Lockheed XJ37 turbojet engine

[Steve Pace]

The proposed 5,000lb thrust Lockheed XJ37 axial-flow turbojet engine was ahead of its time. Two of them were to propel the proposed Lockheed L-133 interceptor pursuit. Lockheed eventually sold the engine to Menasco (I think?) but I don't know what happened to it after that.

[Bailey]

Have a look here: http://hyperscale.com/features/2002/l133tc_1.htm

Regards Bailey

[Bailey]

Bit more here:

http://en.wikipedia.org/wiki/Lockheed_J37

Cheers Bailey

[Archibald]

You mean, the L-1000 ?

[Steve Pace]

Yes, the L-1000.

[PNorwood]

Does anybody have a cut-away of that engine?

[aim9xray]

I had the chance this last weekend to visit the Planes of Fame Museum at Chino, California.  In the "early jets" hangar, I found an example of the L-1000 / XJ37 engine.  In the 60-odd years since it's creation, the engine has suffered some "hangar rash" (dents and dings); in addition it appears that almost all of the external tubing and wiring is missing (if it was there to begin with - this may have been an engineering mockup from the beginning).

Several features are noteworthy - the large number of fuel injectors is unusual to say the least.  Note also the ejector exhaust that draws outside air into the tailpipe for added thrust and to create a boundary layer of cooling air to protect the tailpipe stricture.

[KJ_Lesnick]

aim9xray

I had the chance this last weekend to visit the Planes of Fame Museum at Chino, California.  In the "early jets" hangar, I found an example of the L-1000 / XJ37 engine.

Several features are noteworthy

Almost everything on that engine was noteworthy: It had a twin-spool compressor of which the LP and HP had sixteen stages apiece; the compressor lacked discs as would normally be seen -- the blades were mounted to a drum.  The first four stages actually were hydraulically clutched, and inter-cooling was located between the HP and LP spools.  Though earlier models had a can-annular configuration, this model had an annular configuration.

Note also the ejector exhaust that draws outside air into the tailpipe for added thrust and to create a boundary layer of cooling air to protect the tailpipe stricture.

The exhaust was used to pull turbulent air from the top and bottom of the wing which form particularly at high subsonic speed (it was designed to go supersonic at least in a dive).  Such airflow would provide cooking for the tailpipe which had an afterburner by 1940-1941.

the large number of fuel injectors is unusual to say the least.

How many fuel injectors did it have?

[aim9xray]

the large number of fuel injectors is unusual to say the least.

How many fuel injectors did it have?

With reference to the photo above (titled "L-1000 Fuel Injection"), count the number of "pigtails" leading from the manifold to the fuel injectors.  Multiply by two (to account for those hidden on the other side) and report back.

When you do, we can discuss why the descriptions on Wikipedia are sadly and grossly out of sync with the actual hardware that was produced.

[KJ_Lesnick]

aim9xray


I count between (24-27 depending on wrap-around) 48-54.

[aim9xray]

Great!  One question answered. I was counting 24-25 visible, so we are in the ballpark.

OK, then - lets start at the front of the engine.  Wikipedia stated that there were 16 stages of low pressure compressor and 16 stages of high pressure compressor with intercooling between them.  (Nevermind the "four stages hydraulically clutched").

Looking at the photos of the hardware (and from general turbojet knowledge), I don't think that is so.  What would lead me to me to that opinion?

(And while we are looking at the front of the engine, why do you think that the front frame has some 90 degree plumbing fittings attached?)

[KJ_Lesnick]

aim9xray

Great!  One question answered.

Understood...

OK, then - lets start at the front of the engine.  Wikipedia stated that there were 16 stages of low pressure compressor and 16 stages of high pressure compressor with intercooling between them.  (Nevermind the "four stages hydraulically clutched").

Understood...

Looking at the photos of the hardware (and from general turbojet knowledge), I don't think that is so.  What would lead me to me to that opinion?

I'm unsure... maybe the compressor looks too short to stuff that many stages of compressors in there?

(And while we are looking at the front of the engine, why do you think that the front frame has some 90 degree plumbing fittings attached?)

I'm not sure though you'd typically use plumbing fittings in a jet to pump in fuel or oil for lubrication...

[tartle]

Busy editing book at moment so will look at this engine later...in meantime from the Tardis-like tea chest....
tbc

[Steve Pace]

neato

[tartle]

Has anyone got access to SAE papers... apparently this has some stuff on Menasco (for Lockheed) gas turbines:
 Rinek, L., "Menasco Aircraft Engines: Air Racing Paragon of the 1930s," SAE Technical Paper 965598, 1996