PDA

View Full Version : Pod Scrape at LHR


Captain Rat
3rd Nov 2005, 17:05
Seems the windy conditions got the better of one 747 this morning at LHR with a number 1 engine pod scrape on landing....

Carnage Matey!
3rd Nov 2005, 17:49
Whose the culprit?

Warped Factor
3rd Nov 2005, 18:13
Whose the culprit?

Whoever decided to close 23...

WF.

JW411
3rd Nov 2005, 19:48
I could not have put it better but the damage is unlikely to come out of the BAA budget.

411A
3rd Nov 2005, 21:21
Here we go again.

Lets see.
The airport is responsible because 23 is closed.

What claptrap.

IF the handling pilot cannot land the aeroplane with a decent crosswind component, they should be assigned to a ground job where, all things considered....they belong.

Hey, they accepted the job, passed the checks, and if they canNOT cut the mustard, they should get a don't come Monday letter.

BOAC
3rd Nov 2005, 21:31
Let's hear it again for the 'wing-down' boys.....................:D

newt
3rd Nov 2005, 21:35
Here we go again. Judgement before the facts are known!! We all make mistakes and it is unfair to be so critical at this stage in an open forum. Try to think how you would feel if it ever happened to you! GIVE THE GUY A BREAK!!!!

wingman863
3rd Nov 2005, 22:23
411A; while you have the bones of a valid point, everyone does make mistakes and to say the pilot should be assigned to ground duties is to say that anyone who has ever had a tiny shunt in their car should have their driving license revolked. A tad stupid methinks.

Farrell
3rd Nov 2005, 22:45
IF the handling pilot cannot land the aeroplane with a decent crosswind component, they should be assigned to a ground job where, all things considered....they belong.

You have to hand it to 411A though. He is one of the best putter-downers on this forum. ;)

Doors to Automatic
4th Nov 2005, 00:52
Was the landing in question on 27R by any chance?

Witraz
4th Nov 2005, 05:52
411A writes
What claptrap.

IF the handling pilot cannot land the aeroplane with a decent crosswind component, they should be assigned to a ground job where, all things considered....they belong.

Hey, they accepted the job, passed the checks, and if they canNOT cut the mustard, they should get a don't come Monday letter.
Again jumping in with both feet. Ever looked at the record of pod scrapes on the B747. Get the right configuration and wind, it happens. I feel sorry for the crew. Guess like the last time they will get the talking to, six crosswind landings in the simulator and be back out on line. Not sure I would like to share a flightdeck with someone as perfect as 411A. Could be dangerous.

Farmer 1
4th Nov 2005, 05:57
Here we go again. Judgement before the facts are known!! We all make mistakes and it is unfair to be so critical at this stage in an open forum. Try to think how you would feel if it ever happened to you! GIVE THE GUY A BREAK!!!! 411A; while you have the bones of a valid point, everyone does make mistakes and to say the pilot should be assigned to ground duties is to say that anyone who has ever had a tiny shunt in their car should have their driving license revolked. A tad stupid methinks. 'No, no!' said the Queen. 'Sentence first - verdict afterwards.' Lewis Carroll

christn
4th Nov 2005, 06:20
Those that can do, those that cannot sit at home and make silly comments on PPRuNe!

Captain Rat
4th Nov 2005, 07:48
In answer to a previous question, yes it was 27R, could that be why they seemed to be using 27L for the rest of the day (no change over at 3pm as normal. (May have been other reasons?)
As to which airline involved, I think nothing is gained by naming it.
Regardless of pilot skills, the fact is that if 23 was still available then the chances are this wouldn't have happened. As previously said, I'm sure the BAA wont pick up the repair bill, but I'm sure closing the runway has saved a few pounds...

Del Prado
4th Nov 2005, 08:07
When the wind is strong from the south west it is standard practise to use 27L for landing due to turbulence from hangers on approach to 27R. this incident had no bearing on de-alternation.
The problem is that a strong SW wind gives a stronger headwind component. The landing rate suffers as a result, so delays go up.
Then we use the departure runway to land an extra 6 per hour (TEAM). I believe the aircraft yesterday was allocated the departure runway (27R).

Maybe if there wasn't so much pressure put on the landing rate by airline management we wouldn't be exposed to these risks.

Onions
4th Nov 2005, 08:50
All this is all very well but who's was it?

A37575
4th Nov 2005, 10:12
411A is saying nothing that the silent majority of Pprune readers reading this thread don't already think. Too often, cocked up crosswind landings are the result of incompetent handling so why shy away from saying it? And why be so coy of naming the airline concerned? Political correctness gone mad again?

Artificial Horizon
4th Nov 2005, 10:23
Hey these things happen, it was at times a pretty awful day weather wise yesterday. We are all just a tiny slip up away from similar things happening. I don't feel that it is very useful to be critical of the pilots before all of the facts are known. Just hope I am lucky enough that I avoid this sort of incident in my future!!!

GOLF-INDIA BRAVO
4th Nov 2005, 10:40
I`m not aircrew but we all know what a cross wind can do if it is gusty and not only with planes

I was on a double desk bus going up the M4 to Heathrow a few years ago and it was caught by a cross wind and blown right across three lanes and the driver only just managed to catch it before it hit the central reserve
I was on the top deck at front and it scared the living daylights out of me

G-I-B

alexban
4th Nov 2005, 10:42
met conditions at the time-wind aprox 200deg with 25-36 kt ,more or less. Our flight,landing some time later on 27L had encounter strong windshear bellow 100' .I only imagine what was like landing on that conditions on 27R ,with the turbulance given by the hangars...some great show for the guys on the airport to watch..:}

blueloo
4th Nov 2005, 11:01
411A - you love fishing dont you.



Why not wait for the report. This was a pod scrape in Perth a while back. According to the report the handling pilot did eveything within his powers correctly, the aircraft ran out of roll control. Mother nature won.

Del Prado
4th Nov 2005, 11:16
This aircraft landed on 27R despite the turbulence from the hangers. wasn't there a similar incident a couple of years back when an aircraft (same type) ended up on the grass?

CarbHeatIn
4th Nov 2005, 12:18
Challenging conditions at the best of times, even more so after a long over night sector. Interesting to see the driver's recent roster.

PAXboy
4th Nov 2005, 13:47
Pax perspective: The flight crew got the machine to the gate without anyone being hurt. Sounds like a good result to me.

SMOC
4th Nov 2005, 14:08
A little off topic, do VS have F/O X-wind limits? Personally I hope they don't.

egbt
4th Nov 2005, 14:40
Agree with PAXboy,

I PAX’d in late yesterday afternoon on a 737 to LGW, a good landing in the end, but lots of wind sheer and turbulence most of the way in. Bet the captain was also a little tense with the FO as PF.

Way over my x-wind limit.

behind_the_second_midland
4th Nov 2005, 15:52
Del Prado

When the wind is strong from the south west it is standard practise to use 27L for landing due to turbulence from hangers on approach to 27R. this incident had no bearing on de-alternation.

I'm afraid you are wrong in some of what you say.

I've been flying all week and landing on 27L after 3pm.

Yesterday when we landed before 3pm it was on 27L along with everyone else.No-one was landing 27R yesterday afternoon when I was around. It should have been 27R (up to 3pm) under normal circumstances so something caused the change, I suspect it was the pod scrape.

Doors to Automatic
4th Nov 2005, 15:52
SMOC/EGBT, as I understand it most airlines will limit an FO to a low crosswind until they have a certain number of hours.

So an FO handling an aircraft at or near it's limit will be an experienced one.

behind_the_second_midland
4th Nov 2005, 15:54
In BA FO's have 2/3rds the aircraft limits on all types.

There are no varying degrees, its 2/3rds for all from day 1, or you don't make the line.

Obviously the captain has to use his judgment as to the experience of the FO, but in theory its from day 1.

Incidentally I let my FO land it yesterday up to his limits with windshear and turbulence under 100'. Did a great job as I knew he would.

Del Prado
4th Nov 2005, 16:53
behind_the_second_midland,
sorry, I never seem to make myself clear on these boards so just to clarify,

You're right, in normal circumstances it should have been 27R before 3pm, 27L after. However in strong SW winds it is known that turbulence is created by the hangers and so 27L is always used when the crosswind is above a certain limit.(I won't quote the figures in case I get them wrong!)

Yesterday morning because of the wind 27L was the nominated landing runway, I believe the aircraft in question landed on the departure runway in accordance with the TEAM procedures used to tactically enhance the landing rate.

The landing runway was not decided because of the pod scrape but because of the existing crosswinds.

Ps. hope it wasn't a case of sod's law for you when the very day you get 27L , you end up parking at Terminal 1 ?

;)

CCA
4th Nov 2005, 18:03
CX crosswind limit:

JF/O - 10kts
F/O - 15kts

However Base training & training Captains can up the limit.

JW411
4th Nov 2005, 18:17
In my company the F/Os have exactly the same crosswind limit as me - 35 knots. It is usually better to let the youngsters get on with it. It is good for their confidence-building and they are mostly better at it than me!

Don't pay any attention to 411A. The miserable old curmudgeon comes from the L-1011 which was a wing down aeroplane and, as far as I am aware, he has zero time on the 747 landing in a 35-knot cross wind. The 747 is a "kick-off drift" aeroplane (for very obvious reasons).

behind_the_second_midland
4th Nov 2005, 19:33
Del

Understood, thanks

BTSM

Lou Scannon
4th Nov 2005, 19:38
I flew a variety of aircraft in a variety of crosswinds over the years and always tried to get in rather than have to divert.

I didn't scrape anything but must have been very close to it at times.

From the safety of retirement I have every sympathy for the guy that did nick a pod at LHR. I trust that his company will accept that pilots do their best in these conditions.

The alternative is to divert anytime the gusts look even slightly above the limit (say just once in the last fifteen minutes).

No one wants that.

egbt
4th Nov 2005, 20:13
Doors to Automatic

As I think was clear in my post I had no problems, but I hate other people driving me in a car and if I had been the captain yesterday I'd be trying not to show the white knuckles when my No 2 was flying – but I’d let him do it as I know about delegation, confidence boostingetc etc (I could never be a FI!).

Unfortunately my little a/c (shared) has a 13 Knt demonstrated X-wind limit which rather put the kybosh on my planned trip today but it was fun landing at the home base at 2/3 the normal speed over the ground.

CAT MAN
5th Nov 2005, 09:12
The morning in question was interesting, I caught sight of the 747 at about 2 miles on final 27R. The aircraft had a significant amount of drift on, as it appeared from my position, perhaps (15-20) degrees.
It was quite early in the morning and the holding point on RW27R ( the departure RW) had several aircraft in situ unable to depart due to SIG WX to the north of the field.

The 744 continued its approach and appeared stable all the way.
The ROD was checked and the drift kicked off beautifully, but the mains went on fairly solidly followed almost immediately by the nose.
To my horror I caught sight of the no 1 pod make contact with the ground. The aircraft continued along the runway and vacated out of my view. A couple of a/c reported the incident over the R/T.

I have been to LHR on more than one occasion.
On the day in question (Thur Nov 3). The turbulence on approach gave rise to conditions that the typical short haul operator might encounter on only a couple of occasions a year.
Tower reported wind and GPS wind just 100' above the RW were significantly different.
On a later approach to LHR wind display at 200' gave the wind as 200/36 when the tower was reporting 210/19.

Have no doubt about the conditions the crew experienced...

From my front row seat the a/c was stable throughout the approach...But hey there but for the grace...go we all.

ratarsedagain
5th Nov 2005, 10:32
Del Prado,
wasn't there a similar incident a couple of years back when an aircraft (same type) ended up on the grass?
The incident you mention was very different in that it wasn't turbulence off the hangers, but the fact that it encountered a gust exceeding the limits of the aircraft as it came out the lee of terminal 3. (and yes the wind was in limits when they landed)

behind_the_second_midland
5th Nov 2005, 11:02
On a later approach to LHR wind display at 200' gave the wind as 200/36 when the tower was reporting 210/19

The last 200' were a wee bit tricky on Thursday!

barit1
5th Nov 2005, 11:53
I once rode in back of a TriStar into AMS - there was teethjarring turbulence (note to self: great alliteration!) all the way down the approach to about the last 100' - whereupon the F/E finally found the "Cancel Turbulence" knob and we touched down smooth as glass.

Never witnessed this phenomenon before or since.

flown-it
5th Nov 2005, 14:58
Off the topic slightly..and my apologies if this issue has been raised before. But why do some pilots (I see it all the time in military pilots of non UK origin) transition way out to the wing down cross contol technique? Uncomfortable for SLF . So kick it off and plant it says I! It appears this is what they did and the gods where just not with them. Wonder what a wing down , boot full of right rudder approach would have been like in the same situation.

GT3
5th Nov 2005, 15:01
You're right, in normal circumstances it should have been 27R before 3pm, 27L after. However in strong SW winds it is known that turbulence is created by the hangers and so 27L is always used when the crosswind is above a certain limit.(I won't quote the figures in case I get them wrong!)

Yesterday morning because of the wind 27L was the nominated landing runway, I believe the aircraft in question landed on the departure runway in accordance with the TEAM procedures used to tactically enhance the landing rate.

The landing runway was not decided because of the pod scrape but because of the existing crosswinds.

Ps. hope it wasn't a case of sod's law for you when the very day you get 27L , you end up parking at Terminal 1 ?

Erm... I'm afriad the above is incorrect. The daily alternation is changed every Monday morning. So week 1 would be 27L landing until 3pm local then 27R for landing after that. The next week will be 27R for landing in the morning until 3pm then 27L in the afternoon.

27L is not always used when there are strong south westerly winds. The runway used for landing will be in accordance with the weekly alternation plan. The ATIS will warn pilots of turbulence on short final during certian wind conditions.

Just to clear up the inaccuracies.

behind_the_second_midland
5th Nov 2005, 15:04
What we are saying is that in line with the weekly rotations it should have been 27R for landings before 3pm. It was changed to 27L out of sequence due to the winds.

GT3
5th Nov 2005, 18:26
Behind the second BMI ;) I agree with you that on the day in question we did "de-alternate" due to the crosswind. However Del Prado does not seem to know what he is talking about I am afraid.

With regard to the last 200' wind, if you can when busy just give a call of "200ft wind 220/45" may be of help to the one following? However it is a very high workload situation I would expect so maybe not possible? Out of interest how helpful are our windchecks we give when you are in the final stages of approach after being given landing clearance.

BYMONEK
5th Nov 2005, 18:36
G.I.B

Double Decker bus? I didn't know the A380 was ground testing on the M4?:D

Jon Lei
5th Nov 2005, 18:47
Just wondering... at a typical flare att, what is the AoB req for an outboard engine contact on the 744's.
Thks

banana head
5th Nov 2005, 20:46
Jon Lei,
Just wondering... at a typical flare att, what is the AoB req for an outboard engine contact on the 744's.

As little as 5° to 6° angle of bank can result in a pod strike with the struts fully compressed.

JW411,
The 747 is a "kick-off drift" aeroplane (for very obvious reasons).

Not really true. I've yet to see any swept wing aircraft that will remain wings level if you 'KICK' off the drift. Gently 'PUSHING' off the drift while applying enough into wind aileron to maintain wings level is a different thing. Even having said that, have a look at a cross-wind autoland in the aircraft sometime.... It lands wing down every time. BOTH methods work, and from experience I can tell you that wing down generally results in a less 'agricultural' landing. A firm touchdown will only rapidly compress the oleo's reducing your pod/ ground clearance....Just my 2cents worth.

28L
5th Nov 2005, 22:18
>Out of interest how helpful are our windchecks we give when you are in the final stages of approach after being given landing clearance<

GT3 - Speaking for myself, if it's right on limits I'm working so damn hard the chance of me working out the sin/cos of the crosswind component is remote!
There's always the possibility of course that the wind you give me at 100' will be outside the limit, which raises the possibility of a G/A.
A change from 200/25 to 190/23 frankly isn't worth mentioning. But an instantaneous 180/50 would be worth a shout :eek:
However, I suspect it's one of those things 100 pilots would have 100 different views on.

GT3
6th Nov 2005, 09:56
Fair enough 28L, more a case of reading off the wind display in the flightdeck, or is that inhibited below certian heights?

JW411
6th Nov 2005, 10:37
banana head:

I thank you for your explanation. Perhaps you missed the inverted commas around "kick-off drift"? It is, as you say, a combination of the two.

What I was trying to impart is that you simply cannot touch down in a 747 with 10° of wing down like you can happily do in a DC-10 which is a truly wing-down technique aeroplane.

You cannot scrape a pod in a DC-10 - you get the wingtip first!

Witraz
6th Nov 2005, 11:14
I expect to be shot down for this however -
I am a wing down for x-wind landing person. After 31 years from instructing on Piper Cubs, flying Twin Otters, Shorts 360 and Islander to over 12000 hours on Boeings B737, B747 and B777. Got into trouble a few times from trainers on the B737 and also intitially on the B747 Classic. Then came the B747-400 and hey it uses wing down in autoland. More so on the B777. So I have pretty much stuck to this and so far it has worked or I have I just been lucky?

fdr
6th Nov 2005, 11:18
JL, BH......

touchdown geometry for the B744 is shown in TBC's FCTM.
Unfortunately the values are based on rigid geometry for various cases of oleo extension/roll/pitch. Wing behavior and resultant engine pod relative movement is a result of dynamic interactions of oleo rebound, spoiler, aileron input and attitude, with both feedforward and feedback. I wrote an inhouse paper based on a (limited) FEA analysis of wing behavior and it indicated pod touch was possible outside of the margins provided by the manufacturer by up to roughly 1.5 degrees.

BTW, the certification criteria encompassed by CFR14 part 25.473 and methodologically expanded by the applicable AC's/TSO's & orders such as:

AC 25-7A Flight Test Guide for Certification of Transport Category
Airplanes

AC No. 25.723-1SHOCK ABSORPTION TESTS Date: 5/25/01

¡× 25.125 Landing
AC 25.735-1 4/10/02 2
¡× 25.301 Loads
¡× 25.303 Factor of safety
¡× 25.733 Tires

¡× 25.1501 General: Systems and equipment limitations (JAR25x1524)

¡× 21.101 Designation of applicable regulations
¡× 25.943 Negative acceleration (JAR 25x1315)

AC 25.1309-1A System Design and Analysis

TSO-C26c Aircraft Wheels and Wheel-Brake Assemblies with
Addendum I
TSO-C135 Transport Airplane Wheel and Wheel and Brake Assemblies
TSO-C62d Tires

Order 8110.4A Type Certification Process
Order 8110.8 Engineering Flight Test Guide For Transport Category Airplanes :ugh:

don't account for isolated wheel loads. To consider the consequences of that look at the Mega Death 2 deal at HK-CLK (not just the deteriorating ROD[18-20FPS @ TD, enough to exceed limit and result in deformation] but the roll instability, resulting in RHW touch and catastrophic overload of the RH MLG aft bearing mount), and some sundry other deals (EWK MD11 report, P40...).

may be worthwhile being gentle with bank...or be as perfect as 411A.

did the VS guys do good? no one here is likely to know without the DFDR/QAR data, but they don't have to be incompetent to have a bad day, just like the rest of us. The eye witness report appears to be of a good operation, which is what the rest of the world generally expects, yet purveyors of the PPrune forum appear satisfied to besmirtch at the least opportunity.



cheers ;)

Wiley
6th Nov 2005, 12:02
…why do some pilots (I see it all the time in military pilots of non UK origin) transition way out to the wing down cross contol technique? Uncomfortable for SLF . So kick it off and plant it says I! It appears this is what they did and the gods where just not with them.Works fine in a Piper Cub and maybe even an ATR 42, but in my opinion, this is definitely NOT the best technique to employ in a 200 tonne aeroplane like a 777 or an A340.

The last minute kick straight is basically turning a stable crabbed approach into a horribly unstable approach at the very worst moment – a nanosecond (or hopefully only a nanosecond) before touchdown. If you judge is absolutely right, you’re the ace of the base and the pax will think you’re wonderful.

However, the magic word is ‘if’…

If you misjudge it, particularly in a strong crosswind, you end up with, at best, a not very neat touchdown, and at worst, a potential disaster of crossed arms and legs and a very big aeroplane still airborne but with a lot of momentum heading off in God knows what direction – but usually towards the downwind side of the runway at an increasingly rapid rate because your last minute “kick it off and plant it says I!” has left the aircraft pointing downwind.

In an aeroplane as big as a 777 or an A340, you run out of runway width very, very quickly, (remembering that your seating position is a very long way away from your main gear, [on the 777, around 100 feet or 30 metres]). If things start gyrating, you might stil be not too far off the runway centreline. There's no guarantee your MLG is still on (or over) the runway.

I’m definitely in the same camp as Witraz on this point. Look at the way the 777 autopilot does it – exactly as flown it accuses ex-mil non RAF types (that’s me) of doing it.

The 777 manual says that technique shouldn’t be used in crosswinds exceeding 31 knots. Boeing recommends simply flying it on while still crabbed. The enormous momentum of the aircraft sorts it out quite nicely, although obviously most pilots help it along by instinctively kicking it straight after touchdown.

Don’t believe me? Take a look at these landings by Boeing test pilots. http://www.leathermans.net/content/view/25/39/
http://www.leathermans.net/gallery/main.php?g2_view=core.DownloadItem&g2_itemId=2693&g2_GALLERYSID=56bf1581139413549009c4bf51024a51

Under 31 knots, the wing down, crossed control technique, (as the autopilot does), and aided by the track bar on the PFD, will almost always guarantee the aeroplane will roll on smoothly and stable – and that last word, in my opinion, is the most important one in the equation in big aeroplanes.

behind_the_second_midland
6th Nov 2005, 12:22
GT3

I did pass on the turb <200' after landing.

As for wind checks, fine up to about 200' then as long as the last one is in limits no more ;)

Can't remember exactly but our wind read outs work until touchdown at least.

They are inhibited <80kts on take off.

On ths subject of x winds, I ahve always been a little confused.

Our Flying manual (757/767) states we can use either technique, or a combination of the two.

Now, don't all x-wind landings use a combination of the two in the end?

I crab in and then feed cross rudder and aileron in in the latter stages, but you will ALWAYS land cross controlled with aileron into wind, or the wing will rise even in a modest x-wind.

the difference really is at which point on the approach you cross the controls.

JW411
6th Nov 2005, 13:21
Exactly so and it is nice when the aircraft configuration allows you to do it earlier rather than later!

flyer1-11
6th Nov 2005, 15:16
After 10 years of operating the 747-400 I always found the tricky bit was after touchdown.
The upwind wing just wanted to keep flying and postive use of aileron, but carefully, was necessary .
I always used kick off drift and it worked for me.
The aircraft did use wingdown for autoland but its limit was only 15kts!

BusyB
6th Nov 2005, 15:54
Flyer 1-11,

Agree with your remarks re "kicking off drift"" but would point out that the 15kt x/w autopilot limit is in fact only for LWMO ops. A/P can land with a/c limit x/w.

JW411
6th Nov 2005, 17:50
Are you seriously suggesting that on a day when the wings are clapping hands with windshear possible on finals and 35 knots across the runway that you would leave the automatics in to deal with it all on an autoland?

If so, then I am seriously glad that I am getting close to retiring!

BusyB
6th Nov 2005, 19:11
JW411,

I'm glad too!

Captain Airclues
6th Nov 2005, 20:41
BusyB

The 747-400 that I fly has a crosswind limit of 25kts for an autoland. This is a limit on the autoland system, whether or not it is in low vis. I agree with JW411 in that I wouldn't dream of attempting an autoland with a 35kt crosswind.

Airclues

BusyB
6th Nov 2005, 21:45
Captain Airclues,

I can only assume that is an operators restriction. Both -400 and 777 in my company have an LWMO restriction (because of reduced visual ref) and the a/c restriction. Whether you use it or not is up to the individual. Having sampled it I am much happier with a 777 max x/w autoland than a -400 one although that was still satis.

banana head
7th Nov 2005, 01:42
JW411, Capt Airclues & co,
While you may well have your reservations regarding autoland capability, I can assure you it is well able to cope with 35kts across on the -400....
Having said that, I too would tend towards a man landing in such weather, but I've long thought that was just because I was old fashioned!!!
:)

Incedently Busy B, why are Cathay the only company on the planet to refer to what ICAO call LVP as LWMO? Is life not complicated enough without individual companys creating there own TLC (three letter codes... or four letter codes for that matter!!!):hmm:

and fdr.... kudos! I'm very much impressed.......

behind_the_second_midland
7th Nov 2005, 08:29
We can autotoland 757/767 up to max x-wind limits now (40 kts), providing its CAT 1.

CAT2/3 remains 15 kts xwind.

Heatseeker
7th Nov 2005, 11:32
Wiley

Thanks for posting the link to the Boeing x-wind landing video. I have been carrying that movie around on a flash drive for a while wondering how to post it. The soundtrack ain't too bad either.

As a humble flight dispatcher, and not a pilot, it looks like that on Boeing a/c a wings level approach then kick it straight is the way to go.

I remember a conversation many years ago with one of our drivers about cross wind landings and I'm sure he said the same thing.

Whatever the correct technique is, my condolences to the drivers of this flight and I am happy that everybody was able to walk away from it.

H

bullshot
7th Nov 2005, 12:14
The aspect that I prefer about the wing down technique is that, once you have it stabilised, (well before the threshold), there is not much else to do other than make a normal landing. Naturally, it can get tricky at night when the w/v has a habit of changing rapidly during the last 150ft but you get the same problems crabbing it in as well.
One thing is for sure though - for these reasons a x/wind landing is far more difficult at night than during daylight (unless you are near the tropics but let's not go into that).
My understanding (just a pilot's working knowledge) of the Boeing autoland in x/winds is that it ignores up to 5deg of crab and then uses forward slip (i.e. wing down) to deal with the rest; but only up to 2 deg of slip max. Up to the 25kt x/wind maximum therefore there cannot be a risk of scraping.
The only problem with wing down is that you can apply more forward slip than necessary and not know it - which is where many pilots go wrong - arriving at the runway with too much wing down. You should never require more than 3 or 4 deg of slip (bank) even for max x/winds.
I would add though, that I have never flown 747's so what would I know about it? Bad luck to the crew involved though - could happen to any of us.

Cheers
BS

AirScrew
7th Nov 2005, 12:44
As a single engine pilot with modest experience, I am reading this thread with interest. I NORMALLY look to learn from the professionals on this form.

BUT. I see a lack of concensus on this one.

My takeaway so far is that x/w landings are a black art, and pilots expercise a variety of technique from crab to wing-down and all shades inbetween. This surprises me, for most other aspects of aviation have standard procedures. If this is the case then it must be due to a large extent on the "relatively" broad handling tolerance across a range of commerical aircraft.

Some more structured comments would help to diminish my view that x/w is a black-art....

:D :D

411A
7th Nov 2005, 13:15
Not necessarily a black art, AirScrew, but strong cross wind landings in swept wing jet transports do require skill, and basic knowledge of the geometry of the particular aircraft that you are flying.

For many years I operated the good 'ole B707, and the engine pods on this aircraft were a darn sight closer to the ground than the 747, yet in all those years of operating this, what could at times be a very limiting aircraft in adverse situations, never scrapped an engine pod and, oddly enough, neither did any of the First Officers that I trained/flew with did either.

I maintain that, with all the 'automatics' in more modern day designs, rather basic flying skills have been neglected to a large degree.

A very good FMS/FMC in a jet aeroplane might make the navigation/thrust management a breeze, but that same box has limitations, and pilots find out their true abilities when the chips are down, and the winds are a blowin'....:}

Some simply don't measure up to expectations.
And likely never will.

RVR800
7th Nov 2005, 13:26
http://winterson.com/2004/08/hong-kong-approach.html

Del Prado
7th Nov 2005, 14:31
Hi GT3,

I don't know about your watch but on my watch we always de-alternate when there's a strong SW'erly.
That's borne out by the fact Heathrow did de-alternate on the day in question due to the strong wind and associated turbulence from the hangers.

I felt a few posters on the thread were concluding the de-alternation was due to the pod scrape. I was trying to give the correct reason and thought I'd managed to explain that to BTSM, didn't think you needed to jump in with both feet about the runway alternation plan and alleging I don't know what I'm talking about.

Can you clarify for me that 27L was indeed the landing runway (against the weekly alternation) and the aircraft in question landed on the departure runway after 7am? (as I was out on a break when it happened.)




Ratarsedagain, re the other incident- thanks for clearing that up.

Gonzo
7th Nov 2005, 15:09
DP, check your PMs.

NWT
7th Nov 2005, 16:50
The plane in question did land on 27R at about 07.30am. Not sure what went on that day in terms of runway alternation, but for the rest of the day (at least till late afternoon) the landing runway was 27L and did not change over at 3pm for whatever reason.

GT3
8th Nov 2005, 07:32
I think the landing runway on the morning in question was against the alternation. However I felt it necessary to make it clear that it does not always mean de-alternation in strong winds. Remember the days of 23?

Jo90
10th Nov 2005, 19:53
My personal preference on the 757 was to try to push off about 2 thirds of the drift at 400ft or so. This way you were less cross controlled which made it easier to handle and anyway the wind nearly always drops off in the last couple of hudred feet so you mostly ended up with the nose pointing straight down the rwy once you'd flared.

BEagle
11th Nov 2005, 07:27
Hmm, I see that TEMPO 1316 21020G35KT is forecast for London Airport today. Shame that RW23 is no longer available.....

On the ancient Vickers Super FunBus, one's man (the flight engineer) did the throttles on the approach in response to the pilot's calls. Rather nautical, e.g. "Eng, 83% please". That meant you had both hands on the control column to wrestle with the beast in strongish (up to 28 kt) crosswinds rather than the Piper Cherokee one hand for control, one hand for throttle method used by the airlines of today. We used the wing-level 'crab' technique all the way to the flare, then yawed to align the a/c with the runway at the same rate the a/c was held off in the flare, ideally touching down gently with zero drift. Any swept wing roll-with-yaw characteristic was countered with opposite aileron/spoiler.

It took a fair bit of practice to fly the thing in strong crosswinds - an ILS on a gusty wet night was always rather a challenge!

PODKNOCKER
11th Nov 2005, 08:55
The B744 localizer antenna is located in the radome with the weather radar so the whole aircraft is downwind of the centreline in a crosswind. The only way the autopilot can align the body gear with the runway centreline is to use the sideslip, wing low method. Boeing recommend the De-Crab during flare method for manual landings to maintain the wings level throughout the approach, flare and touchdown. This works well if you don't float...in which case you have to resort to the sideslip wing low method to maintain the centreline. Hopefully, Boeing will locate the localizer antenna near the body gear on the B747-400 Advanced.

Flap62
12th Nov 2005, 12:56
In sporting x-wind I agree that a bigger problem is created by taking off the drift too early and thereby establishing a flightpath towards the down-wind side of the runway. Whilst it is entirely possible to land with full drift on I think that the best solution lies between the two. By starting to ease the drift off you establsh a momentum which, if you touch down at the right time, will assist in letting the aircraft "centre". If you do not get the timing quite right and find that the aircraft is starting to move down-wind, then if you still have a bit of drift on, then it is easier to maintain the centreline with a degree or two (certainly not more than a smidgin!) of bank.

Carnage Matey!
12th Nov 2005, 13:41
The B744 localizer antenna is located in the radome with the weather radar so the whole aircraft is downwind of the centreline in a crosswind

Are you sure? I seem to remember my manual says that the antenna is in the tail and switches to one on the gear when the gear is selected down. It specifically cautions against selecting the gear down immediately prior to localiser capture to prevent the autopilot missing the intercept due to switching between the antennas.

SMOC
12th Nov 2005, 15:46
Carnage Matey!, it's the glideslope you're talking about. :ok:

spannersatcx
12th Nov 2005, 17:56
Just to set the record straight, from the 744 MM:

VOR/LOC Antenna
A.
One dual-channel VOR/LOC antenna is used to provide rf signals to the ILS when the airplane is in the air prior to approach, and to the VOR system(SUBJECT 34-51-00).
B.
The VOR/LOC antenna is located on the vertical stabilizer tip. The left channel of the VOR/LOC antenna provides signals to the left ILS via the left VOR/LOC rf power divider. The right channel provides signals to the right and center ILS via the right VOR/LOC rf power divider and the right/center LOC rf power divider.
4.
Localizer Antenna
A.
Two dual-channel LOC antennas are used to provide localizer information to the receivers when the airplane is in approach mode.
B.
The LOC antennas are located on the forward pressure bulkhead inside the nose radome. One LOC antenna is located above and one below the weather radar antenna. The lower LOC antenna provides signals to the left and right ILS receivers. The upper LOC antenna provides signals to the center receiver. One channel of the upper antenna is not used.
5.
Glide Slope Capture Antenna
A.
Two dual-channel G/S capture antennas are used to provide glide slope information to the receivers before the nose landing gear is down and locked.
B.
The G/S capture antennas are located on the forward pressure bulkhead inside the nose radome below the weather radar antenna. The lower G/S capture antenna provides signals to the left and right ILS receivers.
The upper G/S capture antenna provides signals to the center receiver.

One channel of the upper antenna is not used.

srjumbo
12th Nov 2005, 20:26
B T S M... one of your first posts refers to 'My' First Officer. Don't you mean 'THE' First Officer or are you the owner?

Da Dog
12th Nov 2005, 20:42
sr jumbo:ooh: semantics, we could, if wanted, like the spellcheckers out there, try and be that clever:yuk: :yuk: but it does get boring:*

B T S M most of us know what your saying:ok:

Carnage Matey!
12th Nov 2005, 20:46
Sadly many new FOs are sold into positions of corporate slavery these days. Lured from their impoverished homelands by the promise of a good job in London as a cleaner or childminder, they find the reality is having to fly for a living at their masters beck and call to repay the costs. I happen to know Da Dog was bought at an auction outside Costa Coffee at LGW for £2000. His owner was ripped off I reckon.

BOAC
12th Nov 2005, 20:51
His owner was ripped off I reckon - yes, I should have held out for more, but at the time he was so dishevelled and disobedient I was actually lucky to get that, and it did seem like a really nice man I sold him to.

BEagle
13th Nov 2005, 07:27
The co-pilot is the co-pilot and serves his/her captain as the captain requires. The crew is not a cuddly communist committee; it is a team with a leader. Crew resource management, the buzzword for what was once known as crew co-ordination, ensures that the team works in a co-operative manner and that the right level of assistance is provided to the team leader to assist with decision making.

Things have moved on from the days when the 'boy' was expected merely to operate the radios and sort out the paperwork whilst 'sir' flew. Co-pilots have even been known to be allowed the occasional landing nowadays.

But there is only one captain of an aircraft, srjumbo, and he/she is supported by his/her crew.

arewenearlythereyet?
13th Nov 2005, 08:09
I'm sure it was just a slip of the tongue there Beags but surely you meant to say there's only one commander". I know of many situations where there are two 'captains' sitting up front. As for using the term 'co-pilot', how quaint. I know that my 'co-pilot' is actually a first officer and that for half the time were together, he or she is 'in-command' but under my supervision. I think that I then become the 'co-pilot'.

Personally, I much prefer the more modern terminology of 'pilot flying' and 'pilot not flying' or 'handling pilot' and 'non-handling pilot'. But don't let me take away from you the courtesy of being called "sir" when the need arises. I'm sure some of the ex-RAF types miss all that protocol that todays yoof lack an appreciation for.

Yes, we all know where the buck stops and no one is under any illusion that it is some sort of democracy on the flight deck, more like a benign dictatorship. I feel sorry for those 'captains' that are uncomfortable with anything other than a subservient 'co-pilot' though. On the modern airliner flight deck there is only one commander but at least two pilots. A captain in command and a n other pilot of any rank is second in command. As far as I'm concerned a co-pilot is just PNF or NHP.

Sorry if I've ruffled some feathers with such insubordination. What is the world coming to? :rolleyes:

BEagle
13th Nov 2005, 08:36
The prefix co- implies that the person is equally a qualified pilot. But is not the captain or, if you prefer, commander.

The PF/PNF, handling-non-landing, CM1/CM2 rubbish just fudges the issue.

'First officer' is a far more subservient term and doesn't even indicate that the person is a qualified pilot.

'Second pilot' once meant 'another pilot' - but was viewed as 'second class' pilot. Wrongly.

catchup
13th Nov 2005, 09:24
I'm not familiar with the 747, so could anyone help me here. What is the difference between a VOR/LOC and a LOC antenna?

regards

Ignition Override
14th Nov 2005, 05:45
Arewenearlythereyet...I believe you meant to say the "pound" stops here.:D

The term 'Copilot' can mean the same as 'Co-Captain', if both pilots each have 10-20 years flying multi-turbine "cross-country".

As for the assumption that a high level of piloting/handling skill means that no major mistakes are possible, this is only a comment about what can happen even to those who appear to be among the best, whether with rather limited experience or much more.

Two NASA astronaut trainees died many years ago flying a T-38 (advanced jet trainer) on an ILS approach into St. Louis International Airport (STL). As far as I know, it had an operating localizer and glideslope, but have no idea whether the localizer and glideslope or flight director(s) were operating properly, or whether a reasonable intercept altitude was provided by approach control, or a crappy "slam-dunk", which happens to all of us. Very closely-spaced parallel runways present various traps to those unfamiliar or in a hurry.

The fact that the tragedy involved two astronaut trainees should be something that we never forget-even after many years of flying much more stable transport aircraft.

A highly-experienced airline Line Check Airman (who gave final "sign-off" at end of IOE for new transport category jet Captains and FOs), with about 12,000 hours, almost scraped a wingtip near equipment beside a taxiway, at night, while he operated on a normal trip. He told me about it. He also admitted to getting a bit ahead of himself, at least once, tuning in the wrong VOR frequency.

So the very best pilots with the best situational awareness and handling skills can not make an expensive mistake? Do they always have absolutely perfect judgement in every situation?
:cool:

As for widebodies....no, not various Seattle-based Flight Attendants... this might be incidental, but you might find the website (don't know the name) about the MD-11's documented anomalies and aft cg interesting.:hmm: All mistakes on those clearly must involve inferior pilot handling and decision-making. :cool: Yeah, right.