3000 HP+ 4-engined Aircraft (Piston)

I was just thinking that flyable 4 engined transports with Wright or P&W piston engines designed to generate 3,000 HP or more (at least originally) are a rare commodity out there. Here's what comes to mind:

AHM L-1049H Super Constellation
Former C-121C Super Constellation in Australia
Former C-121C Super Constellation In Europe (Breitling?)
Martin Mars Seaplane/Firebombers in Bristish Columbia (2)
Douglas DC-7 variants ( I don't know how many)
Boeing C-97G Stratofreighter (BAHF and Clay Lacy) (2)

Of course not all of the above are in current flying status today - but they either were recently or will be again hopefully in the not too distant future.

There is no sound I like better than to hear 4 of those big engines turning as one of these aircraft flys over.

(I didn't include the Maurice Roundy L-1649A Starliners because of their very uncertain status as to eventual flyability status again).

Any thoughts?


Jim C.

[planeoldsteve]

FIFI ?

Steve

[planeoldsteve]

Sorry "4 engined transports" The Boeing C-97G Stratofreighter threw me off.

Steve

[Larry Kraus]

Butler Aircraft has 3 flyable DC-7's.
Tanker 60 is an ex-Eastern Airlines DC-7B (N838D).
Tanker 62 is an ex-United Airlines DC-7 (N401US)
Tanker 66 is also an ex-United DC-7 (N6353C)

At least 62 and 66 are contracted to fly as tankers for the State of Oregon this year.60 will be available,as well.

The R3350's we use are a combination of civilian DA and EA series as well as military engines of various dash numbers from Navy and USAF Connies.

The DA series engines were rated at 3250 hp using 115/145 fuel
The EA's developed for the DC-7C's were rated at 3450 hp with 115/145

All of these engines are derated to 2880 hp on 100/130 fuel,which,of course isn't normally available,these days.We do the best we can using 100LL

To reduction in power is achieved by simply reducing the maximum manifold pressure/bmep and watching the gauges carefully.

Sorry "4 engined transports" The Boeing C-97G Stratofreighter threw me off.
Steve

Steve, NO problem at all - my subject title said "4-engined aircraft," I didn't mention 4-engined transports until the body of the message.

I would have included FIFI in my list except that the B-29's had the early Wright R-3350s that generated a maximum of 2,200 HP. The B-50 series and the KC/C-97s developed from the B-29 moved the engines up to P&W R4360s with 3,500 HP. I would put the B-29s in a separate, slightly lower powered category with the DC-6 series and the L-049/649/749 series "short fuselage" Constellations. All of these 4-engine types have piston engines generating max. HP in the 2000 to 2,500 range.



Jim C.

Last edited by jwc50 on Sun Feb 04, 2007 11:02 am, edited 1 time in total.

The DA series engines were rated at 3250 hp using 115/145 fuel
The EA's developed for the DC-7C's were rated at 3450 hp with 115/145

All of these engines are derated to 2880 hp on 100/130 fuel,which,of course isn't normally available,these days.We do the best we can using 100LL

Larry,

Thanks for the insight on the derated engines in these airplanes today. I guess that none of these airplanes with engines originally rated at 3,000 to 3,500 HP, can generate 3,000+ HP today, with the type of fuel available.


Nice to know that those DC-7 series aircraft will be flying this year.

Jim C.

[planeoldsteve]

Sorry "4 engined transports" The Boeing C-97G Stratofreighter threw me off.
Steve

Steve, NO problem at all - my subject title said "4-engined aircraft," I didn't mention 4-engined tranports until the body of the message.

I would have included FIFI in my list except that the B-29's had the early Wright R-3350s that generated a maximum of 2,200 HP. The B-50 series and the KC/C-97s developed from the B-29 moved the engines up to P&W R4360s with 3,500 HP. I would put the B-29s in a separate, slightly lower powered category with the DC-6 series and the L-049/649/749 series "short fuselage" Constellations. All of these 4-engine types have piston engines generating max. HP in the 2000 to 2,500 range.



Jim C.

Do you know if FIFI's new Engines will be DA or EA"s and what the horse power will be?

Maybe we can ask Gary, are you out there?

Steve

[retroaviation]

Do you know if FIFI's new Engines will be DA or EA"s and what the horse power will be?
Maybe we can ask Gary, are you out there?
Steve

This is a question that I answer daily to museum guests. I'll give you the "short" version, and if y'all have any further questions or comments, I'll do my best to answer them. Maybe I should start a new thread with this? I don't want to hijack Jim's original thread here, but it is sort of relevant.

We will be turning two different dash numbered 3350's into one. We are starting with the -26WD (Skyraider engine) and the -95W (AC-119 Gunship) engine. We will be using the power section (the "block"), blower section, and accessory section of the -26WD, since it will actually fit on the original engine mount of the B-29. We will use the rotating assemblies (crank, rods, pistons, cams, etc.), cylinders, and nosecase of the -95W.

The -95W was a Turbo Compound engine (w/power recovery turbines...PRT's), but we obviously won't be using the PRT stuff. The engine was supposedly rated at 3500 hp, and the "guts" for it are quite strong. The airframe on the B-29 was never meant to handle 3500 hp per engine, so we will be derating the engine's power. With some number crunching by people waaaaay smarter than me, if we use 40" of manifold pressure and 2400 rpm at takeoff, the engines should produce around 2400 hp each. The airframe will take that additional 200 hp per engine (again, figured out by really smart people), and the prop tip speeds will only be approximately 50 rpm more than they turn on takeoff now...so they may have a little more "buzz" on takeoff, but should still be efficient. This power setting will also be plenty to keep the rings seated and won't be "too easy" on the bottom end of the engine, yet it will be using much less power than it's potential, which should increase reliability.

This should also be a huge safety factor, as we will have more power available, if necessary, in an emergency situation.

So, there's the short version. Sorry to hijack the thread, but it looks like with the horsepower we'll actually be using with the new engines, we still wouldn't qualify to be listed on this thread.

Gary

Gary:

You are not "hijacking" this thread at all. Your information regarding what is happening with the re-built Wright R-3350's going into FIFI is very interesting. I didn't realize that different versions of the engine were being utilized.

It will be interesting to see if most observers will be able to detect any difference in sound on takeoff with the additional 200 HP per engine allowing up to the 2,400 HP level.

The airframe/wing structures of the B-50s and the C-97's must have been strengthened to a significant degree to allow the mounting and operation of the Pratt & Whitney R-4360's and their 3,500 HP ratings.


Jim C.

[planeoldsteve]

Thanks for all the information on the engines, Gary

Steve

[Larry Kraus]

That's an interesting insight as to the power use for Take-Off in the B-29.The STC that we have for the DC-7 using DA and EA engines allows (at sea level/standard day): 53" hg and 234 bmep at 2900 rpm for Take-Off.Our METO power is 43.5" hg and 212 bmep at 2600 rpm,with a Climb power of 36" hg and 175 bmep at 2400 rpm.This is all predicated on using 100/130 fuel.

The military engines from Connies differ slightly by dash number on Take-Off manifold pressure,but everything else is the same.I think that the -42's only allow 50" and the others are 51' and 52".I'm assuming slightly different blower ratios,as the bmep limits are all 234.Personally,I use 50" as a manifold pressure limit.Normally,we reference the manifold pressure and cross check bmep on T/O and METO,then switch to using bmep and cross checking manifold pressure at Climb and lower power settings.The manifold pressure gauges are easier to read (we don't have an engineer) and exceeding the bmep limits is less likely than exceeding manifold pressure during the summer months at high power settings,although we occasionally have a strong engine that hits the bmep limit first.

The last word that I had from the P2V tanker operators,was that their STC allows for 51" hg with 100LL in both the SP-2E's and SP-2H's.The P-2's engines are Turbo-Compound,but with carburetors and one injector into the eye of the blower,rather than direct injection at the cylinders.This allows them to use water injection,although I'm not sure if any of them use it these days.

The DC-7 engines are all Turbo-Compound with direct fuel injection.By the way,Gary,if you end up with some PRT's,or even parts of PRT's that are in good shape that you don't need,contact me and I'll check with Butler's Director of Maintenance,as we are always looking for PRT's.

[retroaviation]

We should end up with a whole pile of PRT's by the time this is all said and done. I'll see that you get first dibs at 'em.

Gary

[IRONHORSE]

Are there any flyable C-124's?
CHUCK

[leo]

I think the last C-124 flight was the Travis Air Museum's delivery flight in the mid-80's. What a sight and sound, it circled the area and gave all the old-timers a treat before landing for the last time.
It's kept in great condition but I'm sure it's not flyable, tho it may be the closest to it.

I think the last C-124 flight was the Travis Air Museum's delivery flight in the mid-80's. What a sight and sound, it circled the area and gave all the old-timers a treat before landing for the last time.
It's kept in great condition but I'm sure it's not flyable, tho it may be the closest to it.

Chuck, Leo:

I really wish we could put the C-124 on this list. Just as you say Leo, more than 10 years after the last operational flight of the Globemaster II in 1974, I believe that about October of 1984 this last C-124 flight was made from Georgia to California. I sure wish I could have seen it. Someone else told me several years ago that things were done to this aircraft after arriving at Travis that would make it very difficult to return to a flyable condition again.

I think the late model C-124C's and some of the late models of the B-36 were the only piston-engined miltary aircraft to have the version of the R-4360 that could generate up to a maximum of 3,800 HP.

The C-124 was one of my favorites, and I don't think I have seen or heard one in flight since about 1970/71.

Jim C.