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Michael2

Approach attitude

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Does anyone else think that at reference speed, or really any speed the flight control system feels appropriate for a given flap setting, the pitch attitude necessary to maintain the glide slope is too high? I find myself at times with as much as 10' pitch during an automated approach and am crossing the threshold with more nose up pitch than would seem reasonable even after the flare. I confess I do not no at what attitude the real aircraft flies on approach, but what I seeing with the Aerosoft product seems improbable.

The problem is aggravated by the nose pitching down on turning off the autopilot on approach. The momentary nose dive puts me a full dot below the glide slope and in getting back up to it, with the sluggish autothrottle response again results in an excessive nose up attitude.

It seems to me that there is inadequate flap lift in the flight model. Will there be anymore updates to the Airbus X in the near future?

Other aspects of this product are very impressive -- the 3D modeling, the landing lights, textures, frame rates, etc.

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It seems to me that the VAPP speed calculated by the FMC is too low. Most flights end with a VAPP of 129 knots, which is about 8-10 knots less than the speeds calculated by the Wilco and Airsimmer A320s at a similar weight and fuel remaining. Its either that or there is inadequate lift as you say.

Try either dialing in an extra 10 knots on the MCP or use manual thrust on finals. I find the latter to be more stable and approx 140 knots keeps it nicely on the glideslope at the correct pitch. Otherwise, like yourself I end up chasing the needles and landing at a ludicrous nose up attitude.

Also, when disconnecting the AP, resist the urge to manually correct the momentary nose up jolt. It actually corrects itself after a few seconds and the aircraft returns to profile.

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I tend to disengage the AP either before the glideslope, or very soon afterwards i.e. at more than 2,000ft and don't feel there's an issue with the pitch. If you're disengaging at 500ft, I could see how that might get out of shape. I know it shouldn't, but I'd rather do what works than fight against something that doesn't. Not to mention that I find using the AP that much is a bit boring :)

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I think real pilots usually disconnect the AP just before 1000 feet, at 1000 feet you should be in any case stable on approach (speed, flaps, gear, spoilers armed).

If weather is fine I disconnect AP at around 1000 feet or even sooner (if winds are calm), in low visibility (using CAT III) I disconnect it before touch down.

There is no problem with the pitch itself I think, it is just that nose dive at AP disconnect which should be taken care of.

About the flaps, I have normally selected flaps 1 before intercepting the glidescope, flaps 2 when glidescope is alive and on track (also gear down at that point), then flaps 3 and flaps FULL (before 1000 feet). Usually if you see the pitch increase then it is time to increase position of flaps. If at the end this still not works then speed have to be reduced.

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I've been disconnecting the AP at 1000' rather than five hundred so as to have a better chance at recovering from the nose dip, but perhaps I should try as Paul suggests and intercept the glide slope manually.

I have found a table of A320 reference speeds as well as an article on how VAPP is derived from VREF and I will look at that to see if the FMC or whatever you call it in an airbus is giving me an appropriate speed. If it is, then I will go into the aircraft.cfg file and start tinkering with the flap lift.

Thanks for all the suggestions.

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From the tables I looked at, it looks like the FMC is giving the VREF speed as VAPP. VAPP should be VREF plus five knots plus a wind additive. So I am adding at least five knots and setting the approach speed manually and that seems to work better.

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