Blohm & Voss P.111

[PR19_Kit]

This will be the first GB I've ever entered on here, or anywhere else for that matter, so quite looking forward to it.

Thanks for some inspired links from Tophe, and much encouragement from him too, I'm working on the asymmetric fore-runner to the Bv 138 twin boom flying boat, the Bv P.111. Various others have built models of this bizarre looking contraption before but to  my mind they've stayed too close to the Bv 138 itself, and the best looking sketch of the project had a much different fuselage to the production aircraft, as seen below. This sketch apparently came from a Polish language book on the Bv138 but I can't find a copy of it and I doubt I'd be able to read it anyway. 

I spent some time drawing up some plans from the sketch, and it was NOT an easy task either, taking many evenings and taxing my PaintShoPro skills somewhat. Then comparing the drawing with my recently obtained Revell Bv 138 kit I saw I'd need some more bits and pieces, not the least an undercarriage, as my rational for the deeper fuselage concerns it making space for some wheels to make it into an amphibian. 

The phrase 'cutting off more than you can chew' comes to mind, but if there wasn't a challenge it wouldn't be as much fun, right?

The drawings and the bits of the kit show how much I'll need to work on it (translates as a LOT!!!) and I'll need a donor Catalina for the wheels and the wing extension but that's en route, and after I get back from a short break next week I'll start cutting plastic.

More reports as they come to me.

[Slerski]

Will she have X-tended wings ? 

[Mossie]

Wow, quite a project here Kit, looking forward to seeing the result!

[PR19_Kit]

Will she have X-tended wings ? 

Actually yes, comparing the plan with the plastic reveals a shortfall, so the Catalina is slated to be the donor kit for the centre section as well as providing the landing gear.

Still haven't figuredout how to mount the port side outrigger though. I'm thinking of a sideways and downward extending leg mounted inside the port outrigger float.

[Tophe]

Still haven't figuredout how to mount the port side outrigger though. I'm thinking of a sideways and downward extending leg mounted inside the port outrigger float.

with a tiny wheel retracting inside the float, or else?
Anyway, congratulations for this uneasy project

[PR19_Kit]

Tophe,

Yes, I was thinking of that, but it will need to be pretty strong, it's holding up almost one of the engines on its own and the entire weight of the only boom. 

One leg of a Fairey Barracuda may work, retracting into the float strut and the wing above and outboard. And it would look REALLY weird... 

[Tophe]

Dear Kit,
I was wondering about the ditance wheel-ground. Let me explain (with the B-52 example below): when there are wheels so distant laterally, usually the airplane land on the main wheel(s) then gently bend on one side to have the extra wheel touch. Will this be the same on your amphibian P.111? This would mean:
- either there are 2 main wheels on the main fuselage, and (when standing at rest) the lateral wheel does not touch the ground (or else: the weight makes this wheel touch and the starboard main wheel does not touch anymore, or oleopneumatic-legs make all three touch with a longer leg on starboard-side fuselage then on port-side fuselage)...
- or there is a single main wheel on the main fuselage (port side according to your profile)
Otherwise, I cannot imagine the three wheels would be level: when the touch happens, the reaction shock would be lethal (crash of the starboard wing tip) if this happens on the boom light side...
(please forgive me for the seriousness in this worry, like a JMN yelling "impossible, you damned dreamer!" - oh no, this is not at all what I mean... I just would like you to find a logic and explain for everyone to enjoy this engineer wiseness all right?)

[PR19_Kit]

Tophe,

I understand what you're saying, yes, but the P.111 will have differen lateral loading issues to the B-52. On the Big Boeing the aircraft is in lateral balance most of the time, so the tip wheels only have to support the extra load of the outboard fuel when the tanks are full.

On the P.111 the aircraft isn't in balance about it's fuselage centre-line at all, because of the assymetry. The two main legs, both of which will be standard PBY-5A Catalina legs, will support the weight of the main fuselage and the starboard engine, and the port side leg will have to support the port engine and the boom, so it will need to be pretty strong, thus my choice of a Barracuda leg if possible.

In all cases the legs will have long stroke oleos so the load build-up on landing won't be too critical, and if it is too much the pilot will be court martialed after the resulting crash........ 

[jcf]

Why not retracting up into the float like the wheels on the big EDOs used on the C-47 float-plane?

[PR19_Kit]

The Bv 138 float's a tad small for a heavy duty wheel and I don't have any larger ones handy.

On the other hand I DO have a Barracuda, just remembered where it's hidden.... 

Did anyone do a buyable conversion kit for the C-47C BTW? I built one some years ago, but the floats were a pig, had to extend a pair of Aeroclubs largest by an INCH!

[PR19_Kit]

Having tidied up the plans and got all the donor kits, I've started assembly, razor sawing and score cutting, lots of each!

The poor Catalina has sacrificed its all as the fuselage is now in three parts (watch this space for a Whiiffed flying boat with Catalina blisters on a web site near you sometime....  ) and the poor old Bv-138 now looks nothing like its former self.

Before and after pics below showing the #2 engine sawn off the fuse pod, and the cockpit and nose turret cut out so they can be raised a couple of feet. Naturally they aren't raised the SAME amount, oh no, that would have been too easy for Dr. Vogt, so they are sawn apart as well as cut out of the fuse. The new fin core is glued into the extended boom assembly and awaits the skin parts to be added later in the weekend. The wing halves have been glued together but so far they are still stock so no point in showing pics of them as yet.

Meanwhile I'm trying to figure out just how to fit the very curved sided Catalina wheel-well into the very straight sided Bv-138 hull. Somehow I forsee lots of PSR in my future....... 

[sequoiaranger]

I like this proposed asymmetric Blohm-shell.

But, yes, I think you do need a much larger "outrigger" float, both for weight in the water and to house the landing gear. The original Bv-138 outrigger float did not have the additional weight to support that yours does. I also think you "need" a steering rudder to help with the asymmetric load once it touches down in the water (although you could probably use variable engine power instead). I think Joncarrfarrelly was hitting on the right idea with the C-47 on floats.

I don't think "they" make a float with a retractable wheel already in it, but that should be relatively easy to bash (take a Stuka spatted LG and just insert it until it is flush). I have several floats from various single-engined floatplanes that will forever be "extras". You are welcome to one. PM me if you are interested.

[PR19_Kit]

I agree 100%.

I'm planning on a retractable water rudder on the aft end of the main fuse, and a greatly extended outrigger float. The latter will be a hybrid of the Bv-138 and Catalina floats, joined end to end, but with the enalarged and thickened strut right at the outboard edge. That should give me the right geometry to scab the Barracuda main wheel leg into the strut, float and wing underside.

Right now trying to get the PBY-5A wheel well into the BV-138 fuse, and it's a RIGHT pain. I may have to mount it externally with blister type fairings fore and aft to have any hope of getting it to fit. If I mount it fully flush the back of the wheel well goes in deeper than half  the width of the fuselage!   

[sequoiaranger]

Another suggestion, if it isn't too late: Use the retracting central-float landing gear setup from a Grumman Duck. I put beefier wheels on my Grumman Gander

http://www.whatifmodelers.com/index.php?action=gallery;sa=view;id=2797

but the wells, etc. would undoubtedly be shallower and might fill the bill better than the massive Catalina ones.

But, since you are already deep into "asymmetry" here, why not STAGGER the PBY's wheel wells one in front of the other? When the going gets weird, the weird get going!

[PR19_Kit]

But, since you are already deep into "asymmetry" here, why not STAGGER the PBY's wheel wells one in front of the other? When the going gets weird, the weird get going!

Now THAT'S a neat idea! Just the sort of thing that Dr. Vogt would have done too. 

(Actually he'd have probably fitted different wheels to each side, spaced asymmetrically of course........  )

I'll look into that, one wheel well either side of the step may work nicely, not only that, I could glue the two wheel strut housings to each other to give the thing some added strength. Those two rear gunners don't need to go forward for their sauerkraut and bratwurst anyway.