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>technology well developed during the 80s
>proof of concepts are a great success
>planned for production in early 90s
>all ideas scrapped because the price of oil tanked
>vaporware
Why haven’t we seen the dawn of the age of prop fan powered aircraft yet?
>>
>>1684234
>Why haven’t we seen the dawn of the age of prop fan powered aircraft yet?
Because they sound like a circular saw on steroids.
>>
>Please use our loud as shit engines
No thanks
>>
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>>1684262
>>1684281
Because 80s turbofans were the pinnacle of silence. Fuel consumption could be halved but because prototypes from 40 years ago were too loud all development has ceased? Propfan designs from 10 years ago already met Stage 5 requirements, and that's not even accounting for additional sound shielding.
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>>1684285
>Because 80s turbofans were the pinnacle of silence.
That's exactly the point. We don't want to go back to loud airliner engines, we want quieter engines
>>
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>>1684287
My point is in the last 40 years we've quieted turbofans down a ton, given the same development time I'm sure a lot of progress could have been made quieting propfans. Again, 10 years ago the noise problem was already a non-issue, and Safran maintains they have a design that's as quiet as the CFM LEAP.
>>
>>1684290
No one wants to design new airframes so much that 737 MAX happened. Propfans are not offering enough to justify re-training and re-tooling entire fleets.
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>>1684291
>so much that 737 MAX happened
And look how well that's worked out so far. The industry is changing, we can't keep retooling designs from the 60s forever.
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>>1684234
Because turbofans got much more efficient over time and much quieter.
>>
>>1684292
That doesn't mean you need propfans either.
>>
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>>1684234
Propfan has just been resurrected by CFM.

https://www.cfmaeroengines.com/press-articles/ge-aviation-and-safran-launch-advanced-technology-demonstration-program-for-sustainable-engines-extend-cfm-partnership-to2050/
>>
>>1684291
Imagine if instead Boeing unshrunk the 717 and bolted a couple propfans to the back. They tested these things on md80s it wouldn’t have even been that difficult
>>
>>1684290
>given the same development time I'm sure a lot of progress could have been made quieting propfans.
Great we just need to wait a few decades to have airliners that are as quiet as they are now.

If this was as great of an idea as you think it is, we'd have already adopted them.
>>
>>1684331
>airliners that are as quiet as they are now
That run on half the fuel. What I was suggesting is had people like GE not pulled all their engineers off propfan designs we’d have quieter engines today.
>>
>>1684336
If propfans cut fuel consumption by 50% or close to it versus turbofans, pretty much every aircraft would be using them today
>>
>>1684345
The real problem with prop fans is that they require higher mounted engines, which modern aircraft can't easily accommodate (see 737 max). In the future most aircraft will have 2 enormous turbofans bolted onto stubby little wings on a choad fuselage. The era of aesthetic innovation is over
>>
>>1684374
>>1684345
that and every marketer knows consumers dislike propellers and avoid them if they can. in the private jet market buyers will prefer the jet with higher fuel consumption and cost than a turboprop, even if they have similar performance (like a piaggio avanti)
>>
>>1684385
>that and every marketer knows consumers dislike propellers
Really doesn't matter, if the fuel savings were as substantial as claimed itt, every airline would demand them and every manufacturer would be offering a/c with them
>>
>>1684424
the atr and the dash 8 are ubiquitous yet despite being substantially more economical are replaced by jets whenever runways become long enough to accommodate them.

http://www.spsairbuz.com/story/?id=417

this at least shows how fuel economy and speed balance out tough, so it's not that linear of a relationship.
>>
>>1684449
>the atr and the dash 8 are ubiquitous
I wouldn't go that far
>>
Ducted turbofans made it obsolete
>>
Propfan go BBBBBRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRR
>>
>>1684298
I really hope someone has the balls to design something truly new. Passenger jets have looked more or less the same for 50 years at this point.
>>
>>1684499
Same as bicycles, they've pretty much reached the optimal configuration for a given set of parameters.
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>>1684510
Yeah but unlike bicycles the pinnacle hasn't actually been reached yet. Try designing a new bicycle nowadays and you'd just look like a tryhard faggot taking three steps backwards for the sake of it.
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>>1684385
Yeah, that's why the PC-12 isn't popular at all.
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>>1684474
>RRR
ArrgH?
>>
>>1684525
pc-12 main selling point is being able to operate on short, unpaved runways, which jets at that size would be unable to do.

>>1684510
you mean their design has been frozen by ucl which doesn't allow any other kinds of bicycle's to compete. everybody knows recumbents are faster on tarmac, and for offroad i suspect it could be improved but it seems optimal for now.





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