PB4Y-2 Privateer (Matchbox, 1980 vintage)

[stevehnz]

Most of the drawings I have found show the cutaway rear to the outer nacelles, conversely, I haven't found a photo that I would say confirms this but several that clearly show the "boat prow" shape. Such as this one.

Photo used as appears to be in public domain, happy to change it to a link if anyone thinks it should be. From this website. I got the Ginter PB4Y-2 post in the mail today but have not had much chance to look at it, I'll be keen to see what it has to say on this.

Steve.

[Marcello Rosa]

I only had one photo which I used to reassure me. It was not perfect, but t did look like the outer being cut flat was at least possible:

 

[stevehnz]

Not an easy thing to be sure off either way, that photo was one I couldn't be sure of, I felt it was possible to interpret both rear ends from it & given the dearth of favourable photos it is easy to see how the confusion creeps in. There may well have been both types of nacelle, I haven't found anything definitive at this stage.

Steve.

[Marcello Rosa]

Yes, I agree. Let us know what you find in the book. Too late for my build, but maybe if we can clarify this it will help the next person.

[stevehnz]

12 hours ago, Marcello Rosa said:

maybe if we can clarify this it will help the next person.

I don't expect to be the next person by any stretch but will certainly find the book, "Naval Fighters 93, Convair PB4Y-2/P4Y-2 Privateer" by Veronico & Ginter, very useful for such corrections as I care to make. Regarding the outer nacelles, I would be confident now correcting them to the kind of boat shape, as shown in the photo I posted above, certainly no evidence of D-shaped cutouts, this is illustrated clearly on page 29 of the book in a break down of components diagram, numerous photos through the book bear this out too.

Steve.

[Navy Bird]

2 hours ago, stevehnz said:

I don't expect to be the next person by any stretch but will certainly find the book, "Naval Fighters 93, Convair PB4Y-2/P4Y-2 Privateer" by Veronico & Ginter, very useful for such corrections as I care to make. Regarding the outer nacelles, I would be confident now correcting them to the kind of boat shape, as shown in the photo I posted above, certainly no evidence of D-shaped cutouts, this is illustrated clearly on page 29 of the book in a break down of components diagram, numerous photos through the book bear this out too.

 

I just checked through every page in the Naval Fighters #93 volume and I agree with your assessment. The only photo that made me wonder was on page 102 of BuNo 59350, the first production aircraft. This is shot is from directly behind, and at first glance it looks like there is a D-shaped cutout at the back of the outer nacelle on the port side. On closer inspection I think it's just exhaust staining or something like that.

 

Cheers,

Bill

[stevehnz]

46 minutes ago, Navy Bird said:

 

I just checked through every page in the Naval Fighters #93 volume and I agree with your assessment. The only photo that made me wonder was on page 102 of BuNo 59350, the first production aircraft. This is shot is from directly behind, and at first glance it looks like there is a D-shaped cutout at the back of the outer nacelle on the port side. On closer inspection I think it's just exhaust staining or something like that.

 

Cheers,

Bill

I did look at that & came to the same conclusion. The photo below those two rear on ones is also 59350 albeit 5 weeks later, & it very clearly has the boat hull shaped rears to the nacelles. I guess the D cut out was a B-24 thing & as such likely to do with venting heat from the turbocharger area. I don't know if any of the PB4Y-2 prototypes had this as a carry over from their B-24 ancestry, I haven't looked into that yet. (later) There is at least one photo of the XPB4Y-2 prototype with B-24 style nacelles & turbochargers, also still with twin fins so more a B-24 with PB4Y-2 fuselage.

Steve.

[Vinnie]

Impressive work, Marcello. Well done.

[Homer]

"BEAUTIFUL "

[Marcello Rosa]

On 30/06/2021 at 09:39, stevehnz said:

I did look at that & came to the same conclusion. The photo below those two rear on ones is also 59350 albeit 5 weeks later, & it very clearly has the boat hull shaped rears to the nacelles. I guess the D cut out was a B-24 thing & as such likely to do with venting heat from the turbocharger area. I don't know if any of the PB4Y-2 prototypes had this as a carry over from their B-24 ancestry, I haven't looked into that yet. (later) There is at least one photo of the XPB4Y-2 prototype with B-24 style nacelles & turbochargers, also still with twin fins so more a B-24 with PB4Y-2 fuselage.

Steve.

I think this discussion will be very useful for future builders of this model.

What I find interesting about this whole affair is the disconnection between photos available online and most, if not all diagrams. Even stuff you download from the USN web site shows the outer nacelle cut flat:

 

https://www.history.navy.mil/content/dam/nhhc/research/histories/naval-aviation/dictionary-of-american-naval-aviation-squadrons-volume-2/pdfs/appen1-2.pdf

 

I wonder what series of events could lead to such discrepancy in current sources.

[stevehnz]

55 minutes ago, Marcello Rosa said:

I wonder what series of events could lead to such discrepancy in current sources.

It is a bit scary when a publication such as that is found to be flawed. A recurring theme in discussions here on BM is the seemingly perpetual propagation of inaccuracies through the decades by being repeated in print publications & even more so of late in online sources, without anyone stopping to check the integrity of these supposed facts. This is one thing that I really rate the discussions on here for, they may be convoluted at times, get a bit heated even but generally arrive at something that can, as far as is possible, be accepted as fact.

Steve.

[Marcello Rosa]

A little update on this one. This weekend we just had the first Australian Model Expo since the beginning of the pandemic. This was my first opportunity to show my models in public and compete. And the news is..."Redwing" got first prize in the small scale/ propeller planes (Out of the Box) category! 

 

[Dermo245]

As a fan of older kits, that's stunning work Marcello 

Love it.

 

Congrats on your award too.

All the best,
Dermot

[MACALAIN]

On 27/06/2021 at 04:55, Marcello Rosa said:

I attach here photos of my recently completed Privateer, built out of the box (+ some home made improvisations) from an original Matchbox kit that has sat in the box for 40 years. The problems with this kit are well known, and as expected this was a troublesome build (if you want to know details, visit my personal webpage; link in my signature panel). Still, I really wanted to build a Privateer, the idea of converting a B-24 kit was just too daunting, and I found it for a bargain in eBay (currently these kits are going for more than $200 AUD - more than 3 times my investment...). 

 

Surprisingly, the decals performed like champs, even I opened the box though they were all warped, yellowed and stuck to the flimsy paper that was supposed to "protect" them. In fact, it was nothing that 8 weeks of exposure to sunlight could not cure. I also stuck with the original engine cowlings, even though sampling the internet would make you think these are gross abominations that misrepresent the original (I honestly could not see what the fuss was all about; pretty OK for 1/72 scale). Whereas the propellers did look wrong, I did my best to make this less visible using the time-honoured technique of sanding. 

 

One irritating aspect of this build was that Tamiya cement (both the normal and the quick-setting) did not work well with the plastic: seams that I thought were long sealed tended to pop up again days later. This created multiple cycles of re-sanding, re-gluing, re-masking and re-painting, particularly along the joint between halves of the fuselage, and half-wings. I am not sure what the solution is, but if you are lucky enough to find one of these to build (they have been out of production for a while), it may be useful to try a different type of cement. 

 

Anyway, this seems to be the only kit of the PB4Y-2 around, so if you (like me) really like this plane, it is worth investing the time and effort. There were a few things I would do differently if given another chance, but I think it makes a fine addition to my collection.

 

Well done.

 

Alain

[Wulfman]

A magical Matchbox memory !

 

Wulfman

[TheyJammedKenny!]

Well done!  Bravo.

[Convair]

What an amazing model, congratulations. Thanks for using a mirror to show the underside of the kit. It's what I like to see!

[David H]

I too was just paging thru my copy of the Nicholas Veronico book, but for a different reason.

 

Looking at the three-view illustration, i was taken aback by the lack of wing dihedral. It's reproduced in the Ginter book from what looks like a Navy General arrangement drawing, so i guess its accurate.

 

The Navy drawing suggests maybe one degree of dihedral, if that. The drawing posted above shows the wing upper surfaces perfectly flat.

 

Who knew??

[Navy Bird]

3 hours ago, David H said:

The Navy drawing suggests maybe one degree of dihedral, if that. The drawing posted above shows the wing upper surfaces perfectly flat.

 

I don't think dihedral is measured at the top surface of the wing. When I built this kit, I opened up the holes for the wing tabs so that the inner surface of the wing would butt up against the wall of the fuselage that is inside the wing "cut-out." This resulted in one or one and a half degrees of dihedral (looking along the centreline of the wing leading edge). Is that right? No clue, as I could not find it specified anywhere. It seems to match my Revell PB4Y-1 if that means anything.

 

Cheers,

Bill

[Tailspin Turtle]

3 hours ago, Navy Bird said:

 

I don't think dihedral is measured at the top surface of the wing. When I built this kit, I opened up the holes for the wing tabs so that the inner surface of the wing would butt up against the wall of the fuselage that is inside the wing "cut-out." This resulted in one or one and a half degrees of dihedral (looking along the centreline of the wing leading edge). Is that right? No clue, as I could not find it specified anywhere. It seems to match my Revell PB4Y-1 if that means anything.

 

Cheers,

Bill

Page 68 of the Ginter PB4Y-2 monograph lists the “leading edge dihedral” as 3.4°. From an aerodynamicist’s standpoint, it is definitely not the upper surface of the wing. Since the depth of the PB4Y wing tapers with distance from centerline, the top of the wing will be at less of an angle than 3.4° and the bottom, more of an angle. However, since the wing is at an incidence to the fuselage of 3° and the leading edge sweeps back at 3.5°, in an accurately drawn front view, the dihedral will appear to be less than 3.4°. With significant incidence and sweep, a wing that an aerodynamicist would consider to have 0° dihedral might even appear to have anhedral. Also see Https://tailspintopics.blogspot.com/2014/03/anhedraldihedral-and-wing-sweep.html

[Darwinism]

Great work Marcello Rosa and surprisingly racy nose art for OOB!

 

I find the same difficulty with Tamiya cements vs certain European kits, so much so that I think long and hard before ordering anything from Revell Germany for instance. 

Edited June 23, 2022 by Darwinism

[Marcello Rosa]

5 hours ago, Darwinism said:

Great work Marcello Rosa and surprisingly racy nose art for OOB!

 

I find the same difficulty with Tamiya cements vs certain European kits, so much so that I think long and hard before ordering anything from Revell Germany for instance. 

Fortunately this kit was from the time I was a teenager, so the censoring of nose art had not started. The biggest surprise for me was how well the decals worked, even after >30 years. Whoever printed them for Matchbox, great job! Totally different experience with my Hasegawa PV2-7 Neptune, where the decals basically fragmented into a hundred pieces as soon I tried to pull them into place.

 

 

 

[Navy Bird]

16 hours ago, Tailspin Turtle said:

Page 68 of the Ginter PB4Y-2 monograph lists the “leading edge dihedral” as 3.4°. From an aerodynamicist’s standpoint, it is definitely not the upper surface of the wing. Since the depth of the PB4Y wing tapers with distance from centerline, the top of the wing will be at less of an angle than 3.4° and the bottom, more of an angle. However, since the wing is at an incidence to the fuselage of 3° and the leading edge sweeps back at 3.5°, in an accurately drawn front view, the dihedral will appear to be less than 3.4°. With significant incidence and sweep, a wing that an aerodynamicist would consider to have 0° dihedral might even appear to have anhedral. Also see Https://tailspintopics.blogspot.com/2014/03/anhedraldihedral-and-wing-sweep.html

 

Thanks Tommy. My "eyeball" estimate on my model was just that - now I want to go back and figure out how to measure it for real. I'm curious, even though at this stage there really isn't anything I could do if it's wrong.   

 

Cheers,

Bill

[Warwolf]

Great result from an old kit!

[Tailspin Turtle]

20 hours ago, Navy Bird said:

 

Thanks Tommy. My "eyeball" estimate on my model was just that - now I want to go back and figure out how to measure it for real. I'm curious, even though at this stage there really isn't anything I could do if it's wrong.   

 

Cheers,

Bill

Personally, I think you should fall back on TLAR. However, if you want to refine that a bit, try looking at the wing directly head on, in other words with the fuselage slightly nose down. I'll be back in a bit with a estimate of the slope of the upper wing surface from that standpoint.