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Guest mgalmozzi

V speeds and V bugs on ASI

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I noticed a quite significant difference between the Vbugs calulated by the ASI and those published by Omykron in his performance charts reference file.Although I don't have experience on 732 it looks to me that Omykron values could be the right ones, cause the ASI's look a little bit too high for this type of aircraft.I would like to know if it's a reported bug or something wrong with my gauge and if there's any chance to modify the gauge setting.FYI my FS is setup on LBS unit and I modify my payload as required for most of my flights.Best RegardsMichele

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The numbers programmed into the ASI's auto-bugs came straight out of a r/w B732 AFM. I'll need some specifics. I just ran a few checks and the numbers are coming up good.RegardsBob ScottATP IMEL Gulfstream II-III-IV-V L-300Santiago de Chile

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Bob,I really like the mode of the ASI bugs are made in the Benoit Gaurant A300 panel.is auto ajustable, and the pilot can adjust each one. this is good, since there is possible (if within charts), do a improved climb take-off.regards

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Thank you Bob for your kind reply, I will just give you some figures to crosscheck and see if I have a problem with my ASI.For weight 110000lbs at sea level and ISA FLAPS15 I get bugs at 137/140/147 on the ASI vs V1=127 VR=128 V2=138 on Omykron performance charts.For same wx and conditions and FLAPS 5 I get 142/144/146 vs 135/137/143.Difference become quite significant at 120000lbs for Flaps 15 143/146/157 vs 134/135/141.Besides the fact that speeds might come from different Individual Runway Tables, if that is not the case, could it be that the speeds modeled in the ASI refer to the less powered engine -9/-9A??? (just my guess).Oh... just for reference... the speeds for landing are quite similar in ASI and Omykron performance, so I really think it's some kind of discrepancy on the takeoff speeds datas only.Looking forward for your kind replyBest RegardsMichele

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I compared the ASI speeds vs the 732 performance (Matt's charts from avsim) and found the ASI speeds high as well. I suspect the V speeds used in tinmouse are improved climb performance.Greg

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OK, I did find some problems with the speeds at flap settings other than 5 for takeoff. I just re-wrote the whole autobug section, and also added clickspots for manual adjustment of the bugs as Gustavo suggests. The autobugs will now set basic speeds...adjustments for pressure/temp/winds will have to be done manually.CheersBob ScottATP IMEL Gulfstream II-III-IV-V L-300Santiago de Chile

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Great! I'm sure the manual adjustment will be much apreciated by those who have the luck of holding r/w performance charts; anybody willing to share a r/w aom??? I can trade with a B727-200ADV one eventually.Where could I download the corrected asi gauge? Will we have to wait for next patch file?Thanks a lot and keep up the good work.MicheleATP A320F/O

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Michele, here goes the RWY Analisys for Take-off at SBIL/IOS - IlheusTake-off Analysis SBIL/IOS 1577m - QNH 1013,2(29.92) Elevation - 15ftRwy 11/29 Flaps 15 Bleeds On OAT EPR Maximum Take-off Weight Vspeeds44 2.00 93,5 (F) 15/16/2342 2.02 94,9 (F) 16/17/2440 2.04 96,4 (F) 17/18/2538 2.06 97,8 (F) 18/19/2636 2.08 99,2 (F) 18/20/2734 2.10 100,7 (F) 19/20/2832 2.12 102,1 (F) 20/22/2930 2.14 103,5 (F) 21/23/3028 2.15 105,0 (F) 22/25/3126 2.15 105,2 (F) 22/25/3124 2.15 105,4 (F) 22/25/3122 2.15 105,6 (F) 22/25/3120 2.15 105,8 (F) 22/25/3118 2.15 106,0 (F) 22/25/31(F) Field Limit(T) Tire speed limit(*) Obstacle limit© Climb LimitWeights - (1000)PoundsSpeeds - 100+Bleeds off Correction - +3% at MTOWValues only for JT8D-17 Engines

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The new ASI is part of V1.1, coming soon...RegardsBob ScottATP IMEL Gulfstream II-III-IV-V L-300Santiago de Chile

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Thanks a lot for this rwy chart extract.I see it doesnt require such t/o distance as I thought it would from the flight dynamics.I will run some tests with these figures and let you have a feedback eventually.Best RegardsMichele

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