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A320 problems

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EHM-2097 Andrei:
Hi Didimo,

I can confirm about the barometric pressure gauge, I find too that it behaves strangely, but it looks to me more like an unexpected feature ;D than an actual bug.

I think there are two hotspots on that gauge:
- one that switches between milibars and inches;
- one that switches to standard 1013 milibars pressure ABOVE 18000ft. Below this level it does nothing.

If this is true (and not mixed up by my imagination :) ), the correct way to use this gauge is wait until 18000ft THEN use it to switch to standard pressure. I have done this while flying online and it works (still, if any doubt persists, can anyone confirm or infirm this behaviour?).

However this is bad for Propilot flights, it means you only have a split second when reaching 18000ft to switch pressure before getting penalized. Or fly in fair weather...

I can't tell much about the other problems you encountered. Never tried to get it stalled and for taxiing I cheated = fitted it with the ground panel which autocontrols ground speed.

Cheers
Andrei

EHM-1821 Javier:
I'm using the freeware Ken Mitchell panel with the Ifdg A320, i cant find the hotspot to manually change the pressure gauge either, so i just press "b" :]

I just tried stalling the aircraft at FL340, the aircraft sinks like a brick! i fell from FL340 to 200 in less than a minute, only recovered when the airspeed reached 330KIAS, and by the time i recover, i'll be overspeed :% so the verdict is, recover as fast as you can once you hear the stall horn or you'll suffer a horrifying dive:]

and about the A320 being overpowered, I dont think it is. I installed the ACS panel for the MD-11 a few days ago and it also includes a edit to make the plane feel real on the ground. When i tested out its braking, it felt pretty much like the A320, slowly coming to a stop, so i don't think it is a problem, maybe a realistic addition, not sure how the A320 brakes in real life though :s

EHM-2198 Didimo:
The barometric gauge is unfortunate because you expect your hotspots to be on the correct place, otherwise you spend time clicking like a madman taking away your concentration for more important things. Also, if you are below TA and instructed to change your barometric setting then you are at a loss. I find that quite disturbing.

The idle power thing is not a problem for me, just wanted to mention it.

The stalling is quite disturbing, mine plummeted from FL240 to under ground level in around 30 seconds. Never had problem recovering from a stall until this one. When it plunges down it does not even respond to you pulling up the yoke (elevator up). This incident however reminded me an episode of CRASH INVESTIGATION in which a Russian airline was flying their brand new Airbus from Russia to near Japan and the captain brought his son & daugther to let them play with the yoke. It was in autopilot, little did they know that even in autopilot if you pull/push/turn the yoke too "persistently" then the computer overrides the autopilot and assumes/d you want to take control. At night and such as speed they did not notice they were turning and then the a/c went down like a brick and they could not bring it up and.... CRASH...

NEW ISSUES DISCOVERED:

- When autopilot is set and have plan is known when you enable the GPS button on the panel the AP does not follow the route on the GPS. The GPS button appears to me only animated (on/off) but not really operational.

- Controlled descent appears not to work unless I did something wrong. I was at 25000 and wanted to do an automatic controlled descent to 13000. Set new (lower) altitude, enabled ALT and AutoThrottle (AutoPilot was ON), it appeared to descent but not at the calculated rate and the auto-throotle was not really working because it remained at 80%. I had to disable it and do it manually after the test (throttle to idle).

EHM-1001 Robert:
Well,

it is strange as we are talking about a stall. Maybe the Stall warning comes too late, but I do not know many planes that can recover from a Stall so easy as you want. I do not mean the moment when the horn starts shouting... I mean the moment when the plane already bowed and start falling down. In this case your only chance is to gain speed and "Pull up in time !..."

If there is not enough thrust but the autopilot tries to keep her up i nthe air, yes it will almost stop before falling down...but will fall down like a brick ! If you drive it with your hands, you can recover a stall easily, but the autopilot will not do it ! It will do its job and follows YOUR commands: it will keep try to climb even without thrust...why do you feel it is strange ???

Not the autopilot should recover nicely from a stall, but the pilot should be wise enough to not push his plane until stall ! Un fortunately there is not Fly-by-wire yet in FS, so its up to the pilot. ;)

BTW, how could you stall it at all unwantedly ? IF you see a large jet losses speed and it goes under 200kts you need to level it immediately to gain speed again. You need to take care about the payload too, and you should not want to push her up to the ceiling limit right after takeing off with MTOW ;)

And yes, some lighter jets (even B737) rolling at idle power ! But not the A320 ! You might have some bug around your throttle settings.

EHM-2198 Didimo:
I was test flying the thing. It is possible to make it happen, in fact I induced it yet again.

I placed it in autopilot (AP+ALT+VS) throttle around 75% I think. The nose was slightly up. After a while I noticed the nose was too much up (pitched up), around 30 degrees which is not natural for level flight.

Then I added the auto-throttle thinking that since it would AT it would not need to pitch up to go level. Hum... WRONG! after a little while the thing went into a STALL.

Yes, of course I know how to recover from a stall and I have NEVER EVER tried to recover from a stall with an Autopilot on.

Then it started to stall, in a matter of seconds it started falling down like a brick in a nearly uncontrollable spin. Down, down. As soon as that happened I disabled AP.

still going down like a brick, since it was upside down I had to abuse my yoke to try to bank it 180 degrees, was not so easy as it tended to go belly up again. In a matter of seconds (don't ask how many, I was busy recovering from the thing) it dropped 12000 feet. The clue in recovering from this mega stall (and a postmortem black box would have shown it) was to reset the pitch. I noticed that the AP had moved the elevator trim to pitch up +15.0 !

By this time the plane is at overspeed (some 400 knots) so another situation to recover from.

Finally at 8,000 I had the plane under control. So here, massive altitude drop, nose down dive, uncontrollable spin during dive, overspeed.

Believe you me, NOT something I would like to experiment in real life!!!! nevertheless I think:

a) There is possibly something wrong with the algorithm used by the autopilot which causes too much positive feedback thus enlarging the problem.

b) Even though it is simulation it IS stressful but wow, what a way to polish up simulation skills! If I could only had "saved the flight" during the spin I could have it for a training session!

I think I will try it some more with and without auto throttle. Anyway, I am loving this airbus, so far I had been a Boeing 737/767 sim driver :)

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