[TC15] Lockheed Martin P38 - White Lightnin'

[1gor]

After googling about White lightning, I have recalculated and my P-38 would be 133 studs wingspan and 97 studs ling fuselage...I would probably have to hang it on ceiling 

But when I saw white version, I could not hesitate and have downloaded several wallpapers of it 

I'll probably 'steal' few your ideas in future 

[Rudivdk]

That is BIG.

I was also very much charmed by the white version, it looks great on the plane I think. Feel free to use whatever you want, I would be honored if I can be of inspiration to you

[1gor]

Thank you for permission 

I have looked at several color combinations on P-38 but white lightning is indeed best looking version. Pity that LEGO Technic cargo plane (42025) was more expensive here (in Croatia) than Arocs, so I bought Arocs...

Yes it is huge, but if I decide to build it one day, it has to fit my other mocs scale, so I could use Unimog U423 or Fastrac 4220 to pull it 

First thing I have to make 1:15 'blueprint" of P-38, but here only this costs some 30€ (what is not cheap when I compare with my income which is about 850€)...

I'll see what future is planning with this project 

[Rudivdk]

7 minutes ago, I_Igor said:

I could use Unimog U423 or Fastrac 4220 to pull it 

That would quite a sight

7 minutes ago, I_Igor said:

I have to make 1:15 'blueprint" of P-38

You do take this seriously, I created my version without any scaling reference, just eyeballing it... If I would recalculate my version, I think it would be way off, but that is just the way I build

[1gor]

All my models should represent correct proportions and characteristical design and features of real thing (of course I do not expect that P-38 flies), but to look as close to original and have flying commands that corresponds original

[steph77]

Hi Igor.

You didn't choose the easy way with this model, as all commands and links are separate from the main cockpit area.

This is why (the not easy way choice) I think your model is one of the more promising one. Have fun on it!

[1gor]

On 12/9/2018 at 4:35 PM, steph77 said:

Hi Igor.

You didn't choose the easy way with this model, as all commands and links are separate from the main cockpit area.

This is why (the not easy way choice) I think your model is one of the more promising one. Have fun on it!

I'll have fun (some day in future); thank you very much for that, but currently I'll keep my feet on the ground (working on Fastrac currently). I wanted always to make one of airplanes like P-38 or Focke Wulf FW189...anyway there are few interesting models in development here in TC15 

About commands you are completely right, but I think I have what I need in following images:

https://conceptbunny.com/wp-content/uploads/2017/10/Lockheed_P-38_Lightning.gif

And

https://conceptbunny.com/wp-content/uploads/2017/10/lockheed-p-38-lighting.jpg

(Images are to big, so I have posted links instead)

Edited December 28, 2018 by I_Igor
I really hate that autocorrect...

[Rudivdk]

Quick update:

Did not get as much building time as I hoped over the last week, but still got a lot done.

Working my way from the outside in now. Tails and wings are nearly done, with all control surfaces in them.

PF motors and rechargeable battery are installed and nicely hidden. Prop is driven by a motor. Can anyone spot the PF?

Now I have to find a way to connect all of it to the center cockpit control stick... And I have to fit landing gear + controls, flaps controls and prop blade pitch control. And get my weight distribution correct so the plane will actually stand on its wheels. And make sure the structure is solid enough to prevent too much bending...

Ah well, I still have a few weeks left...

[Seasider]

PF hidden just where the boom/fuselages join the central structure? One either side towards the rear.

loving the build so far

[1gor]

1 minute ago, Seasider said:

PF hidden just where the boom/fuselages join the central structure? One either side towards the rear.

loving the build so far

You beat me , I think it is just in front of cockpit.

It looks very nice 

Edited December 16, 2018 by I_Igor

[kodlovag]

Oh, this plane is huge. I think you can easily fit all the mechanism into it.

[Rudivdk]

39 minutes ago, I_Igor said:

I think it is just in front of cockpit.

Jackpot, the batterybox is in front of the cockpit. Directly right of the cockpit on the front of the center wing piece is a PF switch (you can just see the 3l axle sticking out of the switch), which connects the motor to the BB. The motors are at the position of where the real engines would be, at the front of both fuselages just behind the prop (under the black and white panels), I had to mount them as much to the front as possible to get some counterweight to compensate the long tails. Might still not be enough...

The motors will each drive 1 prop, and a secondary forward/reverse gearbox, 1 for landing gear and 1 for flaps. Gearboxes are mounted left and right of the cockpit in the center wing pieces.

[grum64]

This is one big build. Watching with interest 

[BrickbyBrickTechnic]

Awesome job with this plane. The PF is very well hidden.

[Tommy Styrvoky]

Maybe if possible to introduce more functionality, the vents for the radiators on the P-38 can be articulated to control temperature. 

Edited December 17, 2018 by Tommy Styrvoky

[1gor]

This doors usually are used to "pull out" the heat that is accumulated at supercharger area (supercharger is just in front of them) 

[Rudivdk]

7 hours ago, Tommy Styrvoky said:

Maybe if possible to introduce more functionality, the vents for the radiators on the P-38 can be articulated to control temperature. 

I would love to do that, it's indeed a distinctive feature, but I set myself a goal to have all functions be controlled from within the cockpit. I am already struggling on how to fit all current functions, let alone implement yet another function in there....

Will keep it in mind though, might be doable if I make that controllable from the top of the fuselage or the center wing piece or something like that.

[Rudivdk]

Another update:

Mainly working on the 'insides' of the plane now.

I've added landing gear and motorized it, with an up/down gearbox with control switch in the cockpit. I have 1 really big issue now... the plane is very tail heavy and does not stay on it's wheels. So for now I added a display stand... Will have to see what I can do later to minimize weight on the tails, but I do not think I can shave of a lot there. I already added some boat weights to the front, but it's nowhere near enough...

Front wheel mechanism: 

This was a particularly difficult one to create, as I have my PF batterybox sitting between the gearbox and the front wheel. I only had the tip of the nose to house some mechanism, but the final solution works like a charm and is really compact. It's not very visible in above picture, I will make a 3D render of it later.

Rear wheel (only one wheel connected to gearbox right now):

In above pics you can also see flaps assembly: 4 flaps in total, 2 on center wing and 1 on both outside wings. They will be motorized as well, and controlled by another up/down gearbox on the other side of the cockpit:

All the black/dbg levers and links running under the gearboxes are coming from the 3-axis control stick. Ailerons and elevator are already connected, rudder still to be done, but I've designed it so just need to build it.

Aileron control mechanism detail:

Edited December 28, 2018 by Rudivdk

[1gor]

So far as I can see your commands look very promising. About weight distribution I have one rather stupid question - is it rear to heavy when you put rechargeable batteries in battery box?

(Where I live rechargeable are significantly heavier than non-rechargeable)

[Rudivdk]

Just now, I_Igor said:

So far as I can see your commands look very promising. About weight distribution I have one rather stupid question - is it rear to heavy when you put rechargeable batteries in battery box?

(Where I live rechargeable are significantly heavier than non-rechargeable)

Well, I only have the rechargeable lythium BB, so I can't put batteries in it... It would probably help though...

[pleegwat]

Is the position of the rear wheels based on the reference, or can it be moved further back? Even a little bit may matter a lot.

Alternatively, lengthening the wings might help? Again not sure what your reference allows.

[Rudivdk]

Just now, pleegwat said:

Is the position of the rear wheels based on the reference, or can it be moved further back? Even a little bit may matter a lot.

Alternatively, lengthening the wings might help? Again not sure what your reference allows.

I didn't measure it, but on the real P38 the rear wheels are in similar position, slightly behind the center of the wings. Since they retract backwards, moving them towards the rear will cause a redesign to parts of the tail section as well. But I already checked the current COG, it is only 3 to 4 studs backwards so it should be possible and not too far out of scale. Then again, it would probably interfere with the flaps control axle... I will first try to finish the plane as it is, I still have to add some panelling to the front and some more details, so after that is done I know how much weight or wheel redesign is needed. Worst case I can always flip the rear wheels around, making them extend backwards and thus putting them far behind COG.

[BrickbyBrickTechnic]

This project is one of my favorites so far. I'm sad to hear about the weight problems (I have never faced those myself, so I'm not sure where to start in terms of input) but I wish you luck and hope you get it done on time.

This project shows lots of mechanical ingeniosity and space management. Keep it up!

[1gor]

10 hours ago, Rudivdk said:

Well, I only have the rechargeable lythium BB, so I can't put batteries in it... It would probably help though...

And I can not afford my self smaller rechargeable battery box so everything has it's advantages and disadvantages...

For classic Technic battery box is not enough space...remember when I mentioned 1:15 scale; that is one of reason - size of battery box

[pagicence]

Maybe you can stick something or some more pieces underneath the wings to move the center of gravity forward.