Ductless Turbofan

[GregGleason]

I thought this looked a bit interesting, but perhaps a bit unnerving to watch as it spools up.

https://www.gizmodo.com.au/2014/01/...oks-broken-but-it-may-revolutionize-aviation/



Greg

 

[fyrwrxz]

Greg- I remember seeing something similar back in the late 80's at some NASA research facility (Dryden?) Didn't get to stick around to see it run, but the thought of those Ginzu knives at speed gives me the willies. I'll take a Kevlar containment shroud any day, thanks!

 

[GregGleason]

Mr Wrxz, do either of these look familiar?



[YOUTUBE]c0Icfopt8Yw[/YOUTUBE]

Greg

 

[PropellantHead]

Yep, those were plastered all over the covers of magazines like Popular Mechanics / Popular Science as well as most every Airliner & aviation related journal back in the day. They realistically can deliver 30% fuel savings over "normal" jet engines but the problem with these propfans is that they were VERY noisy and there was no way they could meet the noise restrictions at most airports. Once that was realized, the propfan pretty much just went away. It's starting to make a comeback, however, as new developments and technologies are promising that new generations of propfans could meet the noise restrictions by 2030.

 

[ThirstyBarbarian]

I thought this looked a bit interesting, but perhaps a bit unnerving to watch as it spools up.

https://www.gizmodo.com.au/2014/01/...oks-broken-but-it-may-revolutionize-aviation/

View attachment 169726

Greg

Are you sure that is not a robotic squid?

 

[BABAR]

Looks like it could make a great smoothie, or a frozen daiquari

 

[fyrwrxz]

Mr Wrxz, do either of these look familiar?

View attachment 169733

[YOUTUBE]c0Icfopt8Yw[/YOUTUBE]

Greg

Yes-I dimly (hah-my normal state of being now!) remember it was supposed to be for Lear-type all composite private jet.

 

[fyrwrxz]

Looks like it could make a great smoothie, or a frozen daiquari

No worries about bird strikes/ingestion-instant Seagull Frappe' !

 

[hornet driver]

Of interest, The airlines poo-pooed the idea even though they promised 50-60% reduction in fuel consumption. MD/ Boeing was so sold on the idea that all MD-88/90 aircraft were built to accept these powerplants and could be retrofitted at a later date if wanted with little modification

 

[Zonie]

I remember these

Hence the C9 / MD8 with the UDF Mounted in the photo...

Not much different from a turboprop at any rate except perhaps the blade pitch looks fixed and IIRC they turn at turbofan speeds which is much faster

Of interest, The airlines poo-pooed the idea even though they promised 50-60% reduction in fuel consumption. MD/ Boeing was so sold on the idea that all MD-88/90 aircraft were built to accept these powerplants and could be retrofitted at a later date if wanted with little modification

 

[luke strawwalker]

I've seen pics of something similar to this installed on the Tomahawk missile. Would have used the same kind of contrarotating fans as shown in the article... the fans would have been directly in front of the rear fins...

Neat stuff...

Later! OL JR

 

[fyrwrxz]

Cool! I was on the team that decanted* the first GLCM motor. It was so tiny compared to the Atlas engines-we all thought 'go-cart'! That propfan may have posed insurmountable problems in the GLCM and SLCM models*. I was totally unaware that was ever considered.
(*) They come in a nitrogen pressurized canister.
(**) GLCM=ground launched cruise missile, SLCM=submarine launched cruise missiles. Boeing was awarded the ALCM (Air-launched cruise missile) due to National Security issues (decentralization).