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Guest higge

Altitude and speed question.

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Hello all.I have this weird problem I can't solve.When I make my flightplan comp seems to calculate speed and altitude itself as it should, but after takeoff autopilot increases altitude very fast about 4500ft per minute... And decreases speed to 150kts.Im getting a-floor at same time. I know it might be something in my end but cant figure that out. I always use loadeditor and fuelplanner, FMC programmed within manual but still..Thanks in advance Edit.I'm using Airbus Pro series in FS9

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Hello all,I would also like to see an answer to this question. The aircraft in my simulator never climbs at such a steep angle to bleed airspeed down to the a-floor limits, but it surely starts climbing at about 3500-4500 fpm. This is also its response to flightlevel changes during flight.I would like to know if it is a realistic implementation of the real airplane. After studying the manual of the real thing, it is correct that that the autopilot during climb tries to keep up airspeed settings using pitch, so the response of the PSS A340 is correct, but since 4500fpm is not a very comfortable climb for the passengers, I would like to know if that is what happens in the real airbus.Thanks a lot in advance,Mike

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One of the most crucial things in the initial climb is to make sure that you hold V2+10. One way of assisting with this is to make sure the trim is set to -2.0UP (use the home and end keys and watch the F/CTRL page on the lower ECAM). You thus hold the speed indicated by the magenta triangle on the PFD. When you activate the autopilot there is then no sharp pitch up. It is then a good idea to control the rate of climb using the V/S knob and make sure you are not going above about 2300 fpm.But what happens with a lot of pilots in the PSS on the simulator is that they allow the speed to shoot through V2+10 to quite a lot higher. When they then engage the autopilot the computers command a sharp pitch up in order to bring the speed back to V2+10. But such a sharp pitch up at 4..5..6000 fpm can really cause the IAS to bleed off quickly leading to the A-FLOOR. This would not happen in the real world version where the protections would prevent it.I am not saying this is definitely what is happening in both your cases but it sounds like it might be.

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Thank you, I try this tonight.Still remains one thing. When its climbing abit fast and tries to reach right altitude, plane doesn't stop climbing etc FL250 as it is in flightplan. It goes up until I manually stop it. And when it should descend it doesn't. Is it something about programming or is it just the feature?Thank you in advance,Higge

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Once you have entered the flight level in the FCU you then need to press (left click) the alt knob for managed mode or pull (right click it) for selected mode. As an explanation, basically managed mode follows the flight plan, alt constraints, speed constraionts etc put into the MCDU. Selected mode gives you the control for the short term and you would use selected speed, heading or alt (or a combination of these) if yu were , for examle, givcen radar vectors by ATC which took you away from the flight plan programmed into the MCDU. Being able to use managed adn seleced modes appropriatel is key to a successful flight with the Airbus.Rob Elliott, EGPE InvernessPSS Airbus Support andAirbus Fleet Training Captain, British Airways Virtual airbus@speedbirdonline.co.ukhttp://www.speedbirdonline.co.uk/airbus.htmlhttp://www.bavirtual.co.uk

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