Arthur_Foyt
Isn’t it kinda early for April first shenanigans?
Isn’t it kinda early for April first shenanigans?
Not to worry, this idea will go nowhere in the US. Open rotor engine airliners were already tried in the US in the 1990’s, and the airlines said no thanks. Same reason the Q400 and the Saab 2000 went nowhere, American airline passengers will not ride on anything with a prop. And voters will not tolerate an airplane that sounds different than a jet whether or not it is any louder or it makes noise limits. Ask any airport that has banned the Piaggio Avanti turboprop(Santa Monica, Ocean Reef).
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Are you sure? I thought that airline passengers go for low cost more than anything. Like in the car industry when everyone thought it had to be a 12mpg V8 or at least a big V6 in their truck, yet the 20mpg+ inline 4 turbos with better acceleration and less noise are quietly taking over.
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I’m sure Boeing is going to respond with the 737MAX 11, which will immediately be grounded because they installed the wings upside down or something.
Well they have adjourned sine die development of hydrogen, first flight of airline prototype was due 2030, so looking for something to put on their website full of computer simulations.
My guess is that if Safran does dust off the open rotor, it will appear with a chicken wire cage around the prop fans to slow them down when they break off.
Time to order some extra large popcorn bags.
It’s Deja Vu all over again … I recall these very loud experiments back in the late 1980s. And the same wild predictions of fuel savings. Fact is, more conventional turbofans have made huge advancements too since then. I’m guessing that CFM secure EU Green money to fund this work, at a healthy profit margin. Don’t expect to see one soon on a commercial aircraft.
The CFM spokesman did say that the re-engined A320 would “ float like a butterfly, sting like a bee” . 
I’ve been hearing this one since working on an acoustic model in college in 1982. I have to say that I’ll believe it when I see it. Acoustics, icing, blade retention, and blade off issues have thus far proven to be overwhelming.
Fortunately engineering isn’t governed by such thinking. So just because someone else couldn’t do it, a very long time ago, doesn’t mean it wasn’t a good idea that should be looked at again. Imagine if some fool had told Frank Whittle (and the others that were also working on successful designs) that the jet engine had already been tried, where would we be now. The main reason it could fail in the US is a mixture of isolationism and… oh yeah, that’s the main thing.
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Never said it couldn’t be done. I worked on the deicing system for what would have been the MD95, before the project was dropped due to no interest by the airlines. That plane became the 717 after the McDonnell Douglas/Boeing takeover/merger. Politics and passenger preference is what I was referring to. There have been no new prop driven pt 121 airliners designed since the 1990’s, again due to lack of interest by the pt 121 airlines. American passengers do not like and will avoid riding on any currently flown pt121 prop airliners. The only exception would be in Alaska, where there is not much in choices. Even the pt380 airlines that the pilot unions and Congress want to move to pt121 mostly use older regional jets, not props. Then there is the politics involved with noise restrictions. From what I understand noise restrictions in Europe and Canada are more restrictive than in the US. That is why I doubt this proposal by Airbus will get very far.
Ayup. 
How about a passenger-certified A400M - fuselage low to ground to aid servicing?
(Already carries passengers in military seating, I expect.)
Presumably this is for a rear mounted configuration, correct (a la MD-95)? Can’t imagine how this would pass certification muster from a safety perspective.
Uh, has it been tried outside of the US?
Weren’t their actual flight tests in the US of an airliner with one ‘propfan’ installed?
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Airbus does seem to go for shallow PR.
Must be pc for its owners.
The US tried it, the aircraft was at Farnborough one year. These engines aren’t vastly different from the A400M’s turboprops. The tech is sort of closing in on the propfan from both ends. Fans are getting fewer and bigger blades, turboprops are getting more fan like blades. Eventually they will meet in the middle.
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Chris H:
An apt observation, thanks.
The huge question is whether or not voters will wake up to the con job that humans are causing runaway warming of earth’s climate, which is not and cannot happen.
Accurate temperature measurements like weather balloons, satellite sensors, and tide gages show only slow warming since the end of the cool era that drove Viking farmers out of southwest Greenland. (The Medieval Warm Period was warmer than today climate was stable.)
The ‘saturation effect’ of overlap of spectra of carbon dioxide and dihydrogen monoxide limits rise to a small amount most of which has already been realized. (Changes in water vapour show there is not a positive feedback mechanism.)
Whereas the well known effect of orbit changes - ‘Milankovich Cycles’ - varies climate.
So the only benefit is lower operating cost but at what price in aircraft capital cost and safety?
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Whatever you say. LOL! But for anyone who believes this, take a look at the real temperature records. You believe what you like, it won’t make a difference. Too late for places like Miami that are already seeing ‘nuisance flooding’. Because legislating against calling a spade a spade makes a difference. See all the red, that’s industrialization, not Viking farmers.
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Chris:
‘Real’ by whose claim?
Catastrophists are regularly caught lying - the leak of emails from the CRU illustrated that (‘scientists’ conspiring to block skeptics from publishing in journals), fudging temperature databases that do not properly account for the urban heat effect, falsely claiming increase in severe weather (even IPCC says there is no indication of that), …
And failing to do homework: land rises and sinks - US east coast is sinking, Miami has the weight of tall buildings and ground of questionable stability, but some locations on the midwetcoast are rising (study plate tectonics).
As for Wikipedia, it’s well known that catastrophists edit pages to push their agenda - Wikipedia lacks tough supervision (though one catastrophist was banned for repeated push to bias pages).
(Your comment about industrialization does not make sense, but hey! neither does your catastrophism. (Or are you stumblingly avoiding evidence that the MWP was warmer than today?)
Actually, many people are buying big pickemups.
(In some cases out of disgust with EV charging problems they encountered.)
Variety is good, to suit need and budget.
(Need being no family thus small, or maintaining house, or sometimes bully look with black.)
Chris H:
BTW, averaging over the vast area of oceans is questionable because of inconsistency of observations. But satellite sensors which do cover oceans.
(Its been shown that temperatures measured in ship intake of water for cooling is not accurate, thus older records are not useable.)
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Lots of irrelevant straw men in that triggered outburst. None of that BS and attempts to trigger disdain make any difference. Believe what you like, go and buy a home in Miami. The idea that sea level rise, on both coasts, is due to the land sinking is laughable. There’s some loss around places like the Sacramento river delta and the Mississippi river delta and similar places. So there’s your straw man. But that doesn’t explain coastal flooding in the Granite State. And in any case, the satellite measurements show the sea level rise. In the time since I started visiting the coast, sea level has risen 4 inches. In the time since I moved to the coast it has risen 3 inches. Satellites have been measuring land levels to millimeter accuracy for most of that time. The land isn’t going anywhere. You are the sort that believed the tobacco companies about the healthy effects of smoking. Yes, that’s an ad hominem, but I don’t care. I don’t think I can do anything for your ‘beliefs’.
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Chris H:
Thankyou for confirming you emotional method of knowledge - ad hominem attack using completely irrelevant point and evasion of my points with silliness like 'straw man". I hope you don’t fly an airplane.
FTR, sea level may be rising but how fast? It can be expected to as climate warms in the current Milankovitch Cycle, it will cool again.
Open rotor design has some flaws. One big one is rotor failure due to fod, bird strikes etc. With newer, current ducted designs, the powerplants are becoming more efficient with less exposure for blade damage and containment. I agree with other posts here; this won’t work out very well.
A shorter term variation is earth’s tilt axis varies, which creates greater difference between seasonal temperatures.
Note low temperatures kill many more people than high temperatures.
And note that CO2 is our food, via plants (and animal converters), increasing CO2 increases plant growth.
As for orbital variations, gravitational attraction from other planets varies because each planet has a different period, that was known centuries ago. (David Harriman mentions that in his book ‘The Logical Leap’.)