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So those 4360's where drinking what? 150 gallons each per hour if that? And the jets about a gallon per minute per engine that is 3600 per hour each. Maybe they weren't drinking quite that much and maybe more like 1800 per engine per hour, that still makes that 1.5 extra hour nothing. The catch is with a recip that uses jet fuel and an efficient airframe that comes close to 737 speeds, why not? The recip will always be way better at fuel economy than a turbine.
I would like to see fuel consumption numbers with those 30K plus HP figures. Also remember at cruise the power levels are backed off, as well as the speed. Also comparing a modern swept wing to old school prop airframes is not a fair comparison. There is an industrial engine that is at the 50% efficiency mark it is a diesel recip. I have seen chatter on some sites about electric motor power for aircraft, that is where an extremely efficient recip would shine as competition. When it comes to comparing maintenance of an old recip to a modern jet, where is the fairness of that? We are talking engines built 60 to 70 years ago against the latest and greatest. The parts for a recip will always be less costly than a jet / turbine, the manufacturing techniques as well as the exotic materials needed for turbines will always keep the costs up high. Turbines are sensitive to dust etc. and volcanic ash, birds and anything else that they should not be ingesting. A recip due to the lower air demand can be equipped with inlet filters to keep the bad stuff out.
Turbines are gas guzzlers and that won't change.
Those engines are low-speed diesels with bores of 500 mm and strokes up to 3 meters.
I would like to see fuel consumption numbers with those 30K plus HP figures.
Also remember at cruise the power levels are backed off, as well as the speed.
Also comparing a modern swept wing to old school prop airframes is not a fair comparison.
I have seen chatter on some sites about electric motor power for aircraft, that is where an extremely efficient recip would shine as competition.
When it comes to comparing maintenance of an old recip to a modern jet, where is the fairness of that? We are talking engines built 60 to 70 years ago against the latest and greatest.
The parts for a recip will always be less costly than a jet / turbine, the manufacturing techniques as well as the exotic materials needed for turbines will always keep the costs up high.
Turbines are sensitive to dust etc. and volcanic ash, birds and anything else that they should not be ingesting. A recip due to the lower air demand can be equipped with inlet filters to keep the bad stuff out.
Turbines are gas guzzlers and that won't change.
They would probably be diesels, so no spark plugs.
assuming reciprocating engine propellers show the same fall off in efficiency as turbo-prop propellers we can see that any reciprocating engine has some serious difficulty over 450-500mph and once you get to 550mph the efficiency of the propeller is pretty much in the toilet while the jets were coming into their own.
Most jet airliners cruise 30,000ft-40,000ft. Not the greatest place for prop efficiency.
Sorry but there is a small lack of knowledge of the state of the art diesels here. I'm not talking about a huge 3000 ton sulzer. The engine is from Fairbanks Morse it is an opposed 2 stroke, that boasts 50% efficiency it is light weight in comparison to the ultra large engines. There is no reason the technology can not be sized down and even better efficiency numbers could be attained, the use of power recovery techniques could help bring that number higher, amongst a few other additions. Diesels power to weight, you act like there are no diesels used in aircraft or ever has been used. Just do a little study on the topic. I also liked the recips wear faster, well it depends on what a turbine ingests how long they last, give them a nice sand storm or dirt / rocks on the runway, and a wrench or two. Then you got a multi million dollar pile of scrap.
Many turbines since the late 50s and 60s using a pressure ratio (think compression ratio) of over 10 to 1 (some are around 15 to 1) so their thermal efficiency is actually pretty good.