Advice for Airbus newbie, tendancy to get slightly high/low
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From: Manchester
Advice for Airbus newbie, tendancy to get slightly high/low
Any advice greatly appreciated. Just started on the Airbus and struggling slightly with the last 500ft or so after AP disconnected to touchdown. I have a tendancy to drift slightly high or low, i tend to pay quite a bit of attention to my datum VS and the glide indicator and maybe not enough visually to the aiming point.
Any tips for keeping nailed on that glide, i have quickly learned that when this work a nice touchdown usually results!
Any tips for keeping nailed on that glide, i have quickly learned that when this work a nice touchdown usually results!
Joined: Apr 2010
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From: IRS NAV ONLY
Don't focus so much on V/S, but rather on the pitch. If you are on the glidepath, set pitch around 2.5 degrees (conf FULL) and then work around that figure to keep the aircraft on the glidepath.
Of course, if you are already visual at that point, it helps to keep the aiming point in the scan, but nevertheless you should look inside at that point as well. Try to also keep airspeed in the scan, which I know with A/THR is very tempting not to.
Of course, if you are already visual at that point, it helps to keep the aiming point in the scan, but nevertheless you should look inside at that point as well. Try to also keep airspeed in the scan, which I know with A/THR is very tempting not to.
Joined: Jun 2000
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From: last time I looked I was still here.
You could also try disconnecting the autopilot earlier so you get more time to get a feel for it.
Shock horror; but a good idea. The other question I used to ask pilots: you are in automatic mode; you are in trim & on speed; you disconnect, "What do you do?" Answer is , first nothing. PIO in lower levels is very common. In manual thrust a/c one of the first actions, unstoppable, was to nudge the power up. This started all sorts of porpoising. Then your hand gets twitchy in roll.
Much of this can be avoided by Aerocat's advice. With side sticks it is not so easy to keep it smooth & calm, so more practice, vicar, is the call.
Shock horror; but a good idea. The other question I used to ask pilots: you are in automatic mode; you are in trim & on speed; you disconnect, "What do you do?" Answer is , first nothing. PIO in lower levels is very common. In manual thrust a/c one of the first actions, unstoppable, was to nudge the power up. This started all sorts of porpoising. Then your hand gets twitchy in roll.
Much of this can be avoided by Aerocat's advice. With side sticks it is not so easy to keep it smooth & calm, so more practice, vicar, is the call.
Last edited by RAT 5; 16th January 2017 at 11:39.
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Thread Starter
Joined: Jan 2017
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From: Manchester
Thread Starter
Joined: Jan 2017
Posts: 5
Likes: 0
From: Manchester
Thanks all for the great advice. Yeah i think the mentality to leave the AP in for as long as possible isnt helping. Il start taking it out at 1000' or so, try and keep the 2.5 deg pitch in my scan. Use papis more until 200ft and stop relying on the VS so much.
And yes, dont touch the stick as much!
And yes, dont touch the stick as much!
Joined: Jul 2003
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From: Uk
The last 500 ft your attention should shift from inside to predominantly outside the a/c. If glide and attitude look right on pfd then look outside and take a snapshot. Then keep that same picture all the way down until you approach the threshold. You can even put a black dot (whiteboard marker) on the window where your tdz markers are and then just keep that dot on the markers all the way down. At 50 ft start looking further ahead to prepare for the flare. Have a good look when captains fly the approach so you get a better feeling for the picture outside.
Joined: Mar 2006
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From: USA
Thanks all for the great advice. Yeah i think the mentality to leave the AP in for as long as possible isnt helping. Il start taking it out at 1000' or so, try and keep the 2.5 deg pitch in my scan. Use papis more until 200ft and stop relying on the VS so much.
And yes, dont touch the stick as much!
And yes, dont touch the stick as much!
Joined: Dec 2008
Posts: 919
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From: uk
In the case described by the OP, I think that taking the ap out as soon as the a/c is stable, configured and trimmed is a good idea. Don't try for a super slick stable at exactly 1000agl. You could brief the CM1 that you want to be stable at 4 miles so you practice the visual segment. After the ap is out, very little control input is required on a reasonably calm day. Then concentrate on the papi's to train yourself to look outside and not worry too much about the instruments (PM should be monitoring the instruments), transfer your concentration onto the fixed distance markers at 200'. Which should take you down to the flare/ retard at about 20'.
This is a really common issue and is almost always down to overcontrol of the side stick.
If you are inadvertently overcontrolling when looking outside, consider making your grip on the sidestick very loose.
This is a really common issue and is almost always down to overcontrol of the side stick.
If you are inadvertently overcontrolling when looking outside, consider making your grip on the sidestick very loose.
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From: Where the Quaboag River flows, USA
How 'bout disconnecting at 10,000 feet, get some flying time, not watching the autopilot time. Remember the spot on the runway which us neither rising or falling on the windscreen is where the plane is going. Adjust as needed to put that spot on the touchdown zone. A HUD could help.
GF
GF
Joined: Mar 2006
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From: USA
How 'bout disconnecting at 10,000 feet, get some flying time, not watching the autopilot time. Remember the spot on the runway which us neither rising or falling on the windscreen is where the plane is going. Adjust as needed to put that spot on the touchdown zone. A HUD could help.
GF
GF
I know what you mean, sometimes it does seem to float above the GS. Just push it down. There's nothing else you can really do but apply nose down input. Correct a small deviation before it gets too big.
I also feel as though I have better control of the airplane (especially in the flare) with the AT off- particularly in the last 100ft or so.
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From: UK
My use of Airbus sidestick on an ILS approach (based on 11 years experience, for what it's worth):
DO hold it properly in a pistol grip, (you will need full control force on gusty days, so a proper grip is a good habit to adopt).
BUT normally if a correction on an ILS is needed, just nudge the stick for less than a second then allow the spring to return it to neutral. Nudge, return to neutral, nudge, return to neutral..........etc.
Each nudge will move the FBW attitude datum slightly, and the aircraft will then stay at that new datum. So if your VS is 500'/min, a nudge or two down (releasing to neutral between each) will make it 600'/min and it will hold that for you. Another nudge/s down will give you 700'/min.
A common mistake is to hold the stick out of neutral for too long, and then the aircraft moves a long way and you get into a PIO.
I think of it like this: a FBW Airbus effectively always has the autopilot in. When you "disconnect" the AP, you are just disconnecting where the AP gets its attitude commands from, the FMGC or you. It will hold the last datum it was given (and trim for you) until you make another input.
On an ILS, disconnect the AP at least 5 miles out to get used to the wind conditions that day, and so that by the time you are at 1000' feet, you have "calibrated" your inputs to the aircraft, and are completely in the groove and stable.
(On gusty days, the nudge release technique will not be enough, and on extreme days you may need to hold the stick full over at some points, but this will come with experience).
Good luck.
DO hold it properly in a pistol grip, (you will need full control force on gusty days, so a proper grip is a good habit to adopt).
BUT normally if a correction on an ILS is needed, just nudge the stick for less than a second then allow the spring to return it to neutral. Nudge, return to neutral, nudge, return to neutral..........etc.
Each nudge will move the FBW attitude datum slightly, and the aircraft will then stay at that new datum. So if your VS is 500'/min, a nudge or two down (releasing to neutral between each) will make it 600'/min and it will hold that for you. Another nudge/s down will give you 700'/min.
A common mistake is to hold the stick out of neutral for too long, and then the aircraft moves a long way and you get into a PIO.
I think of it like this: a FBW Airbus effectively always has the autopilot in. When you "disconnect" the AP, you are just disconnecting where the AP gets its attitude commands from, the FMGC or you. It will hold the last datum it was given (and trim for you) until you make another input.
On an ILS, disconnect the AP at least 5 miles out to get used to the wind conditions that day, and so that by the time you are at 1000' feet, you have "calibrated" your inputs to the aircraft, and are completely in the groove and stable.
(On gusty days, the nudge release technique will not be enough, and on extreme days you may need to hold the stick full over at some points, but this will come with experience).
Good luck.
Last edited by Uplinker; 17th January 2017 at 12:03.
Thread Starter
Joined: Jan 2017
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From: Manchester
My use of Airbus sidestick on an ILS approach (based on 11 years experience, for what it's worth):
DO hold it properly in a pistol grip, (you will need full control force on gusty days, so a proper grip is a good habit to adopt).
BUT normally if a correction on an ILS is needed, just nudge the stick for less than a second then allow the spring to return it to neutral. Nudge, return to neutral, nudge, return to neutral..........etc.
Each nudge will move the FBW attitude datum slightly, and the aircraft will then stay at that new datum. So if your VS is 500'/min, a nudge or two down (releasing to neutral between each) will make it 600'/min and it will hold that for you. Another nudge/s down will give you 700'/min.
A common mistake is to hold the stick out of neutral for too long, and then the aircraft moves a long way and you get into a PIO.
I think of it like this: a FBW Airbus effectively always has the autopilot in. When you "disconnect" the AP, you are just disconnecting where the AP gets its attitude commands from, the FMGC or you. It will hold the last datum it was given (and trim for you) until you make another input.
On an ILS, disconnect the AP at least 5 miles out to get used to the wind conditions that day, and so that by the time you are at 1000' feet, you have "calibrated" your inputs to the aircraft, and are completely in the groove and stable.
(On gusty days, the nudge release technique will not be enough, and on extreme days you may need to hold the stick full over at some points, but this will come with experience).
Good luck.
DO hold it properly in a pistol grip, (you will need full control force on gusty days, so a proper grip is a good habit to adopt).
BUT normally if a correction on an ILS is needed, just nudge the stick for less than a second then allow the spring to return it to neutral. Nudge, return to neutral, nudge, return to neutral..........etc.
Each nudge will move the FBW attitude datum slightly, and the aircraft will then stay at that new datum. So if your VS is 500'/min, a nudge or two down (releasing to neutral between each) will make it 600'/min and it will hold that for you. Another nudge/s down will give you 700'/min.
A common mistake is to hold the stick out of neutral for too long, and then the aircraft moves a long way and you get into a PIO.
I think of it like this: a FBW Airbus effectively always has the autopilot in. When you "disconnect" the AP, you are just disconnecting where the AP gets its attitude commands from, the FMGC or you. It will hold the last datum it was given (and trim for you) until you make another input.
On an ILS, disconnect the AP at least 5 miles out to get used to the wind conditions that day, and so that by the time you are at 1000' feet, you have "calibrated" your inputs to the aircraft, and are completely in the groove and stable.
(On gusty days, the nudge release technique will not be enough, and on extreme days you may need to hold the stick full over at some points, but this will come with experience).
Good luck.
Thanks Uplinker, great advice. Yes I think i maybe need to remember that it will hold the pitch with no input and to apply small movements and return to neutral when changes are needed. Most importantly i need to look out of the window more and trust my eyes to detect trends away from the GS rather than focus to much of my scan on the V/S.
Joined: Nov 1999
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From: UK
Yes, even when flying an approach manually, there are two of you flying the plane: the FBW* and YOU.
Airbus FBW will make small corrections to stay in the attitude you put it, even in light gusts, so let it do the work !
On an ILS - or even a visual - on a non turbulent day, you just have to occasionally nudge in roll or pitch to refine the flightpath, for example as the wind vector changes.
On more gusty days, the principle is the same, but the 'nudges' might need to be held for longer, but always return to neutral between each nudge.
* except for Direct Law
Airbus FBW will make small corrections to stay in the attitude you put it, even in light gusts, so let it do the work !
On an ILS - or even a visual - on a non turbulent day, you just have to occasionally nudge in roll or pitch to refine the flightpath, for example as the wind vector changes.
On more gusty days, the principle is the same, but the 'nudges' might need to be held for longer, but always return to neutral between each nudge.
* except for Direct Law
Last edited by Uplinker; 18th January 2017 at 10:45.