PW-Allison 578-DX Propfan: A Technical Description

[Tadesan]

Sigh. This is mana for engineers.
Thank you so much for sharing such wonderful information. It's wonderful to hear about human accomplishments in the language that they are achieved.

Engineering is an amazing discipline that challenges the world with truth.

People should talk about and share engineering so much more.

What a wonderful video.

[andyharman]

John Spratt, Ron Riffel, and Al Novick are names I remember from my time as an engineering co-op at Allison from 1980-85. I had work assignments in advanced gas turbine test and advanced military engine groups during that time. Those guys were so far above me, it's embarrassing to mention, but what was a 19-21 year-old supposed to know anyway? I mostly kept my mouth shut and my eyes open. But it was a great first exposure to major engineering projects for a kid just out of high school. I worked on the T56-Series IV large-scale compressor test, the AGT-100 compressor and regenerator test rigs, and proposals for the ATEGG core engine for the USAF ATF program.

[JAMESWUERTELE]

These are the technical videos I crave!! More!

[dmacpher]

Don’t know how I ended up here, but this is amazing work

[tannerholmes]

This video is cool af! A treasure trove of information and insight! Thx!

[jiyushugi]

For those new to the AEHS, they also produce an excellent magazine covering all of the significant aircraft engines. If you ever wondered how torsional vibration was measured during development of the early radials, or how the engine failure problems of the P-38 were solved, this is the magazine for you!

[brow]

This is one of the most interesting videos I've come across on YouTube. It feels impossible to get detailed analysis and information about anything anymore, so this is just phenomenal! Great Job!

[ethanspaziani]

And they are still circling back to these designs even today because they are just better

[wbwarren]

Great video! Thank you very much! Of particular interest was the cooperation of so many different manufacturers in the development of this engine. The complexity of this effort is tremendous and highly encouraging. Until I saw this video, I thought rocket science was rocket science but now I realize that Ted engine development is really the real rocket science.

[jorgel]

What a wonderful video! Thank you so much for your excellent presentation on the topic.

[nadahere]

Thanks for the wonderful presentation. Contra-propulsors are of interest to our development of the low cost, personal, door-to-door PersonalJet VTOL system

[christophermaglio]

Thank you for putting together a great video. The detail level is fantastic and the technical accuracy is excellent. I had no idea how inefficient at takeoff these propfans are - 2 lb per Hp is horrific.

[basilb]

Excellent! You cannot get this detailed information anywhere else. I was waiting for this since your presentation of the GE36.

[jeylful]

Wonderful video! Incredible that they kept the exhaust before the propellers, you would think that configuration creates a lot of headaches (some mentioned in the video like the blades exposed to alternating high and freezing temperatures). Thank you for your presentation I really enjoyed it even when my work is not related to aircrafts.

[machpodfan]

Fascinating post, much appreciated. From what I've seen, at least in the proposed commercial applications, noise was a significant issue. Amusingly, the acoustic signature of most of the propfans to fly was similar to piston-engined aircraft. The Russian AN-70, for example, sounded for all the world like a Briggs and Stratton-engined lawnmower at full throttle.

[shcchristensen]

Great deep dive Tom, certainly a missed opportunity that’s coming back into vogue. Thanks-“Shooter” FDX

[greybuckleton]

I really enjoyed this. When I studied Basic gas turbines at university I was always fascinated by how these engines looked, and thought they had been discarded unfairly. Fuel is expensive again now, time to dust off the Propfan!

[ssnider]

Excellent! Answered many of my questions about this.

[davidreinhart]

I was looking forward to this since the GE36 video!

[BlitzvogelMobius]

I always wondered what kind of issues the exhaust caused on the front rotor of the 578-DX. Also surprised by the GE36 having superior TSFC and it's higher weight. Figured the gearbox in the 578 would've presented some efficiency advantages while adding much more weight compared to the GE36's direct system.