>>I think, Greg, that the funnels would have been shorter like those on MV Britannic<<
I'd be very skeptical of that. The M/V Britannic was a diesel powered ship. The Oceanic was a steamship. The reason steamships tended to have taller funnels was because of the greater volumns of smoke and soot produced by the boilers. Higher funnels helped to keep all this muck from settling on the decks and the passengers.
Actually, the design of the machinery plant for Oceanic III was heading towards being a diesel-electric plant -- something like 47 or 48 diesel/alternator units, with the power being split amongst four shafts being driven by electric motors. If this ship had been built, then just like the Britannic III and Georgic II, the only steam generated on board would have been from exhaust waste heat boilers, used to produce steam for heating, domestic fresh water distillation and hotel services. (Steam from waste heat can also be used to run turbo generators for ship's lighting and ventilation while at sea; then, in port, the load is switched over to diesel generators.) Remarkably forward-thinking, this machinery plant; in a way, the marine engineers at H&W, who were pioneers in the application of diesel technology to ship propulsion, were predicting the main machinery of passenger ships some 65 to 70 years in the future.
Update: Per both The Shipbuilder and Dr. Griffiths' Power of the Great Liners, the total number of six-cylinder medium speed diesel alternator sets was to have been 47.
A fall-back option that was under consideration was a turbo-electric plant similar to what was eventual used in the Normandie; had this been the option chosen, then I'm sure that the funnel height would have been raised in keeping with steamship practice, more like what was done on the Queen Mary. Somehow, I doubt that H&W would have stepped into the same trap that snared the builders of the Bremen and Europa!
Anyway. Either way, I very much like the drawing, and whether it would've been historically accurate or not, I think the raised funnels are far nicer looking than the squat things of the motorship era.
"...Also interesting. I don't suppose any sort of final decision was ever made was it? Seems to me the stillbirth of the whole project would have rendered any such deliberations moot..."
No, no final decisions were made that I'm aware of, though the diesel option seems to have been the leading horse in that contest, at least at the point in time the last short article made it's appearance in The Shipbuilder at the time the keel was laid. Interestingly, though not mentioned anywhere, the early model shown on page 258 of Shipbuilders to the World hints at even a third, earlier consideration, since this model depicts a Queen Mary-ish hull with a triple screw arrangement. Seeing this leads me to wonder if the original proposal, which dated to 1925 or earlier, might not have been using combination machinery per the Olympic-class in the original proposal.
>>I think the raised funnels are far nicer looking than the squat things of the motorship era.<<
I agree with that. The thing is with diesels, there just wouldn't have been a need to raise the funnels all that high for any reason beyond the aesthetic. Since excessively high funnels can contribute to topweight problems, shipbuilders have an obvious incentive to avoid it if possible.
>>since this model depicts a Queen Mary-ish hull with a triple screw arrangement. Seeing this leads me to wonder if the original proposal, which dated to 1925 or earlier, might not have been using combination machinery per the Olympic-class in the original proposal.<<
That's intriging. I'm wondering if it was simply ruled out as impractical for a ship of that size or if the alternatives were seen as being better.