The Martin PB3M-1 Master Mariner

[zenrat]

...That sounds like a winner to me, thanks VERY much. 

You'd have come up with it soon enough.


Could you duct cooling air in through the weapons bay?

[Captain Canada]

Nice start ! I always forego all of the fiddly bits lol

[Old Wombat]

Ah, I think I've solved the prop rotation problem.

Having re-read my SM-77 thread, I didn't fit reverse rotation Merlins to it, they had an extra idler gear added to the prop gearbox, like the starboard engines on a Hornet. So I'm sure Wright could do the same job on the rear engines of the PB3M-1. 

The cooling issue still remains though.

Could you just fit the cowlings (backwards) & keep the cooling flaps as variable ducts? Maybe with a fan (similar to the BMW 801 radial of the FW190) to draw air out over the engine?

[Steel Penguin]

or have the flaps open and claim that it adds thrust, due to the air RAMing in and then having energy added due to cooling the engine and going out the back as a sort of jet / rocket exhaust,  sort of like the oil cooler on the Mustang.

[McColm]

Additional cooling ducts on the cowlings.

[tahsin]

Regular radial engine upfront,
FW-190 prototype style spinners for the pusher engine where the heated air leaves from the center.

[PR19_Kit]

You'd have come up with it soon enough.


Could you duct cooling air in through the weapons bay?

Yeah, maybe AFTER I'd finished building it another way..................

That may be possible actually, there's socking great holes on both fore and aft bulkheads of the weapons bays.

Could you just fit the cowlings (backwards) & keep the cooling flaps as variable ducts? Maybe with a fan (similar to the BMW 801 radial of the FW190) to draw air out over the engine?

I don't think so, the cowling tapers quite a bit and it's too small to fit over the rear part of the crankcase. But the Fw-190 type fan might be a good idea. 

All the other ideas have merit too, much more than I had to start with. I'll see what looks most likely when I get home next week and can check-out the Vacform Mariner in The Loft.

In the meanwhile, here's all the sub assemblies I've been working on this week.



The tail assembly's fully dine now, and fits like a charm too. Only the starboard wing (shown here on the left...) has its upper surface added because of a 'glitch' in the design. The bomb bay 'walls' are a tad too high and come up flush with the wing's upper surface, but the outer wing panel has a flange that's meant to tuck under the gull section on top of the standard Mariner wing section. But it can't as the bomb bay wall is in the way.

I'll do some styrene shaving in an attempt to sort it out.

[Rick Lowe]

Making good progress already! 

[PR19_Kit]

I'm back home now and dug out the Rareplanes vacform Mariner kit to see if it'll suit my intended mods.

It certainly does, but it'll be some work of course. Two good things are that it includes the earlier, shorter engine nacelles which will suit the pusher engines better, and it also has the proper length radome, the Academy one looks FAR too long for me.

Styrene slicing will probably commence later this evening. 

[kerick]

So cool to watch!