UPS Pilot
Topic Author
Posts: 829
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777F Cargo Door?

Wed Jul 06, 2005 12:48 pm

I was looking at a 777F sales ad today. The Main deck cargo door is behind the wing rather in front. Nobody could answer why? The only freighter by Boeing, Airbus or MDD/Douglas to date is the 747. Thats because of the upper deck. I thought it would be weight distribution while loading. We have all seen MD-11's doing wheelies on the cargo ramp. The weight would still be in the rear of the aircraft coming in thru the cargo door. Does anybody know why Boeing would put the main deck door in the back?

The pic here shows the door but not to the extreme that I had seen in the sales ad.

www.boeing.com/commercial/777family/pf/pf_freighterback.html
 
FriendlySkies
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Joined: Fri Aug 13, 2004 3:57 pm

777F Cargo Door?

Wed Jul 06, 2005 12:54 pm

The 777 doesn't have a rear engine, so wheelies aren't really a problem. I'm sure Boeing put some thought into the location of the door, it may in fact be the best place for loading a 777.
 
PSAjet17
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Joined: Thu Dec 11, 2003 5:50 am

777F Cargo Door?

Wed Jul 06, 2005 12:58 pm

I would assume that when loading the upper deck, the pallets would be push forward and then the aft would be loaded. That should provide enough forward ballast to keep the aircraft from doing a wheelie.
 
pictues
Posts: 174
Joined: Tue Nov 09, 2004 11:41 am

777F Cargo Door?

Wed Jul 06, 2005 1:04 pm

Also there is a device called a tail stand to prevent that from happening, or they teather the nose wheel to the ground. Those were forgotten on the planes that went onto their tail.
 
ikramerica
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777F Cargo Door?

Wed Jul 06, 2005 1:08 pm

I would also assume the door could be placed up front, or a second door added, per operator demand, no?
Of all the things to worry about... the Wookie has no pants.
 
UPS Pilot
Topic Author
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777F Cargo Door?

Wed Jul 06, 2005 6:42 pm

The 777 has no rear engine, mmmm, I never knew that  Wink I'm aware of the loading methods and items used to prevent wheelies. The comment regarding wheelies and the cargo door was a speculation of why the door would be in the rear. The question is why would Boeing put the door there? The 747 has a reason to have the rear cargo door but all other freighters have the door ahead of the wing. MD11,DC-8, A300/310, 72, 75, 76 all have the door in front of the wing.
 
Shenzhen
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777F Cargo Door?

Wed Jul 06, 2005 7:06 pm

Could it be that when the cargo is loaded, it would need to be moved forward before the next pallet could be loaded, therefore the actual loading (except the first pallet) would be forward of the CG, not aft. With this in mind, there shouldn't be any willies.

Cheers
 
B707Stu
Posts: 893
Joined: Sat Feb 05, 2005 4:15 pm

777F Cargo Door?

Wed Jul 06, 2005 7:10 pm

Quoting Shenzhen (Reply 6):
With this in mind, there shouldn't be any willies.

That's the reason. Thanks Shenzhen, your "willies" for "wheelies" put a smile on my face.

 Big grin
 
Tod
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Joined: Sat Aug 28, 2004 6:51 am

777F Cargo Door?

Wed Jul 06, 2005 11:40 pm

Quoting UPS Pilot (Thread starter):
The Main deck cargo door is behind the wing rather in front. Nobody could answer why?

This allows one door design to be used on both freighter and combi configurations.
 
abirda
Posts: 296
Joined: Sat Jul 02, 2005 12:52 am

777F Cargo Door?

Thu Jul 07, 2005 1:45 am

Quoting PSAjet17 (Reply 2):
I would assume that when loading the upper deck, the pallets would be push forward and then the aft would be loaded. That should provide enough forward ballast to keep the aircraft from doing a wheelie.

My first thought exactly, although I'll take it a little further. With a cargo door forward of the wing, loaders must send the first pallets or containers to the rear of the aircraft and then work toward the front. this keeps the center of gravity as far aft as possible for as long as possible. With an aft cargo door like that depicted on the 777LRF, the first pallets or containers will be sent to the front of the aircraft to facilitate the continued loading of the aircraft. This, of course, will keep the center of gravity as far forward as possible for as long as possible. Kudos to Boeing for finding a simple way to insure against a load-induced tip of the plane.

Quoting Tod (Reply 8):
This allows one door design to be used on both freighter and combi configurations.

Not quite. For some time now it has been clear that the FAA will NOT certify any new designs for Combi aircraft due to the concern of increased risk to passengers' lives in the event of unplanned impacts that could jar the cargo loose.
 
N1120A
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777F Cargo Door?

Thu Jul 07, 2005 2:12 am

Quoting AbirdA (Reply 9):
Not quite. For some time now it has been clear that the FAA will NOT certify any new designs for Combi aircraft due to the concern of increased risk to passengers' lives in the event of unplanned impacts that could jar the cargo loose.

They will certify them with a fixed firewall between the two cabins. Still, unlikely a carrier would want that
Mangeons les French fries, mais surtout pratiquons avec fierte le French kiss
 
abirda
Posts: 296
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777F Cargo Door?

Thu Jul 07, 2005 2:26 am

Quoting N1120A (Reply 10):
They will certify them with a fixed firewall between the two cabins. Still, unlikely a carrier would want that

If that is true, my apologies for providing somewhat inaccurate info. I was under the impression that there was no way the FAA would be certifying the carriage of pax and freight on the same deck of any new design. Not doubting you, just curious to learn more about current Combi policies. Do you have a link to info on this, N1120A?
 
tribird1011
Posts: 196
Joined: Mon Mar 14, 2005 10:08 pm

RE: 777F Cargo Door?

Thu Jul 07, 2005 2:38 am

The B747 also doesn't have a rear engine, but...

http://www.airliners.net/open.file/065821/M/

As mentioned above, the reason for the wheelie was due to the lack of use of the tail-stand.
 
highflyer9790
Posts: 1189
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RE: 777F Cargo Door?

Thu Jul 07, 2005 2:50 am

Quoting UPS Pilot (Thread starter):
The only freighter by Boeing, Airbus or MDD/Douglas to date is the 747

If i understand this correctly, what about all the other frieghters????
757F
767F
etc.

did you mean with the cargo loading door in the rear?

Please clarify what you meant UPS Pilot
121
 
UPS Pilot
Topic Author
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RE: 777F Cargo Door?

Thu Jul 07, 2005 5:43 am

High Flyer, the 747 is the only heavy freighter with the door behind the wing instead of in front of it.

I figured out the reason (I think) It doesn't specify if it will use a 9 g net or a ridgid barrier between the flight deck and the cargo main deck. Looking at both the 9 g net would not allow for the stretch if needed between the cargo door and the flight deck. The ridgid barrier does not need the extra room but it does allow for more cargo space. This typically means there is one position to the left of the door on the main deck then all others are from the door down. It doesn't appear there is enough space to allow for this if the door is placed to the front of the wing.
 
Avianca
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RE: 777F Cargo Door?

Thu Jul 07, 2005 5:48 am

what kind of contur the 777 can be loaded? Q7 (MDSCD) buildet PMC´s or just Q6 ?
Colombia es el Mundo Y el Mundo es Colombia
 
LHZXF
Posts: 26
Joined: Fri May 27, 2005 2:23 am

RE: 777F Cargo Door?

Thu Jul 07, 2005 6:00 am

Many interesting points raised & discussed. I personally can't wait to see 777F in service.
 
Glom
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Joined: Sat Apr 23, 2005 2:38 am

RE: 777F Cargo Door?

Thu Jul 07, 2005 6:24 am

It says that the freighter has a range of less than 5000NM. I thought it was based on the 772LR?
 
abirda
Posts: 296
Joined: Sat Jul 02, 2005 12:52 am

RE: 777F Cargo Door?

Thu Jul 07, 2005 6:44 am

Quoting Glom (Reply 17):
It says that the freighter has a range of less than 5000NM. I thought it was based on the 772LR?

Dedicated freight aircraft, if i understand correctly, tend to dedicate a higher portion of their MTOW to fixed payload than do their passenger counterparts. Therefore, the maximum fuel load is decreased. In short, freight companies find it more desirable to carry larger weights over just marginally long distances rather than taking low loads over the longest routes.
 
ha763
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Joined: Mon Jan 06, 2003 5:36 pm

RE: 777F Cargo Door?

Thu Jul 07, 2005 8:02 am

Quoting AbirdA (Reply 11):
I was under the impression that there was no way the FAA would be certifying the carriage of pax and freight on the same deck of any new design. Not doubting you, just curious to learn more about current Combi policies.

Alaska had plans to convert 4 of their 737-400s into combi aircraft with a fixed configuration of 70 pax and 4 pallet positions.

http://www.alaskasworld.com/Newsroom...s/ASstories/AS_20040714_163719.asp

Considering that no 737-400 combis were built by Boeing, the converted 737-400s would need to be certified by the FAA. Alaska would not have considered it if there was no possibility of it being certified. They also considered the 737-700, which Boeing already makes in a fixed combi configuration for the US Navy or the 737-300, both which would have a fixed configuration of 70 pax and 3 pallet spaces. Again, it would not be considered as an option if the FAA wasn't going to certify it.
AS Eyeing B-737-200C Replacement (by EA CO AS Dec 26 2003 in Civil Aviation)
Alaska To Use Modified 734's To Replace 732 Combi (by ANC737 Jul 22 2004 in Civil Aviation)