boeing767mech
Topic Author
Posts: 805
Joined: Fri Dec 15, 2000 5:03 pm

757 Wet Tail?

Fri Sep 23, 2011 4:54 pm

So the other day I was in the stab compartment doing a stab jack screw inspection and looking at the horz. stab I was wondering if Boeing had ever designed the stab to be used as a fuel tank like the 747-400 and Airbus. Some of the inpsection plates look like they could be used to mount a boost pump and fuel quanity wire harness. Just wondering.

http://i59.photobucket.com/albums/g299/boeing767mech/100_0743.jpg

If you look at the photo you can see the panels in question.

David
Never under-estimate the predictably of stupidty
 
User avatar
Stitch
Posts: 23206
Joined: Wed Jul 06, 2005 4:26 am

RE: 757 Wet Tail?

Fri Sep 23, 2011 9:46 pm

It may have been a consideration, but it was never offered as an option.
 
Max Q
Posts: 5644
Joined: Wed May 09, 2001 12:40 pm

RE: 757 Wet Tail?

Sat Sep 24, 2011 1:00 am

I think it was considered when they proposed a longer range version of the -200 prior to shutting the line down.




If I remember correctly Boeing was suggesting using the -300 wing and higher gross weight, updated cockpit similar to the 764 and a stabiliser fuel tank (2000 gallons ?)



There may have been an engine upgrade as well.



A great shame there was a temporary lull in demand and they shut the line down.



Such a revamped version would still be selling well today.



Great Picture by the way, could you post more like that, of places in Aircraft that people rarely see ?
The best contribution to safety is a competent Pilot.
 
boeing767mech
Topic Author
Posts: 805
Joined: Fri Dec 15, 2000 5:03 pm

RE: 757 Wet Tail?

Sat Sep 24, 2011 7:14 am

Quoting Max Q (Reply 2):
Great Picture by the way, could you post more like that, of places in Aircraft that people rarely see

Thanks, nice thing about having cargo pants for the uniform is I can keep my digital camera with me. Helps when I have questions like this one.


This was a early 757 so I wonder if they didn't think about making a wet tail early on, but never got the interest from the airlines.


David

[Edited 2011-09-24 00:23:18]
Never under-estimate the predictably of stupidty
 
airport1970
Posts: 50
Joined: Sun Apr 17, 2011 6:32 am

RE: 757 Wet Tail?

Sat Sep 24, 2011 9:58 am

Heyya... please keep the inside pictures coming!
Everyone here is obviously a .nut but not everyone knows how these beasts work. It would be cool if you could snap a shot whenever and give a quick overview of what we are looking at.
 
User avatar
HAWK21M
Posts: 29867
Joined: Fri Jan 05, 2001 10:05 pm

RE: 757 Wet Tail?

Sun Sep 25, 2011 12:18 pm

Quoting Max Q (Reply 2):

A great shame there was a temporary lull in demand and they shut the line down.

True.....No one thought the demand would rise again......

Quoting airport1970 (Reply 4):
. please keep the inside pictures coming!

True these Inside pics sure are excellent.
I may not win often, but I damn well never lose!!! ;)
 
tdscanuck
Posts: 8572
Joined: Wed Jan 11, 2006 7:25 am

RE: 757 Wet Tail?

Sun Sep 25, 2011 5:37 pm

Quoting airport1970 (Reply 4):
Heyya... please keep the inside pictures coming!

Here's what I've got.

http://img38.imageshack.us/img38/442/20050519062.jpg
This is inside the top of the strut on a 737-Classic. The giant green thing is the thust link...what's interesting here is the fuse pin (pointed at by the silver placard). The fuse pin is at the top of the thrust link and is designed to break away if the strut is overloaded, rather than tearing open the wingbox. The various tubes are hydraulic, fire protection, and fuel.

http://img402.imageshack.us/img402/6953/20050519036.jpg

This is the inside of the trailing edge of a 737-Classic, somewhere between the strut and the body, with the flaps down. It shows how tightly packed this area is. The big green tube is the flap driveshaft. Behind that is the fire protection supply (big white tube) and the hydraulic supply (silver with yellow/blue tape). Behind that are smaller hydraulic tubes providing power to individual control surfaces, and behind that are assorted flight control cables.

http://img855.imageshack.us/img855/1199/20050519015.jpg

This is the inside of the back of the strut on a 737-Classic, which doubles as a flap fairing. It shows really well how big and beefy the flap tracks are (the bendy I-beam). You can see the bottom of the flap carriage near the end of the track.

http://img6.imageshack.us/img6/5647/20050513007.jpg

This is the top of the engine on a 737NG. The thrust link is the very large diagonal tube (the fan case is the just visible green edge to the extreme right). The big shiny block top-left is the bleed air precooler...bleed air comes up from the engine through the lower duct, cooling air from the fan duct comes in from the right. "Cool" bleed air exits out the top and goes up the strut.

Tom.
 
2H4
Posts: 7960
Joined: Tue Oct 19, 2004 11:11 pm

RE: 757 Wet Tail?

Sun Sep 25, 2011 6:03 pm

Quoting tdscanuck (Reply 6):
This is the inside of the back of the strut on a 737-Classic, which doubles as a flap fairing. It shows really well how big and beefy the flap tracks are (the bendy I-beam).

When damage occurs from extending the flaps overspeed, are these tracks typically what become damaged?

Quoting tdscanuck (Reply 6):
This is the top of the engine on a 737NG. The thrust link is the very large diagonal tube

Are those titanium?
Intentionally Left Blank
 
tdscanuck
Posts: 8572
Joined: Wed Jan 11, 2006 7:25 am

RE: 757 Wet Tail?

Sun Sep 25, 2011 6:56 pm

Quoting 2H4 (Reply 7):
Are those titanium?

15-5PH stainless steel.

Quoting 2H4 (Reply 7):
When damage occurs from extending the flaps overspeed, are these tracks typically what become damaged?

Out of my area of expertise...I suspect it's more likely to be the flap carriage or the carriage/flap interface than the track, but dynamicsguy is in a much better position to answer. When you're at, say, Flaps 5 the track isn't anywhere close to being loaded as heavily as it is at Flaps 30 but you can still overspeed the flaps...that makes me think it's something on the flap side rather than the track side.

Tom.
 
yeelep
Posts: 727
Joined: Mon Apr 04, 2011 7:53 pm

RE: 757 Wet Tail?

Sun Sep 25, 2011 7:16 pm

Quoting 2H4 (Reply 7):
When damage occurs from extending the flaps overspeed, are these tracks typically what become damaged?

In my experience, no.

Below is a summary of the conditional flap/slat overspeed inspection for the 737NG.

General inspection criteria:
(1) Cracks
(2) Pulled apart structure
(3) Loose paint (paint flakes)
(4) Twisted parts (distortion)
(5) Bent components
(6) Loose fasteners
(7) Fasteners holes that became larger or longer
(8) Fasteners that have pulled out or are missing
(9) Delaminations
(10) Fiber breakouts
(11) Misalignment
(12) Interference
(13) Other signs of damage.

Phase 1: Up to 15kt overspeed.
Examine the trailing edge flap and leading edge flap/slat components as follows:
(a) Examine the external skin of all flaps.
(b) Examine the flaps adjacent to the support structure for openings, distortions, or split
sealant.

Phase 2: Over 15kt overspeed.
Examine the trailing edge flap components as follows:
(a) the flap tracks
(b) the flap linkages
(c) the track attachment points
(d) the flap track support fittings
(e) the wing in-spar surfaces near flap support fittings
(f) the flap carriages for cracks
1) the bearings and the mounting bolts
(g) the actuator support structure
(h) the actuator and drive mechanism.

(4) Remove all of the trailing edge flap support-track fuse pins or bolts.
(a) Remove the fuse pin or bolt one at a time.
1) Examine the fuse pins or bolts for cracks or distortion.

Examine the leading edge flap and slat components as follows:
(a) External skins of flaps and slats
(b) Leading edge flap hinge rib and linkage attachments
(c) Slat auxiliary and main tracks
(d) Leading edge flap and slat support ribs and adjacent skin panels
(e) All drive mechanisms and related support structure
(f) Remove slat main track and auxiliary track roller bolts.
NOTE: You can insert a retaining pin to hold the roller bearing or slat while the bolt is
removed.
1) Make sure the bolts are not cracked, bent, or show other signs of damage.

Phase 2 insp. = pissed off mechanics.
 
2H4
Posts: 7960
Joined: Tue Oct 19, 2004 11:11 pm

RE: 757 Wet Tail?

Sun Sep 25, 2011 7:24 pm

Cool...very interesting perspective. Thanks, guys.
Intentionally Left Blank
 
boeing767mech
Topic Author
Posts: 805
Joined: Fri Dec 15, 2000 5:03 pm

RE: 757 Wet Tail?

Mon Sep 26, 2011 5:18 am

Not a inside picture, but this is something we found during a overweight landing inspection.

http://i59.photobucket.com/albums/g299/boeing767mech/105_0732.jpg

All I can tell you is yes this is a 757. The airplane landed at another station to drop off a sick passenger. They did a overweight landing inspection (so they say). After leaving this station on the way here the ATC called and told the crew that they had left something behind. We did a fly by here in LAX and yes saw he was missing the #3 wheel and brake assy. The NTSB is still looking into this issue. So this is all I can tell you.....

David
Never under-estimate the predictably of stupidty
 
airnorth
Posts: 173
Joined: Thu Jun 09, 2011 7:30 am

RE: 757 Wet Tail?

Mon Sep 26, 2011 5:35 am

great pics and insight!
Thanks very much!
 
ferpe
Posts: 2651
Joined: Tue Nov 30, 2010 7:44 am

RE: 757 Wet Tail?

Mon Sep 26, 2011 4:45 pm

Thanks all, great insight how it looks in real life.

Tom,

those control wire wheels and wires (guess it should be to the ailerons) look awfully open to debris, is this the flap compartment which opens once you lower the flap (guess it should be), no additional hatch or cover removed?


If so, better not having any back-draught of dirt and stones ending up there, but I guess 45 years of practical use has shown it as a no issue then?

[Edited 2011-09-26 09:49:00]
Non French in France
 
yeelep
Posts: 727
Joined: Mon Apr 04, 2011 7:53 pm

RE: 757 Wet Tail?

Mon Sep 26, 2011 6:46 pm

Quoting ferpe (Reply 13):
those control wire wheels and wires (guess it should be to the ailerons) look awfully open to debris, is this the flap compartment which opens once you lower the flap (guess it should be), no additional hatch or cover removed?

Your'e right, the pair of large cables/pulleys are are for the ailerons. The smaller cables above the aileron cables are for the #6 and #7 spoilers. The picture appears to be taken just outboard of the #5 ground spoiler outboard actuator, about one to two feet inboard of the #6 flap fairing located behind the #2 engine pylon. No additional hatch or cover, the flaps retract into the aft portion of the space.
 
tdscanuck
Posts: 8572
Joined: Wed Jan 11, 2006 7:25 am

RE: 757 Wet Tail?

Tue Sep 27, 2011 4:19 am

Quoting ferpe (Reply 13):
look awfully open to debris, is this the flap compartment which opens once you lower the flap (guess it should be), no additional hatch or cover removed?

As yeelep said, there's no additional hatch or cover. The flap itself plugs up the back side of this space when the flap is retracted, so it's only exposed when the flaps are down. This is, obviously, also when you're on the ground and there's FOD around but, as you guessed:

Quoting ferpe (Reply 13):
If so, better not having any back-draught of dirt and stones ending up there, but I guess 45 years of practical use has shown it as a no issue then?

You do see a lot of dirt in there after a while, but I've never heard of anything of substance getting jammed or otherwise causing damage. Because this area is on the trailing edge, it's pretty well sheltered from the airstream.

A much bigger horror from an exposure point of view is the 737 wheel well:
http://www.airliners.net/photo/Lauda...d=76aaf96ee85f426e555055b6fca5e11b
http://www.airliners.net/photo/Air-B...d=76aaf96ee85f426e555055b6fca5e11b
http://www.airliners.net/photo/Air-B...d=76aaf96ee85f426e555055b6fca5e11b

Virtually every system on the airplane except ECS has major components in there with the main landing gear tires mere inches away and all the crud blown up from the runway going all over the place.

Tom.
 
ferpe
Posts: 2651
Joined: Tue Nov 30, 2010 7:44 am

RE: 757 Wet Tail?

Tue Sep 27, 2011 5:07 am

That is way crowded, guess some are serviceable items but others pass there as this is the crossroads for fuselage-back forth and wing left-right behind the wingbox, Don't see any control wires though, phieeew  .
Non French in France
 
Max Q
Posts: 5644
Joined: Wed May 09, 2001 12:40 pm

RE: 757 Wet Tail?

Tue Sep 27, 2011 8:00 am

Quoting boeing767mech (Reply 11):

Thats quite something, another very interesting picture.



These photographs are so unique, interesting and educational to many of us.



How about a separate forum for them ?!
The best contribution to safety is a competent Pilot.
 
tdscanuck
Posts: 8572
Joined: Wed Jan 11, 2006 7:25 am

RE: 757 Wet Tail?

Tue Sep 27, 2011 2:06 pm

Quoting ferpe (Reply 16):
Don't see any control wires though, phieeew

Actually, there are a bunch...the aileron and spoiler mixer is on the aft wall of the wheel well. It's barely visible in this photo if you know exactly what you're looking for as a while vertical tube with cams behind the hydraulic fluid reservoir on the left:
http://www.airliners.net/photo/Air-B...d=76aaf96ee85f426e555055b6fca5e11b

You can see one pair of cables exiting away from you above/right of the landing gear mount and another pair coming towards you at the top right of the photo.

Tom.
 
tdscanuck
Posts: 8572
Joined: Wed Jan 11, 2006 7:25 am

RE: 757 Wet Tail?

Tue Sep 27, 2011 4:18 pm

Quoting tdscanuck (Reply 18):
Actually, there are a bunch...the aileron and spoiler mixer is on the aft wall of the wheel well. It's barely visible in this photo if you know exactly what you're looking for as a while vertical tube with cams behind the hydraulic fluid reservoir on the left:
http://www.airliners.net/photo/Air-B...d=76aaf96ee85f426e555055b6fca5e11b

Darn it...wrong link, wrong side. This is the correct photo:
http://www.airliners.net/photo/Air-Berlin/Boeing-737-86J/0114913/L/

And the hydraulic reservoir in question is on the right high up.

Tom.
 
LU9092
Posts: 102
Joined: Thu Oct 18, 2007 2:09 am

RE: 757 Wet Tail?

Wed Sep 28, 2011 1:37 am

Quoting tdscanuck (Reply 19):
Darn it...wrong link, wrong side. This is the correct photo:
http://www.airliners.net/photo/Air-Berlin/Boeing-737-86J/0114913/L/

And the hydraulic reservoir in question is on the right high up.

You have no idea how long I stared at that first photo.   
 
User avatar
HAWK21M
Posts: 29867
Joined: Fri Jan 05, 2001 10:05 pm

RE: 757 Wet Tail?

Wed Sep 28, 2011 8:50 am

Quoting Max Q (Reply 17):

How about a separate forum for them ?!

Always suggested to Anet admin in site related to have a Technical Photo section covering Maintenance in Hangars & component photos but alas..... 
I may not win often, but I damn well never lose!!! ;)
 
fadecfault
Posts: 65
Joined: Mon Nov 05, 2007 8:44 pm

RE: 757 Wet Tail?

Wed Sep 28, 2011 1:40 pm

Quoting boeing767mech (Reply 11):
E

Wow imagine if the tire and brake fell on a house...
The views and opinions written here are my own and do not reflect those of my employer.
 
User avatar
HAWK21M
Posts: 29867
Joined: Fri Jan 05, 2001 10:05 pm

RE: 757 Wet Tail?

Wed Sep 28, 2011 5:42 pm

Quoting boeing767mech (Reply 11):

Did they locate the Brake/MW......
I may not win often, but I damn well never lose!!! ;)
 
yeelep
Posts: 727
Joined: Mon Apr 04, 2011 7:53 pm

RE: 757 Wet Tail?

Thu Sep 29, 2011 5:09 am

Quoting tdscanuck (Reply 15):
You do see a lot of dirt in there after a while, but I've never heard of anything of substance getting jammed or otherwise causing damage. Because this area is on the trailing edge, it's pretty well sheltered from the airstream.

A much bigger horror from an exposure point of view is the 737 wheel well:
http://www.airliners.net/photo/Air-B...d=76aaf96ee85f426e555055b6fca5e11b

Not the flap well, but one of our planes had a writeup for a stiff speedbrake handle that couldn't be duplicated on the ground. A dead rat was eventually found wedged behind the ratio changer (upper right hand corner of the above link). On the ground the handle could be moved normally, at altitude the rat froze and interfered with the speedbrake input quadrant.
 
Max Q
Posts: 5644
Joined: Wed May 09, 2001 12:40 pm

RE: 757 Wet Tail?

Thu Sep 29, 2011 5:44 am

Quoting yeelep (Reply 24):


Not the flap well, but one of our planes had a writeup for a stiff speedbrake handle that couldn't be duplicated on the ground. A dead rat was eventually found wedged behind the ratio changer (upper right hand corner of the above link). On the ground the handle could be moved normally, at altitude the rat froze and interfered with the speedbrake input quadrant.

Nasty, but there are a lot more rats, dead and alive joining us on Aircraft around the world than we think !
The best contribution to safety is a competent Pilot.
 
yeelep
Posts: 727
Joined: Mon Apr 04, 2011 7:53 pm

RE: 757 Wet Tail?

Thu Sep 29, 2011 2:37 pm

Quoting boeing767mech (Reply 11):
Not a inside picture, but this is something we found during a overweight landing inspection.

Quoting boeing767mech (Reply 11):
They did a overweight landing inspection (so they say).

What would make you think they didn't perform the inspection. Unless the 757 manual is different than a 737NG in regards to the landing gear portion of an overweight landing inspection, the mechanics would not have been directed to remove the tire, brake and axle sleeve to inspect the axle.
 
boeing767mech
Topic Author
Posts: 805
Joined: Fri Dec 15, 2000 5:03 pm

RE: 757 Wet Tail?

Tue Oct 11, 2011 8:51 pm

Quoting yeelep (Reply 26):
What would make you think they didn't perform the inspection. Unless the 757 manual is different than a 737NG in regards to the landing gear portion of an overweight landing inspection, the mechanics would not have been directed to remove the tire, brake and axle sleeve to inspect the axle.

I'm quite aware what in done on a overweight landing having done many on every type of airplane in our fleet. It is just ironic that the VERY station that did the overweight landing inspection had the wheel and brake assy fly off and land at the end of the runway. As for questioning if it was done or not it was a joke. The person signed for it, so I hope it was done, if not and it was pencil whipped then he will have to anwser to the NTSB and FAA about that since it is in there hands now.

David
Never under-estimate the predictably of stupidty
 
MD11Engineer
Posts: 13916
Joined: Sun Oct 26, 2003 5:25 am

RE: 757 Wet Tail?

Wed Oct 12, 2011 7:09 am

Quoting boeing767mech (Reply 11):
All I can tell you is yes this is a 757. The airplane landed at another station to drop off a sick passenger. They did a overweight landing inspection (so they say). After leaving this station on the way here the ATC called and told the crew that they had left something behind. We did a fly by here in LAX and yes saw he was missing the #3 wheel and brake assy. The NTSB is still looking into this issue. So this is all I can tell you.....

David

I remember a similar issue with one of the nose wheels and it´s axle of a 737NG breaking off upon landing. The investigation revealed that weeks before a ramper, who wanted to attach a towbar in a rush situation accidentally had hit the nose wheel with the towbar when he approached the plane with his tractor (combined inertia of tractor and towbar). He informed MX, who replaced the nosewheel and did a visual inspection of the axle, but found nothing wrong. In fact, the impact had caused a miniature hairline crack (at this time only visible by NDT), which over the next few weeks became bigger and bigger with every landing until the exle broke off.

Jan
Je Suis Charlie et je suis Ahmet aussi
 
User avatar
HAWK21M
Posts: 29867
Joined: Fri Jan 05, 2001 10:05 pm

RE: 757 Wet Tail?

Wed Oct 12, 2011 10:50 am

Quoting MD11Engineer (Reply 28):
In fact, the impact had caused a miniature hairline crack (at this time only visible by NDT), which over the next few weeks became bigger and bigger with every landing until the exle broke off.

We had something similiar.....But after the Initial visual Inspection was followed later by an NDT.The Aircraft was only released thereafter.
I may not win often, but I damn well never lose!!! ;)

Who is online

Users browsing this forum: AA777223, Google [Bot] and 12 guests