Official FlightLine RC 1600mm P-38 Lightning Thread

[Larry D]

Just hoping that someone at MRC will see this. Lately Flightline/Freewing have been pre-applying decal sets and the customer has no choice but to accept it. Yeah, I know, it can be repainted, but then there is the masking, color match, etc. As a long time customer and firm believer in the overall quality of Flightline and Freewing products, PLEASE at least offer customers the opportunity to select the decal set they desire. Looks like I'll be repainting a new out of the box airplane. SIGH

[flyguysc1]

motors run all surface controls work both esc s calibrated one still beeps repeatedly.pull battery connecter on one esc beeping still precise

[GliderGuy]

motors run all surface controls work both esc s calibrated one still beeps repeatedly.pull battery connecter on one esc beeping still precise

Continuous beeping can be an indicator that the throttle transmitter channel is reversed from what is needed.
Try reversing the direction of the throttle channel in the transmitter.

CAUTION!!! You should remove the props when you are experimenting with the ESCs. If she comes alive at full throttle on the workbench, you can get seriously injured.

-GG

[Captain Billy]

I put the maiden flight on a friends Flightline P-38 and took his word that the plane was correctly balanced. I had to put all of the up trim in the transmitter to get the nose up and still had to fly with about 1/4 stick of up elevator. Just about had nothing left to lift the nose on landing. From what he told me, the instructions say to balance the aircraft 65 mm from the leading edge at the root of the wing. Can anyone confirm that the aircraft flies well at this balance point or does the CG need to be somewhat farther back. Just trying to see what experience you guys may have had with the airplane.

[RCAVI8T0R]

I put the maiden flight on a friends Flightline P-38 and took his word that the plane was correctly balanced. I had to put all of the up trim in the transmitter to get the nose up and still had to fly with about 1/4 stick of up elevator. Just about had nothing left to lift the nose on landing. From what he told me, the instructions say to balance the aircraft 65 mm from the leading edge at the root of the wing. Can anyone confirm that the aircraft flies well at this balance point or does the CG need to be somewhat farther back. Just trying to see what experience you guys may have had with the airplane.

I have flown at the book CG (65mm) for years with no issues. I do have some up mechanically adjusted up elevator when the sticks are relaxed.

[Evan D]

I think the problem with the book CG is the reference point for the 65mm. In the end book CG is a starting point. Move to suit.

[Grossman56]

Just wondering if the elevator was level when the trim was neutral, it might be a case of improper setup...
Doesn't take much down elevator to throw things off.

Grossman56
(Dangerous Dan)

[GliderGuy]

The set-up manual shows 4 mm of up elevator setting with neutral stick and with book CG (see excerpt screen capture).
Also, she pitches up when flaps are lowered, so per the book…mix in a bit of down elevator as the flaps are lowered…flaps = master, Elevator = slave

If the mechanical 4 mm up elevator isn’t set, you’ll have your hands full keeping the nose up on the maiden. Book CG is fine for starters.

-GG

[rckruser]

P-38 Motor Mount Replacement
How do you replace a broken motor mount? Do you have to completely cut off part of the nacelle? If so, in front of the mount or behind it? Could you cut part of the nacelle and pull the mount out and slide a new one in?
I had the port motor prop blow a blade in flight. Only damaged the LG doors and the motor mount. It twisted in place and broke.

Thanks in advance,

Bernie

[xviper]

P-38 Motor Mount Replacement
How do you replace a broken motor mount? Do you have to completely cut off part of the nacelle? If so, in front of the mount or behind it? Could you cut part of the nacelle and pull the mount out and slide a new one in?
I had the port motor prop blow a blade in flight. Only damaged the LG doors and the motor mount. It twisted in place and broke.

Thanks in advance,

Bernie

Are you talking about the "X" mount that is screwed onto the back of the motor and then that whole thing is screwed to the firewall (aka "motor board")? This is what Freewing calls the "motor mount":

https://www.motionrc.com/products/flightline-motor-mount-type-a-mo1364842?variant=

You remove the spinner and whatever is left of your prop. The yellow part is held on by a couple of screws. Then the whole yellow cowl comes off. The X-mount is pretty obvious.

Or are you talking about the "motor board"?

https://www.motionrc.com/products/flightline-1600mm-p-38l-motor-board-flw301092?variant=

This one is a little more complicated. Looking at the cut-out drawing in the owner manual, you can see that the motor board is held in place by the foam in front of it (page 9). If it were me, I'd cut the whole front section (foam part) of the engine nacelle, immediately in front of the motor board. Remove the motor and X-mount first. This way, you have the most amount of surface area of foam to glue back onto the nacelle. Once you've done that, the motor board should come right out by pulling it straight forward. When you put the new one in, glue the back of it to whatever is behind it. I haven't had my P-38 for quite some time and never had to do this on the plane but I have done something similar to an FMS Corsair. The other simple option is to buy a complete left or right fuselage. It'll come with the motor board already installed.

BTW, have a look at this picture from an earlier post. It may give you some ideas:



And take a look at this post:

https://www.hobbysquawk.com/forum/rc-airplanes/rc-propeller-airplanes/1978-official-flightline-rc-1600mm-p-38-lightning-thread?p=141753#post141753

[rckruser]

Are you talking about the "X" mount that is screwed onto the back of the motor and then that whole thing is screwed to the firewall (aka "motor board")? This is what Freewing calls the "motor mount":

https://www.motionrc.com/products/flightline-motor-mount-type-a-mo1364842?variant=

You remove the spinner and whatever is left of your prop. The yellow part is held on by a couple of screws. Then the whole yellow cowl comes off. The X-mount is pretty obvious.

Or are you talking about the "motor board"?

https://www.motionrc.com/products/flightline-1600mm-p-38l-motor-board-flw301092?variant=

This one is a little more complicated. Looking at the cut-out drawing in the owner manual, you can see that the motor board is held in place by the foam in front of it (page 9). If it were me, I'd cut the whole front section (foam part) of the engine nacelle, immediately in front of the motor board. Remove the motor and X-mount first. This way, you have the most amount of surface area of foam to glue back onto the nacelle. Once you've done that, the motor board should come right out by pulling it straight forward. When you put the new one in, glue the back of it to whatever is behind it. I haven't had my P-38 for quite some time and never had to do this on the plane but I have done something similar to an FMS Corsair. The other simple option is to buy a complete left or right fuselage. It'll come with the motor board already installed.

BTW, have a look at this picture from an earlier post. It may give you some ideas:



And take a look at this post:
https://www.hobbysquawk.com/forum/rc...753#post141753

Thanks for the prompt reply. Yes it is the "motor board" that broke. You confirmed my fear that I will have to cut the nacelle. I was thinking of cutting a 1/2 inch wide piece on the top of the nacelle with the motor board centered in the foam cutout. I should then be able to lift the board out and slide the new one in. This way I don't have to cut the whole front of the nacelle off. Do you think this will work? I was planning on using Foam Tac to reattach the piece(s). I will probably add the bamboo skewers to prevent the board from twisting.

Thanks again X.

Bernie

[xviper]

Thanks for the prompt reply. Yes it is the "motor board" that broke. You confirmed my fear that I will have to cut the nacelle. I was thinking of cutting a 1/2 inch wide piece on the top of the nacelle with the motor board centered in the foam cutout. I should then be able to lift the board out and slide the new one in. This way I don't have to cut the whole front of the nacelle off. Do you think this will work? I was planning on using Foam Tac to reattach the piece(s). I will probably add the bamboo skewers to prevent the board from twisting.

Thanks again X.

Bernie

That seems like an even better idea than mine. Your idea would maintain more of the fore/aft integrity of the motor board once you've got it all back together. FoamTac would also be my first choice for glue.
My second choice on how to do this would have been to cut the front area along the seam, top and bottom. Then split the 2 halves until you could pull out the board. This is what I had to do with my FMS Corsair.

[rckruser]

That seems like an even better idea than mine. Your idea would maintain more of the fore/aft integrity of the motor board once you've got it all back together. FoamTac would also be my first choice for glue.
My second choice on how to do this would have been to cut the front area along the seam, top and bottom. Then split the 2 halves until you could pull out the board. This is what I had to do with my FMS Corsair.

I'm seriously going to consider your split the seam option. There's a lot more foam in there then I first thought. The foam covers most of the back (as well as the front) of the board. There is only about 4.5 inches on the top and 8 inches on the bottom of the nacelle that needs to be split. I'll need an extra long X Acto blade LOL.

I have a FL Sea Fury fuselage with a broken board. After struggling with it I simply replaced the fuse. I still have the old one and I'm thinking about trying the two theories on it. A little surgical practice. While the construction of the planes are different I think this will give me a clue to the best approach.

With the season quickly shutting down it may be a few days (weeks) before the surgery. I'll let you know the results.

Thanks again,

Bernie

[Couchbr]

Just out of curiosity, has anyone tried using the FL B-25 motors and ESC’s in the P-38? I’m not looking for an increase in speed, but increased flight time off of a single battery.

On paper it looks doable. Both planes use 3748 outrunners so you don’t have to worry about spacing. Just the KV is different. They also use the same prop size so you can keep the stock props. It looks like you can just switch out the motors and ESC’s and have a P-38 running off of 1 6S battery just like the B-25.

But, what would she be like in the air? You would have the B-25’s power in a lighter and more aerodynamic airframe. Sounds like fun to me.

[Elbee]

Couchbr

Welcome to Hobby Squawk or at least thanks for your first post.

Glad to have you onboard, Sir.

Unfortunately, I do not have an answer, but if I may refer you to Grossman56, he might be able to assist.

Dan, If you would/could, can you help with this question?

I figure between you and davegee you might have an educated guesstimate.

Respectfully, LB

[xviper]

Just out of curiosity, has anyone tried using the FL B-25 motors and ESC’s in the P-38? I’m not looking for an increase in speed, but increased flight time off of a single battery.

On paper it looks doable. Both planes use 3748 outrunners so you don’t have to worry about spacing. Just the KV is different. They also use the same prop size so you can keep the stock props. It looks like you can just switch out the motors and ESC’s and have a P-38 running off of 1 6S battery just like the B-25.

But, what would she be like in the air? You would have the B-25’s power in a lighter and more aerodynamic airframe. Sounds like fun to me.

I can't say what it would be like to put the B-25 power system into the P-38, but I have put the B-25 motors into my Nexa (aka:
VQ") Twin Otter (with floats). (I also have the Flightline B-25. That's how I got the idea.) However, on my Twin Otter, I run the 5-blade scimitar props from the Eflite EC-1500. These give way more torque (and pull). Total weight is over 3.5kg without battery. With this set up, the T.O. is very spritely.

As for putting this power system into the P-38, here's my analysis and opinion. (P.S. I used to also have the FL P-38 and it could have benefitted from the B-25 motors). The B-25 system would give you a max rpm of about 1000 rpm more than what your stock P-38 would put out. Keeping the same prop, the P-38 on 6s would feel about 10% stronger. This could translate into a bit more speed and "get up and go". However, since you mentioned flight time, I doubt you will achieve a whole lot more in that parameter. Comparison: On 4s, each motor is running on 3000mah of juice. On a 5.0A, 6s, each motor would run on about 2500mah of juice, but because it's got more ooomph, you may fly at less throttle to achieve similar flying characteristics, so this may even out. The 6s system would also spool up a lot quicker, making the P-38 seem a lot more powerful. As they say (don't know who "they" might be), if you've got the power, you'll tend to use it, so you can draw your own conclusions.

[rckruser]

Just out of curiosity, has anyone tried using the FL B-25 motors and ESC’s in the P-38? I’m not looking for an increase in speed, but increased flight time off of a single battery.

On paper it looks doable. Both planes use 3748 outrunners so you don’t have to worry about spacing. Just the KV is different. They also use the same prop size so you can keep the stock props. It looks like you can just switch out the motors and ESC’s and have a P-38 running off of 1 6S battery just like the B-25.

But, what would she be like in the air? You would have the B-25’s power in a lighter and more aerodynamic airframe. Sounds like fun to me.

I see that you are not in it for the speed. FWIW I fly with another flyer with a B-25 on 6 cell. He outruns me easily when the P-38 is on 4 cell. That being said, I have flown at least ten flights with a Admiral 5 cell 4000maH on the stock setup. It is comparable to the B-25, maybe even a little faster. Would I recommend a 5 cell in the P-38 with the stock motor/ESC. NO!! My bench static test shows 64amp on the ESC at 3.84V/cell. Definitely over the limit of the stock 60A ESC.

Your post prompted me to see if a 6 cell would even fit. It is a small battery bay. The only 6 cell battery I have is a SMC 6000maH. It barely fits. I had to put it as far back as it would go. I did not measure the CG, but it seemed tail heavy to me. Before making any power system changes, check to see that your 6 cell fits and the CG is not affected.

As xviper indicated, I don't think you will see extended flight times with a 6 cell. I fly 2 4 cell 3000maH Admirals and get a easy 8 minutes on mixed throttle flying.

Bernie

[xviper]

I think the P-38 could fit a 4000mah (or less) 6s battery. A 5000mah, 6s might also fit but the CG might be hard to achieve.

[GliderGuy]

Adding my 2 cents.... I use two of the Admiral 4S 3000 mAh 35C batteries. Timer is set for 5 minutes, and at about 75% throttle most of the flight plus some full throttle hot rodding, I consistently land with 1300 mAh consumed (as shown on the charger...next charge cycle). This leaves me with 1700 mAh remaining in each battery (of course...that'd be an unrealistic 100% drain to use that much). So, definitely more than 5 minutes is possible, and this bird is a spirited performer on stock power.

Why mess with a successful stock set-up?

-GG

[xviper]

Why mess with a successful stock set-up?

-GG

I agree! If his goal is to simplify the battery set up to use just one battery, it's easy enough to modify the wiring to accept a single 4s battery of the appropriate size. It's not a single battery that gives more flight time. It's more that it's what size of single battery will give more flight time and what size will fit in the space available and not make achieving the correct CG difficult.