BillS Posted May 26, 2021 Share Posted May 26, 2021 As I continue to dream of getting my paws on this kit, i noticed on the images of sprue and built components, the CSD (Constant Speed Drive) is the USAF type. Air Force -15 and 17 J-79’s had a cartridege start feature mounted on the gearbox mounting pad where the Navy’s CSD/Generator was located. So, the cart start system necessitated moving the CSD/Generator to the compressor front frame. The Air Force unit was longer and had the two struts that carried oil to that system. The -8 and -10 motors had a shorter, more conical fairing. I also think the nice engine detail representing what’s visible through the auxiliary air doors has the breech feature molded on as well but can’t tell for sure until I see these pieces in person. Anyway, these are small things to address for the pedantic among us. On my 4 ZM J’s I forgot all about this but I did remember the Rate of Roll light I’m always harping about! Quote Link to post Share on other sites
ChesshireCat Posted May 26, 2021 Share Posted May 26, 2021 Bill; you do know your talking way over me head! <g> gary Quote Link to post Share on other sites
BillS Posted May 26, 2021 Author Share Posted May 26, 2021 Sorry for speaking”Phantomese”! On the very front of the engine there’s a protuberance sticking out of the middle. On USAF jets there are two “arms”, one at 5 o’clockish the other at 7. On USN/USMC this protuberance was much shorter and minus the arm thingys. To be able to operate in the field with minimal ground support equipment, the Air Force wanted to be able to start the engines with an explosive cartridge. This cartridge was about the size of a coffee can. The breech for this thing was on the engine mounted gearbox where other accessories like the hydraulic pump etc. This system was accessed near the auxiliary air doors for each engine in the center belly. In reality, this system wasn't used all of the time because it made a mess with carbon residue. The purpose of the CSD/Generator was to produce electrical power. The CSD was turned by the engine and through gears, it kept the generator turning at a constant rate until the engine fell below a certain RPM, 80% I think. Since the Navy/Marines didn’t have cart start, their CSD/Generator could be mounted on the gearbox. You can search General Electric J-79 and find lots of pics. All of the resin inlet sets, the Zouki Muru and now Tamiya F-4s all nicely depict the USAF style inlet. The accuracy folks can alter this with little effort. I hate to cut Tamiya plastic but I’ll probably fix this on the ones I build. Quote Link to post Share on other sites
Ben Brown Posted May 27, 2021 Share Posted May 27, 2021 (edited) Here is the Air Force engine. Those two "fins" coming out of the bullet-shaped fairing on the front of the engine are the ones Bill is talking about. Here is a good picture showing the oil pipes going through the "fins" (photo is a little large so I've linked to it): PHOTO LINK Here is the Navy engine with the different bullet fairing. EDIT: See Dave’s post below for a Navy J-79. Apparently, I posted a photo of an F-104 engine. Ben Edited May 27, 2021 by Ben Brown Quote Link to post Share on other sites
airmechaja Posted May 27, 2021 Share Posted May 27, 2021 What amazes me is someone as old as me remembers cart starts! They were great to watch. Quote Link to post Share on other sites
JeffreyK Posted May 27, 2021 Share Posted May 27, 2021 Witnessed a double cart start at the Luftwaffe's "Phantom Farewell" in Wittmund, 2013... Probably doesn't count Oh and, I didn't know Vlad Putin was working for GE back in the day pushing engine carts J Quote Link to post Share on other sites
Dave Roof Posted May 27, 2021 Share Posted May 27, 2021 (edited) I'm sorry, but I just looked through a number of books, as well as photos on-line and it appears Tamiya did in fact get it correct. The F-4B used the J79-GE-8 and everything I've found shows the bullet fairing matches what Tamiya provides. The bullet fairing on the J79 in the photo that Ben posted appears to be from a J79-GE-11 and used on the F-104G/J. -8's being maintained in Da Nang - Photo by Bob Mann Edited May 27, 2021 by Dave Roof Quote Link to post Share on other sites
phantom Posted May 27, 2021 Share Posted May 27, 2021 5 hours ago, JeffreyK said: Oh and, I didn't know Vlad Putin was working for GE back in the day pushing engine carts J Well, he was Russian spy! First engine, then Moose and squirrel. Quote Link to post Share on other sites
Ben Brown Posted May 27, 2021 Share Posted May 27, 2021 @Dave Roof, so that’s why I’ve never seen an aftermarket F-4 intake with a pointy fairing! 😄 Thanks for correcting me! Ben Quote Link to post Share on other sites
Dave Roof Posted May 27, 2021 Share Posted May 27, 2021 10 minutes ago, Ben Brown said: @Dave Roof, so that’s why I’ve never seen an aftermarket F-4 intake with a pointy fairing! 😄 Thanks for correcting me! Ben @Ben Brown Hey, well at least you didn't spend a few minutes working on a "correction" only to realize it wasn't needed! Quote Link to post Share on other sites
Ben Brown Posted May 27, 2021 Share Posted May 27, 2021 D’oh! Ben Quote Link to post Share on other sites
niart17 Posted May 27, 2021 Share Posted May 27, 2021 I thought he was talking about the 2 fins that come off the fairing at an angle toward the bottom front lip, not the shape of the fairing itself? But it's all Greek to me so... Quote Link to post Share on other sites
Dave Roof Posted May 27, 2021 Share Posted May 27, 2021 8 minutes ago, niart17 said: I thought he was talking about the 2 fins that come off the fairing at an angle toward the bottom front lip, not the shape of the fairing itself? But it's all Greek to me so... Well, either way, those aren't in the kit. Quote Link to post Share on other sites
BillS Posted May 27, 2021 Author Share Posted May 27, 2021 DAVE, Thanks for posting the great pic of the Marine dudes in the shelter. That and Ben’s postings illustrate what I what I mean. As far as Tam’s rendition, there a pic of the internal build up of Tam’s innards and to me it looked like they have the long fairing ala USAF. Run over to the thread on Hyperscale titled “Afterburner Length” and you'll see that image on the first page. It really is just a point of interest and should not detract from this very exciting new kit. Quote Link to post Share on other sites
Dave Roof Posted May 27, 2021 Share Posted May 27, 2021 39 minutes ago, BillS said: DAVE, Thanks for posting the great pic of the Marine dudes in the shelter. That and Ben’s postings illustrate what I what I mean. As far as Tam’s rendition, there a pic of the internal build up of Tam’s innards and to me it looked like they have the long fairing ala USAF. Run over to the thread on Hyperscale titled “Afterburner Length” and you'll see that image on the first page. It really is just a point of interest and should not detract from this very exciting new kit. Bill, I can assure you Tamiya got it correct and what is shown on HS isn't indicative of what's in the kit. That fairing, part D22 in the kit, measures out to 19 scale inches. When placed in the compressor face, part D5, it matches the real engine perfectly. Quote Link to post Share on other sites
BillS Posted May 28, 2021 Author Share Posted May 28, 2021 The picture Ben posted is a USAF either -15 or -17; can’t tell because the exhaust nozzle isn’t really visible. In looking over the sprue shots Tamiya has modeled the Air Force style lumbar pad and emergency o2 bottle which is molded as a small appendage on the left where the aircrew’s left lower back is. The Navy seat had the emergency o2 in the survival kit, so the lumbar pad was symmetrically shaped. ZM actually correctly molded the o2 gauge on the seat cushion applicable to USN/USMC. I hate to say it but those afterburners look pretty undersized in length. Not trying to be petty, just saying. Quote Link to post Share on other sites
CF104 Posted May 28, 2021 Share Posted May 28, 2021 (edited) On 5/27/2021 at 10:20 PM, BillS said: The picture Ben posted is a USAF either -15 or -17; can’t tell because the exhaust nozzle isn’t really visible. In looking over the sprue shots Tamiya has modeled the Air Force style lumbar pad and emergency o2 bottle which is molded as a small appendage on the left where the aircrew’s left lower back is. The Navy seat had the emergency o2 in the survival kit, so the lumbar pad was symmetrically shaped. ZM actually correctly molded the o2 gauge on the seat cushion applicable to USN/USMC. I hate to say it but those afterburners look pretty undersized in length. Not trying to be petty, just saying. The J79 photo posted by Ben is a -15A short nozzle. Along with it being noted on the display board on the engine stand, it is equipped with a short nozzle. This is also visually confirmed by the longer outer shroud of the short nozzle and the fact you can see through the primary/secondary nozzle flaps gap. The -17 has a short shroud and you can't see through the long nozzle flaps gap as well. As for the ejection seat lumbar pad, the mistake can be easily corrected by cutting off the emergency O2 bottle(as shown in the instructions) and filling in the notch. BTW, I have never seen a kit ejection seat done perfectly and this is why I always go with aftermarket seats. If you're talking about the exhaust duct length, I agree that they look a bit short. For detail nuts, I'm sure there will be aftermarket for this as well. Cheers, John Edited May 29, 2021 by CF104 clarification Quote Link to post Share on other sites
Dave Roof Posted June 3, 2021 Share Posted June 3, 2021 On 5/28/2021 at 12:20 AM, BillS said: The picture Ben posted is a USAF either -15 or -17; can’t tell because the exhaust nozzle isn’t really visible. In looking over the sprue shots Tamiya has modeled the Air Force style lumbar pad and emergency o2 bottle which is molded as a small appendage on the left where the aircrew’s left lower back is. The Navy seat had the emergency o2 in the survival kit, so the lumbar pad was symmetrically shaped. ZM actually correctly molded the o2 gauge on the seat cushion applicable to USN/USMC. I hate to say it but those afterburners look pretty undersized in length. Not trying to be petty, just saying. Just an FYI, but the Tamiya part measures 13 scale inches when using a 1/48 scale ruler. Pretty much a dead on match to the real thing. Photo and measurement courtesy of the curator from the Flying Leathernecks Museum at MCAS Miramar. Quote Link to post Share on other sites
CF104 Posted June 5, 2021 Share Posted June 5, 2021 On 6/3/2021 at 12:55 PM, Dave Roof said: Just an FYI, but the Tamiya part measures 13 scale inches when using a 1/48 scale ruler. Pretty much a dead on match to the real thing. Photo and measurement courtesy of the curator from the Flying Leathernecks Museum at MCAS Miramar. Thanks for the photo. I think the OP, BillS, was commenting on the exhaust duct length and not the nozzle length. I think the kit nozzle looks pretty good from what I've seen of the sprue shots. Those same sprue shots do show a possibly shortened duct but that's totally splitting hairs as far as I'm concerned. Can't wait to get a couple of these kits. Cheers, John Quote Link to post Share on other sites
bashace Posted July 28, 2021 Share Posted July 28, 2021 On 5/27/2021 at 7:01 AM, JeffreyK said: Witnessed a double cart start at the Luftwaffe's "Phantom Farewell" in Wittmund, 2013... Probably doesn't count Oh and, I didn't know Vlad Putin was working for GE back in the day pushing engine carts J I think I may have captured that on video, was a wet day if I remember correctly. Quote Link to post Share on other sites
GeneK Posted July 28, 2021 Share Posted July 28, 2021 Dave Roof, I can't see your pictures (Chrome, Edge, and Firefox). Change host? Gene K Quote Link to post Share on other sites
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