Phosphorus wrote:bikerthai wrote:DL757NYC wrote:They should procure Ex pax 747-400’s that are late build low time/cycle frames. There out there how long they remain nobody knows. The E-4 will have to be replaced at some point.
The cost saving from using a -400 will be negated by the additional engineering cost to "militarize the the model".
Much of the militarization designed for the -8 under the VC-25B and can be re-used.
Note that airframe design is only part of the cost. Much the the electronic rack design for VC-25B can be re-used for any 747-8 based E-4.
The other aspect of design is the 747-8 is a digigtal airplane, so engineering for the mod is easier.
The -400 may not have complete digital definition. And I'm pretty sure what they have would be in the old version of CATA (V-4 vs V5).
bt
For some reason, the whole "let's take an airplane from previous era, and thoroughly modernize it, thus saving money" reminds of a beautiful thread, on this very forum, about Nimrod re-winging fiasco.
About a massive effort to fully create a digital master drawing set for a single airframe, only to realize that other airframes are not really identical to it...
About a cost overrun so massive, as to eventually abandoning the entire program...
Yes. probably these days. compatibility would win both on cost on and on performance.
Just buying feedstock airframes cheaply would not make the program cheaper.
Compatible airframes, as fully known quantities, would be way better.
and 747-8 is inherently compatible.
When BAe became BAE Systems, they got rid of a lot of those pesky staff, with long experience, likely on better pay and pensions, who would have warned of this. Some of them likely built the original frames.
Plus the Treasury, in 1996 BAe offered both the rebuild or all new, the Treasury were loath enough to fund a new ASW aircraft, hadn't the MoD realised the Cold War was over? So they split the difference, 're-build'
must be cheaper than all new, right?
I was in BA Concorde tech at the time, they had differences between each frame, beyond G-BOAF the last ever built, being a tonne lighter than G-BOAC, though when the Air Intake Control Units needed either replacing or rebuilding/replicate the originals, (quickly settling on the latter as for all the advantages of 25 year newer computer technology, neither operator could spare an aircraft for the long process of testing to get regulatory approval for an all new control system).
The originals had been built by HSGW, the guided weapon division of Hawker, so now BAE had to ask people back from retirement to fix problems they couldn't, same happened with the replacement rudders too, they messed up on the sealant so the new ones lasted for a fraction of the time the originals had.
Gone massively off topic there, sorry!
I don't think though what I outlined above will remotely happen with the E-4B replacement, for one our 'airline operation within an airline' was hardly compatible with the sheer resources of the DoD and Boeing. The latter have blotted their copybook a lot in recent times, such a high profile and high scrutiny program like this might even restore some better practice all around?
I am still pissed BAE screwed up the MRA.4A though, should have brought 'em all new.