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LEM
12th Jun 2003, 06:22
Some captains let the copilots do hard landings without intervening (within acceptable limits, of course, but still very very firm!).

Do you think they are useful experience to the FO, or only unnecessairily harm their pride?
(BTW, I think passengers always deserve good landings...)
:uhoh:

Golden Rivet
12th Jun 2003, 09:19
You might think twice if you had to do the Hard landing Inspection Afterwards !

Maxrev
12th Jun 2003, 15:49
I don't know about useful, but taxying into stand with all the duty free bottles rolling around the aisles after you've just popped open all the overhead lockers with your ham fistedness is not something you'll want to repeat.

We all aim to get it on as smoothly as we can, but remember that you don't always have the luxury of a long, long runway with a steady breeze coming straight at your nose.

If the runway's wet for example, you'll be aiming for a 'positive' touchdown to give you plenty of room to stop. Any fool can float the thing to a featherlike touchdown as long as you don't mind a stroll through the grass to get to the terminal after you've run off the other end.

Also some aircraft give a smoother landing than others anyway - especially those with trailing gears. The VC10 was famed for soft landings and I've always found the 747 to be the same.

HOMER SIMPSONS LOVECHILD
13th Jun 2003, 05:55
LEM, it depends on your definition of a "good" landing.What the passengers (and cabin crew) consider "good" is actually a SOFT landing.The fact that it was halfway down the runway,off speed,off centerline,wrong rudder,innapropriate for the rain,just lucky etc etc etc never enters their heads.
A "good" landing is on the TDZ, on speed ,on centerline,aligned and without bending the aircraft.The outcome on the day for many types when all the above is either firm or a greaser.Thats often a question of luck,or the slightest of differences.Both will be "good" landings.
You have probably never encountered a true "hard" landing which requires a check.I've absolutely stuffed the Boeing in a few times (I'm Captain BTW!)and it was never anywhere near the limit.If it is truly heading for a "piano landing" I'll jump in but I'd never ruin a good clonker! Nobody ever ruined mine.
ps,as a pilot you are only as good as your last landing-ask the Hosties!:\

akerosid
13th Jun 2003, 06:13
Nine out of ten dentists recommend them! Nothing like a few loose molars to drum up business.

Seriously, though, I would imagine that if you made one and providing there was no damage to the aircraft (which might result in retirement plans being brought forward a tad), you have to take a lesson out of it.

Why did it happen, what could I have done to prevent it, could I have seen it coming, etc.

Max Angle
13th Jun 2003, 07:13
To be honest there is not much the other pilot can do about it. By the time the flare hasn't happened it is too late and a pile driver is going to happen no matter what. In some types a last minute tug on the stick can actually make things worse by rotating the main gear into the ground.

Only one thing is certain, no matter how experienced you are they still happen, they may get rarer but no one is immune. I must be due one coz it's been a while now!.

LEM
13th Jun 2003, 16:42
I agree, of course, with all of the above, but often an excessively firm landing is really not required (long,dry rwys).

Personally, I'm considered a bit rude because I intervene (not by declaring "I have control", but by "helping" on the yoke) almost always as soon as I have the feeling that the FO is going to make a bad landing.

This for two reasons: I think it's not necessary for the FO to learn by the hard way when it comes to landings, and second because passengers deserve an acceptable one.

Other colleagues of mine purposely let extremely firm landings to happen because, they say, it's a good lesson for the FO.
But from the passengers' point of view it's very, very, very bad!

It's a different story on the Airbus, where the captain won't be considered "rude" if he "helps" on the joystick.
I'm told on those airplanes the FO never really knows if he made the landing or not!
Comments from fbw Airbus pilots wellcome!

52049er
15th Jun 2003, 08:31
As an Airbus FO there seem to be two types of capt - those whose left hand stays on their knee, and those whose left hand strays towards the stick (amazing how wide your peripheral vision can be :)

The maj are in the former - but it doesnt bother me either way, after all, its his signature. Intervention on ldg is a much less frustrating thing than constant, unasked for and unmonitored fiddling with the fcu during descent for example, which is just bleedin rude if you ask me (not that its happened recently and Im still sore of course.......)

LEM
15th Jun 2003, 14:47
Interesting, 5209er, I thought it was standard in all companies for both pilots to land with their hand on the joystick, to be ready just in case....
Just curious, what do they teach in Toulouse?

used2flyboeing
23rd Jun 2003, 07:47
If I recall - Boeing training used to make a point of "CRISP" landing procedures as opposed to "HARD" landing & "GREASED" landings. There have been several incidents due to pilots greasing the airplanes on Sooo smooth that the air-ground logic gets confused & the airplane never gets into a "GROUND" mode where you got spoiler & thrust reversers. Recall that the air-ground sensors for these systems are inductive or magnetic prox-sensors - who in my opinion need a sharp transition - recall the levels of protection on these systems - IE spoiler & reversers on final are somehing A/C mfg's go to great lengths to avoid in the air - particularly on final for obvious reasons - therefore when in doubt - lock it out. With the advent of high thrust twins such as the 767-300ERs - pilots were performing aircraft carrier landings - slow with lots of angle of attack to grease these birds on the runways - of course this also exacerbated the occurrance of tail strike as well - morale - you should always follow the manufacturers procedure - which I think is a "CRISP" transition from air to ground - I leave that up to you research more .. IE something between popping stowage bins and ....

Regards,

RadarContact
23rd Jun 2003, 16:40
LEM:
I do see your points, but how and when exactly do you decide the FO is going to let it drop?
There sure are a lot of different landing techniques out there, from initial breaks to last minute firm rotations. I'd personally rather have you take control and talk to me later about why you felt it necessary than regularly gently "autorotating". Latter does confuse a lot if one is not prepared for it. Maybe you should trust your right-seaters a bit more? ;) Because, yeah, they also do like to make soft landings...

As to the Airbus: You sure can`t feel the other CM intervening with the sidesticks, but dual input is certainly displayed and announced immediately!

LEM
23rd Jun 2003, 18:12
I was told by Airbus pilots that during the flare sidestick inputs are additive, with no indications at all, unless the takeover button is pushed. (like nwsteering on the ground).
Is that correct or not?:confused:

SLT
23rd Jun 2003, 18:13
LEM,

To answer your question, it is standard for ONE pilot to fly the aircraft, while ONE pilot monitors. This aeroplane has been designed to be flown by one pilot or the other - period. Dual inputs CAN be made, but usually cause more problems than they cure. We've all done firm landings in our time, but never have been near the limit. As has been said already - don't confuse a "good" landing with a soft one that's in the wrong place!

Give the Airbus wind-ups a rest, it's getting boring now. :rolleyes:

LEM
23rd Jun 2003, 18:30
To answer your question, it is standard for ONE pilot to fly the aircraft, while ONE pilot monitors. This aeroplane has been designed to be flown by one pilot or the other

Of course, like all other airplanes.
But this does't answer my questions:

Again, if during the flare dual inputs are made without pushing the takeover button, is there a visual/aural indication?

On a conventional aircraft, one pilot lands and the other monitors, with his hands on his laps.
On the Airbus the NON flying pilot keeps his hand on the stick, or not?

I'm not criticising here, just asking.
If you got bored, just go to another thread.

HotDog
23rd Jun 2003, 20:02
LEM, which version of FS 2000 are you in command of?:(

FlightDetent
25th Jun 2003, 21:08
Letting FO hit the ground crispier than (s)he intended is definitely not a lesson learned THE hard way. That comes when CM1 or training captain to any pilot intervene on landing. This way the trainee never gets the idea which was the response of the airplane, which was the response from PF's inputs nor which was the PNF's "help". No matter how thorough the de-briefing would be.

I do only have 21 landings under line trainng on 737 but I am sure that underlines my point.

LOVECHILD, yours shall be craved to stone. :ok:

The last lainding I made was ultimately the greasiest of them all, scored only 1.11 g which is actually about half of what we get on short final over the highway or when the nosewheel hits the centerline lights (yes, the sensor is located somewhat closer to the sharp end).
And although perfectly safe, with autobrakes set to 1 there was no turn-off braking needed and about 900 m still remained, it simply was not a good landing. I managed to waste about 300 m on the flare compensating too late for the lighweight loading (20pax + 2t RSV fuel on -500) and the gentle downslope, touched down with tiny right bank, almost two body lenghts right of the ceterline with crossed controls under what was no relevant XWC at all (3kts). I was stunned how tricky the handling in ground effect can get at Vref 114kt. Thanks almighty, there was no crabbing, otherwise you probably couldn't screw up much more. Still, at 50', we were precisely where were supposed to.

That was a good lesson to learn. Had the captain at 30' held the control column down for two seconds and then said "Idle now!", it would have been a good and neat landing but close to zero instruction. I am very glad it was the other way 'round.

Geardownandlocked
25th Jun 2003, 23:03
It is a horrible thing for a captain to intervene during a landing. Do captains never make hard landings? What would he feel like if the fo would regularly just 'help' him a bit on the landing...

Let everybody do their own flying, you learn by doing yourself.

Just wanted to say that...

LEM
25th Jun 2003, 23:18
It's natural that our debate comes to this point, anyway I was thinking only to horrible landings! :oh: :ooh:

leftseatview
26th Jun 2003, 01:10
i just mention who is flying that particular sector ,during my welcome annoncement to the PAX,then sit back and let the F/O fly the machine.
Most do an great job knowing that the only intervention i'll make is call for a "Go-Around" if things get hairy.
Only problem can be in case of a bounce,in case the bounce sends you up to circiut altitude join left or right as appropriate!
if not lot of fast juggling recuired!!
Happy Landings!

RadarContact
27th Jun 2003, 05:18
LEM: I've experienced dual inputs at touchdown. They were definately indicated.

LEM
27th Jun 2003, 16:59
Ok, just to satisfy my curiosity, if it's not asking too much, could you kindly,please , tell me what kind of indication you get in case of dual inputs during the flare?

Why did a LH Captain, me on the jumpseat, tell me that the copilot never really knows if he mede the landing?

Again, just curious, not criticising!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! !!!!!!

RadarContact
27th Jun 2003, 22:16
Assuming this took place on an Airbus, it would still be interesting to know what type of Airbus.

If the additional input is very short, there will be an optical indication on the glareshield in front of the pilots which, unfortunately, one is likely to miss in high workload situation. Only after that will an acoustic warning be given. I'm not really certain about the amount of time, I'd have to look it up. But I'd guess it to be a little less than 1 sec.

That's for the technical side.

On the other side, I wouldn't take such a comment too seriously. The Copilot not noticing or not complaining about it are two different things...

LEM
28th Jun 2003, 04:33
Hmmmm... Is that indication "Priority left"?

RadarContact
29th Jun 2003, 01:19
No, it is "dual input".

It's included in one of the newer FWS standards. Aircraft with older FWS standards will receive only the visual warning.

Ignition Override
29th Jun 2003, 13:49
used2flyboeing: were you indirectly refering to the tragedy at a Polish airport? The Lufthansa First Officer died after the 'advanced' aircraft landed either very long, maybe with a strong tailwind, on a wet runway, and because the main wheels barely rotated, the "advanced" software logic prevented all of these functions:

1) thrust reverser actuation
2) ground spoiler extension
3) auto/manual braking (probably negated anyway by antiskid transducers on a hydroplaning machine).

The plane must have had a better chance of landing and stopping after the "advanced" software was redesigned to somehow function differently. Good guess- " " denotes either irony, not so subtle sarcasm, or both. Would not a superior set of aircraft systems allow a human pilot to quickly control and lift levers and deploy spoilers plus reversers.? :hmm:

LEM
29th Jun 2003, 17:18
Would not a superior set of aircraft systems allow a human pilot to quickly control and lift levers and deploy spoilers plus reversers.?
On that so called superior aircraft that was apparently not possible.
On a B733, for example, you can deploy reverser in the air below 10ft - although formally prohibited.
That means in that circumstance the pilot would have been able to deploy full reverse, even if the airplane was still in the "air" mode.
You also have a real speed brake lever, just pull fully and you'll get at least full flight spoilers.

When it comes to antiskid, it's an invaluable aid , but still it's something between our feet and the brakes, it's a device which filters our intention of braking -> if it f##ks up, it can do more harm than good: we must be aware of that, as demonstrated by numerous incidents/accidents, and be ready to turn it off promptly.


http://www.airdisaster.com/photos/lh2904/1.jpg

slingsby
29th Jun 2003, 18:06
http://www.jetphotos.net/viewphoto.php?id=193

Comments?

LEM
29th Jun 2003, 18:29
Sligsby, I don't see your point. Maybe you mean that couldn't happen in an A320?

VR-HFX
30th Jun 2003, 12:09
LEM

Firm on the aim point is always better than a floater, X-wind or no X-wind.

Any intervention should happen well before the outer marker. If the a/c is set up properly then keep your hands off ( and your trap shut) unless you see things getting dangerous at which point it is a go around.

Where things go wrong these days is that people get used to 12,000 ft of bitumen and forget Rule One. Then one day they get a short runway a la 16L/34R at Narita (2,180m) and end up in the grass.

Ignition Override
30th Jun 2003, 13:06
LEM: quite correct and good points. Even our turbofans built in the 60s have anti-skid, armed by one small switch plus having the gear handle down (+ normal AC and DC power).

tykon
1st Jul 2003, 16:12
To used2flyboeing,

Yes, you're correct about the magnetic sensors etc, near/far, all that crap....BUT...it doesn't make an ounce of difference if you touch softly, or dump it down. The sensors are set into ground mode, or air mode, when the torsion links on the gears compress or extend. There is no thinking in the system, either it is on the ground or not. On the B737Ng, there are 2 sensors on each gear, and between them they work out if the aircraft is still in the air, on the ground or back in the air etc. All the sensors go to the PSEU to be sorted out.Depending on the combination of gears that are compressed/extended, as to what it allows to happen with the anti skid/aquaplaing and so on protection.

Fil
1st Jul 2003, 18:59
Someone asked about Captains making extra control inputs on Airbus's

There are two similar occasions, (EI and LH I think but please don't shoot me if I am wrong) where (both in A321's where the tail is much closer to the ground than the 319/320) the FO was flaring too late or too little. Both times the training captain in the left seat added his or her own stick inputs AT THE SAME TIME that the FO corrected his or her own mistake. Both resulted in tail strikes.

I believe this has been discussed here on PPRUNE at some depth but I don't know where.

I'm not saying that Captains should not make stick inputs just repeating what has happened when the Captains input didn't go according to plan. Oh yes, one important fact I nearly forgot was that on each occasion no mention (or 'I have control') was made that any additional inputs had been made.

Pegasus77
2nd Jul 2003, 01:53
Hello mr. LEM,

1. If you were my captain, and I was PF... would you please call for a go around before you start "helping", so neither of us knows who is steering what?? That's about the basic of basics in the crew concept! If you would "help" me in case you expect my landing to turn out to be firm... we would end "am grünen Tisch", where you may try to explain why you didn't stick to SOP and therefore greatly endangered the flight.

2. If, on an A320, the captain decides to "help", the FO has a flashing green light in front of his nose, so he will notice. This captain you met when you sat on the jump was not telling the truth. My guess he tried to look like just a real true airman as you are (which he obviously is not).

3. Is it IYHO also possible for a captain to make a hard landing? Or do you think the FO is not capable of taking over controls and saving the day, when needed? Your question only refers to the captain take correcting action, I have seen many bad landings made by the LHS.

Regards,
P77

TopBunk
2nd Jul 2003, 02:24
To answer the original question: are firm landings good?

Yes - to remind the passengers how lucky they are when they get one of the 'smoother' ones;)

LEM
2nd Jul 2003, 03:28
Come on, guys! I know very well all the above....
Our company is not a major one, and we have somevery
inexperienced FO.
Some of my colleagues let them do extremely hard landings, sometimes.
I think this no good.
It's not a training flight, we carry paying passengers, for Christ sake!

slingsby
3rd Jul 2003, 17:45
LEM, sorry for the delay in replying, but this KLM flight was training FO's in Oostend, better to get landings like this out of the way in training rather than on the line. Any kind of landing is possible in any aircraft, just that this one was rather abrupt and caught on camera. Just a bit of enlightened humour.

LEM
3rd Jul 2003, 22:50
Better to never get a landing like that! That was quite close! Tha captain should have intervened earlier, even if it was a training flight!
Scraping the wing would not have been a nice lesson to the FO...

Cough
3rd Jul 2003, 23:28
LEM... Point being is you need to let them practice. Remember todays F/O is tomorrows CAPT. If you don't let them practice putting it down right place, right speed, ask yourself this: How comfortable are you going to feel when positioning, with them now as CAPT, to somewhere with grotty wx and a short runway, having taken away all their practice?

Heavy landing are one thing, firm ones are acceptable. By the sounds of it you may need to chill a little.

Second point. I have been in the RHS when we had a voilent wing drop in windy weather, experienced training Capt as P/F. I saw where the control column went (correct input) and we landed something like the cloggy 737. Its not nice, not pretty but it happens. How do you know that the Training Capt hadn't taken over as a demo circuit and that happened?

LEM
4th Jul 2003, 03:42
Years ago, I made a very bad landing- quite hard - bounced - scared passengers....
I would have preferred the captain to "help" a little bit to avoid that, just as little as necessary not to make it so bad, and then give me a good explanation of optical illusions on narrow runways.
There are plenty of other occasions to practice and to learn...

One of my ex-bosses crashed during a NDB approach a few years before joining our company... airplane destroyed, no injuries thanksgod.
Do you consider that to be a useful experience? Wouldn't have it been more useful to have a good instructor really teaching (verbally and with actual example) how to fly a nonprecision approach?

There are many handling accidents which could have been avoided if the copilot had not been flying.
The typical captain's answer to the investigation people was: "Well, it was the copilot's leg, I figured he knew what he was doing..."

In the past, the difference in stature between Captain and copilot was enormous.
The Tenerife accident changed all that. Now our culture has shifted from one extreme to the other.
Many captains are afraid to intervene, when they should do so, to avoid harming the copilot's feelings...
There are many accidents to prove that. One of them is the Delta crash in Dallas Forth Worth, in which the captain still did not take over when it was clear they were in dire trouble....
and the list is long.

Cough
4th Jul 2003, 17:28
As I said lem, there is a great difference between a heavy landing, and a firm one in the right spot.

The first time a pilot makes a difficult landing should be with suitable supervision in the RHS, not after he has passed his line check and alone in the LHS.

used2flyboeing
6th Jul 2003, 01:36
TYKON SAID:
To used2flyboeing,

Yes, you're correct about the magnetic sensors etc, near/far, all that crap....BUT...it doesn't make an ounce of difference if you touch softly, or dump it down. The sensors are set into ground mode, or air mode, when the torsion links on the gears compress or extend. There is no thinking in the system, either it is on the ground or not. On the B737Ng, there are 2 sensors on each gear, and between them they work out if the aircraft is still in the air, on the ground or back in the air etc. All the sensors go to the PSEU to be sorted out.Depending on the combination of gears that are compressed/extended, as to what it allows to happen with the anti skid/aquaplaing and so on protection.


..all that crap..., does make an ounce of difference if you understand how the system is designed .. I was more speaking to 75 & 767 that use truck tilt sensors in addition to squat switches - Boeing has gone to great lengths to work out ground logic based on in service problems - IE the non-uniform piloting / landing techniques the world around have never failed to confound the logic of the PSEU system. Boeing has used a permutation of truck tilt, MLG & NOSE Gear squat switches & even Inertial reference to sort this out. I know the 757s with the 13 degrees of truct tilt - would pop out of ground mode if you did a bounce on landing - & guess what, it would pop out of autobrakes as well ! On some 737s if you did a very smooth landing you would not get any spoiler or reverse thrust b/c the PSEU could not detect a disticnt transition - all this stuff has been fixed - but the result at Boeing Flight Training - at least back in the early 90's was to do crisp air to ground transitions ..