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Guest venquessa

V Speeds, autopilot, approach.

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I've been getting used to the airbus but I am having a number of problems.On take off, all the tutorials I have read thus far suggest flaps 3. This seems a very high flap angle for take off. Setting the V speeds with right click, and using FLX power, some of the models lift off before rotation, the smaller ones, sit there, even with full stick back well beyond V2, you need to apply trim to get off the ground and the nose rockets up sharply risking a tail strike when you do this.So, are there any golden rules about what flap to select and what trim setting (is there a guage) to use for take off?On approach I have 2 problems. The approach phase auto speeds seem like a nice idea, but I find them very pitch happy. Coming in off a 250 knots arrival, I engage the Approach phase, the aircraft slows to clean speed, with about a 8 degree nose up. Going to flap 1 initially lowers the nose, to normal, but the plane slows again and the nose rises to 8 to 10 degrees. This repeats until you get to glideslope capture and full flap. If you have to do any tight turns to capture the ILS (like I recently tried Innsbruck LOWI east approach), the pitch can rise up to 20 degrees and the autothrottle is lazy enough to even risk a stall!It seems the V speeds are calibrated for a constant glideslope like descent, but in level flight they are about 5 to 10 knots too slow.The other problem is with the AP, in managed heading hold, LOC or APP armed. It starts turning wildly off the LOC. It did a full 360 turn on me approaching Tenerife this evening and earlier it turned me for the mountains coming into Innsbruck in zero vis. I couldn't see any reason for it and it ignored any heading inputs until I discoed the AP and FD and reset them again.Paul

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Paul:I am using flaps 2 on all the airbusses with good results. As for takeoff, I'm using these trim settings:A 319 Up -3.2A 320 Up -2.2A 340 Up -3.2I doubt that these are realistic, but they seem to do the trick. In order to avoid the nose-up during approach, I added -as suggested on this forum- a lift_scalar line to my respective aircraft cfg. Do a search and you'll find the fix.ricardo

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Flaps 1+F is a normal config for takeoff. The vSpeeds for this and the other flap settings depending on takeof weight can be found at the BAV Speedbirdonline site in my address below. In most cases 1+F will be fine, but if you have a short runway, or perhaps are very light, flaps 3 is common. Flaps 2 is far less common in my experience.For trim, I use -2.0UP which seems to work OK.If the nose is too high it does sound like a lift_scalar issue in the aircraft. cfg flaps.0 section as Ricardo said. For the A319 and A320 try 1.42 and for the A321 0.926. That should help.If when selecting LOC the aircraft turns away from where it should go (to 000 degrees?) there are two things to check: 1) that on the default aircraft, the Boeing 737 for example, the GPS/NAV is set to NAV, and 2) that you have the correct ILS freq at LSK3L in the RAD NAV page of the MCDU.

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Paul:Just to clarify: the fixes I suggested are fixes I got from other users, "Airbus Training captain" being one of them.Thanks, Rob, for all the helpful posts you've made here.ricardo

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Thanks for that. I'll make the change to the aircraft.cfg you suggest.Yesterday while having a flight I changed the approach technique so that I would not be in level flight, left the APPR phase until I was very near the G/S and so as I brought the flaps out, i was already descending towards G/s capture. It's too easy to end up chasing the G/S down though. The other option that worked was using manual speed settings.Paul

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