And so removing armour and wing guns is the basis of all your 1,750 posts? What about the input of the Russians who wanted more armour in certain places to stay alive, which is quite important I am told.
Groundhog Thread Part Deux - P-39 Fantasy and Fetish - The Never Ending Story (Mods take no responsibility for head against wall injuries sustained) (1 Viewer)
- Thread starter greybeard
- Start date
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GrauGeist
Generalfeldmarschall zur Luftschiff Abteilung
He's read manuals and held up "drawings" for comparison.
He's also observed a static P-39 display at a museum.
In light of these details, it's obvious that we're dealing with a highly qualified internet Aerospace Engineer...
FLYBOYJ
"THE GREAT GAZOO"
"Construction drawings" A new one...
In balance
combat power
tail cone
landing reserve
In my work I was concerned with refineries and oil installations (at times). I frequently heard the expression "approved for construction" or "issued for construction" with regard to drawings, but this is a different branch of engineering. The important drawings in this conversation would be what I heard being discussed as the "as built" drawings.
FLYBOYJ
"THE GREAT GAZOO"
At Lockheed we also had "Production Illustrations" (PIs) that had a 3-D view of an installation that might not have been made clear on installation drawings. They were really helpful for wire harness routing within a confined area.
Another aspect is the production tooling which is the actual linchpin in aircraft constriction. In my experience in building up sub assemblies, the tooling dictated the final outcome and there was always a war in ensuring the tooling matched assembly or installation drawings.
Funny thing too was Lockheed was late in introducing GDT.
FLYBOYJ
"THE GREAT GAZOO"
First time I heard that term is when I was assigned to Canadair as a QA Rep on the CP-140 program many years ago.
GrauGeist
Generalfeldmarschall zur Luftschiff Abteilung
When I was outfitting Fire apparatus, we'd submit a 3D illustration of the proposed wire routing to the equipment called a "Final Stage Illustration" during meetings with the agency.
All nations and industries are different. Sometimes there were various solutions proposed to the client as drawings for approval, at other times many solutions were proposed and fabricated on site (with no client involvement) and the solution to the problem was included in the "as built" drawing submitted to the client. A lot depended on the scope and involvement of the end client, in the oil industry, the end client frequently wants to off load as much responsibility as possible, in case something goes wrong. In WW2 aviation it was usually but not always different.
That is why I stopped making serious posts to him to begin with.
Wait, I was serious when I said the only thing he has proven is that he cannot read or use simple charts.
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Thumpalumpacus
Major
He clearly only replies when he thinks it offers him an opportunity to advance his agenda.
I've been dogpiled before (elsewhere, obvs) , and while it's hard, it's doable, by collating posts and answering multiples with one reply.
P-39 Expert
's problem seems to be that he's making so many questionable claims and facing pushback from so many different angles that he's tying himself into knots trying to 1) answer an objection and 2) do so in such a manner that he doesn't undercut another answer of his to another objection.
Hence appealing to different variants of the P-39, or even appealing to the P-63, and hoping no one notices that he's engaged in overlarge equivocation. Or, as I have it saved as a smiley:
I've been dogpiled before (elsewhere, obvs) , and while it's hard, it's doable, by collating posts and answering multiples with one reply.
P-39 Expert
's problem seems to be that he's making so many questionable claims and facing pushback from so many different angles that he's tying himself into knots trying to 1) answer an objection and 2) do so in such a manner that he doesn't undercut another answer of his to another objection.Hence appealing to different variants of the P-39, or even appealing to the P-63, and hoping no one notices that he's engaged in overlarge equivocation. Or, as I have it saved as a smiley:
GregP
Major
Hey P-39 Expert. We all KNOW the engine compartment (the part where the power section goes ... you know, the engine block and cylinders) is the same size because the same engine block fits into it. What ISN'T the same size is the compartment aft of the engine compartment, where the auxiliary stage would go. I just got back from the museum and measured things on both the P-39 and the P-63. Go back to post #3,403 and look at the P-39 side views.
Notice the bulkhead just below the antenna mast and the bulkhead just aft of the rearmost exhaust stack. From the bulkhead under the antenna mast to the aft exhaust stack is 3" 9" on a P-39 (the one I used is a P-39N) and 4' 5" on the P-63. If you subtract the smaller measurement from the larger measurement, the difference is 8 inches using the "Measure" app on my cell phone. Doesn't sound like much, but it is the difference between the Aux stage fitting and not fitting. Also, the rear area in the P-63 is big enough for the Aux stage supercharger. In the P-39, it is NOT big enough for the aux-stage to fit inside. As I stated in an earlier post, you COULD knock some sheet metal out to shoehorn it in, but then you'd STILL have the CG issue that requires moving the wing or the pilot and you'd STILL have to supply a bearer mount for the aux stage after you move the existing bulkhead and whatnot back there, like oxygen bottles. Moving the pilot forward would put him firmly in the cannon breech area, so he'd not likely relish that idea. Seems better to move the wings aft a bit for CG purposes.
Hence, the P-63 Kingcobra, with all the changes built in to make a aux-stage Allison work.
You CANNOT fit a 2-stage Allison into a stock P-39 airframe and, if you DID by banging sheet metal around, the aux stage would have no support to mount on, and it would rock back on the tail.
Not sure what you are thinking, but I have had two different museums that own P-39s, one of which has restored both P-39s and P-63s to flight status, tell me a 2-stage Allison won't fit in a P-39. My own measurements confirm that. Now, I can't show you a 2-stage Allison installation in our P-63, because ours is being restored with a single-stage engine, but there are several such pictures floating about. Here is one:
https://ww2aircraft.net/forum/attachments/p-63-ephrata-airfield-july-44-jpg.356901/
You can see the compartment aft of the power section is pretty full.
If you want to insist that you can make an aux-stage Allison fit into a P-39, please feel free. Nobody ELSE can get it done. Perhaps you can get into Mr. Peabody's WayBack Machine and go back to show them all how it is done. Failing that, since Sherman and Mr. Peabody might not be very cooperative, SHOW ME HOW TO DO IT. Get Allison Aux-stage engineering drawings and a Bell P-39 engineering drawings and show that the equipment and the supports fit where everyone else says they won't fit. Show it clearly and with measurements, accounting for everything needed to make a 2-stage Allison run.
Or ... please stop making that claim.
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fubar57
General
Greg…..just who do you think you are bringing measurements and fact to this thread
GregP
Major
Sorry, I forgot, I'm just a former (not current) pilot. So, my posts must be hearsay.
fubar57
General
FLYBOYJ
"THE GREAT GAZOO"
Great info Greg - and I like the way our friend talks about moving structure and components around as if he was kitbashing a 1/48th scale P-39 model (no disrespect to my modeling friends). No mention of having to place this "Frankenstein" into a jig so the rest of the structure doesn't warp or bend. Sure, at the factory "they" can do almost anything, get that Wayback machine and send our friend to Bell around 1941, he could have been the VP of P-39 Engineering and Production!
EDIT - I better watch that, he might start believing he was qualified to hold such a position!
Thumpalumpacus
Major
Well, did you read the manual? That should be sufficient qualification.
FLYBOYJ
"THE GREAT GAZOO"
It's been a while since I knocked around this site, but some great Allison V1710 info.
V-1710-E engines were designed for use with remote gearboxes. Three variants powered single-engine Bell P-39 (LF, RF, Firing), P-63 and XFL-1 fighters, all of which had the engine behind the pilot. This arrangement made room for a 37mm cannon firing through the propeller hub. A fourth variant powered the Douglas XB-42. P-39 engines used single-stage superchargers, while some P-63 engines added a variable-speed auxiliary altitude supercharger stage (LF, RA). The XB-42 employed two V-1710-E23 (L, RF) engines to drive contra-rotating pusher propellers. A turbocompound engine, the V-1710-E27 (L, A, R, T) was built and tested, as were numerous other variations on the shaft-driven remote gearbox (90°, Tandem, Tandem).
V-1710-E Images: F, LF, L, LA, A, RA, R, RF, T, B, with Driveshaft, Gearbox.
I believe this is what the 2 stage V-1710 engine looked like (V-1710-G)
Here's the stock P-39 engine
Here's the gearbox - "Just Because"
S Shortround6 any comments?
V-1710-E engines were designed for use with remote gearboxes. Three variants powered single-engine Bell P-39 (LF, RF, Firing), P-63 and XFL-1 fighters, all of which had the engine behind the pilot. This arrangement made room for a 37mm cannon firing through the propeller hub. A fourth variant powered the Douglas XB-42. P-39 engines used single-stage superchargers, while some P-63 engines added a variable-speed auxiliary altitude supercharger stage (LF, RA). The XB-42 employed two V-1710-E23 (L, RF) engines to drive contra-rotating pusher propellers. A turbocompound engine, the V-1710-E27 (L, A, R, T) was built and tested, as were numerous other variations on the shaft-driven remote gearbox (90°, Tandem, Tandem).
V-1710-E Images: F, LF, L, LA, A, RA, R, RF, T, B, with Driveshaft, Gearbox.
I believe this is what the 2 stage V-1710 engine looked like (V-1710-G)
Here's the stock P-39 engine
Here's the gearbox - "Just Because"
S Shortround6 any comments?
Thumpalumpacus
Major
It's been a while since I knocked around this site, but some great Allison V1710 info.
V-1710-E engines were designed for use with remote gearboxes. Three variants powered single-engine Bell P-39 (LF, RF, Firing), P-63 and XFL-1 fighters, all of which had the engine behind the pilot. This arrangement made room for a 37mm cannon firing through the propeller hub. A fourth variant powered the Douglas XB-42. P-39 engines used single-stage superchargers, while some P-63 engines added a variable-speed auxiliary altitude supercharger stage (LF, RA). The XB-42 employed two V-1710-E23 (L, RF) engines to drive contra-rotating pusher propellers. A turbocompound engine, the V-1710-E27 (L, A, R, T) was built and tested, as were numerous other variations on the shaft-driven remote gearbox (90°, Tandem, Tandem).
V-1710-E Images: F, LF, L, LA, A, RA, R, RF, T, B, with Driveshaft, Gearbox.
I believe this is what the 2 stage V-1710 engine looked like (V-1710-G)
View attachment 634592
Here's the stock P-39 engine
View attachment 634593
Here's the gearbox - "Just Because"
View attachment 634594
S Shortround6 any comments?
Where dos the cannon fit into this? Anyone have any pics? Wiki's kakking out on me.
