D-Scythe Posted June 17, 2006 Posted June 17, 2006 That was from testing LOMAC F-15. Yeah...I know...? Maybe I should refer to the F-15C in LOMAC as the F-15LO :p
hitman Posted June 17, 2006 Posted June 17, 2006 Yeah...I know...? Maybe I should refer to the F-15C in LOMAC as the F-15LO :p Mystery solved!! Now can the F-15LO be upgraded to the F-15c?
Guest IguanaKing Posted June 17, 2006 Posted June 17, 2006 Oh well...keep up the analysis guys. I guess nobody mentioned air temperature. :music_whistling:
Rhen Posted June 18, 2006 Posted June 18, 2006 We did mention air temp :thumbup: The engines would not necessarily be trimmed to 102% or VMax used since this would increase the workload on the maintainers and cause a bunch of NDIs (non-destructive inspections) or engine/airframe teardowns, thus taking that bird/engine out of service more rapidly than regular use. At 102% trim the engines require inspection after 100hrs - I think. That's from engine start to stop. So, you figure if it's trimmed at a FOL, then, the aircraft trip turns every day at a 5.0 sortie duration, then after 6 days & 2 sorties, then the aircraft/engines would be out of commission until NDI complete. Now if the war effort requires it and there's more airframes/replacement engines, then the war tempo would dictate 102% trim. Those falcon numbers seem low for SE thrust. Perhaps GW, drag, or some other ephemeral number was approximated, necessitating lower thrust settings.
Spins321 Posted June 21, 2006 Posted June 21, 2006 Hey, guys, Sorry to butt into the conversation late. I work with an F15 squadron ANG squadron, and know many of the pilots. We fly both F15A's and F15C's (currently). I'm also working on F15's for MS Flightsim, and we've got pilots from each version of the F15 (from A to E) helping us with verification, including a former test pilot. Now, I'm not a math guy, I'm a 3D dude, but having dug into the TO's, here are some generalizations you guys probably know about. 1. F15 top speed is borked. The statement about the wall is correct, that's a vmax issue with the engines and some airframe components. Not many people know, but an F15A with (I believe) 229 engines was flown to Mach 3+ (canopy vmax was exceeded) over Edwards a number of years ago. The canopy melted and warped in many areas. 2. Wing loading and turn performance is way off. Turn performance charts are really important. I'll see if my FM guy would be willing to post up some real turn performance numbers. Part of the problem may be in how they tried to model the Pitch Ratio of the hydromechanical system. Here's a general excerpt of how it works: The Pitch Ratio is scheduled to give you about the same stick travel per G throughout the flight envelope. The ratio is about 4.25 lb/g. It is scheduled by Mach number and altitude and does a rather good job; however, it won't quite cover the full range of aircraft and stabilator power and there is some scatter of the Fs/g, i.e., some mild increase in sensitivity during low altitude/high speed flight, and some decrease in sensitivity at low speeds. Pitch Trim Compensator- This basically changes how control surfaces are deployed when something disturbs the aircraft in pitch, ie.: speed brakes, transonic trim changes, flap extension, etc. So, the stabs need to trim automatically, and their deployment rates need to change to maintain the 4.25 lb/g schedule. Now, from our tests in lomac, it appears they tried to model this system, and it's impacting the flightmodel. When we compared the turn rate to our current model, it just seemed as if the stick was getting in the way, in that at certain areas of the turn the stick was losing authority (this was all flown at half stick rates). Sorry for the geekiness, there's just one more thing I wanted to point out. 3. Keep in mind that the F15A, even with -100's, is more maneuverable than the F15C. The F15A has a faster nose, and can crank tighter than a C. The C has a ballast in the nose because of the extra fuel weight when they added the extra fuel cells in the centerline and in the wing. This was done to bring the CG back to it's original configuration in the A. Thus, this created a slower nose. Now, I say slower, but the F15C's nose in lomac feels like it's anchored! Again, I'll see if I can have my FM guy post some real numbers. Oh, and this is just a gripe... FIX THE EYEPOINT!!! No F15 driver would ever be able to work with his body scrunched in the pit like that! hehe. A more realistic view would be to atleast have the HUD centered on the center of the monitor.. And radar/nav avionics don't match any F15 version it seems. Jamal 1
GGTharos Posted June 21, 2006 Posted June 21, 2006 ... Thanks Spins, very good info! My 2c just to explain the LOMAC situation as I understand it: IIRC the pit isn't going to be touched for quite a while, nor the FM To explain: ED doesn't want to touch the current FM because they wish to transition everything to AFM. If you have data that will help them model AFM well, and you are willing to share, PLEASE do! About the pit and avionics: Again, ED has developed 3D pit technology as well as a system and avionics model to go with this. So I think they would rather transition to this as opposed to fixing the current model. In other words, it'll all happen, but it won't happen for a while :( [sIGPIC][/sIGPIC] Reminder: SAM = Speed Bump :D I used to play flight sims like you, but then I took a slammer to the knee - Yoda
Pilotasso Posted June 21, 2006 Posted June 21, 2006 Interesting post SPins. And welcome to the forums. Been flying with you for a while with JJ online. That mach 3 test is realy stunning news to me. But I bet appart from the cocpit, the plane has suffered stress to other components that if those speeds were to be reached routinely the plane would be scrapped in a fraction of its normal service life. About the manueverability, I dont complain much. Theres bigger fish to fry with the missiles PK against the ground (they work decently looking up though). I only find it a bit more sluguish at high altitude than it should be, apart from that I wouldnt know how much far it is from the real thing. I've never flown in F-15's (though I have a future Viper pilot in my family). I managed to get to mach 2.35 wich compared to the real worlds mach 2.5 is more than I can say for other games. In early F4 variants I could barely reach mach 1.6 in the F-16. LOMAC's F-15 does accelerate in the vertical but with clean config and 30% fuel about to 4000 feet only. With a tank and 8 missiles I can mantain speed at a climb angle of about 30º untill about 15000 feet at wich time I need to reduce to 25º. And thats sarting the climb at mach 0.9 and trying to maintain it. I undrstand that this is the speed at wich real aircraft do their optimized climb rates. Would it possible to fix the F-15 for BS? is it easy achievable? Should this mean all the other aircraft should be fixed in the same extent? .
Spins321 Posted June 21, 2006 Posted June 21, 2006 Woops, made a mistake guys, The F15 high speed test was to Mach 2.8 with engines trimmed to 104-106%. Forget that Mach 3+ nonsense :) And, greetings Pilotasso! Hope to catch you online again soon! Jamal
Frodo13 Posted June 21, 2006 Posted June 21, 2006 Woops, made a mistake guys, The F15 high speed test was to Mach 2.8 with engines trimmed to 104-106%. Forget that Mach 3+ nonsense :) And, greetings Pilotasso! Hope to catch you online again soon! Jamal Nice correction Jamal! Actually the F15A has done several a lot of high speed test runs then was replaced by the Charlie from conversations with our consultant. There was also one or two Charlie(s) with the -229 engines that unofficially broke the "World Climb Record" set by the SU-27 several times. There are severl test aircraft (15/16) at EDW that have the F119 installed to keep up with the F22 in acceleration tests. Anyhow... As Rhen pointed out, engine trim is lowered for costs and maintainability and the VMAX switch (98% RPM) is wired shut. The question is what engine trim is ED modeling? If one was to go by their engine gauges to find the engine trim their maximum readings are: MIL 100%, AB 110% which are completely inaccurate. Given the indication of 100% at MIL does that mean that they tried modeling at engine trim at 100%? They only to way to tell it do so some tests in-game and compare how close it is to the 102% figures and verify that the results over past the 97% figures. However, in real life, the F15 engines are trimmed to 96% so the thrust is lower than you think. Turn performance. I hope some of you aren't expecting the same performance at lower altitudes. Around FL300, you must fly at least M1.2+ to sustain nearly 4G whereas at SL, you could do this around M0.35-0.4 As Jamal mentioned, the stick gains aren't exactly perfect. There are things you can do in the real Eagle from what our consultants tell us that you can't do in LOMAC. Ps... Can someone get some aerodynamic and propulsion data from LOMAC? So one could compute the Psub to compare to the real thing? Airshows... Please STOP using your MKI to validate what see at airshows to validate what is in LOMAC. There's a big difference because you have no idea what the configuration (weight, DI, fuel state) and weather these planes are flying at. These planes are light and not in operational 'war' mode. Too many ppl go by what they see too much. Let me give you an example: F18 doing a High alpha pass Most people think the following: doing at least 45-50 Degress of AOA! In reality... He's only doing 25 Alphas around 120 KIAS, he has to pull the nose up to maintain LEVEL FLIGHT! Julian aka "Jewels 201"
GGTharos Posted June 21, 2006 Posted June 21, 2006 Would it possible to fix the F-15 for BS? is it easy achievable? Should this mean all the other aircraft should be fixed in the same extent? As I said, I don't think they'll touch any of the fighters at all for BS ... priority is given to the Ka-50 alone (but this should be no surprise) [sIGPIC][/sIGPIC] Reminder: SAM = Speed Bump :D I used to play flight sims like you, but then I took a slammer to the knee - Yoda
S77th-GOYA Posted June 21, 2006 Posted June 21, 2006 Was Mach 2.8 with a combat ready a/c? Meaning, not the Streak Eagle or some other similarly prepared plane. Also, does anyone have real world data to compare to the in-game speeds of the MiG? It's much faster than commonly published real world figures. Pilotasso, I haven't been able to get the 15 to accelerate vertically at all. There was some carry over horizontal acceleration during pull up, but once vertical deceleration begins immediately. It's as if the 15 is modelled too heavy with too much lift. As for speeds, the in-game 15 exceeds the real world 15 through most of the commonly flown altitude range, but suffers from wallowing at higher altitudes when IAS should be high enough for good maneuverability. Does anyone have data re: real world F-15 horizontal acceleration?
Frodo13 Posted June 21, 2006 Posted June 21, 2006 Goya, All those high Mach runs are configured with the plane 'naked/clean'. As for data, you give cite me the data results in game provided you list the fuel state, altitude, starting - ending speed and I can looking in my DB. I haven't touched LOMAC in awhile but did they ever correct the airspeed bar from TAS to IAS/CAS? I know in the past, I have been able to get the F-15 to accelerate verticaly for a short stint when I was under 5.0K of fuel and altitudes under FL100.
Pilotasso Posted June 21, 2006 Posted June 21, 2006 heres a track I made for 1.12a F-15 flight model. Vertical flight perfomance Max speed maximum sustained altitude at supersonic speed. Deadstick range ;) .
Shaman Posted June 21, 2006 Posted June 21, 2006 *cough* F-15C needs new 3D model, *cough sorry I just had to whine again about flyable 3D models ;) Original poster complained about lack of data-link. As far I know it is realistic on this version of aircraft and been discussed enough times. Also I'd like its arestor hook to be usable. So f.e. airport you taken off from should be by default equipped with those emergency lines you can use. (we could call them using the radio|comms menu). And one thing that bugs me most with F-15. Why the hell can't we switch ILS to diffrent airport! 51PVO Founding member (DEC2007-) 100KIAP Founding member (DEC2018-) :: Shaman aka [100☭] Shamansky tail# 44 or 444 [sIGPIC][/sIGPIC] 100KIAP Regiment Early Warning & Control officer
Pilotasso Posted June 21, 2006 Posted June 21, 2006 *cough* F-15C needs new 3D model, *cough sorry I just had to whine again about flyable 3D models ;) Original poster complained about lack of data-link. As far I know it is realistic on this version of aircraft and been discussed enough times. Also I'd like its arestor hook to be usable. So f.e. airport you taken off from should be by default equipped with those emergency lines you can use. (we could call them using the radio|comms menu). And one thing that bugs me most with F-15. Why the hell can't we switch ILS to diffrent airport! When JTIDS was first introduced on the F-15, the mainstay of the eastern block fighters were mig-21's armed with rear aspect atol's. ;) It was the year 1984 and even F-15A's were retrofited. SO your using a bit of imagination thinking that its realistic for 1990's aircraft not to have it. 1 .
169th_Crusty Posted June 21, 2006 Posted June 21, 2006 ...He's only doing 25 Alphas around 120 KIAS, he has to pull the nose up to maintain LEVEL FLIGHT!... Actually, I`ve heard of Hornets "walking" on occasions at... 95KIAS - not at the airshows though. :(
GGTharos Posted June 21, 2006 Posted June 21, 2006 Was Mach 2.8 with a combat ready a/c? Meaning, not the Streak Eagle or some other similarly prepared plane. Also, does anyone have real world data to compare to the in-game speeds of the MiG? It's much faster than commonly published real world figures. This may actually -not- be a max speed issue though ... it could be a part and engine trim issue -or- fuel, and the migs tend to be famous enough about their afterburners cutting their legs down quite short. [sIGPIC][/sIGPIC] Reminder: SAM = Speed Bump :D I used to play flight sims like you, but then I took a slammer to the knee - Yoda
Rhen Posted June 21, 2006 Posted June 21, 2006 They're right about the F-15s ability to turn and burn. In LOMAC, it's a pig, but then again, it's possible to hang with a MiG-29, in LOMAC in a BFM engagement.... (looks both ways)... (I'll probably get killed by my buds for this but...)... but with regards to pure aircraft performance, the Eagle needs a better pilot to hang with a Viper or Fulcrum in a guns fight. I don't know how many vipers I've killed "virtually" using ACMI IRL in a GUNS fight (tracking kills with the hud tape to prove it), but if you can get a kill on a F-16 after they've been practicing air-to-air for a few weeks, then you've done something SWEET! Savor the taste.8) Mind you, we still peel them like grapes when using a slammer, even WVR.:thumbup:
Frodo13 Posted June 21, 2006 Posted June 21, 2006 Actually, I`ve heard of Hornets "walking" on occasions at... 95KIAS - not at the airshows though. :( If you aren't on the airshow circuit the TAC maneuvers are different. Big difference. Airshow maneuvers are deemed safe for the crowd and the FAA. Go higher and away from the populated areas, things change. These demos are a glimpse of what the plane can do 'safely' in front of the audience.
Cobra360 Posted June 21, 2006 Posted June 21, 2006 If you aren't on the airshow circuit the TAC maneuvers are different. Big difference. Airshow maneuvers are deemed safe for the crowd and the FAA. Go higher and away from the populated areas, things change. These demos are a glimpse of what the plane can do 'safely' in front of the audience. That must make the F-15 a very dangerous fighter then,:P
Shaman Posted June 21, 2006 Posted June 21, 2006 When JTIDS was first introduced on the F-15, the mainstay of the eastern block fighters were mig-21's armed with rear aspect atol's. ;) It was the year 1984 and even F-15A's were retrofited. SO your using a bit of imagination thinking that its realistic for 1990's aircraft not to have it. I didn't say what's realistic or what's not. Jest few tester joints had it. That's it. Cs weren't upgraded with it on wider scale. The plane in the game resembles the version which was not upgraded with datalink. So, sorry, dream on. Better luck maybe in Fightershmops. :lol: 51PVO Founding member (DEC2007-) 100KIAP Founding member (DEC2018-) :: Shaman aka [100☭] Shamansky tail# 44 or 444 [sIGPIC][/sIGPIC] 100KIAP Regiment Early Warning & Control officer
GGTharos Posted June 21, 2006 Posted June 21, 2006 F-15 had -some- form of Datalink. JTIDS was just reportedly held back, which if true, effectively puts the dlink at about the same level as the real flanker's ... JTIDS is a whole new ball game though. [sIGPIC][/sIGPIC] Reminder: SAM = Speed Bump :D I used to play flight sims like you, but then I took a slammer to the knee - Yoda
Force_Feedback Posted June 21, 2006 Posted June 21, 2006 F-15 had -some- form of Datalink. JTIDS was just reportedly held back, which if true, effectively puts the dlink at about the same level as the real flanker's ... JTIDS is a whole new ball game though. Do you really understand how and what the datalink does in the Su-27? Cause I've read the manual, and don't sure yet myself. Guess there is a seperate datalink manual, but eh, where to find it? Creedence Clearwater Revival:worthy:
GGTharos Posted June 21, 2006 Posted June 21, 2006 I -think- teh manual you have should give you a fairly good idea of what it gives you, though IIRC it lacks some very much desired detail :P Also I think it should give you a good idea of the data sources for the DL. [sIGPIC][/sIGPIC] Reminder: SAM = Speed Bump :D I used to play flight sims like you, but then I took a slammer to the knee - Yoda
Cobra360 Posted June 21, 2006 Posted June 21, 2006 About the flight model. There is another flaw. In LO it is impossible to fly with one engine shut down and the other in full AB is a straight line with full opposite rudder deflection. In Steve Davis's Strike Eagle book the test pilots of the F-15E are quoted as stating that 100% opposite rudder deflection was found to be not needed to keep flying straight when flying on one engine in AB and the other dead. It does not say if it is a -220 or -229 powered Eagle. Which would imply and the rudders do not command as much authority as they should in LO.
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