Ever wonder about the Wright R-3350 TC18 Power Recovery Turbine?

[Tom Fey]

Thirty-two minutes of PRT trivia:
View: https://youtu.be/1j9164wb6TE

 

[MIflyer]

Back in 2001 I saw those on a Super Connie they had at Camarillo Airport. Note that it had three turbines.

I saw a video in which a former Lufthansa pilot described the Super Connie as "A three engined airplane with four engines" which gives you some indication of the engine's reliability. A friend of mine served on EC-121 crews that flew out of McDill AFB and did radar surveillance to see if there was traffic between Cuba and Nicaragua. They would shut down the two outer engines to extend their mission time.

 

[fannum]

A friend of mine served on EC-121 crews that flew out of McDill AFB and did radar surveillance to see if there was traffic between Cuba and Nicaragua. They would shut down the two outer engines to extend their mission time.

A common practice on Nam EW and WV weather Connies. Still used today for long patrol P-3s and EW C-130s.

Addenda: Just checked with a friend who was an E-2 driver to make sure his tales were not sea stories.
He swore on the Bluejacket's Manual that when he was in S2Fs doing long anti-sub, and later when on station in E-2s, they'd shut down and feather the port engine to extend duration, and Grumman had built in plenty of trim to make it a no-sweat procedure.
Yes, boys and girls, Official Gouge: this ain't no sh@t!!!

 

[SaparotRob]

GO GRUMMAN!
Blue paint for everyone.

 

[fannum]

btw - Burt and Dick Rutan's orbital Voyager only used the larger forward engine for the takeoff and first third of the flight, shutting it down for the efficiency needed to complete circling the globe.

 

[MIflyer]

Bagged Atlantis Models Reissues of the old Aurora 1/54 S2F still available from Atlantis-Models.com for $9.99 plus shipping.

 

[Simon Thomas]

Thanks Tom. That was a good video.
In case that user didn't message, attached is the document they mentioned.

Do you have any information that can quantify the reliability of the TC18? There are numerous references to the "Parts Recovery Turbine" and the DC-7 being a "three engined plane with four blade propellers" but I suspect that does not tell the whole story.
Quite a few engines are dismissed as being terribly unreliable, but it seems that (a) adverse reports are taken as being the norm rather than isolated incidents and (b) the unreliability of the first versions is taken as typical for the later versions which could be far more reliable.
The other variable is the care of the pilot. TSIO-520s and 540s / GSO-480s etc can last only a few hundred hours with a ham fisted pilot but a careful pilot can get them to TBO and beyond with no issues.

 

[Tom Fey]

Thanks Tom. That was a good video.
In case that user didn't message, attached is the document they mentioned.

Do you have any information that can quantify the reliability of the TC18? There are numerous references to the "Parts Recovery Turbine" and the DC-7 being a "three engined plane with four blade propellers" but I suspect that does not tell the whole story.
Quite a few engines are dismissed as being terribly unreliable, but it seems that (a) adverse reports are taken as being the norm rather than isolated incidents and (b) the unreliability of the first versions is taken as typical for the later versions which could be far more reliable.
The other variable is the care of the pilot. TSIO-520s and 540s / GSO-480s etc can last only a few hundred hours with a ham fisted pilot but a careful pilot can get them to TBO and beyond with no issues.

Thanks for your comments. The detailed history of the TC18 in commercial service is complicated, bumpy, inconsistent across operators, and not easily packaged into the current video. The early versions, particularly the "DA" series of the TC18 had numerous serviceability problems, many, but not all, were related to the PRT system. The later versions, the "EA" series, was greatly improved and when operated by the book served well for decades in the EC-121 and P2V aircraft. TC18's in the commercial world were pushed quite hard in a vain effort to "keep up" with the new turbojet aircraft. The attached document is a point-in-time summary of United's experience with the TC18.

 

[fannum]

A lot of the failure of the Wright Duplex Cyclones was due to pressure of airline bragging rights.

In 1946, these WWII developed airliners were finally able to fly non-stop with a full load from LA to NYC, and a speed race developed. That had always been a measure of airline superiority: A 1929 TWA Ford Trimotor could make the trip in just less than 20 hours; the DC3 reduced that with a three stop, 18-hour speed run; the speedy post war Douglas and Lockheeds managed 8-hour hops, and the marketing departments took over.

Superlatives abounded, with ads sprinkled with Sky Tourist, Mercury Service, Jetstream, Siesta Sleeper, Flagship, Monarch, Super G. The public got abundant images of sleek aluminum steeds, elegantly sexy stews and studly pilots, plus ads sprinkled with cameo celebrity testimonials.

Newspaper ads and articles were full of "new" records from airlines, inching under the 8-hour milestone, with PR blasts touting shortening travel by ten minutes at a time, which were rewarded with increased bookings for the speedier fleets. Once below 7 1/2 hours, engine improvements became less of a benefit, and cruise settings got pushed up and up. My airline pilot friends reported firewalling the throttles at the start of a LA takeoff run, only pulling back on the letdown into NY. Most engine failures happened when throttle settings were changed, especially rapidly, thus most occurred on departure or descent. A good flight engineer could make a big difference in engine life and failures.

It was a DC-7C vs Super Connie showdown, and I recall full page ads and headlines when the magic 7-hour run was exceeded. (Note that Douglas, Lockheed and Boeing all investigated turboprops for their airliners, but then their reliability was not up to their needs.)
The Last Gasp Airliner Race

Then it all changed. "On January 25, 1959, American pioneered transcontinental jet service between New York and Los Angeles." Its inaugural 707 Jetliner Flight 2 carried eight crew members and 112 passengers on its record-setting continental crossing it in four hours, three minutes.

 

[SaparotRob]

A lot of the failure of the Wright Duplex Cyclones was due to pressure of airline bragging rights.

In 1946, these WWII developed airliners were finally able to fly non-stop with a full load from LA to NYC, and a speed race developed. That had always been a measure of airline superiority: A 1929 TWA Ford Trimotor could make the trip in just less than 20 hours; the DC3 reduced that with a three stop, 18-hour speed run; the speedy post war Douglas and Lockheeds managed 8-hour hops, and the marketing departments took over.

Superlatives abounded, with ads sprinkled with Sky Tourist, Mercury Service, Jetstream, Siesta Sleeper, Flagship, Monarch, Super G. The public got abundant images of sleek aluminum steeds, elegantly sexy stews and studly pilots, plus ads sprinkled with cameo celebrity testimonials.
View attachment 814691
Newspaper ads and articles were full of "new" records from airlines, inching under the 8-hour milestone, with PR blasts touting shortening travel by ten minutes at a time, which were rewarded with increased bookings for the speedier fleets. Once below 7 1/2 hours, engine improvements became less of a benefit, and cruise settings got pushed up and up. My airline pilot friends reported firewalling the throttles at the start of a LA takeoff run, only pulling back on the letdown into NY. Most engine failures happened when throttle settings were changed, especially rapidly, thus most occurred on departure or descent. A good flight engineer could make a big difference in engine life and failures.

It was a DC-7C vs Super Connie showdown, and I recall full page ads and headlines when the magic 7-hour run was exceeded. (Note that Douglas, Lockheed and Boeing all investigated turboprops for their airliners, but then their reliability was not up to their needs.)
The Last Gasp Airliner Race
View attachment 814689
View attachment 814690
Then it all changed. "On January 25, 1959, American pioneered transcontinental jet service between New York and Los Angeles." Its inaugural 707 Jetliner Flight 2 carried eight crew members and 112 passengers on its record-setting continental crossing it in four hours, three minutes.

 

[Snautzer01]

If a Connie would have been a woman she would have been named Marilyn.

It is the most beautiful piece of aluminum in the air. Ever.

 

[SaparotRob]

If a Connie would have been a woman she would have been named Marilyn.

It is the most beautiful piece of aluminum in the air. Ever.

Looking forward to the firestorm of replies to this!