Dual Input Airbus
 

I've come across a number of pilots who claim that during a late flare from the F/O and in order to save a potentially hard or firm landing, pump the side-stick at short intervals in a way that the dual input doesn't sound.

I have never done it, just keep my finger in the red button hoping i don't have to use it.

my understanding according to the algebraic design, is that it would be necessary to deflect ones sidestick beyond the other's deflected amount, to cause an additional elevator response.

what do you think about this underdog common practice?

I call it irresponsible and dangerous. It reminds me of a certain Captain I knew who felt that all that mattered was a super smooth touch down so he wouldn't fully retard one thrust lever so only part spoilers would deploy and hence not dump the front end of the bogey on the 330. Then all he had to do was stop the aircraft before the end, er....

Why not just call "flare" to the FO.

There plenty of auto call outs to cue the flare, vary a little of course with conditions on the day, last thing needed is another unannounced input.

I think this thought originated from incomplete understanding of the system. First thing, even a small movement out of neutral will give a command to change the pitch and depending on what the other stick is doing it will impart the LF or AoA as demanded if other stick is neutral, added if the other stick is moved in same direction or subtracted if other stick is moved in opposite direction. Dual input will sound when the sticks are moved beyond 2°. Once on two consecutive Landings the FO didn't flare at all so I flared at 10ft. and let go. He was happy with the result. I told him you didn't flare I had to flare. He said but there was no " Dual input". I said that's right there was no dual input but the single input was mine. I should have taken priority. The practice of fiddling with stick is senseless will give confusing results. The correct practice ask him to flare or press TO button and do it yourself. There's no follow me on controls in Airbus.

deja vu

My comment of "Why not just call "flare" to the FO" was for those that are worried about the FO flaring late. Not giving an extra call, unless it is required.

It is a common practice in SE Asia. I say "common" but not "right".

It can be called nervous twitch because it doesn't do any GOOD. If it did Airbus instructors would have suggested it. Pilots allowed to give takeoff and landing should be given a practice of take over with the button. It's a tricky part. Instead of fiddling with the stick you need your thumb on the button to quickly take over. As it happened in the Jetstar Australia incident the guy yanked the stick to raise pitch 21° the trainer was unable to intervene resulting in bad tail strike.

You mean like "Oh sh*t"

My understanding is significantly different. The individual deflections are added up, and the sum then fed to the F/CTL computer. Any deflection will have an effect.

A very important aspect is to properly brief new trainees FO/Captains/Instructors on the fact that, unlike other "conventional" aircrafts where a little help is given to avoid digging a hole and spending the turn around with paperwork, on the Airbus FBW family there will be a takeover from the Captain/Training Captain should the need arise, that this is perfectly normal and there is no other way around. In my experience spending a few words with the trainees prior to their first flights and emphasising this aspect has proven beneficial in order to avoid potential demotivation and drop in performances following a low height takeover. It is then up to the trainer/captain to set their own threshold to what is acceptable and what is not according to each own's level of experience, but a takeover is always the right and only option if we are not happy with anything. It is better to have a takeover when it was not really needed than the opposite, and with time everybody can adjust their own tolerance.

Pax so disregard if displaying idiocy. If you were to input little nudges to correct, wouldn't the other guy think he had nailed it and risk embedding a wrong model in his/ her head?

Only if it wasn't debriefed when work load allowed.

FD, algebraically added. Absolutely correct.

But...Isn't that dangerous? Whatever happened to "I have control." I forget how long the take-over button takes, 5 seconds maybe