Supercharging for economy?

[dcb]

That's a very impressive effort by Julian.

[Mustang Dave]

Originally Posted by Old Tele man

...how many TURBO-charged WWII fighter aircraft were there compared to SUPER-charged WWII fighter aircraft? Uh, none!

Uh, one comes to mind. The P-38 Lightning was turbocharged.

[user removed]

Originally Posted by Mustang Dave

Uh, one comes to mind. The P-38 Lightning was turbocharged.

Yep, Pop was going to ferry one from England to Paris and had a turbo fire and aborted.

Forgot that one, but I believe most of the radial engine planes were turbo charged.

regards
Mech

[gone-ot]

...after WWII, both (SC & TC) were used together, one example being the turbocompound Curtis-Wright R3350-42 engines, which had a single-stage, two-speed, supercharger and three 'Power Recovery Turbines" (PRTs). The PRTs extracted 500 HP from the exhaust gases from the 18 cylinders and put it back into the engine crankshaft, boosting total output power from 2,900 HP up to 3,400 HP per engine...plus delivering lowest fuel consumption per HP at lean cruise, only about 100 gallons/hr per engine.

[dcb]

IIRC, it wasn't long before they realized they didn't need the ICE in the middle.

[gone-ot]

Originally Posted by dcb

IIRC, it wasn't long before they realized they didn't need the ICE in the middle.

...LOL, "true" ie: SC-ICE-TC.

...however, just about any ICE aircraft engine gets BETTER fuel economy (but not SPEED) than any equivalent JET engine.

...example: with only 8,760 gallons of 115/145 AVGAS, we (Lockheed EC-121) could stay airborne for 18-20 hours...and still have reserve! Try that in a jet--NOT (ha,ha)!

...that's what "patrol" planes need--endurance, not speed--ie: "time (loiter) on station" to the maximum extent possible.

[Mustang Dave]

Originally Posted by Old Tele man

...after WWII, both (SC & TC) were used together, one example being the turbocompound Curtis-Wright R3350-42 engines, which had a single-stage, two-speed, supercharger and three 'Power Recovery Turbines" (PRTs). The PRTs extracted 500 HP from the exhaust gases from the 18 cylinders and put it back into the engine crankshaft, boosting total output power from 2,900 HP up to 3,400 HP per engine...plus delivering lowest fuel consumption per HP at lean cruise, only about 100 gallons/hr per engine.

Essentially a turbocharger coupled to the crankshaft (other than the 2-speed compressor part).

[gone-ot]

Originally Posted by Mustang Dave

Essentially a turbocharger coupled to the crankshaft (other than the 2-speed compressor part).

...exactly. I still have my copy of the NATOPS manual for the EC-121, and there's a nice picture illustrating how the PRT's worked.

..the coupling between the turbine and the crankshaft wasn't "hard," there was a "fluid coupling" (torque converter) in between each PRT and the crankshaft.

[Mustang Dave]

This past June 26, I went for a tour of a C-121 Constellation. This particular aircraft was Douglas MacArthur's personal transportation during the Korean War. It's airframe and engines are in flyable condition. It resides at the "Planes of Fame" air museum at the Valle airport between Williams and the Grand Canyon.

[gone-ot]

...to meander back to the original posting, "yes," both Super Charging (SC) and Turbo Charging (TC) can and do increase fuel economy, but the combination of BOTH can do even better job (hence, my R3350-42 example above).

...SC both MAKES usable power and TAKES usable power, while TC MAKES usable power from the "waste" exhaust heat and gas flow, hence the "title" Power Recovery Turbine (PRT) on the R3350-42 engines.

...both SC and TC have their own pros & cons.