Mighty "Mini" PBY-5A Catalina - WWII Flying Boat

localfiend

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I've had this in mind ever since I saw that Flitetest may be coming out with waterproof foamboard. If that actually happens, it'l be great, however, in the meantime I think this can be easily done with dollar tree foam as well with some simple waterproofing methods. Since I'm still watching paint dry on some of my other builds I started on this.








I called this plane a Mighty "Mini" as it uses the MM swappable pods (designed around the F pack), though it's not really so Mini. The planned wingspan is 57 inches. Smallest you can go and have the pod/cowl setup stay scale.

If all goes as planned, this won't be a difficult build, you'll just need to take your time on the parts that need to be sealed. Flight characteristics should be very gentle. With anticipated wing loading, this should fly like a high wing trainer, which will be great for learning how to land and take off from water.

This plane should be able to take off and land from water, grass, snow, then with the addition of wheels, dirt and pavement. Truly all terrain. I'm also hoping it will be able to carry significant payload, which will be great for simulated bombing runs / candy drops etc...

I'm still playing with fuselage designs, and haven't yet decided if I want the wing to be easily removable or not. Here's a preview of where I'm at:



Lower half of Hull, this will be completely sealed:





Tail section will glue to the top/back of this, and there will be formers and such for the top half of the fuse. I plan on making the printable clear canopies and weapon blisters like usual.



Messing with tail designs. Think I'm going to use the one from WWII with the split elevator.



Wing prototype (Final will have cutouts for the MM power pods and cowls):



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Most Current Beta Plans:

b0Ol5Wg.jpg


Mighty Mini PBY Catalina Beta v.2 - Tiled

Mighty Mini PBY Catalina Beta v.2 - Full

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Giant version built at FF East 2016. Flies just like the small one, only its a lot bigger lol.

 
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Rasterize

Maker of skins and decals for foam board RC planes
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Oh you bad, bad man. Now I must put my life and all other projects on hold and follow this with baited breath.
Ok, so maybe I like the PBY just a little and maybe my dad was a crew member on a PBY out of Corpus Christi Texas during WW2.
 

flyingsquirrelRC

Senior Member
lol asked for this design before.

glad to see it. "might" have to try it ;)

(see what I did there -> "might" as in "might - y mini")

Yeah that was really bad never mind....
 

earthsciteach

Moderator
Moderator
You, sir, have my attention. This is one of my all-time favorite airplanes and you are making DTFB look damned good.

Word is that the water-resistant foam board will be available, "soon."
 

localfiend

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Thanks everybody. Didn't realize the PBY was such a popular plane. Hopfully the DTF version will live up to expectations.

Oh you bad, bad man. Now I must put my life and all other projects on hold and follow this with baited breath.
Ok, so maybe I like the PBY just a little and maybe my dad was a crew member on a PBY out of Corpus Christi Texas during WW2.

Cool, that's a much better reason to be obsessed with the PBY than the excuse I have. My fascination started after reading Into the Storm. It's a book about a WWII destroyer and a PBY that get sent way back in time and fight dinosaurs. :eek: Yeah, I'm a nerd.


You, sir, have my attention. This is one of my all-time favorite airplanes and you are making DTFB look damned good.

Word is that the water-resistant foam board will be available, "soon."

Excellent. Paper on foamboard that starts out water resistant will be great for these kinds of projects.
 

localfiend

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Man, how do you cranks these out so fast?

Easy, a deep abiding hatred for the stack of foam-board sitting in the corner. It must be vanquished!

Actually, I'm down to 4 sheets. Gonna need to make a dollar tree run.

The secret to coming out with lots of designs is to not finish them... I have a bunch of projects still awaiting final touches. :D


I'm wondering if I should make the wing tip floats retractable. I think it can be done quite easily with some popsicle sticks, BBQ skewers, and a 9 gram servo. Maybe I'll do two wing designs.

The one I have right now has an exaggerated amount of dihedral (partly by accident). A trainer wing, and a scale/sport wing with retractable floats would simplify things.
 

localfiend

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Been keeping a build log as I test fit parts. Hopefully what I've done so far won't change too much, so I'm uploading pics of the build.

Everything I'm showing here is without packing tape as I plan to try and seal the lower hull using only water based Min Wax Polycrylic. Polycrylic is great, and hot glue still sticks to it.

If you don't want to use minwax, then the packing tape method can be used (worked great on my A6M Zero Floats). It's easiest to cover one side of a piece of foamboard entirely with a layer of tape. When your foamboard is taped, you can then cut out your parts. Doing it this way makes the build very clean looking, and does an excellent job of keeping out the water if you seal all edges well with hot glue.

Ok...

Remove all the paper as called for on the plans, make your bevel cuts, then glue in the bottom former:

9oxCExp.png


Pre-bend the bottom plates on the lower hull:

eSzYXhk.png


The foam should compress nicely:

j5ArV6I.png


This is a pretty standard B fold like you would do on most fuselages, it's just not 90 degrees. Add glue and fold the sides up against the former angle one side at a time.

DJWuxNK.png


Use tape to hold the side plates in place:

bW3L8N0.png


dZCLe5A.png


A little bit at a time is easiest.

xRZv3ZD.png


dTXcpm2.png



Do both sides, then go ahead and attach the little rear pieces with some tape as well.

GcEAH6A.png


Now start joining the bottom pieces of the hull the same way you did the sides:

TpXOKs6.png


When you're done this is what it will look like from the back. There will be a gap.
2HwDWR4.png


The next bottom piece will fit into that gap (the finalized piece won't have quite so much extra paper around the edges....

You might not be able to see it, but I went of the edge that fits into the gap with a marker to flatten it a bit.

7WoFt0o.png


Stuck in the slot:

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View from the bottom:

aaw7vZS.png


Glued in place and excess paper trimmed off:

6OhaysV.png


Side View:

8MTYMDp.png


Weight check:

02rC6Z2.png


Not too bad. That's as far as I've gotten. Gonna go test fit the next bottom pieces and get to work on the tail.
 
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localfiend

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Yay! Seaplane! Will you be making your's sea worthy? I'd love take one of these off the water.

Yep. Shouldn't take too much to make it ready for water so that's the plan. The build uses the same build and waterproofing concepts I used for my A6M Zero floats, and those survived a night floating in a bathtub with no I'll effects.