egaRim Posted January 9, 2007 Share Posted January 9, 2007 Hi there, yesterday a squad mate and me encountered again the problem with the Frogfoot's HSI: Sometimes (but not always) the HSI would not align and show wrong headings after starting up the engines. I could not find any information in the sims documentation nor in the forums. Is there a certain start up procedure one has to obey to prevent the misalignment? Or is it bug? I usally activate electrical power, wait for 15-30 seconds and then initiate engine 1 and 2 in sequence. I would appreciate any comments from Su-25 drivers :) Thanks in advance. Link to comment Share on other sites More sharing options...
Prophet Posted January 9, 2007 Share Posted January 9, 2007 Make sure you wait until the HSI stops spinning before starting the engines. Other than that, I dont know. Link to comment Share on other sites More sharing options...
VapoR Posted January 9, 2007 Share Posted January 9, 2007 Make sure you wait until the HSI stops spinning before starting the engines. Precisely. Link to comment Share on other sites More sharing options...
Force_Feedback Posted January 9, 2007 Share Posted January 9, 2007 wait more than 3 minutes, patient my young padawan you must be Creedence Clearwater Revival:worthy: Link to comment Share on other sites More sharing options...
Jay Posted January 9, 2007 Share Posted January 9, 2007 Yep, sometimes 30 sec. is enough but wait 'till it stops and you're ready to go for engine start then. You can fill that time with other procedures (setting up your WCS, calling tower for runway heading, turning on nav lights and IR jammer etc.). [sIGPIC][/sIGPIC] AMD Athlon 64 3000+ (Venice, OC to 2,66 GHz), MSI K8N Neo Platinum (nForce 3 250 Gb), 1,5 GB Corsair PC-3200 RAM, GeForce 7800GS 256 MB VGA (G71, OC to 535/1550 MHz, ForceWare 84.21), 2 x 300 GB Maxtor DiamondMax 10 SATA HDD (RAID 0), SB Audigy 2 ZS, 480W Thermaltake PurePower TWV PSU, Win XP SP2, MS SideWinder Precision 2, Belkin Nostromo n52 SpeedPad, HP L1902 Link to comment Share on other sites More sharing options...
MBot Posted January 9, 2007 Share Posted January 9, 2007 I experienced similar things. I usualy wait 10-20 seconds until the HSI has setteled on the correct heading before starting the engines, only to discover the HSI being missaligned after take-off sometimes. But most often the HSI works perfect with 20 seconds alignement. I can't see a pattern. Link to comment Share on other sites More sharing options...
egaRim Posted January 9, 2007 Author Share Posted January 9, 2007 You can fill that time with other procedures (setting up your WCS, calling tower for runway heading, turning on nav lights and IR jammer etc.). I can do all these procedures in less than 30 seconds ;) I usally take a very close look at the HSI before I run up engines. I often don't see any movement but still experience those misalignment problems afterwards. I might need more patience, though... :music_whistling: Link to comment Share on other sites More sharing options...
Guest IguanaKing Posted January 9, 2007 Share Posted January 9, 2007 Just remember that the INS and the HSI aren't the same thing. ;) The HSI card can be driven by either a DG/flux detector or AHRS/flux detector combination, but not the INS. This misalignment of the HSI happens occasionally IRL with a DG/flux detector combination, but its usually easily corrected by putting the HSI in "free" mode, slewing the card about 90 degrees,and then putting it back in "slave" mode. I'm not sure if LOMAC allows you to do that though, and I'm not sure if the Su-25T is modelled with a DG or AHRS. AHRS is slower to stabilize, but its usually not subject to alignment problems...provided the aircraft is kept in one spot during alignment. Heh...sorry...I know this probably doesn't help. ;) Link to comment Share on other sites More sharing options...
crusty1606687734 Posted January 9, 2007 Share Posted January 9, 2007 Just remember that the INS and the HSI aren't the same thing. ;) The HSI card can be driven by either a DG/flux detector or AHRS/flux detector combination, but not the INS. This misalignment of the HSI happens occasionally IRL with a DG/flux detector combination, but its usually easily corrected by putting the HSI in "free" mode, slewing the card about 90 degrees,and then putting it back in "slave" mode. I'm not sure if LOMAC allows you to do that though, and I'm not sure if the Su-25T is modelled with a DG or AHRS. AHRS is slower to stabilize, but its usually not subject to alignment problems...provided the aircraft is kept in one spot during alignment. Heh...sorry...I know this probably doesn't help. ;) No, Lomac doesn`t allow you to turn your OBS knob on HSI. Hopefully in BS... There always good old magnetic compass if everything else craps out. Just check the correction table for possible interference errors from elec. system, airframe, etc. ... I could swear I saw the table somewhere in the T frog... have to check again. Link to comment Share on other sites More sharing options...
Guest IguanaKing Posted January 9, 2007 Share Posted January 9, 2007 No, Lomac doesn`t allow you to turn your OBS knob on HSI. Hopefully in BS... There always good old magnetic compass if everything else craps out. Just check the correction table for possible interference errors from elec. system, airframe, etc. ... I could swear I saw the table somewhere in the T frog... have to check again. Yup, I knew about that already. :) The OBS (or CRS in the case of an HSI) and slewing the card are two different things though. ;) Link to comment Share on other sites More sharing options...
egaRim Posted January 10, 2007 Author Share Posted January 10, 2007 Well thanks for these background facts... nice to know what you could do IRL... that's why we like simming, isn't it? ;) I was talking about the vanilla frogfoot. Could not find a auxiliary compass yet. Is it hidden somewhere? Link to comment Share on other sites More sharing options...
Guest IguanaKing Posted January 10, 2007 Share Posted January 10, 2007 Neither frog has a wet compass. Link to comment Share on other sites More sharing options...
Weta43 Posted January 10, 2007 Share Posted January 10, 2007 They do take a while to spin up (20 - 30 sec usually gets them stable though), but even then sometimes they don't find the correct course. If you wait till they're stable, then switch to any other nav (2,7 etc) mode & back to '1' they'll line up. I now always change to another mode & back before requesting a runway from the tower when in the 25 & 25T Cheers. Link to comment Share on other sites More sharing options...
bogusheadbox Posted January 10, 2007 Share Posted January 10, 2007 Hmmm I am not sure i agree with you guys. The frog is my craft of choice and my start up is this. start left engine, Start right engine Turn on electrics Close canopy. Set lights Set flaps. Call for taxi clearance. Taxi when engines have spooled down to ground idle. (by that time all navigation instruments are aligned). Maybe its the starting of engines after turning on electrics that causes a problem. ????? Link to comment Share on other sites More sharing options...
ViperVJG73 Posted January 10, 2007 Share Posted January 10, 2007 Maybe its the starting of engines after turning on electrics that causes a problem. ????? LOL .In real they have to first switch on electrics before you start engines. Power off: no working fuel pump, no working engine starter and no working ignition! :) Best Regards Viper System: Intel Core i7-4790, 3,6GHz, 16GB RAM, 128GB SSD, 2TB HDD, NVIDIA GeForce GTX 960 2GB GDDR5, TM HOTAS Warthog;(MSFFB2 for testing); TrackIR4 +Track Clip Pro; Windows 10 Pro. Link to comment Share on other sites More sharing options...
Guest IguanaKing Posted January 10, 2007 Share Posted January 10, 2007 Actually, that depends on which electrical system you are talking about. ;) Its true that the engines will not start with the main bus off, but you don't need the avionics bus on in order to start the engines. Then, it just becomes a matter of how the aircraft was wired. Some put the DG/AHRS and HSI on the main bus, others put it on the avionics bus. In general practice, its not the best idea to turn the avionics bus on until your engines are both started and the generators are on-line. :) Link to comment Share on other sites More sharing options...
Stealth_HR Posted January 10, 2007 Share Posted January 10, 2007 IK, I remember you posting about that some time ago, had to do something with frying the radio (among other things) in case of a voltage spike. ..right? :music_whistling: [sIGPIC][/sIGPIC] Real men fly ground attack :pilotfly: where EVERYTHING wants a piece of you :D Link to comment Share on other sites More sharing options...
Guest IguanaKing Posted January 11, 2007 Share Posted January 11, 2007 Right on, Stealth. :thumbup: Link to comment Share on other sites More sharing options...
Recommended Posts