Sponsor Message:
Aviation Technical / Operations Forum
My Starred Topics | Profile | New Topic | Forum Index | Help | Search 
Why No 3x4x2 Seating Instead Of 3x3x3?  
User currently offlineLAX888 From Singapore, joined Oct 2010, 279 posts, RR: 0
Posted (3 years 7 months 1 week 3 days 13 hours ago) and read 5717 times:

Hi everyone

I was wondering why planes with 9 seats across don't use the 3x4x2 arrangement? I remember SR/LX used to have it on their MD11 and if I am not mistaken NH has it now on their B773ER. However I would think that this is an attractive way to arrange the cabin since you can avoid the row with 5 seats and still can allow couples to fly together.

Thoughts? comments?

12 replies: All unread, jump to last
 
User currently offlinenws2002 From United States of America, joined Feb 2008, 897 posts, RR: 0
Reply 1, posted (3 years 7 months 1 week 3 days 7 hours ago) and read 5586 times:

IFE boxes can generally control three seats. So the 3-3-3 configuration requriers 3 boxes per row, and the 2-5-2 and 3-4-2 would require 4 boxes per row.

User currently offlineViscount724 From Switzerland, joined Oct 2006, 25300 posts, RR: 22
Reply 2, posted (3 years 7 months 1 week 3 days 4 hours ago) and read 5478 times:

Quoting LAX888 (Thread starter):
I remember SR/LX used to have it on their MD11

KL MD-11s were 2-4-3 until they switched to 3-3-3 a couple of years ago when they installed new seats and PTVs. Swissair was 3-4-2 on MD-11s (with the 3-seat unit on the left side, while on KL the 3 seat unit was on the right side).

Egyptair's 777-200ERs were 3-4-2 when delivered. Not sure whether that's been changed since. I belive MS is the only carrier with 3-4-2 on 777s.

747s were 3-4-2 for the first few years of service until demand started to pick up and they switched to 3-4-3.


User currently offlineMadDogJT8D From United States of America, joined Oct 2009, 397 posts, RR: 1
Reply 3, posted (3 years 7 months 1 week 3 days 1 hour ago) and read 5418 times:

A little over a decade ago, I flew on a Tradewinds L-1011 pax charter from JFK-CUN-JFK and one of their L-1011s (N75AA if I remember correctly) had a 3-4-2 layout and I remember thinking it was odd since one of their other L-1011s I flew was 2-5-2. So I guess my answer is that I've seen it done, but not in scheduled carrier ops.

User currently offlineAJ From Australia, joined Nov 1999, 2391 posts, RR: 24
Reply 4, posted (3 years 7 months 1 week 2 days 19 hours ago) and read 5259 times:

Quoting Viscount724 (Reply 2):
Egyptair's 777-200ERs were 3-4-2 when delivered. Not sure whether that's been changed since. I belive MS is the only carrier with 3-4-2 on 777s.

Still 3-4-2: http://www.egyptair.com/English/Pages/FleetDetails.aspx?Aircraft=11
Their -300ERs have 3-3-3: http://www.egyptair.com/English/Pages/FleetDetails.aspx?Aircraft=12


User currently offlineLIPZOAN From Italy, joined Jan 2011, 15 posts, RR: 0
Reply 5, posted (3 years 7 months 6 days 9 hours ago) and read 4783 times:

first i think made more easier for cabin crew to manage passenger needs,then 3-3-3 get easier to keep weight balanced along longitudinal axe

User currently offlinedeltamartin From Sweden, joined Dec 2010, 1061 posts, RR: 7
Reply 6, posted (3 years 7 months 6 days 8 hours ago) and read 4760 times:

Quoting Viscount724 (Reply 2):
KL MD-11s were 2-4-3 until they switched to 3-3-3 a couple of years ago when they installed new seats and PTVs. Swissair was 3-4-2 on MD-11s (with the 3-seat unit on the left side, while on KL the 3 seat unit was on the right side).

And AY's had 3-4-3 if im not mistaken.


User currently offlinebohica From United States of America, joined Feb 2004, 2699 posts, RR: 0
Reply 7, posted (3 years 7 months 6 days 8 hours ago) and read 4749 times:

The problem with a 3-4-2 configuration is that an airline has to buy a set of 2 seats, a set of 3 seats, and a set of 4 seats for each row. Multiply that times the number of rows in the airplane and it gets very expensive. I'm not even considering IFE boxes, overhead panels, spares, etc. It is much cheaper for an airline to have everything standardized with a 3-3-3 configuration where they only need to buy sets of 3 seats.

User currently offlineViscount724 From Switzerland, joined Oct 2006, 25300 posts, RR: 22
Reply 8, posted (3 years 7 months 6 days 3 hours ago) and read 4685 times:

Quoting deltamartin (Reply 6):
Quoting Viscount724 (Reply 2):
KL MD-11s were 2-4-3 until they switched to 3-3-3 a couple of years ago when they installed new seats and PTVs. Swissair was 3-4-2 on MD-11s (with the 3-seat unit on the left side, while on KL the 3 seat unit was on the right side).

And AY's had 3-4-3 if im not mistaken.

As I recall, at one time AY had a few MD-11s in high-density 3-4-3 layout in the entire cabin for use on charter-type routes. When they were retired they were 9-abreast (forget whether it was 3-4-2 or 2-4-3) in the forward Y class cabin and 10-abreast (3-4-3) in the rear cabin. Always seemed strange to have such a big difference in product on the same aircraft in the same class of service.


User currently offlineStarlionblue From Greenland, joined Feb 2004, 17038 posts, RR: 66
Reply 9, posted (3 years 7 months 6 days ago) and read 4643 times:

LIPZOAN,reply=5]first i think made more easier for cabin crew to manage passenger needs,then 3-3-3 get easier to keep weight balanced along longitudinal axe[/quote]

The balance thing is a non-issue. Look at all the DC-9 and MD-80s flying around with asymmetrical seating. It's a small amount of weight a very small distance from the centerline. Well within design limits.



"There are no stupid questions, but there are a lot of inquisitive idiots."
User currently offlinetod From Denmark, joined Aug 2004, 1725 posts, RR: 3
Reply 10, posted (3 years 6 months 3 weeks 5 days 10 hours ago) and read 4112 times:

Quoting bohica (Reply 7):
The problem with a 3-4-2 configuration is that an airline has to buy a set of 2 seats, a set of 3 seats, and a set of 4 seats for each row. Multiply that times the number of rows in the airplane and it gets very expensive. I'm not even considering IFE boxes, overhead panels, spares, etc. It is much cheaper for an airline to have everything standardized with a 3-3-3 configuration where they only need to buy sets of 3 seats.

L/H and R/H seat assemblies are already usually different part numbers.

Outboard PSU can be standardized with both sides configured for three.


User currently offlineMax Q From United States of America, joined May 2001, 4512 posts, RR: 18
Reply 11, posted (3 years 6 months 2 weeks 20 hours ago) and read 3545 times:

Quoting Starlionblue (Reply 9):
The balance thing is a non-issue. Look at all the DC-9 and MD-80s flying around with asymmetrical seating. It's a small amount of weight a very small distance from the centerline. Well within design limits.

Think about it. The seat arrangement is not actually assymetric at all. On the DC9/ MD80 the Aisle is what is offset. The aisle seat on the three side is on the centreline with the two seats either side 'balancing' the Aircraft



The best contribution to safety is a competent Pilot.
User currently onlinedoug_Or From United States of America, joined Mar 2000, 3407 posts, RR: 3
Reply 12, posted (3 years 6 months 2 weeks 8 hours ago) and read 3454 times:

Quoting Max Q (Reply 11):
The aisle seat on the three side is on the centreline with the two seats either side 'balancing' the Aircraft

If the aisle seat is on the centerline, then one side would have mean one side had 2 seats and the the other had two seats and an aisle. Since both sides are the same size and and all seats are the same width, this is impossible.



When in doubt, one B pump off
Top Of Page
Forum Index

Reply To This Topic Why No 3x4x2 Seating Instead Of 3x3x3?
Username:
No username? Sign up now!
Password: 


Forgot Password? Be reminded.
Remember me on this computer (uses cookies)
  • Tech/Ops related posts only!
  • Not Tech/Ops related? Use the other forums
  • No adverts of any kind. This includes web pages.
  • No hostile language or criticizing of others.
  • Do not post copyright protected material.
  • Use relevant and describing topics.
  • Check if your post already been discussed.
  • Check your spelling!
  • DETAILED RULES
Add Images Add SmiliesPosting Help

Please check your spelling (press "Check Spelling" above)


Similar topics:More similar topics...
Why No Extra "cockpit" Windows On The Top Of A-380 posted Tue May 27 2008 04:10:37 by L1011CPH
Loss Of Cabin Pressure, Why No Masks? posted Wed Apr 4 2007 22:45:35 by Boston92
Why No Direct Rnav Flights Over Land? posted Sat Nov 27 2010 02:03:06 by Dainan
Why No Winglets On Brand New 767 For JAL? posted Thu Nov 25 2010 14:01:25 by windshear
737NG: Why No IAE Engine Option? posted Sun Oct 10 2010 20:52:45 by KGRB
Why No Adjustable Lumbar Support On DL 77Ls In Y? posted Thu Sep 2 2010 13:13:40 by 1337Delta764
Escalators Instead Of Stairs posted Sun Aug 1 2010 20:00:21 by contrails67
No Lines Marking Edge Of Runway At YUL? posted Fri Jul 30 2010 09:08:49 by Evan767
Why No Psgr. Bay On Aircraft Like Space Shuttle? posted Mon Jul 5 2010 18:04:54 by rightrudder
Crashes And Near Misses: Why No Footage Available? posted Mon Jun 7 2010 07:54:08 by alwaysontherun

Sponsor Message:
Printer friendly format