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A320 how to save this landing

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A320 how to save this landing

Old 5th May 2010, 15:51
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Beau_Peep
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A320 how to save this landing

friends, I was shooting a VOR approach today with 8 kts tailwind. things were fine upto 50ft, when suddenly wind died to zero. airplane started dropping, I pull the stick little up to increase the lift but controls were sluggish and didn't respond. just a second before touchdown airplane pitched up (may be the late response) and I cut the throttle. I had a 1.72g landing.
What could be ideal technique to save or rather reduce the 'damage' on this landing?
IFLY_INDIGO is offline  
Old 5th May 2010, 16:14
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A go around?
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Old 5th May 2010, 16:14
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Why would the aircraft drop if the tailwind dropped to zero?

After an excellent landing etc...
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Old 5th May 2010, 16:15
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Just pulling back without increasing the thrust is inviting a tail strike. This is basic high rate of sink landing recovery. If it is really bad then a go around would be in order.
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Old 5th May 2010, 16:19
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Don't close the thrust levers so early if you feel you have run out of energy. If you end up leaving them on too long and float deep, go around.

P
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Old 5th May 2010, 16:23
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b737NGyyc, the autothrust (that would normally be ON even for manual landing on a Bus) should have taken care of that. I assume the problem was that the thrust levers were closed just as the autothrust reacted.
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Old 5th May 2010, 16:31
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Why would the aircraft drop if the tailwind dropped to zero?
My simple non- Airbus twopence worth: Down to 50' (in this case) higher than normal Groundspeed due to the tailwind, so you have a higher than normal ROD to hold the glideslope, so the power's is back below normal headwind figures . Then at 50' you run into what is an effectively increasing headwind, Ground speed drops, ROD is still high, power's back ...if you or the AT don't increase the power you may start dropping short, if you pull the power off....

Standing by to be corrected.
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Old 5th May 2010, 16:40
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b737NGyyc, the autothrust (that would normally be ON even for manual landing on a Bus) should have taken care of that. I assume the problem was that the thrust levers were closed just as the autothrust reacted.
As you can see from my pseudonym I don't fly the Airbus and never have but my experience with autothrust (throttles) is that they are rarely responsive enough to react to a situation such as this.

Having no experience on the Airbus I can only presume that they can be manually overridden if required by pushing the thrust levers forward. If the autothrust on the Airbus is responsive enough to handle this situation then that is great but from my experience pulling back and expecting the automation to save the landing is too much of a leap of faith for this stick and rudder guy.

All the bells and whistles are great but in some situations, such as this one, manual intervention is the way to go IMHO. More and more I see it on the line that there is too much reliance on the automation and more and more erosion of basic piloting skills.
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Old 5th May 2010, 17:41
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IFLY

What did your Captain say?

He might be your best bet for some ideas on how to "save" the landing.

You have some very high time airbus drivers at Indigo, who I'm sure would be more than willing to share their experience with you.

I agree with some of the other comments made so far.. In that you can't rely on the automation to save the landing.

Keep a good eye on what the winds are doing... or have your PM to do that... watch for a trend and be ready to respond.

At what point did you take out the A/P? If you are low time, esp with the silly rules in India... where you as a F/O can't takeoff and and land unless on a special list (yes that right! a FO can NOT take off and land unless with a TRI/TRE)

You should consider taking out as much automation as you can... learning how to fly the aircraft by hand.. and building up the reflexes so it is second nature and you will see a trend developing much sooner.

Also, if things start to look bad... offer control back to the left... or GO AROUND.

If you ever fly something bigger... you really need to think about a tail strike as from what you say happened that was on the cards...

Just my 2 cents.

PT6A
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Old 5th May 2010, 18:03
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I do not know the center of lift in relation to the gear in the A-320, often a pitch up at this hight to reduce the rate of decent can result in a higher rate of impact for the gear if it is aft of the axis the aircraft is pitching on. But as a few have said before, you did not have a resolution for the problem presented to you a GO-AROUND should have been the first instinct.
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Old 5th May 2010, 18:16
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Hi IFLY_INDOGO,

My two pennies worth:

.. with 8 kts tailwind. things were fine upto 50ft, when suddenly wind died to zero. - If wind suddenly died to zero, air speed should have increased - Good.

airplane started dropping, - result of reducing ground speed and maintaining original ROD - Bad.

I pull the stick little up to increase the lift but controls were sluggish and didn't respond. - with increased airspeed, controls should have behaved normally - possibly an illusion due concentrating on touch down point -need to look further down the runway.

just a second before touchdown airplane pitched up (may be the late response) and I cut the throttle. - initiation of the flare was too late with high ROD.

I had a 1.72g landing. - Ouch.

What could be ideal technique to save or rather reduce the 'damage' on this landing? - With a tail wind and higher ROD - be prepared to flare a bit earlier and look further down runway to judge flare attitude change.

If you get into a similar situation again - do a "TOGA 10". Set TOGA power and rotate to 10 degs pitch up. This will prevent a tail strike on A320 / 319. After touch down, and when safely climbing away - do the normal "Go Around Flaps" rotating towards SRS / 15 degs.
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Old 5th May 2010, 18:28
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As difficult as it can be to accept it, it's never too late to go around, even if you've touched down (although deciding to 'go around' when you're down to 50kts may not be such a good idea!)

If you feel the lift start to drop off, do NOT close the thrust levers, even if it's yelling retard. Keeping the thrust on (be it in SPEED or Manual), even until you touch down, can turn a heavy landing into just an uncomfortable landing.

Phase Advance is a great tool on the approach but remember that it doesn't work below 100ft RA.

Listen to others, learn from it and move on. Don't dwell on it and let it get you down!
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Old 5th May 2010, 19:53
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I was shooting a VOR approach today with 8 kts tailwind. things were fine upto 50ft, when suddenly wind died to zero
Just out of curiosity, didn't you get any help from GS Mini here ?? AC energy should have remained as high as needed for sudden wind changes ...
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Old 5th May 2010, 20:10
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Hi fredgrav,

didn't you get any help from GS Mini here
"Ground speed mini" holds a suitable minimum ground speed based on the reported wind entered. With a tail wind on the approach you have a bigger ground speed - so GS Mini does nothing.
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Old 5th May 2010, 20:52
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Is a 1.72G landing within limits? I.e. was an engineering inspection required? Not a bus driver myself so just wondering.
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Old 5th May 2010, 20:52
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Hi rudder & studi,
sure, erroneously interpreted the decrease of TW as a lack of HW on final ...
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Old 5th May 2010, 21:04
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If my memory serves me correctly its 1.8G that needs MX.

However a pilot SHOULD report a hard landing... as per the advice from the UK CAA as I don't think those readings are always spot on.

Would be curious if the orginal poster reported his landing.....
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Old 5th May 2010, 23:17
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Hi IFLY INDIGO,

As has been said, the loss of tailwind would, everything else being equal, give an increase of IAS.

Did she bounce?

With VS higher than normal, flare needs to be started earlier (higher), and thrust retarded later (as has been said above), unless you are “fat” on IAS. If you realise you’ve left it too late, the only safe option is a go-around, because flaring will dig the main wheels in on the A320, just as on most aeroplanes with tricycle L/G.

A last-moment attempt to arrest the sink with a big burst of thrust is not something I would recommend − even if you are using manual thrust (my preference for most manual landings on the A320). It can lead to all kinds of problems, particularly on a short runway. If you do decide to continue, better to leave the power alone, but, if you have to ignore the “retard” call initially, don’t forget to do it once you are safely on the ground… Many of us have.

Yes, it’s easy for us to be wise while we ponder at our keyboards, or watch you from the briefing room window, but it doesn’t necessarily mean we would have done a better job than you did!

Chris
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Old 5th May 2010, 23:47
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why is there a last FCOM engineering bulletin recommending not to move the thrust levers above climb?
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Old 5th May 2010, 23:56
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I don't have that in my manual... Do you have the number and I can look it up...

PT6A
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