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FLEX1978

A321 A.Floor Message

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Guest WSTS

How do you "Clear" the Afloor message when flying the A321? Turning off the autothrottle/takeoff go around button will not stay deactivated. I realize the jet "Thinks" it is trying to save us but with no control over the throttles, I continually crash the jet.Terry

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Guest WSTS

I am writing this second entry because the forum would not allow me to edit the first one. (too long since original was posted)After doing some web research, I read where someone suggested to just turn off the ELAC1, SEC1, and FAC1 switches on the overhead panel. As far as I can tell, this has "Deactivated" the "A.Floor" message and yet stil allows me to fly the jet with either a coupled approach (autopilot/throttle) or to disconnect the above and hand fly the touch down.I tried to find out what those buttons actually stood for but I could not find any info in the help section of FSX. You would think that if MS took the time to "Model" those switches into FSX, they would at least tell you what they did and or how they are suppose to work.Terry

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Guest WSTS

Tord, Thanks but remember that Microsoft sometimes falls "Short" of getting their aircraft to act like the "Real" jet. When the throttles are locked up in the A.floor/autothrottle mode, you can (I have not found out yet) move them back. To further explain that, if I turn off the autothrottle then yes they will move aft but the autopilot will not let you manually turn the aircraft. Disconnect the autopilot and then the autothrottle/takeoff go around activates again. I guess I will continue to fly with those 3 switches turned off as long as it does not seem to effect the rest of the flight.Terry

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Guest allcott

Alpha Floor is an autopilot MODE, not a warning message, it protects the aircraft against excessive angle of attack - or Alpha - which might cause a stall. You could read it as a caution that the aircraft is in landing mode. TO/GA is automatically applied when the AOA exceeds the threshold. Sounds like you are trying to flare on landing. "The 737 thanks you for flaring, the Airbus spanks you for it..."The Airbus is not flared, it is flown straight on, with controller forces mimicking a flare ro provide a degree of commonality with conventional aircraft. This is felt in the sim as a sudden trim up.The FSX manual is totally inadequate in its explanation of Airbus systems, what systens are implmented in FSX and how they differ from say, the 737.Allcott

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Agree except Alpha Floor is part of flight envelope protection and available whether the autopilot is on or off.


Regards

 

Howard

 

H D Isaacs

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Guest WSTS

Thanks everone who has tried to explain this Alpha Floor thing. As long as I can hand fly the jet when I want to and still use the autopilot for the rest of the flight, I will just leave those three above swiches in the OFF mode. Then I will not have to fight with the aircraft for who is suppose to be in control.Many years ago, General Dynamics put a SIS (stall inhibitor system) on the F-111 series aircraft. In theory, it worked good when you were flying straight and level but if you needed to increase your alpha (something fighter aircraft do a lot of in flight), you would have to fight the aircraft to keep your nose up. In particular, there was a certain way you could deliver your bombs on target that required your nose (alpha) to be more than just straight and level. This is not a good time to be fighting your aircraft while someone is probably shooting at you. I seem to remember that the crews would just pull the C/B (circuit breaker) to take the SIS off line so they could do their jobs.Terry

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Guest iwantmydc3

Ah, so it's SUPPOSED to do this? lol. I have been trying for weeks to figure out what I might have been doing wrong. I like flying the airbus except for trying to land it. That daggone GOTA mode. So, what it's a three poing landing then, oy.>Alpha Floor is an autopilot MODE, not a warning message, it>protects the aircraft against excessive angle of attack - or>Alpha - which might cause a stall. >>You could read it as a caution that the aircraft is in landing>mode. TO/GA is automatically applied when the AOA exceeds the>threshold. Sounds like you are trying to flare on landing. >>"The 737 thanks you for flaring, the Airbus spanks you for>it...">>The Airbus is not flared, it is flown straight on, with>controller forces mimicking a flare ro provide a degree of>commonality with conventional aircraft. This is felt in the>sim as a sudden trim up.>>The FSX manual is totally inadequate in its explanation of>Airbus systems, what systens are implmented in FSX and how>they differ from say, the 737.>>>Allcott

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Transition to flare mode occurs at 50' RA during landing. The System memorizes pitch attitude at 50' and begins to progressively reduce pitch, forcing the pilot to flare the aircraft. In the event of a go-around, transition to flight mode occurs again at 50' RA.The real aircraft won't enter Alpha floor below 100' radio altitude to avoid Go-around thrust if you accidentally hit alpha floor AOA during a normal landing flare (this is why we have the famous video of an a320 flying at low speed into a forest) Rob


Rob Prest

 

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Guest QR045
How do you "Clear" the Afloor message when flying the A321? Turning off the autothrottle/takeoff go around button will not stay deactivated. I realize the jet "Thinks" it is trying to save us but with no control over the throttles, I continually crash the jet. Terry
i have done some experimenting and found an easy way to get out of alpha floor.1st situation: i got into alpha flor and didnt touch the controls at all. the plane nosed down ond overspeeded.2nd situation:same as above exept when i got into alpha floor, i pushed down on the stick and alpha floor disengaged straight away (or at least above a safe speed).

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As long as I can hand fly the jet when I want to and still use the autopilot for the rest of the flight, ...Terry
Troll Alert --> Why are you flying an Airbus if you want to fly it yourself? :( :(

Tom Perry

 

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this is why we have the famous video of an a320 flying at low speed into a forest Rob
I think the main reason we have that video footage is because the crew were hugely foolish in taking an aircraft that was carrying 130 passengers right to the edge of its flight envelope; and this without being familiar with the airfield they were doing it at, or doing a proper briefing for a highly unusual procedure on a passenger flight, or for that matter, even a recce of the airfield where they were performing the demo. The captain was the fleet training manager for the (then) new A320 at Air France, but it was still a new aircraft to him and the co-pilot (only the ninth one ever built if I recall correctly), and they pushed it way too far.The FDRs show that they were actually descending at 800 FPM when only 100 feet above the runway with the throttles still at flight idle. And when they applied full power for a go around upon seeing the trees ahead of them and the HT pylons which are to the left of them (which they hadn't bothered to check on the existence of, prior to starting their demo, or even check which runway the people at the airshow were lined up along), they were at such a high angle of attack, that regardless of whether the thing had fly by wire systems or not, it was an accident waiting to happen. For beyond all that fancy fly by wire stuff, it is still a conventional aircraft, and in those circumstances, it was going to crash whatever they could or could not do with the stick. It took five seconds for the engines to spool up to just over eighty percent thrust (which is normal, and the crew should have been aware of that), which meant they were still only at 93 percent thrust when the aircraft started hitting the trees, creating even more drag than they already had on the thing when wallowing along nose high at 122 knots in dirty configuration with the engines throttled back over a tiny grass airstrip.Ultimately, their stupidity killed 3 people (two of whom were children, one of these handicapped and therefore unable to unfasten his own seatbelt, the third person being a woman who went back into the aircraft wreckage to try and rescue a child and was overcome by smoke). 34 others were severely burned in the crash too, with many others also being injured. I suspect there's probably never been a better demonstration of irresponsible and overconfident stupidity from a crew in the history of aviation.Incidentally, the crew deactivated the Alpha Floor function on that aircraft on the run in to the airfield prior to their crash, which, had they not done so, would automatically have spooled up the engines as the angle of attack went up.Al

Alan Bradbury

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