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Old 18th Dec 2012, 15:46   #21 (permalink)

Dog Tired
 
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Quote:
cool your jets.
You are correct.

Cooled...
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Old 18th Dec 2012, 15:49   #22 (permalink)
 
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Whilst I agree with the above, focussing on the correct touchdown point will more often than not lead to firm landings. At least, that is my personal experience. I changed onto the Airbus with quite a few hours of Boeing time under my belt, but for the first few days of line training I struggled to land the aircraft decently because I was so focussed on the correct touchdown point: the training flights were out of the shortest runway in the network!

My landings and my confidence improved dramatically when I landed on a 3000m runway. Not because I floated the aircraft, which I did not, but because I wasn't fixated on the TD-point and focussed on other visual cues to fine tune the landing!
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Old 19th Dec 2012, 10:51   #23 (permalink)
 
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Flare

Passing the threshold (so, at approximately 50 ft) shift your visual focus point a long way down the runway.
In that way, your peripheral vision will show the descent rate.
Flare enough to almost stop the descent rate.

Do not switch your vision point to inside anymore, because that will destroy the continuity of your descent rate estimation.

My experience is that every landing that was less than soft, I had not shifted vision far enough down the runway, or I did something like a quick check of airspeed during the flare.
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Old 19th Dec 2012, 19:07   #24 (permalink)
 
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PantLoad...
Quote:
At 30feet RA, the aircraft slowly, gradually begins pitching down....a total of two degrees over eight seconds.
True or false?
FCOM says it reduces to 2 degrees nose down pitch over 8 seconds. It never reaches 2 deg nose down because the PF flares for the landing, but that is the "target". So the nose down pitch rate varies with the attitude memorised at 50' RA, hence the importance of being in the slot with the correct pitch at 50'.
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Old 19th Dec 2012, 19:32   #25 (permalink)
 
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What a great thread......! and as you can see from the posts so far - everyone is an expert and everyone seems to do it slightly differently!

The truth is that landing a jet is like most things - the more you do it the more 'innate ' it becomes so that really your sixth sense tells you when and how much to flare. We've all been where you are now and believe me - a 1.4G landing is nothing out of the ordinary and certainly nothing to worry about. I remember in my line training having 1 or 2 that could beat that!

It's also worth mentioning that no matter how long you've been flying and how good you think you are, you'll still thump it in from time to time. I find that just as I'm going through a purple patch and think I've got it sussed, reality bites and I realise I am human after all with a couple of more 'average' arrivals.....

As I say - the important thing is not to worry too much about it and try and learn from experience! Enjoy!

Last edited by Flaperon75; 19th Dec 2012 at 19:34.
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Old 19th Dec 2012, 19:40   #26 (permalink)
 
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btw....

Quote:
Flare enough to almost stop the descent rate
.... was my favourite bit of advice! That's where I've been going wrong!

Flaps
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Old 20th Dec 2012, 01:53   #27 (permalink)
 
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Landing advice

One of the methods I used, was to watch the auto pilot at work during the landing and simply copy it. Remember that mathematics plays a big part in flying and computers. The aircraft normally approaches at a 2.5 to 3 degree nose up attitude on a 3 degree slope. At 15 ft AGL, raise the nose to 6 degrees and lock it there. Simple.
At 50 ft slowly reduce thrust to be at idle at 30 ft. The reason you can do this on hi-bypass engines is because the N1 fan produces 75% of the thrust, so when the thrust is reduced, the free-wheeling N1 (flywheel) fan continues to produce thrust (at a reducing rate). Not like the old straight jets that would reduce thrust to idle immediately, causing you to fall out of the sky. Watch the AP and copy it.
T
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Old 20th Dec 2012, 03:03   #28 (permalink)
 
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Angel Nothing to worry about..

One of the cadets I was jumpseating in my company landed with 1.9G... My physician is still trying to fix the spine..

Good luck with your landings.. My personal experience is dont flare too early, will make you fly 5 feet above the runway.. High weights always make the airplane easier to land, especially if equipped with HGW landing gear, it will behave like an unadequipped teenager, the closer to DOW your LW is
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Old 20th Dec 2012, 03:40   #29 (permalink)
 
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Do not underestimate the fact that a landing is a visual maneuver,you MUST look down the runway to judge your flare input.
By raising your head,your hands should follow by pulling gently until you see no runway rise,you are then parallel to the runway.
If you initiate the flare too early,you will have to flare more slowly and therefore land long.
If you initiate the flare too late,you will need to make an abrupt pitch much may end up ok but can cause positive landing and if with some thrust still in,a bounce.

As mentionnned above , at 50 feet your focus is primarly on the runway as your speed should be set as well as thrust setting.
At 40 feet,the aimiing point will start rising towards you which is the time to lift your head and look 2/3 down the runway and watch the rise.
By the time your head is up,the 30 ft will come and its time to gently pull the nose up WHILE reducing the thrust.
Do not reduce the thrust after you pulled up as it induces long flares/floats,lower pitch at landing and higher vgtd which for your morale is apparently not good.

When the visibility is low ,dark etc all clues should be used including RA and feel of the pants.

Good luck.

Quote:
At 50 ft slowly reduce thrust to be at idle at 30 ft
Come on you cant be serious,do you even know how the autopilot does a landing??
I vote this the worse advice ever.

Last edited by de facto; 20th Dec 2012 at 03:45.
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Old 20th Dec 2012, 11:09   #30 (permalink)
 
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Thank you all very much for the input and for the positive comments.
I am taking everything into consideration and appreciate all the advice given.

Just a few last questions.
Some captains tell me never to look in after 50 feet, some tell me to take quick glances even at 30 to see how you're doing with the ROD, I just wanted to see what you guys have to say about that.

Also, finally, I assume it is normal for a TRI to take the landing from you on your early stages?
It is absolutely the worst feeling when you hear "priority left".
I'm getting comfortable with the aircraft and being told that I am ahead of the game for my level, but I just have a slight issue with the landing, which will NOT be a problem.

I really hope that this is NOT a problem, and something everyone goes through initially till he gets the technique..

Thanks again guys..
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Old 20th Dec 2012, 11:35   #31 (permalink)
 
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I cannot believe some of the crass advice being offered here by supposed professional pilots!

This opinion is based on 16 years on A320/A330/A340 types + 7 years of aircraft base training experience ie. actually teaching people how to land airbus types.

Firstly: emulate the autoland system! This does a very late abrupt flare actioned by rad alt data. Not something for the human pilot to strive for.

Secondly: Thrust reduction - do many of the posters on here realise the relationship between thrust lever angle and thrust delivered whilst the autothrust is in use? From the posters suggestion, I think not! Do not confuse slowly closing the thrust levers with a slow reduction of thrust.

Thirdly: The landing flare has always been a visual manoeuvre - that is exactly why, when the visibility is too poor for adequate visual reference, that autolands are performed!!

That some posters are advocating looking at the flight instruments below 50ft. and making flare references to the ADI horrifies me or perhaps suggests that we have "flight simers" offering their advice!?

Comments from real Airbus pilots welcomed.
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Old 20th Dec 2012, 14:09   #32 (permalink)
 
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Quote:
Some captains tell me never to look in after 50 feet, some tell me to take quick glances even at 30 to see how you're doing with the ROD, I just wanted to see what you guys have to say about that.
At 50 you look out,not in anymore..your rate of descent(closure rate to runway)is by looking at the runway itself...

Im out now,good luck.
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Old 20th Dec 2012, 14:49   #33 (permalink)
 
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To the OP - you should be able to spot the fools here quite easily! As a rated 320 pilot, you will know that bringing the levers back slowly has no effect for the first half of the travel, so any post with slow levers in can be considered drivel...

The answer to your question is in the FCTM and also by listening to a couple of people on this thread.

In preparation, you must be stable and "in the slot" for the last part of the approach. The best way to do this is by visual reference - as a learner you may think that that lovely flight director is useful, but it's not. It's actually easier and more accurate to fly the last part (below 200') using eyes only...

At 30 RA it all starts happening. Stop looking at the aiming point and look now at a point 3/4 of the way down the runway.

The machine starts to lower the nose itself at 30 RA, so even if you wanted to maintain your ROD, you would have to apply smooth and continuous stick-back. But you want to reduce your ROD, so you will naturally apply more stick-back, so apply just a little more such that you see your sink rate reducing and you start to fly towards that point down the runway.

At the very moment your nose goes up, the thrust will increase (to maintain speed). This is a bad thing because, despite the theory, there is still a tiny pitch-power couple. So the solution is to cut the thrust a millisecond after 30' and to do this you need to promptly close the thrust levers (subject to abnormal speed variation).

And now all you have to concentrate on is the stick and the new aiming area. You continue to gently pull back, so that you are visually using texture flow to fly the aircraft towards that point positioned 3/4 of the way down the runway. This will give a small ROD and a tiny bump at touchdown.

In summary:
  • Stable approach.
  • Visual references only below 200'.
  • If slightly off target, correct only in small amounts so as to not affect stability.
  • At 30' start a gradual stick back and...
  • Close the thrust levers promptly.
  • Continue the stick back until you are flying to a point before the end of the r/w.
  • Done.
  • For a crosswind, move the pedals as slowly as is humanly possible. So you may have to start that really slow movement as high at 25 RA. When you get the hang of that, halve the pedal movement speed.
HTH
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Old 21st Dec 2012, 02:20   #34 (permalink)
 
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de facto, I gave the reason why you can do this. Did you read it? I did that for years on the 320 with no problem, why? because I understood how the by-pass engine works. You don't have to do it, no one is twisting your arm. It's a matter of choice.
T
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Old 21st Dec 2012, 17:55   #35 (permalink)
 
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Please read it again....

Again, and as usual, I emphasize the need to read
your SOP, the FCTM, the FCOM, etc., for yourself.
Then, there should be no confusion.

With regard to the two degrees in eight seconds...
I suggest that this be read again, for clarification.

I understand that, for many, English is not the native
tongue. So, reading from authoritive documents that
are written in English is a challenge itself.

If there is any question, I strongly suggest that you
contact someone in your training department. While
I love PPRuNe, I find much of the writings, here, are
complete nonsense.

Fly safe,

PantLoad
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Old 21st Dec 2012, 22:25   #36 (permalink)
 
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Serious question. As a retired rotary pilot, I have no experience at all of landing jets. I was kinda surprised to hear that it's all done by numbers, at 30ft do this, at 20ft do this. How would you manage if the rad alt failed? Is this not taught in training?
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Old 21st Dec 2012, 22:55   #37 (permalink)
 
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RA callouts are helpful. We're talking of eye heights over 20', and maybe 30', at touchdown. Are they necessary? No.

Don't look inside below 50'? If you've got quick enough scan and want to look at something go ahead. I often glance at the RA readout, even during the flare.

Maybe shifting your gaze avoids fixation and is helpful. IDK but it works for me.
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Old 21st Dec 2012, 23:31   #38 (permalink)
 
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It isn't that complicated. Fly the approach or visual, flare using visual reference, smoothly reduce power and touch down. You can see how high you are so why bother with listening for a RA altitude? Fly like a pilot, not a robot. Automation has taken flying skills away from pilots in a lot of cases. I never let it happen. My Aeronca Champ didn't even have a battery installed so automation dependency was not a problem.

Flying the B757 to Tegucigalpa, Honduras was all visual approaches below 2700 ft with terrain all around and a hill that required the final turn to final be at 100 ft. Fun flying but you had to be a pilot, not a pilot mill graduate.
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Old 22nd Dec 2012, 07:58   #39 (permalink)
 
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Meikleour you come across as someone who knows what he is talking about (fantome your input would also be welcome). What would you recommend when landing an A321 not too heavy with a light quartering tailwind that gets a sink rate that requires the thrust to be kept at the CL detent until the wheels collide with the tarmac? Short of a go-around it is still got me stuffed as to what actually happened. What would you think of bringing the thrust levers back to mid position between CL and IDLE and disconnecting the A/T just prior to runway contact? Serious question.
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Old 22nd Dec 2012, 14:08   #40 (permalink)
 
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Lookleft: Thank you for your kind words however I have never flown the A321 only the A319/A320 variants. A rare moment of honesty not always evident on PPRuNe perhaps?!

However....... anecdotal evidence from talking to colleagues who have flown it suggests that the situation which you describe is much more common with the A321 than the smaller variants. Remember, the wing is essentially the same area but lifting a much higher weight. In addition the TE Flaps are different.
The most common advice would seem to be to ensure that there is a truly adequate margin between Vls and Vapp whilst using ATHR.
Your suggested technique is too vague since you would have no real idea of how much "extra" thrust would be delivered and the time taken for it to be delivered. The +5kts increment when using ATHR is to compensate for lag in ATHR response. If you were to use manual thrust no such padding is necessary and thrust response more immediate. Therefore the aircraft should be fully "flareable"(?) at Vapp provided that it is judged correctly.

In the situ. you describe, if the wind really is that light then I suspect that you are just flaring very slightly too late and/or too abruptly.

I have always found that whilst the A320 uses a normal flare the much shorter A319 simply needs a "check" prior to touchdown.
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