What are the differences?

[qantas747 4]

Hey all,

 

With the pending release of the 777-200LR/F, and hopefully the -300/ER along with the -200/ER at some point, I was wondering what are the cockpit and systems differences between the earlier models and later models.

 

There are the different engine options, different weights, different sizes and different ranges, but what are the less notable differences between them all buried in the systems? I may have this all wrong but I remember hearing that there were differences between them all.

 

Thanks!

[Richard McDonald Woods 168]

Hi Oliver,

 

I have found the SmartCockpit documentation for the B777 most helpful, but inevitably quite a lot of reading.

 

Cheers, R

[machine2035 176]

Hey all,

 

With the pending release of the 777-200LR/F, and hopefully the -300/ER along with the -200/ER at some point, I was wondering what are the cockpit and systems differences between the earlier models and later models.

 

There are the different engine options, different weights, different sizes and different ranges, but what are the less notable differences between them all buried in the systems? I may have this all wrong but I remember hearing that there were differences between them all.

 

Thanks!

The few main differences I can think of are;

 

• The main one discussed around here, the taxi cam (or technically called the Ground Maneuver Camera System) - GMCS is only featured on the 300/300ER.

 

• The 300ER also features a tail-strike protection system. If a tailstrike is detected to be imminent, back pressure will be released automatically to reduce the chance of a tailstrike (I am not too sure if this is shared across the whole T7 fleet, or just to the 300/300ER fleet).

 

• There is obviously some differences between the -F and the pax versions. Such things include overhead panel differences (Supernumary Pax Signs, Environmental Control System etc.). There are also numerous differences on the synoptic pages.

Those are some of the differences I could come up with off the top of my head, but as Richard posted above, you can find alot of helpful information on Smartcockpit and with simple google searches - There is a lot of info on the T7 out on the WWW (World Wide Web).

[Datalink 26]

Another difference is the landing gear, the -300ER having the semi-levered gear and the -200LR/F having the same strut but not the hydraulic cylinder (?)

[Paul Curtis 23]

I always wonder why 777-200F has considerably shorter range than 200LR :unsure:

[johnsturm 22]

I always wonder why 777-200F has considerably shorter range than 200LR :unsure:

 

The 200LR can be fitted with an optional 3 additional fuel tanks giving it a max fuel capacity of 53,515 US gal compared to the basic 200LR and 200F which only have a 47,890 US gal fuel capacity.

 

References:

http://www.boeing.com/boeing/commercial/777family/pf/pf_lrproduct.page?

http://www.boeing.com/boeing/commercial/777family/pf/pf_freighter_product.page?

[Paul Curtis 23]

The 200LR can be fitted with an optional 3 additional fuel tanks giving it a max fuel capacity of 53,515 US gal compared to the basic 200LR and 200F which only have a 47,890 US gal fuel capacity.

 

References:

http://www.boeing.com/boeing/commercial/777family/pf/pf_lrproduct.page?

http://www.boeing.com/boeing/commercial/777family/pf/pf_freighter_product.page?

200f has same fuel capacity as 300ER but same MTOW as 200LR?

[Morvious 43]

The 200LR can be fitted with an optional 3 additional fuel tanks giving it a max fuel capacity of 53,515 US gal compared to the basic 200LR and 200F which only have a 47,890 US gal fuel capacity.

 

References:

http://www.boeing.com/boeing/commercial/777family/pf/pf_lrproduct.page?

http://www.boeing.com/boeing/commercial/777family/pf/pf_freighter_product.page?

But the 6000 US Gal is not the 4000 nM difference alone? What makes the 77F so fuel hungry? Or is it a mistake on the site?

[johnsturm 22]

But the 6000 US Gal is not the 4000 nM difference alone? What makes the 77F so fuel hungry? Or is it a mistake on the site?

 

I am not claiming to be an expert, just linking information provided by Boeing. One thing you have to consider is that all of the 47,890 gallons of fuel is not usable. They have to account for legal reserves, contingency fuel, etc. But the entire 5,625 gallon difference IS usable because the legal reserves and contingency fuel is accounted for in that same first 47,890 gallons. That will account for a big chunk of it but there may be other performance differences, I honestly don't know.

[ijorge511 44]

Maybe that's based on a full payload on the Freighter of 112 tons?

[Paul Curtis 23]

Maybe that's based on a full payload on the Freighter of 112 tons?

Yes but it has same MTOW as 200LR!!

[Captain Kevin 586]

Yes but it has same MTOW as 200LR!!

I'm going to see if I can try to make some sense out of this for you. Both airplanes have the same maximum take-off weight, but if you go by Boeing's 3-class configuration of 301 passengers, we assume one passenger weighs 170 pounds, that's a total of 51,170 pounds. Let's say the passengers then also have two bags each weighing 50 pounds, so add another 30,100 pounds. That's a total of 81,270 pounds that the Boeing 777-200LR is carrying. Take 766,000 pounds, subtract the payload of 81,270 pounds, subtract the airplane's weight of 320,000, and you can carry 364,730 pounds of fuel, or about 54,682 gallons of fuel, assuming it had that kind of fuel capacity, which it doesn't.

 

Now if we go to the 777-200F, it can carry a payload of 112 tons, which is 224,000 pounds of payload. Take the same 766,000 pounds, subtract the 224,000 pounds, subtract the airplane's empty weight of 318,300 pounds, and you can carry 223,700 pounds of fuel, or about 33,538 gallons of fuel. As you can see, you can carry far less fuel with the -200F than you can with the -200LR. It's a trade-off between payload and range.

[adamant365 28]

AirKevin is correct.

 

The Boeing range charts for the 777F consider the aircraft stuffed to maximum ZFW with cargo which means the weight available for fuel before reaching MTOW is much less than the maximum fuel capacity.

 

The charts for the 777-200LR consider the aircraft full of passengers, but the total payload puts the aircraft far enough below maximum ZFW that the fuel load can be 100% without busting through MTOW.

[Morvious 43]

Thank you

[Paul Curtis 23]

That makes more sense :mellow: