63 replies to this topic

[Arm Out The Heli]

How about I explain power and pitch controlling the state of flight for helicopters and annoy you all?  

[Drak]

I tried to reproduce what you were doing, and I think the setting were quite the same.
(By the way the FD came on when I disengaged the AP/ATHR I think)

01


02


I managed to land it quite nicely though. You aren't in some way applying full backwards thrust which is then interpreted by the airplane as something 'bad' are you?

[jnz]

I'd just like to point out that when you pitch up, you also need to increase power to keep airspeed. When you pitch down you need to reduce power to keep airspeed too. So you're both right...

In NWilkinson's case, if he wants to slow descent rate a touch for example, he will increase power (to slow down the descent) and pitch up (to keep the aircraft's speed constant)

In mine, and other people's. I will pitch up (to slow down the descent) and increase power (to keep the speed constant).


Although my only experience is on the FS series so my opinion is probably mute.

[Salty25]

I'm not sure what is going on.  I found the TOGA button and it is pressed when the ATHR button is lite.  If I select A/P I can deselect ATHR, but as soon as I turn off the A/P the ATHR comes back on again.

I guess I could just keep flying the Boeing line, just wanted to try a different platform.  But, if I give up on it and move on I will feel like I was defeated in some way.

I looked around the c/p and could not find any switches that matched what was suggested by JetPilot.

But, when I do select A/P I can adjust the throttles; but the plane wants to just climb straight up even if I put nothing or 2000 in the altitude window.

[Salty25]

Well, I got to land the A321... finally.  I landed it at two different places, KNUW and CYYJ.  Both times went just fine.  Lined it up and flew the G/S down to the runway, touched down at about 150-155.  Deployed the spoilers and came to a stop, taxied the opposite end of the runway, turned around and took off.

Then I flew over to KBLI and lined up.  The ATHR started acting up on me again.  I figured out if I hit the A/P, go to full throttle and turn off the ATHR I could then turn off the A/P and it would not come back on.  The only thing is it came on twice while I was on final.  But I figured out what to do so when I saw the N1 creeping up I quickly did those steps and got it back to idle.

End result; I landed the A321 at KBLI like I wanted.  Spent so much time paying attention to the throttles and gauges that I came in slightly to the right, right main off the runway.  But it'll get better with time and practice.

Thanks for the help everyone.

[Capt_Gabe]

Salty25, on the FSX Airbus there are 3 switches on the left hand side of the overhead panel called ELAC1 SEC1 and FAC1, I have no idea what the correct function or explanation of these switches is, (perhaps an Airbus jock can explain the detail for us), but, they have something to do with the Airbus modes of flight control, "cleverness" programmed into the flight control computer systems to stop pilots doing things that would break the airplane. I have had approach situations where I was all messed up on the approach and it looked like I was going to crash so the "cleverness" took over and a whole load of non-pilot (me) initiated stuff happend, throttles up, pitch up etc. So if you switch off those 3 functions you should retain total pilot control of the bus.

[THBatMan8]

ELAC - Elevator Aileron Computer / normal elevator and stabilizer control. Aileron control
FAC - Flight Augmentation Computer / Rudder control
SEC - Spoiler Elevator Computer / Standby elevator and stabilizer control / normal spoilers control

*EDIT*

The seven FCC's process pilot and autopilot inputs according to normal, alternate, or direct flight control laws. There are 2 ELAC's, 3 SECs, and 2 FACs.

Flight Control Data Concentrators (FCDC) aquire data from the ELACs and SECs and send it to the electronic instrument system (EIS) and the centralized fault display system (CFDS).


Guess that means I'm a Airbus jock.  

Edited by THBatMan8, 31 March 2009 - 04:34 AM.

[Capt_Gabe]

THBatMan8, on Mar 31 2009, 04:20 AM, said:

Guess that means I'm a Airbus jock.  

LOL.

I never did have the courage to go figure out what they all meant, cheers.

[THBatMan8]

Capt_Gabe, on Mar 31 2009, 05:43 AM, said:

THBatMan8, on Mar 31 2009, 04:20 AM, said:

Guess that means I'm a Airbus jock.  

LOL.

I never did have the courage to go figure out what they all meant, cheers.

Yeah the Airbus system is confusing compared to it's Boeing counterpart. IE on most Boeing's 1 FCC (Flight Control Computer) controls the surface commands to the autopilot servos. The Yaw Dampers control the rudder on all phases of flight except during a multiple A/P coupled ILS where the addition of 1 or 2 FCCs adds rudder and nose wheel steering. There are only 3 FCCs on most Boeing's while most Airbuses have 7   .

Airbus =  

Edited by THBatMan8, 31 March 2009 - 02:34 PM.

[THBatMan8]

To add to what Jet Pilot said earlier,

The thrust levers are the main interface between the Flight Management Guidance Computer (FMGC), the Full Authority Digital Engine Control System (FADEC), and the flight crew.

They:

-arm the autothrust at takeoff, when "FLX" (Flex or De-Rated Thrust) or TOGA is selected
-limit the maximum thrust by their posn when autothrust is active
-disconnect the autothrust system when the flight crew sets them to Idle
-command the thrust manually when autothrust is not active
-engage the common modes (TOGA) when TOGA or FLX (for takeoff) is set
-when positioned between IDLE and CL detent [MCT in engine out] set the autothrust to the active mode

The Autothrust can also be armed, activated, or disconnected via the A/THR pushbutton on the FCU (Flight Control Unit)

As Nwilkinson said, the default A320 poorly represents the system as the Airbus is FBW (Fly By Wire) controlled but the default planes take everything to the traditional systems of pulleys and cables.

Edited by THBatMan8, 31 March 2009 - 03:28 PM.

[Salty25]

THBatMan8, on Mar 31 2009, 12:29 PM, said:

Yeah the Airbus system is confusing compared to it's Boeing counterpart...

Airbus =  

I'm no pilot but I have to agree; the Boeing line is less confusing.

I found the three buttons on the left, and four others on the right side of the same panel.  From the description provided they deal with Rud, Elev and Aile.  I'm having a little pickle with the ATHR and how to keep it off.

I flew the A321 a few more times last night.  I can' tell why it is turning itself on; it doesn't always come on when I'm landing.

[THBatMan8]

Try just setting the speed window on the FCU to your approach speed of around 140KTS and let the autothrust system handle the thrust until near the DH (Decision Height) (usually around 200FT AGL {Above Ground Level}). Then at the DH, disconnect the autothrust and move the thrust levers to the IDLE detent as you cross the threshold.

[THBatMan8]

Arm Out The Heli, on Mar 30 2009, 10:51 AM, said:

How about I explain power and pitch controlling the state of flight for helicopters and annoy you all?  

You would probably open a whole new can of worms with that one.    

[Salty25]

THBatMan8, on Mar 31 2009, 01:38 PM, said:

Try just setting the speed window on the FCU to your approach speed of around 140KTS and let the autothrust system handle the thrust until near the DH (Decision Height) (usually around 200FT AGL {Above Ground Level}). Then at the DH, disconnect the autothrust and move the thrust levers to the IDLE detent as you cross the threshold.

I tried that.  I put a speed in the window and hit the ATHR and it doesn't do anything.  It will fly past the dialed in speed and I have to use the throttles to adjust as needed.  So I figured fly with it and see what happens.  Well, I start lining up on final and it starts going full throttle again.  If I hit A/P, hoping it will control the speed it pulls straight up and keeps going.  I dial in an altitude and it still does that, if I put in 100 or 10000.

Airbus =     

[THBatMan8]

As you engage the A/THR you have to click on the speed adjust knob (it's the white knob on the FCU) after the A/THR system is engaged.

[THBatMan8]

Drak, on Mar 30 2009, 02:04 PM, said:

I tried to reproduce what you were doing, and I think the setting were quite the same.
(By the way the FD came on when I disengaged the AP/ATHR I think)
I managed to land it quite nicely though. You aren't in some way applying full backwards thrust which is then interpreted by the airplane as something 'bad' are you?

The FD stays on with the FMGS. I was wrong about that earlier as I didn't think this would be modeled in the default A320.

[Salty25]

Well, I couldn't figure out which white button you were talking about to push.  But, I think I got the A321 and that darn A/THR figured out.

It seems that if your AOA and your speed are near the point of a possible stall the A/THR goes to full throttle.  If you point the nose down and cycle your throttle it will give you control back.  So, by watching the N1 and noticing the RPM going up I push the nose down some and cycle the throttle.  When the speed comes up about an extra 20 knots or so, not exact, it will give you control of the throttles back.

Flew into KSEA a few times to check it out.  Landed pretty good, just left of center on 34L; i.e. my right main was on the center line.      Good by my norm, but of course could be better.





As I learned from ThBatMan8, didn't cycle the gear until I turned on final and that was when I dropped my last bit of flaps.  It was a smooth touch down but a little fast.

[THBatMan8]

Practice makes perfect.  

[Drak]

I was looking at the Just Flight Airbus manual yesterday, and it seems you fly the airbus almost straight onto the runway (3 or four degrees nose up max) or else you get a tailstrike (at 9 degrees+). Maybe you are indeed nose-upping too much for the autopilot

The button THBatMan8 means is labelled 'speed hold' if you have tool tips on and hold your mouse over it. It is the speed adjuster knob, between 'SPD 140' and 'SPD MACH' in your screen shot.

Yes, you can actually press that and it will go aslightly darker (or lighter) shade of gray.

[Alaska_MD-83]

Salty25, on Mar 31 2009, 11:58 PM, said:

Well, I couldn't figure out which white button you were talking about to push.  But, I think I got the A321 and that darn A/THR figured out.

It seems that if your AOA and your speed are near the point of a possible stall the A/THR goes to full throttle.  If you point the nose down and cycle your throttle it will give you control back.  So, by watching the N1 and noticing the RPM going up I push the nose down some and cycle the throttle.  When the speed comes up about an extra 20 knots or so, not exact, it will give you control of the throttles back.

Flew into KSEA a few times to check it out.  Landed pretty good, just left of center on 34L; i.e. my right main was on the center line.      Good by my norm, but of course could be better.

As I learned from ThBatMan8, didn't cycle the gear until I turned on final and that was when I dropped my last bit of flaps.  It was a smooth touch down but a little fast.

I thin kthat was me.. Not Bat