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Topic: DL 763 Damaged After Hard Landing In CDG
Username: Gonzalo
Posted 2012-08-24 20:48:03 and read 33590 times.

N179DN performing flight DL 28 suffered substantial damage after a hard landing in CDG airport. Good think is nobody was injured ( except maybe the pilot's pride ). Weather was very good according to METAR.

Aircraft currently under inspection, the French authorities are investigating.


http://avherald.com/h?article=454ca645&opt=0

Would be nice if someone in Paris can help with a Pic or a more detailed report...

Rgds.
G.

Topic: RE: DL 763 Damaged After Hard Landing In CDG
Username: spiritair97
Posted 2012-08-24 20:58:08 and read 33521 times.

It seems that 767s do NOT like hard landings. They seem to sustain a lot of fuselage damage if you don't put it down right. How many 767s have now been substantially damaged by hard landings now? First Choice, ANA, LAB(?), and now Delta. Plus more that I don't remember.

Topic: RE: DL 763 Damaged After Hard Landing In CDG
Username: Gonzalo
Posted 2012-08-24 22:10:57 and read 33099 times.

Quoting spiritair97 (Reply 1):
It seems that 767s do NOT like hard landings. They seem to sustain a lot of fuselage damage if you don't put it down right. How many 767s have now been substantially damaged by hard landings now? First Choice, ANA, LAB(?), and now Delta. Plus more that I don't remember.

You can add to your list a RAM 763 damaged in JFK, but at least in that occasion the weather was a factor to explain why the landing was not good, there were heavy rain and a X-wind of 25 knots when the flare was executed, they touched down nose gear first and the aircraft sustained damages in the fuselage. Repairs lasted four months IIRC.

Rgds.
G.

Topic: RE: DL 763 Damaged After Hard Landing In CDG
Username: PHX787
Posted 2012-08-24 23:40:55 and read 32717 times.

Quoting Gonzalo (Reply 2):
You can add to your list a RAM 763 damaged in JFK, but at least in that occasion the weather was a factor to explain why the landing was not good, there were heavy rain and a X-wind of 25 knots when the flare was executed, they touched down nose gear first and the aircraft sustained damages in the fuselage. Repairs lasted four months IIRC.

Yeah same with the ANA flight, but either way if it's hard it's not gonna go well apparently. I'm interested to see where the damage occurred with the DL flight in comparison to the NH flight.

Topic: RE: DL 763 Damaged After Hard Landing In CDG
Username: Max Q
Posted 2012-08-25 00:59:36 and read 32440 times.

The 767 is a very nice handling aircraft.


Having said that, the geometry of the main landing gear with the front Bogie trailing in the forward position can make for a pretty unforgiving arrival if your sink rate is too high and especially if you have not taken out all the drift.


If anything, it seems to magnify the effects of a less than perfect arrival.


The 757, with a conventional trailing rear bogie is far more forgiving on touchdown (as long as you work on lowering the nosewheel gently)


I notice that Boeing has never used that design since, I doubt they will again and I think it's use on the A380 explains the frequent reports of firm landings on that type.

[Edited 2012-08-25 01:02:00]

Topic: RE: DL 763 Damaged After Hard Landing In CDG
Username: SXDFC
Posted 2012-08-25 05:55:31 and read 31577 times.

Quoting Max Q (Reply 4):
Having said that, the geometry of the main landing gear with the front Bogie trailing in the forward position

I have always been curious as to why Boeing decided to go with this design.. I am also a bit curious as to why the 707, A300 never had a main gear that was trailing in either the forward or the rear.

Topic: RE: DL 763 Damaged After Hard Landing In CDG
Username: questions
Posted 2012-08-25 07:57:05 and read 28813 times.

Apologies for the aviation 101 questions... but what are:

1A)

Quoting Max Q (Reply 4):
the front Bogie trailing

1B)

Quoting Max Q (Reply 4):
a conventional trailing rear bogie

2A)

Quoting Max Q (Reply 4):
if your sink rate

2B)

Quoting Max Q (Reply 4):
the drift

Topic: RE: DL 763 Damaged After Hard Landing In CDG
Username: FlySSC
Posted 2012-08-25 08:04:04 and read 28607 times.

Quoting Gonzalo (Thread starter):
Weather was very good according to METAR.

VERY strong winds in the region since this morning, with direction 180V270 and 25G40kt ... This could explain

Topic: RE: DL 763 Damaged After Hard Landing In CDG
Username: baldwin471
Posted 2012-08-25 08:10:21 and read 28467 times.

Quoting questions (Reply 6):
1A)

Quoting Max Q (Reply 4):
the front Bogie trailing

1B)

Quoting Max Q (Reply 4):
a conventional trailing rear bogie

Referring to the position of the main gear when down. Have a look at a picture of an A380/767 landing and you'll see that the wheels are angled forwards, as opposed to most something like the A330 which if you look at a picture of one landing you'll see the gear is angled backwards so you get a softer landing. Sink rate is the rate of descent (FPM)

Topic: RE: DL 763 Damaged After Hard Landing In CDG
Username: questions
Posted 2012-08-25 08:11:56 and read 28456 times.

Quoting baldwin471 (Reply 8):

Thanks.

Topic: RE: DL 763 Damaged After Hard Landing In CDG
Username: spiritair97
Posted 2012-08-25 09:11:38 and read 27078 times.

Quoting questions (Reply 6):
2A)

Quoting Max Q (Reply 4):if your sink rate

The sink rate is how fast you descend. If the sink rate is too high, there is more gravitational forces pulling down on the aircraft and more pressure build up, which leads to a hard landing.

Topic: RE: DL 763 Damaged After Hard Landing In CDG
Username: mcdu
Posted 2012-08-25 09:47:41 and read 26244 times.

Maybe it was the same crew I saw recently while waiting for the crew bus at European airport. The DL 767-300 made one of the largest bounces I have ever seen in a commercial airliner, followed by a huge pitch up in recovery that looked like they were going to strike the tail. Light winds and nice day where this event took place.

Reminds me of the old take on the DL slogan in the 80's: "We are learning to fly and it shows" vs "We love to fly and it shows"

Topic: RE: DL 763 Damaged After Hard Landing In CDG
Username: Gonzalo
Posted 2012-08-25 09:51:33 and read 26133 times.

Quoting Max Q (Reply 4):
If anything, it seems to magnify the effects of a less than perfect arrival.

True...I experienced myself one of this landings on a 763 in 2008, the landing was videotaped from behind by a spotter, and it looked perfectly fine on the tape, but it felt very shaky ( sidewards ) on board, and probably more in the aft section where I was seated...

Rgds.
G.

Topic: RE: DL 763 Damaged After Hard Landing In CDG
Username: DLDiamondboy
Posted 2012-08-25 11:19:33 and read 23996 times.

The 767 is a lot of airplane for a little landing gear. I cannot ever recall a grease job landing in a 767, always hard and firm with overhead bins coming open.

Topic: RE: DL 763 Damaged After Hard Landing In CDG
Username: cbphoto
Posted 2012-08-25 11:36:28 and read 23595 times.

Quoting DLDiamondboy (Reply 13):
The 767 is a lot of airplane for a little landing gear.

This I will agree with you!

Quoting DLDiamondboy (Reply 13):
I cannot ever recall a grease job landing in a 767, always hard and firm with overhead bins coming open.

This I do not however! I have had dozens of flights on a 767 and not once have any of the overhead bins opened up. Have they been hard landings, yes and I con honestly say I have even experienced a few "kind of smooth" landings on the 767. To simply say that every landing on a 767 is hard enough that the overhead bins open up, is a bit of an over-exaggeration to say the least!

Hopefully the a/c in question is not too badly damaged and will return to the air soon!

Topic: RE: DL 763 Damaged After Hard Landing In CDG
Username: PHX787
Posted 2012-08-25 11:40:42 and read 23498 times.

Quoting cbphoto (Reply 14):
This I will agree with you!

Do you guys think that Boeing should offer some sort of gear replacement, given that the 787 is the intended replacement?

Topic: RE: DL 763 Damaged After Hard Landing In CDG
Username: bobnwa
Posted 2012-08-25 11:44:52 and read 23402 times.

Quoting PHX787 (Reply 15):
Do you guys think that Boeing should offer some sort of gear replacement, given that the 787 is the intended replacement?

I don't think a 787 will be repacing that 763 since Delta has zero 787's on order.

Topic: RE: DL 763 Damaged After Hard Landing In CDG
Username: Stitch
Posted 2012-08-25 11:57:33 and read 23109 times.

Quoting bobnwa (Reply 16):
I don't think a 787 will be repacing that 763 since Delta has zero 787's on order.

They have 18 787-8s on order with Boeing. Originally placed by Northwest on 06-May-2005, they became DL aircraft once NW's Operating Certificate was merged and DL's became the sole OC.

Topic: RE: DL 763 Damaged After Hard Landing In CDG
Username: Alnicocunife
Posted 2012-08-25 12:06:02 and read 22901 times.

Quoting DLDiamondboy (Reply 13):
The 767 is a lot of airplane for a little landing gear.

What does little landing gear mean? 409-413k is what is under Delta's 767ER fleet. Quite strong for the intended purpose. The AD's to the B767 gear involve the trunnion attach fitting (trunnion attaches the gear to the wing) and the bogie beam pins (the "pin" that attaches the piston to the truck) Most likely not the problem. Landing on the mains and bouncing onto the nose does the most damage.

Quoting bobnwa (Reply 16):
I don't think a 787 will be repacing that 763 since Delta has zero 787's on order.

Delta has 20 787's on order for 2020 delivery.

Topic: RE: DL 763 Damaged After Hard Landing In CDG
Username: SLCGuy
Posted 2012-08-25 12:08:45 and read 22810 times.

Does anyone have definate info on the landing or damage? While the 767 is known for firm touchdown on the mains most instances of damage have been the result of rapid derotation onto the nose gear or nose gear first landings. If this was the result of a hard landing on the main gear only it must have have been one screwed up landing!

I'm betting we'll see the usual fuselage wrinkle forward of the wing consistant with hard nosegear touchdwn when photos become avaialable.

[Edited 2012-08-25 12:33:47]

Topic: RE: DL 763 Damaged After Hard Landing In CDG
Username: cargolex
Posted 2012-08-25 12:21:37 and read 22536 times.

Quoting PHX787 (Reply 15):
Do you guys think that Boeing should offer some sort of gear replacement, given that the 787 is the intended replacement?

There's no point in redesigning the landing gear after 30 years in revenue service. Yeah, we've seen a few incidents of hard landings with more than normal damage, but how many totally ordinary landings have there been in that time, millions?

Quoting bobnwa (Reply 16):

I don't think a 787 will be repacing that 763 since Delta has zero 787's on order.

Actually, they do have 18 of them on order - inherited from Northwest, but they've pushed delivery back for a very long time (2021?).

Topic: RE: DL 763 Damaged After Hard Landing In CDG
Username: CRFLY
Posted 2012-08-25 12:43:10 and read 22008 times.

What is the 767 nickname at Delta? The "Dump Truck?" Someone at Delta can confirm that?

I recall several hard landings on 767-300, especially flying on LAN! Whoop Whoop bouncing all around... No hard landings on 767-200 or 767-400 however...

Topic: RE: DL 763 Damaged After Hard Landing In CDG
Username: NWAROOSTER
Posted 2012-08-25 12:47:24 and read 21916 times.

Quoting Stitch (Reply 17):

Quoting bobnwa (Reply 16):
I don't think a 787 will be repacing that 763 since Delta has zero 787's on order.

They have 18 787-8s on order with Boeing. Originally placed by Northwest on 06-May-2005, they became DL aircraft once NW's Operating Certificate was merged and DL's became the sole OC.
Quoting Alnicocunife (Reply 18):
Delta has 20 787's on order for 2020 delivery.

Delta did pick up Northwest's commitment for 787s. However, Delta deferred their delivery until the next decade.
I think Delta will swap out the 787s for more 777s or 737-900s unless Delta really finds a need for them after all the bugs are worked out of them.   

Topic: RE: DL 763 Damaged After Hard Landing In CDG
Username: Deltal1011man
Posted 2012-08-25 12:58:43 and read 21587 times.

Quoting bobnwa (Reply 16):

How many times are you going to say that and be told they have 18 on order with 50 options?

Quoting mcdu (Reply 11):

If its so easy....feel free to go do it.      

Quoting cargolex (Reply 20):

Actually, they do have 18 of them on order - inherited from Northwest, but they've pushed delivery back for a very long time (2021?).

2020

Quoting NWAROOSTER (Reply 22):
I think Delta will swap out the 787s for more 777s or 737-900s unless Delta really finds a need for them after all the bugs are worked out of them.

so the worlds largest 763 fleet is going to be replaced with 777s and 739s?  
787s have to happen.....Or Delta will stop flying to Europe. (and South America and some Asia)

Topic: RE: DL 763 Damaged After Hard Landing In CDG
Username: UnitedTristar
Posted 2012-08-25 13:00:28 and read 21538 times.

Quoting Max Q (Reply 4):
The 757, with a conventional trailing rear bogie is far more forgiving on touchdown (as long as you work on lowering the nosewheel gently)

true dat!

I had too many nice landings in training when just kinda shoved the nose over kinda firm   

but, that was the simulator, good to practice on!

*rest assured the hydraulics on the NATCO sim's worked   

-m

  

Topic: RE: DL 763 Damaged After Hard Landing In CDG
Username: YYZAMS
Posted 2012-08-25 14:01:49 and read 21238 times.

It looks like DL 29 (the return flight) is on time. Did they have an extra plane or did they fly it back?

Topic: RE: DL 763 Damaged After Hard Landing In CDG
Username: mcdu
Posted 2012-08-25 14:02:45 and read 21694 times.

Quoting Deltal1011man (Reply 23):
If its so easy....feel free to go do it.

Actually I have. Spent many years flying the 767-300. Never bounced one or had an issue where they couldn't reuse the airplane afterwards.

I did see with my own two eyes a DL 767-300 bounce like a ball just a few weeks ago. I was giving them the benefit that it might be the same pilot. Perhaps I should reconsider that it is all of them at DL.. 

I bet the tower didn't provide them a wind check (tic)

Topic: RE: DL 763 Damaged After Hard Landing In CDG
Username: B757forever
Posted 2012-08-25 14:29:56 and read 21530 times.

Quoting NWAROOSTER (Reply 22):
I think Delta will swap out the 787s for more 777s or 737-900s unless Delta really finds a need for them after all the bugs are worked out of them


The DL business plan calls for operating an aircraft for as close to 30 years as possible (or practical) to get the maximum utilization out of the asset. DL will take the 787 around 2020 as the first 767-300ER aircraft approach that 30 year mark. There is no need in the DL fleet for additional wide body aircraft at this time.

Topic: RE: DL 763 Damaged After Hard Landing In CDG
Username: DLDiamondboy
Posted 2012-08-25 15:12:26 and read 20458 times.

Quoting cbphoto (Reply 14):
his I do not however! I have had dozens of flights on a 767 and not once have any of the overhead bins opened up.

Sorry for the confusion. Did not mean to indicate that every single flight that I have had on a 767 has had the bins come open on landing. I can specifically recall three flights were this happened:

- ATL-PHX
-ATL=SLC
-ATL-LGA

I mainly fly on 757's, MD-88 and now MD-90's as DL has started a lot of MD-90 routes out of ATL. Landing on the three aforementioned aircraft are always smoother than my experience in the 767.

Topic: RE: DL 763 Damaged After Hard Landing In CDG
Username: nwa757boy
Posted 2012-08-25 17:23:29 and read 18112 times.

Quoting CRFLY (Reply 21):
What is the 767 nickname at Delta? The "Dump Truck?" Someone at Delta can confirm that?

Some of us say it lands like a sack of potatoes being thrown down.

Topic: RE: DL 763 Damaged After Hard Landing In CDG
Username: GreenArc
Posted 2012-08-25 17:43:44 and read 17810 times.

Check the OP link for input from actual passengers.

So the latest is that it wasn't a hard landing after all. Sounds like some sort of landing gear damage after touchdown. Oh well, it was fun reading all the speculation about gear geometry and the 763 being hard to land and prone to this and that.

GreenArc

[Edited 2012-08-25 17:44:54]

Topic: RE: DL 763 Damaged After Hard Landing In CDG
Username: Gonzalo
Posted 2012-08-25 17:47:52 and read 17833 times.

Update ( from AVherald too, this wasn't in the first report I linked yesterday , it is a quote from a passenger's statement ) :

"The captain announced they needed to be inspected as part of the standard operating procedures before proceeding to the gate, his instruments revealed no anomaly with the aircraft".

This part caught my attention : "Even after the aircraft had stopped there was mild shaking of the aircraft. After a number of fire trucks had arrived and about 10-15 firemen had swarmed out to inspect the aircraft, the aircraft taxied slowly to the gate, the shaking from side to side intensified during taxi, the trucks were following the aircraft to the gate. It was too dark to see any details/damage out there".

What can be the cause of the shaking side to side during taxi ?? Blown tyres ??

Rgds.

G.

Topic: RE: DL 763 Damaged After Hard Landing In CDG
Username: spiritair97
Posted 2012-08-25 17:50:57 and read 17726 times.

Quoting Deltal1011man (Reply 23):
Quoting bobnwa (Reply 16):

Has anybody ever thought that DL might just replace the 763s with new 763s?! Everybody seems to think that any airline with 763s will replace them with 788s! Boeing created it for the airlines that will replace them with 788s. Not so that every airline will replace them with 788s.

Quoting DLDiamondboy (Reply 28):

Were all of those do,estic 763s? Could there be a difference between the domestic and intl ones? Also, the LGA landing was probably a pilot who really wanted to make sure the plane stopped in time on LGA's short runway.

Topic: RE: DL 763 Damaged After Hard Landing In CDG
Username: Gonzalo
Posted 2012-08-25 18:07:02 and read 17583 times.

Quoting GreenArc (Reply 30):
Oh well, it was fun reading all the speculation about gear geometry and the 763 being hard to land and prone to this and that.

By the way, for those who likes to see 763 landings and missed the thread with this videos a weeks ago, here is a link with several 763 landing ( the first 5 minutes, only Airbus after that ). You can even see different landing techniques in this video ( different trim at least ), and dfferent results.

http://www.youtube.com/watch?v=uvbZe87zQ4g


Rgds.
G.

Topic: RE: DL 763 Damaged After Hard Landing In CDG
Username: B757forever
Posted 2012-08-25 18:08:41 and read 17500 times.

Quoting spiritair97 (Reply 32):
Has anybody ever thought that DL might just replace the 763s with new 763s?!

No.  

Topic: RE: DL 763 Damaged After Hard Landing In CDG
Username: EK413
Posted 2012-08-25 18:09:36 and read 17696 times.

Quoting baldwin471 (Reply 8):
Quoting questions (Reply 6):
1A)

Quoting Max Q (Reply 4):
the front Bogie trailing

1B)

Quoting Max Q (Reply 4):
a conventional trailing rear bogie

Referring to the position of the main gear when down. Have a look at a picture of an A380/767 landing and you'll see that the wheels are angled forwards, as opposed to most something like the A330 which if you look at a picture of one landing you'll see the gear is angled backwards so you get a softer landing. Sink rate is the rate of descent (FPM)
Quoting questions (Reply 9):
Quoting baldwin471 (Reply 8):

Thanks.

Great username by the way 

View Large View Medium
Click here for bigger photo!

Photo © Morris Biondi


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Photo © Johannes Ossenberg


View Large View Medium
Click here for bigger photo!

Photo © Jan Ostrowski


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Photo © Dan Miclea



Sorry couldn't help my self so I have thrown in the LOT B767...

EK413

Topic: RE: DL 763 Damaged After Hard Landing In CDG
Username: audidudi
Posted 2012-08-25 18:57:03 and read 16694 times.

Quoting YYZAMS (Reply 25):

The return flight was cancelled.

http://flightaware.com/live/flight/N...N/history/20120824/1410Z/LFPG/KATL

Topic: RE: DL 763 Damaged After Hard Landing In CDG
Username: Deltal1011man
Posted 2012-08-25 19:27:05 and read 16123 times.

Quoting spiritair97 (Reply 32):

Has anybody ever thought that DL might just replace the 763s with new 763s?! Everybody seems to think that any airline with 763s will replace them with 788s! Boeing created it for the airlines that will replace them with 788s. Not so that every airline will replace them with 788s.

I'm sure someone has thought it......but logical thought? nope.

and I would be kind of surprised if Boeing is still selling PAX 767s ( i know the tanker should still be going) in 2020 anyways.

Topic: RE: DL 763 Damaged After Hard Landing In CDG
Username: ElGrandeB777CA
Posted 2012-08-25 19:36:34 and read 16128 times.

Delta has written off a bunch of airplanes over the years for hard landings. I remember a 757 in KFLL 20 years ago that sat for months before Boeing Test pilots flew it out. It needed new engine pylons, flap/slat tracks, and a gear replacement before it was flown out. Atleast a hard landing event a year from my records...but I'm in KATL, so I hear Delta news all the time...Who knows if all airlines have the same problem?

Topic: RE: DL 763 Damaged After Hard Landing In CDG
Username: SXDFC
Posted 2012-08-25 19:44:07 and read 15841 times.

Quoting spiritair97 (Reply 32):
Has anybody ever thought that DL might just replace the 763s with new 763s?!

Why replace an aircraft in which its possible replacement(s) is only a few years from delivery?

Quoting spiritair97 (Reply 32):
Were all of those do,estic 763s? Could there be a difference between the domestic and intl ones?


There is.. The domestic are not fitted with winglets, however have AVOD, the international birds ( most if not all? ) have winglets, and coming soon new seats, and the "signature" interior.

Topic: RE: DL 763 Damaged After Hard Landing In CDG
Username: DL_Mech
Posted 2012-08-25 19:53:01 and read 15790 times.

Quoting ElGrandeB777CA (Reply 38):
I remember a 757 in KFLL 20 years ago that sat for months before Boeing Test pilots flew it out. It needed new engine pylons, flap/slat tracks, and a gear replacement before it was flown out.

N678DL was repaired at FLL and is still flying today.

Topic: RE: DL 763 Damaged After Hard Landing In CDG
Username: flyhossd
Posted 2012-08-25 20:05:03 and read 15535 times.

Quoting Gonzalo (Reply 31):
What can be the cause of the shaking side to side during taxi ?

I can recall two instances that fit this description; both had the same cause - broken scissors links. In both cases, the bolt/rod between the two halves of the link had snapped, so the wheels could be pulled sideways a bit and that caused the shaking.

In both cases, I was a passenger, but had a chance to view the broken parts and watch the repair.

Is that the case here? Who knows, it's just what came to my mind.

Topic: RE: DL 763 Damaged After Hard Landing In CDG
Username: maxpower1954
Posted 2012-08-25 20:14:44 and read 15395 times.

Quoting ElGrandeB777CA (Reply 38):
Delta has written off a bunch of airplanes over the years for hard landings. I remember a 757 in KFLL 20 years ago that sat for months before Boeing Test pilots flew it out. It needed new engine pylons, flap/slat tracks, and a gear replacement before it was flown out. Atleast a hard landing event a year from my records...but I'm in KATL, so I hear Delta news all the time...Who knows if all airlines have the same problem?

I'm curious - what are some of the other Delta hard landing write offs? I know about the MD-88 at LGA in the 1990s.

Topic: RE: DL 763 Damaged After Hard Landing In CDG
Username: spiritair97
Posted 2012-08-25 20:38:15 and read 15001 times.

Quoting SXDFC (Reply 39):

Thanks for that info, but I meant is there a difference with the landing gear and overall structure of the domestics, seeing as all the flights that were listed that had had overhead bins pop open from hard landings were all domestics.

Topic: RE: DL 763 Damaged After Hard Landing In CDG
Username: Max Q
Posted 2012-08-25 21:19:31 and read 14668 times.

Quoting ElGrandeB777CA (Reply 38):
Delta has written off a bunch of airplanes over the years for hard landings. I remember a 757 in KFLL 20 years ago that sat for months before Boeing Test pilots flew it out. It needed new engine pylons, flap/slat tracks, and a gear replacement before it was flown out. Atleast a hard landing event a year from my records...but I'm in KATL, so I hear Delta news all the time...Who knows if all airlines have the same problem?

No, they don't.


Maybe it's all those ex Navy pilots Delta hired for such a long time...

Topic: RE: DL 763 Damaged After Hard Landing In CDG
Username: kaitak
Posted 2012-08-25 21:56:21 and read 14512 times.

Just a quick question: what happens to crews in situations like this? Is it a career limiting event; is the "career damage", if any, linked to the ability to repair the aircraft?

The photos kindly provided by EK413 are a perfect example of the difference between the two MLG types; you can see, on the AC 767, how the front pair of wheels will touch down first, effectively pulling the rear pair down, while on the A330 - somewhat like a ballerina "en pointe" - the rear (trailing?) wheel pair can be held up a lot more easily, and contributes (generally) to a smoother arrival.

You can see this very clearly in the excellent YT video above, from ZRH, the slo-mo showing very well how - even with relatively smooth arrivals, the rear pair of wheels in 763 landings is brought down almost immediately, while even in what seem like fairly firm arrivals, the trailing pair of wheels in A330/340 landings provide extremely effective shock absorbtion, contributing to a smoother feeling landing inside the cabin. Indeed, I recall Airbus saying, in the earlier days of A340 ops, that it didn't want pax saying that the A340 (specifically - don't know why this didn't also apply to 330s) produced hard landings.

[Edited 2012-08-25 22:08:16]

Topic: RE: DL 763 Damaged After Hard Landing In CDG
Username: Max Q
Posted 2012-08-25 22:50:52 and read 14382 times.

Quoting kaitak (Reply 45):
Just a quick question: what happens to crews in situations like this? Is it a career limiting event; is the "career damage", if any, linked to the ability to repair the aircraft?

Doubtful, but I don't really know how it works at DAL.


As long as you don't hurt anyone you can generally bend an Aircraft and just have to through more training to return to the line.


At least thats how it is at my Airline !

Topic: RE: DL 763 Damaged After Hard Landing In CDG
Username: XFSUgimpLB41X
Posted 2012-08-25 23:20:26 and read 14241 times.

Quoting ElGrandeB777CA (Reply 38):
Delta has written off a bunch of airplanes over the years for hard landings. I remember a 757 in KFLL 20 years ago that sat for months before Boeing Test pilots flew it out. It needed new engine pylons, flap/slat tracks, and a gear replacement before it was flown out. Atleast a hard landing event a year from my records...but I'm in KATL, so I hear Delta news all the time...Who knows if all airlines have the same problem?

Care to give specifics on the aircraft that were written off due to hard landings?

I'm having a hard time coming up with any...

That 757 wasn't written off, per your statement. I've flown it. There are typically a couple tail strike events a year... it is a large airline and it happens at all of them. Off the top of my head, I can think of a 737-800 and an A320 (pre merger when it was still NW) that had significant damage on landings. That's about it.

As far as a "hard landing" like this, it is a quite rare event at DL ...and at all carriers.

Topic: RE: DL 763 Damaged After Hard Landing In CDG
Username: Aesma
Posted 2012-08-25 23:53:33 and read 14337 times.

According to a comment on avherald :

N179DN suffered a nose landing gear steering compass axle failure.

The plane is in AFR's hangars since friday, on jacks, and the nose gear shock absorber is going to be changed.

Topic: RE: DL 763 Damaged After Hard Landing In CDG
Username: PHX787
Posted 2012-08-26 00:11:35 and read 14104 times.

I saw on AvHerald that it's going to be ferried back to ATL sometime soon?

Topic: RE: DL 763 Damaged After Hard Landing In CDG
Username: B757forever
Posted 2012-08-26 07:31:03 and read 13230 times.

Quoting ElGrandeB777CA (Reply 38):
Delta has written off a bunch of airplanes over the years for hard landings.

Can you provide any specifics? The 757 you mentioned was repaired and is still flying. The MD88 in LGA that someone else mentioned was repaired and is still flying today. In the last 24 years, DL has not written off one airframe for a hard landing . The only write off in the last 24 years was a 727 in SLC that had a fire at the gate.

[Edited 2012-08-26 08:12:50]

Topic: RE: DL 763 Damaged After Hard Landing In CDG
Username: audidudi
Posted 2012-08-27 08:21:12 and read 11574 times.

The aircraft is now being ferried back to ATL from CDG..

http://flightaware.com/live/flight/N179DN

Topic: RE: DL 763 Damaged After Hard Landing In CDG
Username: Md88Captain
Posted 2012-08-27 09:37:00 and read 11264 times.

Hard landings happen. The 767-300 is a nice landing airplane. The "Dump Truck" name belonged to the 767-200 which DAL did not land or fly anywhere as smoothly as the -300 and 757. The key to landing the 767-300 was keeping some power on as opposed to the 757. I don't remember any terrible landings in the 767 as compared to the MD11 which was always a handful.

Firm landings happen to all professional pilots from time to time. Sometimes they surprise us other times we do them on purpose to get an aircraft stopped. Hard landings which damage aircraft often are the result of bad technique like continuing to hold the aircraft off while trying to grease on a landing or continuing to pull the nose up trying to grease on on.

I have no idea what caused this hard landing. I have not even heard a fourth hand rumor, but I know the incident will be investigated, lessons will be learned, the crew will get a little retraining and the world will continue to spin.

Topic: RE: DL 763 Damaged After Hard Landing In CDG
Username: MountainFlyer
Posted 2012-08-27 10:31:01 and read 10857 times.

Quoting spiritair97 (Reply 10):
If the sink rate is too high, there is more gravitational forces pulling down on the aircraft and more pressure build up, which leads to a hard landing.

Not to be super picky, but the gravitational force never changes. Only lift changes as a result of changes made on the aircraft with speed and/or angle of attack. Less lift equals a higher sink rate as it allows gravity to accelerate the aircraft towards the ground more. A higher sink rate simply means the plane is descending faster than normal, and the result of touching down in this state is the difference between setting a glass on a table versus dropping it on the table.

Quoting baldwin471 (Reply 8):
Have a look at a picture of an A380/767 landing and you'll see that the wheels are angled forwards, as opposed to most something like the A330 which if you look at a picture of one landing you'll see the gear is angled backwards so you get a softer landing.

Could someone explain why a forward tilted bogie results in harder landings vs. a rear tilted bogie?

Topic: RE: DL 763 Damaged After Hard Landing In CDG
Username: FlyASAGuy2005
Posted 2012-08-27 10:35:44 and read 10849 times.

Quoting SXDFC (Reply 5):
I have always been curious as to why Boeing decided to go with this design.. I am also a bit curious as to why the 707, A300 never had a main gear that was trailing in either the forward or the rear.

Has everything to do with the landing gear bay. It hangs the way it does for gear stowage when it retracts.

Quoting B757forever (Reply 50):

Exactly!! Everyone was saying they were going to right off the 73W that vacated the taxiway/runway some time back due to the damage it sustained yet it was back in the air not too long after. She was on jacks in the TOC within days getting repaired! Even the EV CR9 that sustained heavy damage in BOS was repaired and returned to service. Word was that the frame itself received extensive damage and it would be a write-off but wasn't.

Topic: RE: DL 763 Damaged After Hard Landing In CDG
Username: MountainFlyer
Posted 2012-08-27 10:37:04 and read 10827 times.

Quoting FlyASAGuy2005 (Reply 54):

Has everything to do with the landing gear bay. It hangs the way it does for gear stowage when it retracts.

Does it? I was under the impression the gear tilted back to a neutral position on most airliners when they retracted.

Topic: RE: DL 763 Damaged After Hard Landing In CDG
Username: FlyASAGuy2005
Posted 2012-08-27 11:46:23 and read 10539 times.

Quoting MountainFlyer (Reply 55):
Does it? I was under the impression the gear tilted back to a neutral position on most airliners when they retracted.

Nope. The way it "hangs" is directly related to how it's stowed in the bay. This comes up about as much as when NW (now DL) is going to retire the DC-9s.

Topic: RE: DL 763 Damaged After Hard Landing In CDG
Username: questions
Posted 2012-08-27 12:07:18 and read 10458 times.

Quoting FlyASAGuy2005 (Reply 56):
Nope. The way it "hangs" is directly related to how it's stowed in the bay. This comes up about as much as when NW (now DL) is going to retire the DC-9s.

Or why some hang to the left.  

Topic: RE: DL 763 Damaged After Hard Landing In CDG
Username: GreenArc
Posted 2012-08-27 12:11:39 and read 10376 times.

Quoting FlyASAGuy2005 (Reply 56):

Quoting MountainFlyer (Reply 55):
Does it? I was under the impression the gear tilted back to a neutral position on most airliners when they retracted.

Nope. The way it "hangs" is directly related to how it's stowed in the bay. This comes up about as much as when NW (now DL) is going to retire the DC-9s.


The mains on the 767 retract slightly forward. When retracted, the bogies are parallel to the keel beam. When extended, they are nose down. This architecture maximizes the available cargo volume in the aft pits.

The 777 has a similar geometry, but the gear is powered nose down just prior to retraction and tail down during extension.

Nose down bogies do not produce harder landings. If you compare the 767 and 330 landings in the video, you can see that there is much greater damping in the bogie on the A330; some of the initial touchdowns were firm, but the bogie did not rotate down. Maybe just smarter, newer design.

The nose down gear does seem to make the 767 more sensitive to side loads, like landing in a crab. This seems somewhat plausible based on the geometry.

GreenArc

Topic: RE: DL 763 Damaged After Hard Landing In CDG
Username: 71Zulu
Posted 2012-08-27 12:14:04 and read 10357 times.

Do we really know that it was a hard landing?

Avherald seems to have removed any reference to that.

It could just a mechanical failure on landing right?

http://avherald.com/h?article=454ca645&opt=0

Topic: RE: DL 763 Damaged After Hard Landing In CDG
Username: kaitak
Posted 2012-08-27 12:28:34 and read 10270 times.

Quoting MountainFlyer (Reply 53):
Could someone explain why a forward tilted bogie results in harder landings vs. a rear tilted bogie?

Yes; have a look the video in Reply 33, which - very helpfully - is in slow-motion. If you look at the 767s, the impact of the forward tilted landing gear brings the rear pair down almost immediately. Now, that's quite a heavy mechanism, coming down fast, so it's hardly surprising that it's heard and felt in the cabin; conversely, look at almost all the A330/340 videos (and ironically, these were deleted from the main programme this guy was making, because they weren't smooth enough) and you can see that even in fairly firm arrivals, the A330/340 trailing pair keeps the forward pair up for quite some time; you don't get the "pulling down" effect you get on the 767.

Of course, another factor here could be particularly effective shock absorbtion on the A330/340 landing gear.

Topic: RE: DL 763 Damaged After Hard Landing In CDG
Username: MountainFlyer
Posted 2012-08-27 12:49:00 and read 10126 times.

Quoting FlyASAGuy2005 (Reply 56):
Nope. The way it "hangs" is directly related to how it's stowed in the bay. This comes up about as much as when NW (now DL) is going to retire the DC-9s.

I see that after looking at a bunch of pictures (I have no technical knowledge of 767's). I guess I haven't seen it come up in a thread before.

Quoting kaitak (Reply 60):
Yes; have a look the video in Reply 33, which - very helpfully - is in slow-motion. If you look at the 767s, the impact of the forward tilted landing gear brings the rear pair down almost immediately. Now, that's quite a heavy mechanism, coming down fast, so it's hardly surprising that it's heard and felt in the cabin; conversely, look at almost all the A330/340 videos (and ironically, these were deleted from the main programme this guy was making, because they weren't smooth enough) and you can see that even in fairly firm arrivals, the A330/340 trailing pair keeps the forward pair up for quite some time; you don't get the "pulling down" effect you get on the 767.

Of course, another factor here could be particularly effective shock absorbtion on the A330/340 landing gear.

Thanks. I guess that makes sense. Just purely speculation, but I would hazard a guess that it might have more to do with newer/better design than the orientation of it, like was said by GreenArc. I may be missing something, but I see no real reason why the nature of the orientation alone would cause the harder landings.

Quoting GreenArc (Reply 58):
Nose down bogies do not produce harder landings. If you compare the 767 and 330 landings in the video, you can see that there is much greater damping in the bogie on the A330; some of the initial touchdowns were firm, but the bogie did not rotate down. Maybe just smarter, newer design.

That makes more sense to me.

Topic: RE: DL 763 Damaged After Hard Landing In CDG
Username: B757forever
Posted 2012-08-27 12:49:37 and read 10219 times.

Quoting 71Zulu (Reply 59):
Do we really know that it was a hard landing?



It apparently was not due to a hard landing. There was a failure of some part of the NLG. I have no details though. 

Topic: RE: DL 763 Damaged After Hard Landing In CDG
Username: Max Q
Posted 2012-08-27 14:22:47 and read 9765 times.

Have to disagree with keeping power on for a smoother landing.


Unless you have a last minute high sink rate close to the runway requiring extra thrust you will always get a smoother landing with the power at idle.


Leaving power on actually just drives the Aircraft into the ground harder.


That's true on any Aircraft from a Cessna 150 to a B747.

Topic: RE: DL 763 Damaged After Hard Landing In CDG
Username: XFSUgimpLB41X
Posted 2012-08-27 15:16:19 and read 9594 times.

Quoting Max Q (Reply 63):

Have to disagree with keeping power on for a smoother landing.


Unless you have a last minute high sink rate close to the runway requiring extra thrust you will always get a smoother landing with the power at idle.


Leaving power on actually just drives the Aircraft into the ground harder.


That's true on any Aircraft from a Cessna 150 to a B747.

The 767ER lands best with closing the throttles as you enter the flare. The domestic 767s with the non fadec engines are a whole different story. Flare with the power in and pull the power when you want it to touch down...if you're 20 feet or 1 foot off the ground, that thing is coming out of the sky wherever you pull the throttles out!

Topic: RE: DL 763 Damaged After Hard Landing In CDG
Username: Gonzalo
Posted 2012-08-27 15:38:56 and read 9405 times.

Quoting 71Zulu (Reply 59):
Do we really know that it was a hard landing?

Apparently yes :

Quoting Aesma (Reply 48):
N179DN suffered a nose landing gear steering compass axle failure.

The plane is in AFR's hangars since friday, on jacks, and the nose gear shock absorber is going to be changed.
Quoting audidudi (Reply 51):
The aircraft is now being ferried back to ATL from CDG..

http://flightaware.com/live/flight/N179DN

You don't do anything of this if you have a normal landing. Maybe the definition of "hard" is the problem here....

Rgds.
G.

Topic: RE: DL 763 Damaged After Hard Landing In CDG
Username: XFSUgimpLB41X
Posted 2012-08-27 15:52:01 and read 9331 times.

Quoting Gonzalo (Reply 65):
You don't do anything of this if you have a normal landing. Maybe the definition of "hard" is the problem here....

Rgds.
G.

There was obviously no worry of pressure hull damage considering they were up at FL400.

Topic: RE: DL 763 Damaged After Hard Landing In CDG
Username: Max Q
Posted 2012-08-27 16:07:34 and read 9252 times.

Quoting XFSUgimpLB41X (Reply 64):

The 767ER lands best with closing the throttles as you enter the flare. The domestic 767s with the non fadec engines are a whole different story. Flare with the power in and pull the power when you want it to touch down...if you're 20 feet or 1 foot off the ground, that thing is coming out of the sky wherever you pull the throttles out!

Agree completely.

Topic: RE: DL 763 Damaged After Hard Landing In CDG
Username: FlyASAGuy2005
Posted 2012-08-27 17:06:26 and read 9104 times.

Quoting Gonzalo (Reply 65):
You don't do anything of this if you have a normal landing. Maybe the definition of "hard" is the problem here....

Rgds.
G.

Things do break occasionally. It it doesn't have to have ANYTHING to do with the landing. See

Quoting B757forever (Reply 62):
It apparently was not due to a hard landing. There was a failure of some part of the NLG. I have no details though.

Much more knowledgeable than most of us on this particular matter as he's "boots on ground" so to speak.

Was once on a CR2 that had to return to the gate due to one of the gear struts failing. After much conversation with the EV mechanics, it simply turned out to be the case of wear and tear and the thing gave way at the worst time.

Topic: RE: DL 763 Damaged After Hard Landing In CDG
Username: Md88Captain
Posted 2012-08-27 17:37:29 and read 9027 times.

Max Q. You must have never flown the 727. It didn't know that all planes land power off.

[Edited 2012-08-27 17:40:39]

Topic: RE: DL 763 Damaged After Hard Landing In CDG
Username: stasisLAX
Posted 2012-08-27 20:40:12 and read 8616 times.

Quoting B757forever (Reply 62):
It apparently was not due to a hard landing. There was a failure of some part of the NLG. I have no details though.

The failed part in the nose landing gear was apparently the " lower torque link pin broke causing the lower torque linkage to partially detach from the nose gear wheel axle section" thus leading to the excessive vibration and shaking at any taxi speed. Not the fault of the flight crew (ie - not a hand landing) at all according to the Aviation Herald.

Topic: RE: DL 763 Damaged After Hard Landing In CDG
Username: audidudi
Posted 2012-08-27 21:37:57 and read 8447 times.

I was wondering how often this has happened before on a 767? Was this just a freak occurrence or something that could/should have been caught before it happened?

Topic: RE: DL 763 Damaged After Hard Landing In CDG
Username: FlyASAGuy2005
Posted 2012-08-27 21:53:12 and read 8424 times.

Quoting audidudi (Reply 71):
I was wondering how often this has happened before on a 767? Was this just a freak occurrence or something that could/should have been caught before it happened?

I can tell you that when I use to work the ramp (this was RJs though) special attention had to be given to the CRJ scissor link for this very reason. There was a rash torque link failures around 2005-2006 on the CR2s. It was proven that the training programs were not specifically mentioning the fact that the "scissor" is to be disconnected on pushback with the LEKTRO even if it'll be "straight back".

This is just one example but i'm sure there can be a host of reasons as to why it failed.

BTW, check your PM

[Edited 2012-08-27 21:53:41]

Topic: RE: DL 763 Damaged After Hard Landing In CDG
Username: Max Q
Posted 2012-08-28 01:07:38 and read 8210 times.

Quoting Md88Captain (Reply 69):
s:

Max Q. You must have never flown the 727. It didn't know that all planes land power off.

I flew the 727 for seven years. I've never known an aeroplane that 'knew' anything it's up to the Pilot to control it.


Barring an unforeseen last minute sink rate I used to go to idle power in the flare and land that way in the 727 all the time. Just as was recommended in the flight manual. If you did it properly it was always more gentle than 'powering it on'


I saw more guys getting into trouble on that plane by keeping loads of power on and / or pushing over in the flare, then porpoising half way down the runway barely getting it stopped after they finally 'hit'


All this because they were afraid to fly it like an aeroplane.


Aeroplanes don't 'know' anything MD88, their Pilots on the other hand are supposed to !

Topic: RE: DL 763 Damaged After Hard Landing In CDG
Username: Dizzy777
Posted 2012-08-28 12:41:41 and read 7420 times.

Quoting FlyASAGuy2005 (Reply 54):
Has everything to do with the landing gear bay. It hangs the way it does for gear stowage when it retracts.

Sorry,but this is NOT true for the A330. the MLG leg/strut is too long to retract straight into place. the A330 MLG strut compresses during retraction and the gear returns to a level/neutral position in order to fit into is compartment.

Will go back thru my type notes to find the exact wording for you at some stage today.

pretty clear view (best i can find) here to illustrate it

http://www.youtube.com/watch?v=YRa0sjTYVx4




(edit to add video link)

[Edited 2012-08-28 12:56:53]

Topic: RE: DL 763 Damaged After Hard Landing In CDG
Username: FlyASAGuy2005
Posted 2012-08-28 12:56:44 and read 7281 times.

Quoting Dizzy777 (Reply 74):
Sorry,but this is NOT true for the A330. the MLG leg/strut is too long to retract straight into place. the A330 MLG strut compresses during retraction and the gear returns to a level/neutral position in order to fit into is compartment.

Will go back thru my type notes to find the exact wording for you at some stage today.

I was actually refering to the way the '67 gear hangs..

Topic: RE: DL 763 Damaged After Hard Landing In CDG
Username: cubastar
Posted 2012-08-28 13:02:06 and read 7311 times.

Quoting Max Q (Reply 73):
Barring an unforeseen last minute sink rate I used to go to idle power in the flare and land that way in the 727 all the time.

On some landings it was sorta fun to pull 1 &3 to idle during the flare (as you said) and squeak it on while slowly pulling #2 back to idle.

Did you always land "power off" when landing with 40 flaps?

Topic: RE: DL 763 Damaged After Hard Landing In CDG
Username: Tristarsteve
Posted 2012-08-28 13:33:07 and read 7216 times.

Quoting FlyASAGuy2005 (Reply 54):
Has everything to do with the landing gear bay. It hangs the way it does for gear stowage when it retracts

Don't know if hang is an American slang word or not, but
gear does not hang. All gears with trucks, have the truck positioned in a particular position.
Normally there is a truck positioner, which is a hyd jack that is pressurised all the time. It positions the truck in the way we see it when the aircraft is flying. Contact with the ground overpowers this jack. If the truck is not positioned correctly after take off, the gear will not retract.
There are many variations on this, like the B777 that has two positions for the positioner, and many variations of how gears retract like the A330/A340/Concorde that shorten the gear before retracting, and the good old Trident where the main gear rotated through 90deg during retraction, and the nose gear retracted sideways!

Topic: RE: DL 763 Damaged After Hard Landing In CDG
Username: B757forever
Posted 2012-08-28 18:53:11 and read 6824 times.

Quoting audidudi (Reply 71):
I was wondering how often this has happened before on a 767? Was this just a freak occurrence or something that could/should have been caught before it happened?


I do not recall seeing this on a 767, but I am still not 100% sure of exactly which part failed. DL has an optional spring-loaded quick disconnect for the NLG scissor links on the 757 and 767, the normal configuration being a bolt, castellated nut and cotter key. The QD allows for disconnecting the link for ground handling if needed. I have seen a failure of this QD on a 757 which caused the extreme shaking and shuddering as described in this incident.

Topic: RE: DL 763 Damaged After Hard Landing In CDG
Username: FlyASAGuy2005
Posted 2012-08-28 19:04:09 and read 6789 times.

Quoting Tristarsteve (Reply 77):
Don't know if hang is an American slang word or not

Yes, just slang   I'm not saying they literally "hang" like freely hang as they please, but thanks  

Topic: RE: DL 763 Damaged After Hard Landing In CDG
Username: Max Q
Posted 2012-08-28 19:10:46 and read 6820 times.

Quoting cubastar (Reply 76):

On some landings it was sorta fun to pull 1 &3 to idle during the flare (as you said) and squeak it on while slowly pulling #2 back to idle.

Did you always land "power off" when landing with 40 flaps?

We didn't use 40 flaps (except for Air Micronesia) in fact that position was blocked off physically by a bolt.


30 flaps was normal landing flaps for us.

Topic: RE: DL 763 Damaged After Hard Landing In CDG
Username: Gonzalo
Posted 2012-08-29 04:38:26 and read 6278 times.

Quoting B757forever (Reply 78):
I have seen a failure of this QD on a 757 which caused the extreme shaking and shuddering as described in this incident.

Is the shaking and shuddering the worst possible consequence of this failure ?? I mean, could this failure lead to a runway excursion / loss of directional control if happens combined with adverse conditions ? ( i.e. combined with crosswinds / slippery runway )

Rgds.

G.

Topic: RE: DL 763 Damaged After Hard Landing In CDG
Username: B757forever
Posted 2012-08-29 13:30:09 and read 5789 times.

Quoting Gonzalo (Reply 81):
Is the shaking and shuddering the worst possible consequence of this failure ?? I mean, could this failure lead to a runway excursion / loss of directional control if happens combined with adverse conditions ? ( i.e. combined with crosswinds / slippery runway )

The 757 failure I saw happened very early in the takeoff roll causing severe shaking and shuddering to the point that PSUs and ceiling panels came down. It also broke the radar antenna off it's mount. Could it have been worse? I suppose. Not being a pilot, I am not the most qualified to answer, but from an AMTs perspective, anytime you lose the ability to steer the aircraft, it is not a good thing...

Topic: RE: DL 763 Damaged After Hard Landing In CDG
Username: burnsie28
Posted 2012-08-29 18:30:26 and read 5427 times.

Aircraft is back in service and currently on its way to FCO.

Topic: RE: DL 763 Damaged After Hard Landing In CDG
Username: burnsie28
Posted 2012-09-10 07:12:06 and read 4428 times.

Oddly enough this aircraft will be returned to the lessor 12/20

Topic: RE: DL 763 Damaged After Hard Landing In CDG
Username: Md88Captain
Posted 2012-09-10 07:33:10 and read 4431 times.

Quoting Max Q (Reply 73):

Well Max, I see very clearly that your telling me I don't know how to fly. I've wasted 15000hrs+, 10 type rides, and a previous military career. If I'd only known that I just needed to listen to you and your "aeroplane" wisdom. Woulda,. coulda, shoulda

Topic: RE: DL 763 Damaged After Hard Landing In CDG
Username: FlyASAGuy2005
Posted 2012-09-10 14:21:46 and read 4331 times.

Quoting Md88Captain (Reply 85):
Well Max, I see very clearly that your telling me I don't know how to fly. I've wasted 15000hrs+, 10 type rides, and a previous military career. If I'd only known that I just needed to listen to you and your "aeroplane" wisdom. Woulda,. coulda, shoulda

This may be a bit fussy but I thought that power off is what caused that AA 727 to crash in STT 30+ years ago?

Topic: RE: DL 763 Damaged After Hard Landing In CDG
Username: rwessel
Posted 2012-09-10 16:40:26 and read 4201 times.

Quoting kaitak (Reply 60):
Yes; have a look the video in Reply 33, which - very helpfully - is in slow-motion. If you look at the 767s, the impact of the forward tilted landing gear brings the rear pair down almost immediately. Now, that's quite a heavy mechanism, coming down fast, so it's hardly surprising that it's heard and felt in the cabin; conversely, look at almost all the A330/340 videos (and ironically, these were deleted from the main programme this guy was making, because they weren't smooth enough) and you can see that even in fairly firm arrivals, the A330/340 trailing pair keeps the forward pair up for quite some time; you don't get the "pulling down" effect you get on the 767.

The rate at which the raised wheels come down to the pavement (after the low wheels hit) is solely dependent on the rate of descent of the main strut, the struts position on the bogie, and the length of the bogie. Assuming the strut is attached approximately in the center of the bogie (it almost always is), and bogies of similar length, the rate of descent of the "other" end of the bogie would be identical for bogies with leading and trailing droops.

Topic: RE: DL 763 Damaged After Hard Landing In CDG
Username: DTWPurserBoy
Posted 2012-09-10 16:50:13 and read 4185 times.

Having worked both 767 and A330's, I can honestly say I have had harder landings on the A330. With the nose sitting lower than the tail, many pilots new to the aircraft stop flying the airplane when the horizon hits the spot on the windshield that they are used to seeing---and that nose gear will hammer into the ground the last 3 feet. The A330 has 3 distinct impacts--rear main bogeys, front mains and then the nose. But then, IMHO, Airbuses always seem to land hard. Rarely ever see a hard landing on the 74''s.

Topic: RE: DL 763 Damaged After Hard Landing In CDG
Username: HOMsAR
Posted 2012-09-10 17:00:33 and read 4123 times.

I recall reading somewhere (don't recall where, exactly) that the 767's landing gear having a front-wheels-down position was a compromise made necessary when their initial design didn't quite fit. This was back before computerized designs, so they actually had to take blueprints and build the thing to see how it all fit together.

I don't know if it was when they built the first plane, or if it was during a mock-up of that section, but at some point they discovered the gear wouldn't properly retract into the landing gear bays. They had to design some sort of mechanism to push the front part forward in order to get it to fit, otherwise they'd have to do an expensive redesign of that part of the plane.

It's probably in one of the couple dozen aviation books I have on my shelf, but wouldn't necessarily know which one.

Topic: RE: DL 763 Damaged After Hard Landing In CDG
Username: flyhossd
Posted 2012-09-10 17:51:27 and read 3999 times.

Quoting Md88Captain (Reply 69):
Max Q. You must have never flown the 727. It didn't know that all planes land power off.
Quoting Max Q (Reply 73):
Barring an unforeseen last minute sink rate I used to go to idle power in the flare and land that way in the 727 all the time. Just as was recommended in the flight manual. If you did it properly it was always more gentle than 'powering it on'
Quoting Md88Captain (Reply 85):
Well Max, I see very clearly that your telling me I don't know how to fly. I've wasted 15000hrs+, 10 type rides, and a previous military career. If I'd only known that I just needed to listen to you and your "aeroplane" wisdom. Woulda,. coulda, shoulda

FWIW, I agree with Max Q; my technique was the same as his (6 years on 727-200s).

How does the MD-80 compare to the 727 in landing technique?

(Thread drift, I know...)

Topic: RE: DL 763 Damaged After Hard Landing In CDG
Username: XFSUgimpLB41X
Posted 2012-09-10 18:36:25 and read 3865 times.

Quoting flyhossd (Reply 90):
How does the MD-80 compare to the 727 in landing technique?

Pull the power when you want it to come out of the sky... no matter high high you are, when you go to idle, it will be coming down!


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