The KC-46 program has not gone swimmingly. I'm curious how they think they're going to get a demonstrator flying in 5 years when they can't get a tanker that's based on an existing production airframe flying on schedule.
That's what happens when protectionism gets involved. The Boeing design (based on an existing plane, but with some new systems and a combination of components from different generations of 767s) was chosen over the proven, already in production A330 MRTT. Delays and cost overruns are to be expected.
Same thing with ships, in the end US Navy had to accept it's not that special and it ended up ordering an RFP based on existing off the shelf designs (with the Franco-Italian FREMM winning).
I wouldn't be surprised if its got a heavy use of composites as well, in order to reduce he number of total parts. For the ACCA, they had 300 structural parts vs 3,000 metallic and 4,000 mechanical fasteners vs 40,000 otherwise.
https://www.lockheedmartin.com/en-us/news/features/history/a...
For that level of effort, five years probably isn’t impossible, but it’s definitely unlikely.
Did it really?
According to this fairly recent GAO report[1], the Poseidon's mission capable rates have missed their minimum 80% target since 2015, trending downwards (Table 1); only the first 2 out of 7 years were satisfactory (Figure 7), and yet those years' metrics were based on Increment 1 low-rate initial production lot that were "not effective for the intelligence, surveillance and reconnaissance mission" and "not effective for wide area anti-submarine search" that they were originally intended for[2].
Even in early years when maintenance staff was stacked balls deep at well over 100% (Figure 5), persistent supply issues plagued the platform, trending upwards (Table 5). To be sure, this outcome was entirely predictable; e.g. picking on Northrop Grumman's Electronic Support Measures system[3] that the Bloomberg article calls out as just one example: if you knew how the sausage was made, then this 2006 GAO report[4] which highlights certain risks "of particular concern" surrounding ALQ-218 development is all of sudden prescient in that it took so long to get the underlying system to acceptable maturity on the Growler that it became a very real commercial obsolescence sustainment risk by the time the Poseidon's full-rate production decision was made!
[1] https://www.gao.gov/products/gao-22-104533
[3] https://news.northropgrumman.com/news/releases/northrop-grum...
Except that Boeing has already one it:
* https://en.wikipedia.org/wiki/Boeing_KC-767
And Airbus (who originally won) didn't seem to have a problem:
It seem it is possible to write specifications that cannot easily be met by incremental change, and that might be one reason why the British aircraft industry ended up creating technically competent aircraft with little sales potential.
The 737 was harder than a new design - that’s why it went wrong.
Everything stems from Boeing taking this deal. Within the constraints of the 737 type certification: more efficient engines are larger, larger engines must move forward, forward engines change flight characteristics, flight characteristics must be augmented to maintain certification.
So you are correct that Boeing had choices other than "crashy 737", but that choice was between throwing billions away to Airbus and the crashy 737.
in other words, Boeing's thesis was, because we (heavily) modified the 737, it's the same basic plane. The FAA accepted this argument. The FAA would never have accepted the argument that a totally new design was "actually a 737 ".
The 747 MAX that killed 346 people in two separate accidents and was grounded for nearly two years and cost Boeing 10's of billions of dollars in fines, cancelled orders, etc.?
It is perhaps not the best example of modifications to an existing design.
And I don't even blame the Air Force for deliberately underestimating. They have a legitimate need for this aircraft and the existing fleet has been worked to death.
Who knows? Maybe a tanker could happen that fast since it won't integrate a bunch of weapons. They're only promising a full scale test by 2027.
[1] https://www.thedrive.com/the-war-zone/next-gen-air-dominance...
https://www.thedrive.com/the-war-zone/40821/kc-46as-long-tro...