It’s not just money that made it possible…the 135s could be done in large part because they were not (and never would be) commercially operated.
The military has a lot more leeway in modifying its aircraft than an airline would.

I don’t know about that.
One thing that did make the 135 program viable was that there were hundreds of them to be modified. Boeing did build a new 707 with CFM-56’s but it did not attract any orders. The one “new build” pure 707 it did do ended up as a presidential aircraft somewere.

Rgds Cking

I THINK they were RR Tay’s.
Dee Howard also re fitted a BAC 1-11 with Tay’s. It was at Farnborough for the show one year. I seem to remember that BAe, who held the design authority refused to co operate with the certification process so the project was stopped. BAe were building the 146 at the time and the re engined 1-11 was seen as a competitor. Personaly both aircraft were awful in their own way and I’m glad their both out of my life!

Rgds Cking

It makes a mess of the birds too:D:D
Seriously, it always annoys me that once an airline has a serious incident every minor incident for about a month after gets headline reports.
“Ash tray full on Qantas aircraft, stocks fall”
“Qantas aircraft delayed by fog, Nothing to do with our maintenance, say management”

Rgds Cking

Or was the first thing out of their mouths “It wasn’t anything to do with our maintenance”

Rgds Cking

Has anyone EVER changed engine makes on an existing operational jet?

I’ve never heard of it happening outside of tests.
I’m sure in addition to the engineering issues, there would be a mountain of paperwork as wekk regarding certification.

You are going to kick yourself:o
Some 707/KC-135’s and DC-8’s changed to the CFM-56. I don’t think one entry in the tech log would cover it either:D

Rgds Cking

Hear are some pictures of the damage to the wing of the aircraft

http://blogs.crikey.com.au/planetalking/2010/11/17/the-anatomy-of-the-airbus-a380-qf32-near-disaster/

There is going to be some serious overtime for the Airbus repair gang on this one!!

Rgds Cking

Still much easier that getting permission to ferry the plane with one engine inoperable. I’m sure the red tape for such a manoeuvre would be 4 foot thick.

No not realy. Obviously it requires a few extra tech log entries and a management crew to fly it back but it is now the standard way to recover a quad and tri jet.
Engineeringly you have to boroscope the other engines and make sure they can reach max power (Some times done by the ferry crew at the end of the runway).Then you remove the fan blades and put a fairing over the core intake of the duff engine.

Rgds Cking