capttrob Posted March 30, 2006 Posted March 30, 2006 Whats the deal with 20-40 degree bearing changes on the TEWS by just rolling the airplane into a bank, with little or no heading change? Also the Air data computer seems to take a hit as well. The Altitude tape on the hud goes haywire when you roll the airplane below about 5000. Is altitude on the HUD supposed to show AGL at all times? I noticed all these things when i first started flying the sim, but with so much to learn in weapons systems, i didnt really pay much attention to it. Flew my first ILS in poor vis today... the nav mode is just a mess....lol. I noticed that you only get ILS needles when the gear is down. I cant imagine a real F-15 dragging the gear on a 15 mile final just so he can intercept the loc.... still a great game... but come on now.. this is basic stuff.. no?
capttrob Posted March 30, 2006 Author Posted March 30, 2006 I paid more attention to this closely today. Its below 3000 and the altimeter tape on the hud goes wacko when you roll into a bank (The analog altimeter works just fine). The heading changes up to 90 degrees as you roll into a 90 degree bank, as well as anything ID'ed on the TEWS spinning up to 90 degrees with your roll. It doesnt start to stabilize till you actually start turning. It seems the code has heading changes matched to degrees of bank angle, then when the nose actually starts to come around it will stabilize.... got a good chuckle out of it. I didnt know a modern fighter like the F-15 had unslaved gyros that also affected ADC.... :D edit: PS, i did get ILS needles without the gear down today, so i dont know what i was seeing before. I guess i just thought it was a gear thing since the needles didnt come up till very close to the runway and once i put the gear down they popped up. I'll have to check distance next time, or perhaps a tester could chime in... :)
Gazehound Posted March 30, 2006 Posted March 30, 2006 I paid more attention to this closely today. Its below 3000 and the altimeter tape on the hud goes wacko when you roll into a bank (The analog altimeter works just fine). What you are seeing is radar altitude. This is measured by emitters/recievers on the planes wings which point straight down hence rolling from level flight produces error. Above 3km the barometric alt takes over as you are too high to get a radar alt measuremnt. In russian planes if radar alt is on you see 'p' next to the numeral in the HUD, IDK about eagles, but I think there is a digital readout of baro alt in there somewhere - if not use the steam gague. With russian RWR you also see a similar thing when you bank the threat seems to circle around you a bit - this is also due to the locations of the recivers on the plane. I use rudder a lot to turn into a threat or to beam since you can keep a lower bank angle and dont turn too far/little (or use heading calculations). VVS504 Red Hammers
Shepski Posted March 30, 2006 Posted March 30, 2006 Below 3000 feet AGL the radar altimeter kicks in on the HUD and will not show a radar altitude when in a steep bank do to not being able to receive the radio wave reflections off the ground so it reverts to a baro altimeter indication until you roll back and the RADALT can indicate properly. I don't see a problem with the heading(tape/DG) doing a 90 degree change when you roll. If the TEWS threat is on your nose, when you roll, there is no strange behaviour but it does appear the more it is offset off your nose... either a bug or maybe the TEWS receivers have a problem when doing a fast roll of knowing where the signal is coming from. ILS needles work fine when approaching the fix at a proper intercept angle.
capttrob Posted March 30, 2006 Author Posted March 30, 2006 LOL.. are you sure these "emitters" are on the wings? I've been flying airplanes for 20 years and never seen a radar altimeter behave like that. Usually the transmitters are somewhere in the fuse and slaved with a gyro. I hardly believe that modern fighter designers put fixed radar altimeter sensors in the wings.... but i guess its a possibility. Same goes for TEWS and heading. Watch your heading tape, it does the same thing in a roll till bank is stabilized and the nose is turning. This is known as gyroscopic precession and is usually dampened by air nozzles (thrusters if you will) in the gyro structure (edit: Hence vacuum pressure for Gyros). It is further dampened and never needs to be "reset" to the compass by use of a slaved gyro in most high performance aircraft and jets. If you're flying a Cherokee, you'll need to reset your DG (directional gyro) due to precession every once in a while. But at least the "thrusters" inside the gimble keep the thing upright when you bank. The heading tape in this game behaves more like magnetic dip (kinda). IIRC, the mag compass seems to work better than the heading tape when banking, accel, climb, descent. I'll have to look closer at the compass next time. Perhaps thie F-15 gyros act the way they do is because Russian gyros are designed that way and Russians developed this game (or maybe Russians never serviced their gyros and the thruster valves got sticky after a while? lol...jk). But i HIGHLY doubt the F-15 has fixed RA transmitters in the wings and/or unslaved gyros. Im sure Rhen can chime in here... Also, by kicking the rudder only to turn the airplane because of a poor gyro design, is not a way to fly an airplane :)
Shepski Posted March 30, 2006 Posted March 30, 2006 LOL.. are you sure these "emitters" are on the wings? I've been flying airplanes for 20 years and never seen a radar altimeter behave like that. ) It reverts to a baro altimeter indication while in a bank until you roll back and the RADALT can indicate properly... this is the tape scrolling you see. I would think the emitter is on the fuselage.
capttrob Posted March 30, 2006 Author Posted March 30, 2006 ok.. that makes more sense.. thanks Shep. edit: Although the design makes no sense if thats how its really designed IRL, which i doubt is the case. Imagine getting down near DH with 1600 RVR and banking for correction only to see your RA revert to MSL...lol. (But then again, many fighter jocks i have flown with making the transition to airline do use rudder only for loc corrections and need to be taught the right way... so who knows) I read your response after i had responded to Gazehound. Hopefully Rhen can chime in here...
Shepski Posted March 30, 2006 Posted March 30, 2006 ok.. that makes more sense.. thanks Shep. edit: Although the design makes no sense if thats how its really designed IRL, which i doubt is the case. Imagine getting down near DH with 1600 RVR and banking for correction only to see your RA revert to MSL...lol. If you're banking 45 degrees at DH with 1600 RVR then you deserve to die! :) I have no idea if that's how the real Eagle system works.
capttrob Posted March 30, 2006 Author Posted March 30, 2006 It only happens at more than 45 deg? Didnt know that. 45 degrees is not considered "steep". 60 degrees or more is steep (technically ;) ). But you're right, any correction that requires more than 20 that close to the ground is cause for go-around. And my bad on the heading scroll. It doesnt scroll like the TEWS. I just checked it again. The TEWS is mucked up though.... bad. 90 deg bank equals close to 90 bearing change on target. edit: And where is the magnetic DIP!!?!?!?! lol j/k. If you guys put mag dip in this game, thats cause for multiple awards and possibly a date with a supermodel of your choice.
capttrob Posted March 30, 2006 Author Posted March 30, 2006 As for ILS limits. Is it programmed to cover anything like this?
capttrob Posted March 31, 2006 Author Posted March 31, 2006 I did some more checking this morning while flying my bad weather mission i made. Below 1000 feet agl, you can bank at any angle (even roll 360 degrees) and it will remain as RA (will not revert to MSL). Above 3000 was also showing AGL. I was level at 5000 MSL and the HUD tape showed 3500-4500 depending on terrain. Slight banks angles would trigger the HUD to scroll to MSL. So i have no idea what is going on...lol I normally would not notice these things in such detail flying CAVU in LOFC. But i made a mission with the worst weather possible (sliders at extremes for base and thickness with rain) including a MiG29S engagement near the edge of the range envelope for carrying 1 tank with RTB. So i was forced to fly the gauges... The MiG never had a chance...lol Anyone ever thought about making a server mission with poor weather? The FPS does take a pretty good hit, even when VMC on top. So i can imagine its probably not too practical.... although it would be fun to see who can claim their stake when pilot workload increases and return to base without crashing. I think i broke out around 700 agl on final. The runway lights were a little dim, but i downloaded the "bright lights" mod from TDW's website. Havent tried it yet though.... edit for typos
Shepski Posted March 31, 2006 Posted March 31, 2006 I did some more checking this morning while flying my bad weather mission i made. Below 1000 feet agl, you can bank at any angle (even roll 360 degrees) and it will remain as RA (will not revert to MSL). It will still show the RADALT tape but when you bank the altitude caret will move up the tape when it loses the radio signal and give incorrect altitude information. To check it just fly on the deck, 200 feet, and play with bank angles and see what the caret is doing. Above 3000 was also showing AGL. I was level at 5000 MSL and the HUD tape showed 3500-4500 depending on terrain. Slight banks angles would trigger the HUD to scroll to MSL. So i have no idea what is going on...lol Were you flying over high terrain? you may have been at 5000 ASL but you might have been fying over high terrain that was less then 3000 feet below you and it was triggering the RADALT. If you were over high terrain and on the RADALT, steep banks will trigger the ASL reading. Anyone ever thought about making a server mission with poor weather? I have seen server missions with some low lying fog but I think a low overcast would be a lot of fun, especially when playing in the mountains.
capttrob Posted March 31, 2006 Author Posted March 31, 2006 It will still show the RADALT tape but when you bank the altitude caret will move up the tape when it loses the radio signal and give incorrect altitude information. To check it just fly on the deck, 200 feet, and play with bank angles and see what the caret is doing. I'll have to check that. But im sure you're right. I rolled 360 on final when i broke out... 1/4 mile from the runway... about 100 agl down and dirty...didnt die either ;), while watching the HUD tape closely...but i'll check it again... Were you flying over high terrain? you may have been at 5000 ASL but you might have been fying over high terrain that was less then 3000 feet below you and it was triggering the RADALT. If you were over high terrain and on the RADALT, steep banks will trigger the ASL reading. I was flying at 5000 MSL and the HUD tape was showing 3500-4500. So i guess the terrain was fluctuating between 500 and 1500 MSL while enroute. I was at all times above 3000 agl though, which is what we first thought was the altitude where RA was triggered on the HUD. Below 3000 agl, it does take a larger bank angle to trigger "MSL scroll". But as referenced above, 3500-4500 agl on the HUD with 5000 MSL on the baro altimeter shallow banks triggered HUD scroll on the alt tape. edit: Not really sure what the terrain was except for what my instruments were telling me, didnt have charts and i was IMC. I suppose i can cross reference it with waypoint distance and the map when i exit the mission, but thats too much work. F10 doesnt work in my mission settings.. ;) I have seen server missions with some low lying fog but I think a low overcast would be a lot of fun, especially when playing in the mountains. I think it would be too. Seperate the men from the boys... ;) Anyone want to give it a go? Anyone have sectional charts or IFR Lo-Hi's for the area we fly in? yee haaa! (perhaps LOFC already has them with Obstruction clearence altitudes...MOCA, MORA, OROCA... etc?) It will also give us Eagle drivers with our mucked up AMRAAM's a chance against ET's! (assuming the ET's perform they way they are supposed to) edit: I think i may be able to find some NOS online. But i dont think it will cover that area.... i'll take a look sometime....
Shepski Posted March 31, 2006 Posted March 31, 2006 I have WACs and TPCs for the area but haven't got them on the wall since we moved.
capttrob Posted March 31, 2006 Author Posted March 31, 2006 Cool.... TPC??? Terminal Patrol Centers? lol... not familiar with that one, or i just forgot.... Well, if an IFR server gets up and running, and perhaps ED gives us some TACAN and a fully functional HSI (i know, probably asking too much), I'd definitely buy the charts, even if ED made them. It sure would add to the realism of the game and make it more a sim.
capttrob Posted March 31, 2006 Author Posted March 31, 2006 Well, i did some searching online for SW Russia and Europe charts. Couldnt find much unless you pay for it. There used to be an unofficial NOS site that posted outdated charts online, but i cant find it. Perhaps someone that uses FS2004 can find sim charts online for SW Russia.
Shepski Posted March 31, 2006 Posted March 31, 2006 TPC are Tactical Pilotage Charts... 1:500,000 with lots of ground detail.
capttrob Posted March 31, 2006 Author Posted March 31, 2006 TPC are Tactical Pilotage Charts... 1:500,000 with lots of ground detail. Ah-Ha! Yeah, i think i learned something about them in college. Sounds familiar now.... Honestly i havent looked at a sectional (let alone an IFR LO/HI.... shhhhhhh ;) ) for quite some time. FMS with integrated avionics, moving map displays and multiple MFD's is a wonderful thing... :icon_supe However, we do get alot of good use out of our charts come christmas time.... makes for some good wrapping paper... :D i gotta stop using my laptop for typing on forums... edited for typos once again... ;)
Shepski Posted March 31, 2006 Posted March 31, 2006 We don't have those goodies in our machines but we just got Universal FMS with TAWS coming in the near future installed into our old jets.
capttrob Posted March 31, 2006 Author Posted March 31, 2006 Who you fly for Shep? I used to go to CYUL and CYYZ often.... If you're into Rush... here is an awesome rendition of YYZ im sure you'll like... if you havent already seen it... http://www.neilpeart.net/movies/yyz_vid.html greatest percussionist of all time IMO.
Shepski Posted March 31, 2006 Posted March 31, 2006 I fly for Canadian North Airlines... B-737-200 combi and gravel kitted. How about you?
capttrob Posted March 31, 2006 Author Posted March 31, 2006 Used to fly for Independence Air (in the ACA days) based LGA, BOS and CVG.. with HQ and a base at IAD and in ORD (we were the largest carrier out of Washington Dulles). Dornier 328Jet (Delta Connection side). FLYI went out of business Jan 6, 2006. So im on the job hunt. But on the bright side it gives me time to sling shot some 120's and 7's... ;) If you know anyone looking for a pilot with a strong resume, dont hesitate to PM me :) Im also highly considering a career as a consultant in the flight sim world. I'd actually prefer it over going back into "The industry". Im sure you understand.... Gotta love those straight pipes on the -200 though. I have a few friends at DL flying the 200. They absolutely love it. Although i havent seen them in a while so i dont even know if they are furloughed or what. Or even if DL still has the -200's.
S77th-konkussion Posted April 1, 2006 Posted April 1, 2006 [Neil Peart]greatest percussionist of all time IMO. Damn skippy. :icon_pray [sIGPIC]http://forums.eagle.ru/attachment.php?attachmentid=43337&d=1287169113[/sIGPIC]
Shepski Posted April 1, 2006 Posted April 1, 2006 Yup... LOVE Rush! A buddy of mine flew RUSH around northern Ontario in a King Air 200 during the Test for Echo tour... has some great stories and memoribelia(sp?) from the trip.
Guest IguanaKing Posted April 1, 2006 Posted April 1, 2006 Not sure if the F-15s radar altimeter antenna is fixed or not, but that TEWS anomaly you're seeing definitely sounds like a bug. But with the radar altimeter antenna, just remember that even the ones with gyro stab have angular limits. ;) They should just give the LOMAC F-15 EGPWS or TAWS capability...then the RADALT can be used as a redundant system. :D
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