 Video Card, Warthog Hotas, Razer Mamba mouse. Saitek Combat Rudder Pedals. Trackir 5, Verizon FIOS 25Meg Up/Down
Flim Posted March 11, 2013 Posted March 11, 2013 You will have better performance in cold weather compared to hot... Engines like colder air as well...
DieHard Posted March 11, 2013 Posted March 11, 2013 (edited) Altitude ? Via WWII era prop aircraft performance specs at various altitudes I would imagine, if the same is modeled in DCS/World or FC3, performance will vary at various altitudes, given the same aircraft type setup to compare it to. The test pilots and test engineer pilots, in the day, would try to experiment with every feasible situation before handing it over to the regular pilots as safety issues and operating limits. The WWII era sim/game Aces High: Home with drop-down tabs: http://www.hitechcreations.com/ Plane specs with some quantitative graphs as to speed and climb rates: http://www.hitechcreations.com/wiki/index.php/Aircraft_of_Aces_High_II Plane Performances comparing one type against another: http://www.hitechcreations.com/component/option,com_ahplaneperf/Itemid,221/view,ahplaneperf/ Similar specs: http://members.shaw.ca/soda_p/models.htm Wiki: http://www.hitechcreations.com/wiki/index.php/Main_Page A guy to Aces High that has a squad that flies the F4U is who got me interested in the Ka-50 as he also frequents here or used to. I quit Aces High after 5 years at $15 per month and only hang out to DCS/Lock On and sometimes to FSX. The big issue with dog-fighting in Aces High is very dependent on ISP upload/download broadband speed. Edited March 11, 2013 by DieHard [sIGPIC][/sIGPIC]
Exorcet Posted March 11, 2013 Posted March 11, 2013 Cold air means slower speed of sound, and compressibility is an issue for the Su-25. Awaiting: DCS F-15C Win 10 i5-9600KF 4.6 GHz 64 GB RAM RTX2080Ti 11GB -- Win 7 64 i5-6600K 3.6 GHz 32 GB RAM GTX970 4GB -- A-10C, F-5E, Su-27, F-15C, F-14B, F-16C missions in User Files
Weta43 Posted March 13, 2013 Posted March 13, 2013 if the same is modeled in DCS/World or FC3, performance will vary at various altitudes, given the same aircraft type setup to compare it to. It is, that's why I asked... Cheers.
RIPTIDE Posted March 14, 2013 Posted March 14, 2013 I am assuming it has to do with altitude.. The "problem-mission" takes place within large mountain-valleys mostly. since it's rather difficult to judge altitude in mountainous area... bottom mountain-valley level doesnt quite feel "much" higher, than regular plains areas. And even flying a bit further up, while turning back onto targets over the mountains at around 2-3000m (barometric?) altitude, it somehow feels exceptionally worse than flying at around 2-3k altitude over flat terrain AND around 20 degrees Celsius higher temperature on the "better/warmer" map. I don't think the SU25-T normally uses radar altitude, right.. its barometric? What I thought about is possibly turbulences/wind around mountains.. but I dont think that is actually modeled in DCS, is it? Osram. I think you should be more specific as to what valleys. Some of the flats you might be talking about are already 400-800m Above Sea level, around Tblisi for example. Then there's the raised valleys. The Valley that runs into the Roki Tunnel starts at about 1,000 metres and ends up about 1,600 metres, just as an example. Now if you're trying to achieve a hard deck of say, 4,500 metres AGL... in a Su-25T loaded to the gills, that extra 1,600, on top of already 4,500 is substantial. So my advice to you is to carry appropriate payloads and fuel, more suitable to high altitude valley manoeuvring. As for the Altitude, the 25T uses Radar AND Baro. Radar works to 1,500. [sIGPIC][/sIGPIC]
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