If memory serves, the Skymasters were ferried to Vietnam on both engines for virtually the entire trip. There was a wonderful, long article about the aircraft, with a detailed description of the ferrying in the SuperSkyRocket web site, but that site has now gone. The link used to be
http://www.superskyrocket.com/pages/...istory_1_1.htm. If anyone copied the article, please let me know so we can post it here.
The following is my recollection from that article. I believe it to be substantially correct.
The sole aircraft that ditched did so because one of the engines went out, and the extra fuel it was carrying was so great that it could not maintain altitude on a single engine. The C-130 shepherding the squadron arranged for SAR and the ditching pilot was rescued.
Why that engine quit is an interesting story.
For the long flight with new (read: barely broken-in) engines, all aircraft were equipped with a simple hand pump contraption that allowed the pilot to add a specified amount of oil to both engines at specified times during the flight. The amount of oil and frequency of refill had been calculated based on oil consumption tests performed on various new or nearly new engines. It was fine for all of the engines on all of the ferried Skymasters, except for one engine. That engine, by pure chance, had a perfect set of tolerances and had essentially zero oil consumption. The added oil kept rising on the crankcase until it flooded the spark plugs and shut the engine.
Ernie