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Topic: Question About The MD-11 Empennage
Username: alwaysontherun
Posted 2010-09-14 08:50:36 and read 8456 times.

For those in the know:

Looking at the pic below today I noticed that the MD-11 vertical stabilizer consists of many "patches"……I put some green dots on the pic to indicate what I mean:


The sting is in the tail


Why is that??
The 747 tail looks so "clean" compared to the MD-11.

2nd question, where I painted my red dot--> what´s the purpose of that fin please?
Has it something to do with guiding the thrust from #2 engine??
Cheers!

Regards,

###"I´m always on the Run"###

Topic: RE: Question About The MD-11 Empennage
Username: 474218
Posted 2010-09-14 09:20:54 and read 8439 times.

Those are access panels, not patches. There are components inside that require being accessed periodically.

Topic: RE: Question About The MD-11 Empennage
Username: nicoeddf
Posted 2010-09-15 07:48:37 and read 8202 times.

...and actually I think, the paint job of the 747 is just way newer. So the perceived "patching" is just more visibile through already faded paint and dirt accumulation.

Topic: RE: Question About The MD-11 Empennage
Username: tdscanuck
Posted 2010-09-15 09:27:39 and read 8158 times.

Quoting nicoeddf (Reply 2):
...and actually I think, the paint job of the 747 is just way newer. So the perceived "patching" is just more visibile through already faded paint and dirt accumulation.

Indeed. Here's the access panel diagram for a 747-400 fin:
http://img695.imageshack.us/img695/2885/747400fin.jpg

Tom.

Topic: RE: Question About The MD-11 Empennage
Username: tsugambler
Posted 2010-09-15 10:03:13 and read 8137 times.

Quoting alwaysontherun (Thread starter):
2nd question, where I painted my red dot--> what´s the purpose of that fin please?
Has it something to do with guiding the thrust from #2 engine??

That "fin" is actually the engine pylon... it's part of the one-piece "banjo" structure that supports the vertical stabilizer. The #2 engine is actually "hanging" from that pylon, just like the #1 and #3 engine are hanging from the wing-mounted pylons. As to why it has to be that particular length, I have no idea--perhaps it's something to do with airflow and drag.

Topic: RE: Question About The MD-11 Empennage
Username: HAWK21M
Posted 2010-09-15 10:45:09 and read 8114 times.

Those "patches" are actually Access panels used to access areas during routine Inspection/servicing.Once opened they tend to leave a visible borderline over time if a new paint job is not carried out or aircraft not cleaned.
regds
MEL.

Topic: RE: Question About The MD-11 Empennage
Username: etherealsky
Posted 2010-09-15 17:35:39 and read 8027 times.

I've been trying to find a good photo of it or a link to more info (no luck so far), but on the King Air 200 I believe the tail section is life-limited as an assembly, however there is an STC out there that removes this limitation with the installation of inspection panels that run vertically along the tail spar.

Topic: RE: Question About The MD-11 Empennage
Username: alwaysontherun
Posted 2010-09-19 06:59:59 and read 7626 times.

Quoting tdscanuck (Reply 3):
Here's the access panel diagram for a 747-400 fin:

A picture tells a 1000 words………..

I´m amazed by the amount of access panels!!
Entrance is normally only required during the heavier checks, I imagine.
I have never seen anybody accessing a plane´s fin at a gate for instance.

Quoting tsugambler (Reply 4):
That "fin" is actually the engine pylon.
Quoting tsugambler (Reply 4):
As to why it has to be that particular length, I have no idea--perhaps it's something to do with airflow and drag.

Now if you look right under the Dutch and the European flag of the 2nd plane (B744) in the pic, like right below it; there´s a horizontal recess in the MD11´s pylon--> like a horizontal hole of about a meter--> does anybody know what´s that for?

Cheers,

###"I´m always on the Run"###

Topic: RE: Question About The MD-11 Empennage
Username: tdscanuck
Posted 2010-09-19 07:10:41 and read 7623 times.

Quoting alwaysontherun (Reply 7):
Entrance is normally only required during the heavier checks, I imagine.
I have never seen anybody accessing a plane´s fin at a gate for instance.

The big panels between the leading edge of the rudder and trailing edge of the fin might come off at a gate if doing hydraulic work on the rudder (replacing a PCU, etc.), but that's about it. Most of the others are for accessing the internal structure (heavy check).

Tom.

Topic: RE: Question About The MD-11 Empennage
Username: alwaysontherun
Posted 2010-09-22 19:57:16 and read 7296 times.

Quoting tdscanuck (Reply 8):
Most of the others are for accessing the internal structure (heavy check).

Interesting that KLM did not patch up the paint work after a heavy check........it takes 1 man, 1 brush, and a ladder! No?

Thanks anyway!!


###"I'm always on the Run"###

Topic: RE: Question About The MD-11 Empennage
Username: SchorschNG
Posted 2010-09-25 04:18:59 and read 7045 times.

Quoting tsugambler (Reply 4):
That "fin" is actually the engine pylon... it's part of the one-piece "banjo" structure that supports the vertical stabilizer. The #2 engine is actually "hanging" from that pylon, just like the #1 and #3 engine are hanging from the wing-mounted pylons. As to why it has to be that particular length, I have no idea--perhaps it's something to do with airflow and drag.

As the engine is much cleaner than the rest, it is pretty easy to see where the engine is located. Thanks for that info.
The rear extension is maybe required to keep commonality to the usual underwing engine ... or not.

Topic: RE: Question About The MD-11 Empennage
Username: TravelAVNut
Posted 2010-09-25 08:27:31 and read 6961 times.

Quoting tsugambler (Reply 4):
The #2 engine is actually "hanging" from that pylon, just like the #1 and #3 engine are hanging from the wing-mounted pylons.

These are the pieces of information that make this forum great   I learn something everyday, thanks tsugambler!

Topic: RE: Question About The MD-11 Empennage
Username: wn700driver
Posted 2010-09-25 20:03:15 and read 6878 times.

Quoting HAWK21M (Reply 5):
Once opened they tend to leave a visible borderline over time if a new paint job is not carried out or aircraft not cleaned.
regds

Damned PRC Sealants!

Quoting alwaysontherun (Reply 7):
I have never seen anybody accessing a plane´s fin at a gate for instance.

I've done just that myself on a few occasions. Usually to inspect or R&R a leaky actuator/actuator seal for example

Quoting alwaysontherun (Reply 9):

Interesting that KLM did not patch up the paint work after a heavy check........it takes 1 man, 1 brush, and a ladder! No?

Erm, no. Often the mfr just has the seals & screws just painted over (In fact I've never seen livery color coordinated screws now that I think of it...) So, after popping the cherry on that panel, it will be visible until the AC is painted again...

As for "brushing" the surface... Not really practical. It looks a bit smaller in a photograph, but those tails get pretty big when you're up close. Of course you always clean up after your own work, but cleaning an entire stabilizer so that everything matches would easily take more than your entire shift (or two!), if it's just one person doing it. That's a lot of metal up there!

Topic: RE: Question About The MD-11 Empennage
Username: fr8mech
Posted 2010-09-25 21:36:00 and read 6863 times.

Quoting alwaysontherun (Reply 7):

Now if you look right under the Dutch and the European flag of the 2nd plane (B744) in the pic, like right below it; there´s a horizontal recess in the MD11´s pylon--> like a horizontal hole of about a meter--> does anybody know what´s that for?

If I understand your location, you're asking about the pre-cooler exhaust for the number 2 pnuematic system.

Topic: RE: Question About The MD-11 Empennage
Username: aerdingus
Posted 2010-09-26 02:56:00 and read 6812 times.

The reverser actually looks really clean in this pic. I wonder if it had recently been worked on/replaced.

Topic: RE: Question About The MD-11 Empennage
Username: HAWK21M
Posted 2010-09-26 04:44:58 and read 6790 times.

Quoting wn700driver (Reply 12):

Damned PRC Sealants!

True.Especially if theres a lack of time for the PRC to dry up.
regds
MEL.

Topic: RE: Question About The MD-11 Empennage
Username: alwaysontherun
Posted 2010-09-26 20:07:01 and read 6667 times.

Quoting fr8mech (Reply 13):
If I understand your location, you're asking about the pre-cooler exhaust for the number 2 pnuematic system.

I guess I did----> thank you for pointing that out. Now I know..........

Quoting wn700driver (Reply 12):
I've done just that myself on a few occasions. Usually to inspect or R&R a leaky actuator/actuator seal for example

Well, you never did when I was around............just so you know!!

Quoting wn700driver (Reply 12):
As for "brushing" the surface... Not really practical. It looks a bit smaller in a photograph, but those tails get pretty big when you're up close. Of course you always clean up after your own work, but cleaning an entire stabilizer so that everything matches would easily take more than your entire shift (or two!), if it's just one person doing it. That's a lot of metal up there!

Fair enough!

I guess I'd love your job, you need anyone with 2 left hands, perhaps?

###"I'm always on the Run"###


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