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.
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.
How many fuel injectors did it have?
KJ_Lesnick said:
Understood...
Understood...
I'm unsure... maybe the compressor looks too short to stuff that many stages of compressors in there?
I'm not sure though you'd typically use plumbing fittings in a jet to pump in fuel or oil for lubrication...
That's a good observation. The best way to get to ground truth would be to split the case and count the stages, but I don't think that Mr. Maloney would let us do that to his exhibit. Let's attack this by analogy. What was the state of the art at the time and for some years after? Go find the number of compressor stages for the following engines and report back. (also note thrust and compression ratio)KJ_Lesnick said:
Well, I was being a bit generic in my description. To be technical, those would be "AN" standard aviation fluid fittings - but why do you think that they would pump a fluid through the engine front frame? (Hint: take a close look at Tartle's photo.)
Curators get so bent out of shape over that... *laughs*
During the early 1940's there weren't many axial flow engines out there. These engines would include the BMW 003 (1940), Jumo 004 (1940), (possibly the HeS 8 and 11), the Metropolitan F.2/4 Beryl (1941), the Metropolitan Vickers F.3 (Turbofan technically).
Wilco...
The tubing flows through a structure in the middle of the engine which might be the intercooler that was mentioned; it then flows through to the afterburner in three locations which appear to include the fuel injectors and two other spots.
32 stages goes right off the chart, it would appear you'd have around 20:1...
tartle said:
"By the time it was developed enough for production use, other engines, often British-derived, had surpassed it in performance. The design was later converted to a turboprop, the T35 and still later sold to Wright Aeronautical, where it saw some interest for use on what would become the B-52 Stratofortress, before that design moved to jet power. The J37 and T35 were built to the extent of a number of testbed examples but never entered production." That is straight from Wikipedia, dont know how reliable that info is.
Hi Robin, yes I've had those T35 cross-sections on my PC for exactly 10 years yesterday (so my going on a propulsion kick must be seasonal!). I've been known to tell the difference between axial and centrifugal but not always.
My poorly made point was that even otherwise decent publications make the T35/J37 connection (there was supposed to be a roll-eyes smiley in there somewhere!).
Very nicely done! I didn't have time to go through all of it (yet) but the Menasco section was quite illuminating and I really heartily approve of your References section!
I agree completely. Unfortunately, public domain primary sources are in short supply. The huge cache of documents the USAF gave to NARA after about 1950 are in limbo (probably permanently) at the St. Louis Records Center. There have been several attempts to get those records declassified and cataloged, including one last year, but these efforts never seem to get past the talking stage. Company information is mostly either secret or proprietary. In addition to all that, it takes many, many hours to properly research and write and article if your have the data.
Thank you. I hope you enjoy it.
