Re: B777-300/B777-300ER???

Date:         13 Jan 99 02:13:32 
From:         Lukas Lusser <lusser@ubaclu.unibas.ch>
Organization: Europainstitut Basel
References:   1
Followups:    1 2
Next article
View raw article
  or MIME structure

Hi all,

the suffix "IGW" seems to be used inofficially (by airlines and possibly
also by Boeing) for B777s certified to Increased Gross Weight
operations, meaning the aircraft is externally similar to the "normal"
version but is in its documents certified to fly with higher weights
than the base model. I'm not familiar with the structural requirements
for a 777 to become an "IGW" model, but I recall having read proud
announcements of at least two airlines already operating a number of
base model 777s that they were taking over their first IGW 777s. These
airlines were Emirates, who circulated this message in the press upon
taking delivery of their (if my brains remember it right) fourth 777-200
A6-EMG, thus making A6-EMD/E/F normal 777s. I also recall that British
Airways once mentionned taking delivery of IGW 777's, and in the back of
my mind I also wonder if Cathay Pacific did not also at least consider
to follow this approach.

Note that IGW does not necessarily mean that there is more fuel capacity
nor that the maximal range is augmented over the base model. Higher
weights can just mean that you get a more favourable trade off between
payload restrictions applying and fuel quantity required when you're
flying on route segments approaching the range/payload limits of the
aircraft. No aircraft goes the maximum range with maximal load, as you
would for sure exceed the MTOW (Maximum Take Off Weight) and thus
compromise operating safety when you try to do so (ok, some guys tried
before, and not all got away with it, but that's a different story).

And also remember that it certifying existing types to higher weights is
not a new story at all. The MTOW for B747-200Fs and for B747-400Fs (just
as an example) could be raised some way down the production process. I
definitely recall that Luxemburg based cargo operator Cargolux was VERY
proud to be the first airline to receive a 747 with a MTOW above 320'000
metric tons (and a maximal payload of above 100'000 metric tons) when
they took delivery of their first new B747-200F in the early eighties.
At this time, the B747-200 had been around for over 10 years.

If I find out more about the above mentionned 777 IGW customers, I'll
post a follow-on, but this will not be possible before mid January.

Hope it helps, and have a nice weekend

Lukas Lusser