Originally Posted by
markinnorthtexa
I wonder what the reasons were that they did not start with a clean slate and a new design in the first place.
Because it would have cost something in the rough ballpark of $15-20 Billion MORE to do a clean slate design.
The tube and the wings, and most of the systems still work fine. So they spend the money on things which would increase efficiency by significant margins. Also some safety enhancements such as cockpit tech.
Originally Posted by
markinnorthtexa
If that was the safe bet, I wish they would have made that bet instead of the one they made. I also wonder how long it is safe to stick with a design.
If the design was safe to begin with, it will remain safe forever (unless you change things carelessly, as we have seen).
The only reason to do a clean sheet design is to take advantage of NEW technologies which provide one or more of several advantages...
Lower operating cost (fuel burn, structural weight, mx, crew training, etc).
Lower manufacturing cost.
Enhanced safety, although most customers mostly just want enough safety to comply with certification standards, plus maybe a few operator-specific optionals such as HUD.
Originally Posted by
markinnorthtexa
I have read where we still have the Boeing B-52 airplanes flown by our military and how they still have to use shot gun shells for quick starts when they want to get going fast.
The B-52 got a very large lease on life... it will likely fly for about 100 years now. But that's just DoD being financially smart.
The B-52 was very obsolete and not survivable dropping bombs in a contested environment (ie opponent is more capable than low-tech insurgents). But new weapons, targeting, and guidance technology now enables the B-52 to launch standoff weapons from a very great distance. Since it works, is sturdy and reliable, and can carry a huuuuge amount of ordinance compared to other platforms, why not keep it around for standoff work? It can also still safely drop (guided) iron bombs from the stratosphere if we have air superiority.
Originally Posted by
markinnorthtexa
It sure seems like our aviation industry is not really leading the world in some respects. I am learning how there used to be more airplane manufacturers here in the US. Perhaps the competition way back when resulted in better and safer designs. Thank you for all of the helpful information and replies.
The designs were most definitely NOT safer back then, LOL. When I was a kid there were a lot fewer airliners, but it was a rare year when several didn't crash. Today's enhanced safety levels derived mostly from technology and increased regulatory sophistication (with some gains on the operational, procedural end, ex CRM).
We are not leading the world quite the way we did back in the day. One of the factors is that government spends less on raw R&D, leaving that more up to industry. Companies are now more responsive to IMMEDIATE shareholder concerns and short-term interests, and are loath to blow money on R&D which does not have a clear ROI, within a relatively short time frame. The aviation world is aware of this, and there is a movement to push for more cutting edge R&D (gov and/or industry funded).
In fact this plays into why both Boeing and Airbus did NOT do clean-sheet new narrowbodies last time around...
The are several key technologies being evaluated by government initiatives (on both sides of the Atlantic) which will likely provide very major (revolutionary) improvements in efficiency and emissions (and maybe mfg cost too). The problem is they are not quite ready for production AND they involve radical changes to airframe and engine design, and possibly engine location.
Since that new tech may be right around the corner, if either mfg blew $20-30B on a new "traditional" airframe, the other might be able to wait five years, and then deploy the new tech, with vastly improved efficiency (like over 50%), utterly blowing their competitor out of the water.
If airline manufacturers are going to spend tens of billions on a new plane, they have to be certain they can sell a lot of them for a long time. The nature of the new tech is that it will require clean-sheet designs, ie cannot be retrofitted.