Hard landing/bounce on 320 fleet

[Boroda]

320 is known for its directly noninterconnected sidesticks, casing some difficulty in correcting.

If you don not mind share please your expierence on this topic: interesting own cases, company politics on correcting abnormal landings, flying with newcomers.

Also it would be nice to find out more about load report VRTA. What is VRTA relation with actual load, that is figure indicating how many times weight on touch more than landing one, that is without load in air due to rotation.

Thanks.

[Carnage Matey!]

If you need to correct the other pilots landing then state clearly and LOUDLY "I have control", press and hold your sidestick priority button and take whatever corrective action is necessary. That really is the only acceptable sequence if you need to make a sidestick input, anything else with lead to a messy arrival.

[Founder]

Here you can find information about how to handle "bounce" landings and additional landing technique.

Airbus - Corporate Information - Ethics & Commitments - Safety first library (http://www.airbus.com/en/corporate/ethics/safety_lib/)

[NWSRG]

How long does it take the 'priority' button to work...it seems to be a press and hold function? If seconds are vital...

[Boroda]

Yes, I agree there is no another way exept for priority p/b. But it is rather long method sometimes. Moreover another pilot in mess presses it also often. That is why I arise this problem, and often the only way is to make a GA.

And what about VRTA in load report?

[Boroda]

FOUNDER, thanks for reference, but it is pity - no new info.

[scudbus258]

By double pressing the ap/priority button you gain priority over the other side stick. An aural 'priority left/right' is heard, red arrow to the side of the fcu pointing to which side has control over the other/green on side which has prioriy. If the button is held down for 20-30 secs you lock out the other side stick for the remainder of the flight and can only be reset on the ground. (p45 button). Only used in extream cases but was mentioned during my type rating as only using this in-case of side stick malfunction. Hope this helps........

[Boroda]

Thanks, on our fleet the last pressed this button has control, but to latch priority he has to hold it more than 40 sec. And to cancel this condition just touch any "magic" button again any time.

But VRTA - what is it actually? What is the max allowable and respective measures for aircraft/crew?

[casper63]

VRTA - Vertical Acceleration at the time of touch down is recorded in load report #15. In my assessement the landing could be classified in the following manner:-

1.1 g very smooth
1.1-1.2 smooth
1.2-1.3 average
1.3-1.4 firm
1.4-1.5 very firm
>1.5 hard
>2.0 very hard requiring hard landing checks.

Any comments/corrections anyone?

[Boroda]

I have such figure of VRTA as 2.6, after which check is required. And having hard landing expierence on other types I tell you that according to own feelings real 1,5 on others is more than 2 on 320. And sometimes it is opposite feelings. I would like to say that load report VRTA sometimes does not correspond to own feelings. You may land smoothly but VRTA is 1,5 and vice verse. It seems to depend on pitch change rate before touchdown.

[BigFootDriver]

This is an inappropriate public venue to share flight control operation in this detail.

Terrorists frequent forums like PPRUNE to further educate themselves on aircraft opeartion.

Please don't feed their sick agendas.

My carrier lost two aircraft on 9/11. We are very sensitive about this.

If this guy needs detailed info, let him secure it thru official channels.

[tom775257]

scudbus258: Your SSC take-over theory is incorrect. It is the autothrust that can be locked out by holding the 'instinctive disconnect switches' until after the flight, nothing to do with the side stick.

The SSC indeed can be reactivated by pressing the button on the other stick in flight. The latching is there in case the other chap/chapette is slumped on the stick / side stick failure. Pressing and holding gives priority straight away.

BigFootDriver - I can assure you a good working knowledge of the airbus stick logic is unlikely to enhance any hijack scenario... Personally I would worry more about the people who are being recruited up through airlines who are currently worrying captains with regards to their various views on life and beliefs, but, ahem. help the pro diversity figures companies seem to strive for. A different story entirely.

[Bula]

Anyway for us the check this in a post flight report format. Maintenance post flight report, CFDS etc etc etc

[el #]

BFD:

1. All and any detailed information about airplane operation is already on the Internet free of charge for anyone. It's of no use that you come here trying to censorship a professional discussion. Beside, when matters of true concern regarding security are inappropriately discussed, the moderators will intervene.

2. Next time when referring to 9/11, perhaps mention the loss of human lives or the distress for survivors instead of the two planes that "your company" has lost. That will put yourself in a better light.

[vikena]

Well said el

v

[NVpilot]

Big foot, no disrespect but no airplanes got hijacked do to information supplied on a pilot forum.

[Boroda]

Let me continie according to theme.

Suppose a scenario:
low flare and the first touch is the result of uncompleted flare, thrust well above idle. Bounce up to 5 feet. What are you going to do? RW length is enough.

[NVpilot]

TOGA :ok:

NV

[BigShip]

just a little info from my technical captain, that information taken from the onboard system available for pilots is not accurate regarding vertical g-loads at touchdown, since the measurements are taken at different position or time.

sorry can not remember all the details exactly.

just wanted to share this info.

[bflyer]

Let me continie according to theme.

Suppose a scenario:
low flare and the first touch is the result of uncompleted flare, thrust well above idle. Bounce up to 5 feet. What are you going to do? RW length is enough

If by enough you mean, let's say 1500-2000 ft and favourable conditions exist..i MIGHT attempt to recover..another smoother touchdown then it is time to salvage one presumably wounded ego

99.9999% of the cases it's best to go around for another better planned approach and landing....
btw..do you get the load report as part of the pfr ?

[Boroda]

Why not to land? Is 5 feet high for you or do you have another reason?

By the way is it possible that ground spoilers ( to continie popular Colsie thread about spoilers) might extend at 5 feet after bounce if I decide to land & set levers to idle.
According to FCOM they extend (if armed) if main struts compressed & below 6 feet and Lever angle (not actual thrust) below 15 degrees. So technically it is possible to make hard landing from even 2,3,4,5 feet due to GS extension after bounce up to 6 feet & setting levers to idle.

[NVpilot]

Why, because bent metal costs big bucks, chances are if you didn't get it right the first time you don't have the skill to fix it either.

That bounce will take a lot of energy, now that you're out airspeed and ideas, what will be your next move?

a. Increase flare and hold on.
b. Lower the attitude and hold on.
c. Give it a shot of thrust (good luck).

[Boroda]

To Bflyer:

Affirm, we have load report, but not as the part of PFR. This situation is the real one. According to load report it was bounce up to 4 feet with thrust at 50% and down rate 350 after 1,65 first touch, thrust set to idle and the second touch with vert. rate only 200 ft per minute, but load is 2,2. Pitch is constant, no dual input. I wonder how it could be.

[bflyer]

I agree with NV pilot....the best option is to go around and figure out what went wrong the first time...then the new approach will count as a first one..otherwise, it will be a fight between man and machine..and the outcome is usually messy to say the least

[Boroda]

NVpilot:

You are absolutely right about reasons and consequences and еру best way out. But could you analize above described real situation?

[Doors to Automatic]

Should this have been a go-around:

YouTube - Bad-Landing at London City Airport 下手��陸 (http://www.youtube.com/watch?v=2hqJrpF25C0)

[bflyer]

Hi Boroda

here is my read on the event as best as i could

The first bounce might have been caused by a late flare with or without a downdraft caused by weather

The thrust levers were either retarded to idle completely or out of the CL detent on the way to idle at some intermediate position...but the thrust did not dissipate completely by touchdown and 50% of it was still produced by the engines..which, coupled with the reaction to the downward force produced the bounce

350 fpm at touchdown the first time corresponds to a HARD landing

It appears that the PF accepted the bounce..kept his thrust levers at idle and kept his pitch constant for the second normal touchdown at 200 fpm
(no pitch change)

As for the load being constant at 2.2 g...well i don't know...but my guess is that it is the sum total of the load exerted on the aircraft at this phase

best regards...
Bf

[Airbus Unplugged]

There was a big head called Tom,
Who didn't read his FCOM,

A pilot can deactivate the other stick and take full control by pressing and keeping pressed his priority takeover pushbutton. For latching the priority condition, it is recommended to press the takeover push button for more than 40 seconds.

He spoke through his $$$$,
Ended up in the grass,
And posted it on PPRuNe.com

[tom775257]

I know perfectly well that holding the button for 40 secs will latch after plenty of pilot incap in the sim, I am saying that the latching condition can be reset in-flight, unlike the comment earlier regarding needing a reset on the ground - which I suspected was a confusion with the autothrust lock out which does indeed need a reset on the ground.

Regarding use of the button in flight, I have yet to see anyone use it correctly on the line in terms of pressing the button and saying 'I have control.' When I first started on the aircraft and the training captain needed to correct my flare, generally he tweaked it with a 'dual input.' Then last year I did a month as safety pilot and again watching the new guys landing, the trainers if a correction was needed used dual input.

Another note, the 40 sec lock out seems to take forever in the sim, I have let go before now thinking at least a few minutes must have passed only for the other stick to not be latched out yet. I have seen other guys do this as well.

[Boroda]

BF:
Thanks for your read. The fact is that levers were without a doubt constantly at 50% from before the first impact until top of the bounce and it lead to GS nonextension (it became the main reason of the hop).
And I am looking for your confirmation of my theory about GS extension logic posted at post 21 - that once levers were set to idle (actually at 4 feet) GS extended (either struts had been still compressed after the first land attempt or smthg with proximity sensors after such a touch) and it caused despite the low rate (200fpm) such a load.
Do you think this idea about GS has a right to exist?
BRGDS, Boroda

[St. Ex]

Just to settle the issue, here's a quote from the A320 FCTM 01.020 Page 16 of 18:

"If a flight crewmember fails on a sidestick, or a mechanical failure leads to a jammed stick (there is no associate ECAM action), the "failed" sidestick order is added to the "non failed" sidestick order.

In this case, the other non affected flight crewmember must press the sidestick priority pushbutton for at least 40 seconds, in order to deactivate the "failed" sidestick.

A pilot can at anytime reactivate a deactivated stick by momentarily pressing the takeover push button on either stick."

Further, on page 17 of 18:

"Note: When a sidestick is deactivated by opposite sidestick priority pushbutton, it can be reactivated with its own sidestick priority pushbutton."

[frontlefthamster]

If the two sidesticks had been mechanically connected, then a number of accidents would have been avoided. The fact that despite maturity in the A320 world, landing accidents involving dual sidestick, and training accidents caused by the trainer's inability to assess sidestick inputs by his trainee, are far too common. (This aircraft is a nightmare to train on!).

Of course, Airbus say there is nothing wrong with the design...

But how sustainable this view is in light of the ongoing stream of accidents, and what we do to reduce the rate of landing accidents in this aircraft is a complete mystery...

(For my part, I've been thinking about buying some shares in Messier-Dowty!)

[Boroda]

Yes, as PNF I am always as if on a powder keg, moreover with newcomers.

[St. Ex]

from FCOM 1.27.10 p12a SEQ001 REV39:

"Note: After an aircraft bounce, the ground spoilers remain extended with the thrust levers at idle."

[Boroda]

StEx

The fact is that GS did not extend at the first touch because levers were at TLA of about 50 degrees and only after bounce were they set to idle.
Here we come to the logic described in FCOM just after your note where we can find that GS can be extented even up to 6 RA feet and thrust above idle. And this logic lead me to conclusion that when levers were idled and under condition struts had not decompressed by that moment GS extended as RA was at 4 feet. And that lead to hard landing from such a height.

[guiones]

Frontlefthamster:

Please quote the accidents you are refering to.

G

[NVpilot]

At my own airline we had a tail strike attributed to Dual Input on the A321, I myself am guilty on several occasions of adding input without pushing red button, sometimes only a small input is needed and I don't want to take the landing away from the other pilot, other instances require taking over.

[guiones]

From AIRBUS FLIGHT OPERATIONS BRIEFING NOTES

Landing Techniques
Bounce Recovery - Rejected Landing



Recovery from a light bounce
In case of a light bounce, the following typical recovery technique can be applied:

•
Maintain a normal landing pitch attitude:
−

Do not increase pitch attitude as this could cause a tailstrike; and,
−

Do not allow the pitch attitude to increase, particularly following a firm
touchdown with a high pitch rate.
Note:
Spoiler extension may induce pitch up effect.
•

Continue the landing;
•

Keep thrust at idle; and,
•

Be aware of the increased landing distance.
Recovery from a high bounce
In case of a more severe bounce, do not attempt to land, as the remaining runway
length might not be sufficient to stop the aircraft.
The following generic go-around technique can be applied:
•

Maintain a normal landing pitch attitude;
•

Initiate a go-around by triggering go-around levers and/or advancing throttle/thrust
levers to the go-around thrust position (depending on aircraft type);
•

Ignore the takeoff configuration warning, if any;
•

Maintain the landing gear and flaps configuration;
•

Be ready for a possible second touchdown;
−

Do not try to avoid a second touchdown during the go-around. Should this
happen, the second touchdown would be soft enough to prevent damage to the
aircraft, if pitch attitude is maintained;
•

When safely established in the go-around and no risk of further touchdown exists
(i.e., with a steady positive climb), follow normal go-around procedures; and,
• Reengage automation, as desired, to reduce workload.


SIDENOTE:

After reverse thrust is selected, a full-stop landing must be completed

[Boroda]

The same recommendations do we have at volume 3 FCOM bullitens. But there is no reference about what is low/high. My company SOP gives the bounce limit as 5 feet. And in case of low bounce we are recommended to adjust thrust to smooth the second touch opposite to airbus recommendations to keep idle. Any dual input during the flight is regarded as severe violation.

[Doors to Automatic]

Saw this on Youtube recently; looks like a last second wind gust caused a high-bounce.

YouTube - British Airways Go-Around Sofia Airport (http://www.youtube.com/watch?v=rQfESkzHPtM)

[Boroda]

Yes, from the cabin it lookes quite safe.

[rottenray]

Terrorists frequent forums like PPRUNE to further educate themselves on aircraft opeartion.

Please don't feed their sick agendas.

My carrier lost two aircraft on 9/11. We are very sensitive about this.:=

Whoa, bub!

I'm not trying to minimize the loss you and your company felt, but the facts are that the 9/11 terrorists learned what they needed directly from representatives of the airlines, from a flight school who was willing to teach someone paying cash and speaking broken english with no employment references how to fly a crop duster, and by practicing flying 767/757 aircraft on a personal computer running popular flight sim software.

And, not to kick a scab off a wound, but your airline (whichever it is, any airline, pick one out of your hat) has lost more hulls and pax to pilot error, poor maintenance, and bad weather than it has - or ever will - to terrorist hijackings. Except maybe Qantas, but that's a whole 'nother discussion...

And, TSA has killed and injured more people in or near US airports than terrorists have in the last 7 years.

Having an open discussion in this forum isn't "feeding a sick agenda," because as el # stated correctly back in post #14 (http://www.pprune.org/forums/tech-log/337602-hard-landing-bounce-320-fleet.html#post4308609) - more and better and easier to find info is already out here on the web.

Feeding a sick agenda? Suggesting that we all stop conversing in public for fear the wrong person(s) might be able to use something we discuss against us is feeding a sick agenda - it's preaching fear and endorsing censorship.



It's good that we're all aware of what lengths terrorists will go to, although it's sad that to be accurate, you have to say that we're FINALLY aware - terrorists have been using commercial craft to make their point for a long, long time now.

Don't you honestly think it's time to drop the "live in fear" attitude the Republicans have so greatly used to their benefit, and get back to doing our jobs and living our lives and enjoying our discussions?

...

[BigFootDriver]

Great idea....duh

Why don't you start a thread on defeating the electric cockpit door locking system.

I'm sure it will be interesting reading to the pprune members living in mud huts in Afganistan, and maybe you'll win yourself a parade for recklessly defending free speech.

Better yet, how about yelling "FIRE" in a packed theater (enjoy the jail time).

This legal matter was settled MANY years ago. Free speech comes with great responsibilities, and you need to grow up.

You are DEAD wrong.

And BTW the way, your COWARD moderators banned me for this post. Makes ya wonder about them eh?