Sponsor Message:
Aviation Technical / Operations Forum
My Starred Topics | Profile | New Topic | Forum Index | Help | Search 
747-400 Mtow Differences  
User currently offlineXerses From United States of America, joined Jun 2008, 6 posts, RR: 0
Posted (6 years 3 months 3 days 4 hours ago) and read 8022 times:

The 747-400 Airport planning document gives max take off weights of 800,000lb to 875,000lbs. Why are there different reported weights? Is the structure different? I know the domestic version has smaller tires and the SP actually has a shorter MLG bogey.

Is there a database/spreadsheet that compares the differences for 747s?

23 replies: All unread, jump to last
 
User currently offlinePhilSquares From , joined Dec 1969, posts, RR:
Reply 1, posted (6 years 3 months 3 days 3 hours ago) and read 8012 times:



Quoting Xerses (Thread starter):
The 747-400 Airport planning document gives max take off weights of 800,000lb to 875,000lbs.

On the 744, it's just an issue with paperwork. If you want the 875,000 weight, you pay more. If not, you don't pay any extra. There are no structural differences at all between the gross weights. The same was true on the 747-200A/B.


User currently offlinePoint8six From United Kingdom, joined Apr 2008, 94 posts, RR: 0
Reply 2, posted (6 years 3 months 3 days 1 hour ago) and read 7976 times:

Some -400's (BA's 'lites') were delivered without stab. tank capability and had a lower MGTOW. Aware of Japan's 'domestic' version, but I thought the 'SP' was a Classic version? Also 400F's have the lower( as for 'Lite') MGTOW as they do not use a stab. tank.The latest 400ERF has a MGTOW of approx 915000lbs.

User currently offlineCaryjack From United States of America, joined May 2007, 332 posts, RR: 0
Reply 3, posted (6 years 3 months 2 days 21 hours ago) and read 7933 times:



Quoting Xerses (Thread starter):
max take off weights

MTOW, right?

Quoting PhilSquares (Reply 1):
the gross weights



Quoting Point8six (Reply 2):
a MGTOW

We went from MTOW to MGTOW. What's the difference please?  confused 
Thanks,
Cary


User currently onlineViscount724 From Switzerland, joined Oct 2006, 25332 posts, RR: 22
Reply 4, posted (6 years 3 months 2 days 21 hours ago) and read 7929 times:



Quoting Xerses (Thread starter):
know the domestic version has smaller tires

The 744D also lacks the wingtip extensions and winglets. It has the same wingspan as the 741/742/743, about 16 ft. less than other 744 models. The wintip extensions and winglets can be added to the 744D if a carrier wanted to use it in longhaul operations.


User currently offlineXerses From United States of America, joined Jun 2008, 6 posts, RR: 0
Reply 5, posted (6 years 3 months 2 days 19 hours ago) and read 7906 times:

Thanks for the info on the Domestic, but I'm mostly interested in the plain old -400. The 747-400 Airplane Characteristics for Airport Planning document (D6-58326-1) found on the boeing web site gives several Max Design Takeoff Weights for the regular 747-400 on page 10 of 800,000lbs, 833,000, 850,000, 870,000 and 875,000. PhilSquares says its for people to just pay more. Does anyone have a reference that supports that? I was wondering if it was due to internal arrangements that shifts the CG and thus limits the Max weight. Or perhaps there are slightly different wing or gear structural components. My final thought was that a lower placarded MTOW and MLW may give more cycles on the gear and airframe.

My flight sim is way out of date, I was wandering if anyone with newer versions or add ons has different 747-400 that have MTOW like those above?

Anyone else have a good theory or a quote from a coffee table book?

I saw one interesting side note in "http://www.airliners.net/aircraft-data/stats.main?id=100", It mentions, "The -400ER incorporates the strengthened wing, body, and landing gear of the -400F" which in turn is quoted from The International Directory of Civil Aircraft by Gerard Frawley.

That indicates to me that there are some differences between the 747-400 and 400F but that is interesting because those two aircraft have the same MTW, and MTOW but the -400F has MLW that is 36,000 lbs greater than the 400. That makes me go hmmmmmmm.

Cary, I believe MTOW and MGTOW are the same thing. It depends on the company. I think that manuals giving generic info like the one I mention above actually calls it the Maximum Design Take Off Weight, but in actual flight manuals it just says Maximum Takeoff Weight. Gross is an older term, I've heard people refer to an aircraft's MGW (Max Gross Weight) or just max gross but what they mean is the maximum weight that you can begin to fly. Another term for the same thing is Maximum Weight at Brake Release.


User currently offlineStarlionblue From Greenland, joined Feb 2004, 17039 posts, RR: 66
Reply 6, posted (6 years 3 months 2 days 19 hours ago) and read 7900 times:



Quoting Xerses (Reply 5):
That indicates to me that there are some differences between the 747-400 and 400F but that is interesting because those two aircraft have the same MTW, and MTOW but the -400F has MLW that is 36,000 lbs greater than the 400. That makes me go hmmmmmmm.

As you say F has strengthened wing, gear and body. The max take off weight will be the same. You can just take less fuel. However you can land with heavier payload.



"There are no stupid questions, but there are a lot of inquisitive idiots."
User currently offlineMarkC From United States of America, joined Apr 2006, 259 posts, RR: 0
Reply 7, posted (6 years 3 months 2 days 19 hours ago) and read 7899 times:

Same with the engines. If you wanted PW4060's instead of 4056's, you would have to pay for the extra 4000 pounds. Its the same engine except for the program plug.

User currently offlineXerses From United States of America, joined Jun 2008, 6 posts, RR: 0
Reply 8, posted (6 years 3 months 2 days 18 hours ago) and read 7895 times:

Is that how you get more MTOW by having higher rated engines? I did see in the 747-100 airplane characteristics document that the the MTOW seemed to be tied directly to the version of the JT9, but the 5 weights I stated before are the same for the PW4056, CF6-80C2B1, and the RB211-524G2 engines.

Is there a book or paper available that talks specifically about the differences like the the wing and gear on the F?


User currently offlineTdscanuck From Canada, joined Jan 2006, 12709 posts, RR: 79
Reply 9, posted (6 years 3 months 2 days 18 hours ago) and read 7891 times:



Quoting Xerses (Thread starter):
The 747-400 Airport planning document gives max take off weights of 800,000lb to 875,000lbs. Why are there different reported weights?

At least part of it is the different engines. Different thrusts give you different MTOW's.

Quoting Xerses (Thread starter):
Is the structure different?

The struts and nacelles are different depending on whose engine it is.

Quoting Xerses (Thread starter):
Is there a database/spreadsheet that compares the differences for 747s?

I'm sure there is, but I've never seen one publicly available.

Quoting Xerses (Reply 5):
I was wondering if it was due to internal arrangements that shifts the CG and thus limits the Max weight.

I'm not aware of any aircraft whose MTOW is caused by a CG limit...you can always rearrange the same payload weight to move the CG.

Tom.


User currently onlineFlighty From United States of America, joined Apr 2007, 8541 posts, RR: 2
Reply 10, posted (6 years 3 months 2 days 17 hours ago) and read 7881 times:

Who has the most capable 744s in existence? 875k weights and so on? Does UA? NW?

User currently offlineMax Q From United States of America, joined May 2001, 4521 posts, RR: 18
Reply 11, posted (6 years 3 months 2 days 16 hours ago) and read 7868 times:

Must be QF with their 910,000lb -400-ER'S


The best contribution to safety is a competent Pilot.
User currently offlineQantas744ER From United States of America, joined Jun 2005, 1286 posts, RR: 4
Reply 12, posted (6 years 3 months 2 days 7 hours ago) and read 7798 times:



Quoting Point8six (Reply 2):
Also 400F's have the lower( as for 'Lite') MGTOW as they do not use a stab.

Wrong, depending from airline, but for example atlas air have the max available MTOW on all their 74F's of 875,000Lbs. The 74F can have the same MTOW options like the 744 just without the stab tank.

Leo

Quoting Flighty (Reply 10):
Who has the most capable 744s in existence? 875k weights and so on? Does UA? NW?

I wouldnt directly say most capable, as airlines buy their planes adapted to their needs. This is a main factor on engines choices etc.

But if you want to know some 875k operators:

UA
NW
SQ on their 744 (their 74F have 870k)
5Y
PO
CX
NH

and the list goes on...



Happiness is V1 in Lagos
User currently offlineCaryjack From United States of America, joined May 2007, 332 posts, RR: 0
Reply 13, posted (6 years 3 months 2 days 2 hours ago) and read 7757 times:



Quoting Xerses (Reply 5):
I believe MTOW and MGTOW are the same thing

Thanks Tim. You're off to a good start with interesting and informative posts. I'm looking forward to reading many more. Welcome to A.net.
Cary


User currently offlineTito From United States of America, joined Feb 2001, 125 posts, RR: 1
Reply 14, posted (6 years 3 months 1 day 23 hours ago) and read 7728 times:

Quoting Qantas744ER (Reply 12):
But if you want to know some 875k operators:

UA
NW
SQ on their 744 (their 74F have 870k)
5Y
PO
CX
NH

and the list goes on...

Just FYI, CX 400F's are 870k MTOW

[Edited 2008-06-19 15:12:46]

User currently offlineXerses From United States of America, joined Jun 2008, 6 posts, RR: 0
Reply 15, posted (6 years 3 months 1 day 22 hours ago) and read 7711 times:

Where do you find info like who are the 875k operators? is there a document? a web source?

User currently offlineXerses From United States of America, joined Jun 2008, 6 posts, RR: 0
Reply 16, posted (6 years 3 months 1 day 21 hours ago) and read 7702 times:

Are all of United's aircraft 875k?

User currently offlineTdscanuck From Canada, joined Jan 2006, 12709 posts, RR: 79
Reply 17, posted (6 years 3 months 1 day 20 hours ago) and read 7691 times:



Quoting Xerses (Reply 15):
Where do you find info like who are the 875k operators? is there a document? a web source?

Probably not. There are web sources where you could find which ones were delivered as 875k but, since there are Service Bulletins out there to switch it around, it would be impossible to know which ones are currently 875k without contacting each individual operator and asking them. There is no central database to tell you the current SB status of any particular aircraft.

Tom.


User currently offlineQantas744ER From United States of America, joined Jun 2005, 1286 posts, RR: 4
Reply 18, posted (6 years 3 months 1 day 19 hours ago) and read 7680 times:



Quoting Tdscanuck (Reply 17):
Probably not. There are web sources where you could find which ones were delivered as 875k but, since there are Service Bulletins out there to switch it around, it would be impossible to know which ones are currently 875k without contacting each individual operator and asking them. There is no central database to tell you the current SB status of any particular aircraft.

Tom.

http://www.buchair.com/JPAF.htm Book gets updated every year with aircraft registration data from 99% of the countries, so the MTOW data for most aircraft is correct!

This is my main source. Not always correct but personal knowledge is always available too.

Well it aint hard to find out about 870k or 875k since these changes are not simply made from day to day basis, and knowing a UA pilot in this case would be enough if regarding UA for example.

Quoting Xerses (Reply 16):
Are all of United's aircraft 875k?

Correct and since delivery.

In some countries like the the UK the CAA has a online register giving you a lot of info when you enter the UK reg.

Like current MTOW, Hours, etc.

Have a good one  Smile



Happiness is V1 in Lagos
User currently offlineTdscanuck From Canada, joined Jan 2006, 12709 posts, RR: 79
Reply 19, posted (6 years 3 months 1 day 16 hours ago) and read 7657 times:



Quoting Qantas744ER (Reply 18):
http://www.buchair.com/JPAF.htm Book gets updated every year with aircraft registration data from 99% of the countries, so the MTOW data for most aircraft is correct!

They're seriously polling every operator every year to find out which SB's they've done? And the operators actually supply this data reliably?

Tom.


User currently offlineQantas744ER From United States of America, joined Jun 2005, 1286 posts, RR: 4
Reply 20, posted (6 years 3 months 1 day 5 hours ago) and read 7592 times:



Quoting Tdscanuck (Reply 19):
They're seriously polling every operator every year to find out which SB's they've done? And the operators actually supply this data reliably?

Tom.

It is done by certain people that handle their countries data, this info does not need to come directly for the operator as some countries provide this information for the public. So its around 99% correct as during the the year some aircraft receive MTOW changes...


Leo  Smile



Happiness is V1 in Lagos
User currently offlineDispatchguy From United States of America, joined Jan 2006, 1249 posts, RR: 2
Reply 21, posted (6 years 3 months 1 day 4 hours ago) and read 7584 times:



Quoting Xerses (Reply 5):
PhilSquares says its for people to just pay more. Does anyone have a reference that supports that?

That is standard industry wide.

When I dispatched at a BAe146 operator a long time back, we had one airplane (N632AW, a B146-100) that had the authorization for a 15kt tailwind takeoff in the Airplane Flight Manual and the Operations Specifications, and only at Aspen Airport (KASE). We had a specific appendix to the AFM with the specific performance charts for that condition.

I asked why the reasons for only one airport and for only one airplane. Company didnt want to pay for the engineering work to have it done and approved for the rest of the -146 fleet.; especially for 3 variants of the fleet, for the engineering work would have to be done for each individual variant.

Most basic Boeing AFMs (regardless of aircraft type) limit takeoff field elevation to 8400-8500ft, but yet Boeing airplanes operate daily down in South America with some field elevations well above 10K. Those carriers paid for the additional engineering work to have higher field elevations approved and put into the AFM.



Nobody screws you better than an airline job!
User currently onlineViscount724 From Switzerland, joined Oct 2006, 25332 posts, RR: 22
Reply 22, posted (6 years 3 months 21 hours ago) and read 7525 times:



Quoting Qantas744ER (Reply 18):
In some countries like the the UK the CAA has a online register giving you a lot of info when you enter the UK reg.

Like current MTOW, Hours, etc.

I think the hours shown in the UK CAA registration info is only since the C of A was last renewed so it's often not very useful. For example, for the following BA 744, the hours are as of December 2004. The C of A expires this August.
http://www.caa.co.uk/application.asp...detailnosummary&fullregmark=G-CIVK

However the UK registration info does seem more informative than the equivalent FAA data. The UK info includes MTOW and even photos of the aircraft, with links to a list of updates to the flight manual etc.

This is an example of the FAA registration info for a UA 744.
http://registry.faa.gov/aircraftinquiry/NNumSQL.asp?NNumbertxt=198UA


User currently offlineTdscanuck From Canada, joined Jan 2006, 12709 posts, RR: 79
Reply 23, posted (6 years 3 months 20 hours ago) and read 7519 times:



Quoting Qantas744ER (Reply 20):
It is done by certain people that handle their countries data, this info does not need to come directly for the operator as some countries provide this information for the public.

Must be different than in the US. As far as I know, there's no requirement for operators to report SB incorporation to the regulators here.

Tom.


Top Of Page
Forum Index

Reply To This Topic 747-400 Mtow Differences
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...
Boeing 747-400 Reverse Thrust? posted Thu Mar 20 2008 14:50:49 by Kimberlyrj
747 400 Speed posted Mon Sep 10 2007 12:52:19 by AussieBob
SQ 747-400: No Speed Brakes Deployed On Landing. posted Fri Aug 17 2007 02:22:13 by Qslinger
747-400 Auto Brake Question. posted Sat Jun 23 2007 23:38:21 by Bobbidooley
B 747-400 Engines Off posted Thu May 24 2007 17:12:32 by Radimz
Expected Operating Data 747-8i V 747 400 posted Tue May 8 2007 18:10:01 by SunriseValley
Creaking Sounds On 747-400 Nose Gear posted Sat Mar 24 2007 17:58:59 by 744lover
747-400 Flight Deck Question posted Wed Dec 27 2006 16:07:42 by Gkyip
Slat Retraction During Reverse Thrust? 747-400 posted Sun Nov 5 2006 00:29:24 by Ajaaron
Is Re-engining A 747-400 With Trent 500s Possible? posted Sat Nov 4 2006 22:59:28 by LTU932

Sponsor Message:
Printer friendly format