Official FlightLine RC 1600mm P-38 Lightning Thread

[Oxotnik]

Warbird, thanks for the discussion on the elevator. I was a bit surprised the other day when I rolled inverted and my P-38 did NOT like it, so I quickly rolled out of it. Unlike Arycon's plane, mine was breaking right, until I trimmed it out. With noticeable up elevator and left aileron trim, my P-38 flies very well.

[crxmanpat]

My plane also came with the "droopy" right wing flap on the outer wing panel, and I did the best I could to massage it back to normal. However, it appears that the assembly process seems to have made this issue permanent. It's not that big a deal, it's only a slight droop, and a few clicks of trim solve the problem.

[Aros]

My P38 has a relatively drastic left bank tendency, but it was easy to determine why. I had a feeling it would do so before the maiden flight, but didn't adjust for it ahead of time to ensure that really was the cause. The right side flap surfaces are warped and cause a downward deflection, so they act a bit ailerons with left bank functionality since it's pushing the right wing upwards. I did my best to massage the surfaces and gradually bend them to as close to neutral as possible without sacrificing the integrity of the foam and wooden flap structure. It will never be flawless in terms of banking tendency, but it was less. So, after a few flights, I gradually manually adjusted the left and right aileron clevises to position the left aileron slightly down, and right aileron deflection slightly upward. I used an additional flight to see if the clevices needed to be adjusted further, and if it needed a little extra trim, I was okay using the trim on the Transmitter for the remainder needed. It's no big deal, but it's something for you to look into.

Very interesting because mine most definitely has that drastic left bank tendency...I thought I was going insane! I will take a much closer look at my flaps to see if they are indeed warped...Thanks for the tip!

You too Bob!

[Arycon]

Very interesting because mine most definitely has that drastic left bank tendency...I thought I was going insane! I will take a much closer look at my flaps to see if they are indeed warped...Thanks for the tip!

You too Bob!

So Im not the only one! How the heck did you solve this? The amount of deflection I had to put on the ailerons was way too much, considering. Id like to be able to determine what the issue is. I welcome any insight.

[mr.frankenjet]

if you look where the wing meets the boom my starboard side on the wing top is a 1mm or so lower than the boom compared to the leftt side. I cannot come up with a fix for it so just trim up with the ale, seems to do just fine. WRT cg I had to move the battery back a few mm's on my last flight to get my hatch to close ( I had cut a bit of foam forward, fit was so tight I think the pack swelled just a little and made the clearance too close). I did have to trim the ele down a bit as the cg a bit further back so she is getting closer to neutral. Did not notice any instability so likely will run here for a bit, maybe see what I can get away with as I get more flights under my belt. Since my battery only a 5k the lighter weight makes for a more forward battery position.

[BadBob]

I know there's a post in here somewhere about balancing, but I'm short of time tonite and want to get past this. I have my 2-4S, 3300mah packs all the way back as far as they will go. I have the MrRCSound board installed under the cockpit and L/G down. I had to put 6 and 3/4 oz. of weight into the aft of the center pod to get even a slight nose down angle to balance. Is this a good thing?

[OV10]

Bob,
Landing gear up and dump that extra weight(6+ oz) that you have put aft. I know of no one that requires adding weight. Your gonna end up with a tail heavy bird when the gear goes up leaving that weight in and then you'll not be a happy camper. Am rather certain that you'll find that with the gear up your nose heavy condition will go away. As an after thought, now the only possible reason that I can figure for you to do weight adds aft is because you mentioned a sound card under the cockpit so the big questions is where did you locate the speaker(s)??? Are you running it with a separate battery?? If you've got that stuff located forward of the CG then it all becomes clear as to why you need that 6+ ounces of weight aft. Just make sure to place that weight in the wheels up condition.

[Lon]

I agree with OV10. Even with consideration of sound system location. Better some nose heavy than tail. I fly with the 3600s all the way back. With the way this plane flys, you will be fine to fly nose heavy to start out, and see how it does.

[BadBob]

Bob,
Landing gear up and dump that extra weight(6+ oz) that you have put aft. I know of no one that requires adding weight. Your gonna end up with a tail heavy bird when the gear goes up leaving that weight in and then you'll not be a happy camper. Am rather certain that you'll find that with the gear up your nose heavy condition will go away. As an after thought, now the only possible reason that I can figure for you to do weight adds aft is because you mentioned a sound card under the cockpit so the big questions is where did you locate the speaker(s)??? Are you running it with a separate battery?? If you've got that stuff located forward of the CG then it all becomes clear as to why you need that 6+ ounces of weight aft. Just make sure to place that weight in the wheels up condition.

Did I miss something? I thought the gear had to be down when balancing the plane. I know a bit of elevator compensation is necessary when the gear is up, but you know I totally forgot about the speakers. They're under and just behind the motors on the bottom of the cowls. That explains it. I put them there because this is where a few others have put theirs, but I haven't heard anything about a balancing issue with them. I'm also going to try shifting the CG from 70mm to 65mm and try again. I may even move the speakers back as far as possible towards the mains wheel well. Requires another surgery, but I can move them back about 2".

[OV10]

Did I miss something? I thought the gear had to be down when balancing the plane. I know a bit of elevator compensation is necessary when the gear is up, but you know I totally forgot about the speakers. They're under and just behind the motors on the bottom of the cowls. That explains it. I put them there because this is where a few others have put theirs, but I haven't heard anything about a balancing issue with them. I'm also going to try shifting the CG from 70mm to 65mm and try again. I may even move the speakers back as far as possible towards the mains wheel well. Requires another surgery, but I can move them back about 2".

The missing practice that you're apparently not aware of is that all aircraft that have gear that swing aft(rearward) when retracted are balanced for CG in the retracted position. Balancing with gear down puts the airframe into a tail heavy position when retracted where as you probably know is not a good place to be for control.
Regarding those speakers, get them as close to the specified CG range and that will help minimize the amount of additional weight required to get the proper balance. If you need to add weight aft of the CG range then go as far back as possible on the airframe to minimize the amount of weight needed.

[Grossman56]

It's true Bob, I had to do that with the P40 as well. Those big fat tires are, all of a sudden, about three inches rearward. I'd rather be nose heavy on landing than tail heavy in flight.

Grossman56

[BadBob]

The missing practice that you're apparently not aware of is that all aircraft that have gear that swing aft(rearward) when retracted are balanced for CG in the retracted position. Balancing with gear down puts the airframe into a tail heavy position when retracted where as you probably know is not a good place to be for control.
Regarding those speakers, get them as close to the specified CG range and that will help minimize the amount of additional weight required to get the proper balance. If you need to add weight aft of the CG range then go as far back as possible on the airframe to minimize the amount of weight needed.

You're right about gear up. I've just heard so many different opinions about the subject, but gear up makes perfect sense. I rechecked the balance with gear up and found that no weight at all was needed. The pic on the left is kinda hard to tell the angle due to the bad angle I took it in, but the nose is slightly at a down angle. I even checked it upside down.

[Fast Eddie]

Been having perfect flying weather lately, photos are screen shots from Mobius action cam. Anybody have any video or photos of their P-38's with sound? Still not sure which version to install, any suggestions?
Thanks
Eddie

[BadBob]

All dressed up and ready to go!

Save

[Dewey H Lee]

TAKE HER TO THE BALL BOB. She looks great. Let us know on the Maiden.

[T-CAT]

Congrats man! Good luck on the maiden. You probably won't need any luck though ;), as this plane is easy as pie to fly and land.

[stitch]

can anyone tell me the color for the green one? i have every military green i can find and still can,t match this green.

[TiredIronGRB]

can anyone tell me the color for the green one? i have every military green i can find and still can,t match this green.

If you have a local Home Depot they do a great job matching the color in a flat acrylic sample can for $3.

[T-CAT]

I have a picture in this thread somewhere with the paint match code I got from Home Depot if you need it. Like TiredIron said, taking a nice relatively flat piece to them to scan and color match is the cheapest and simplest approach.

[Oxotnik]

If you have a local Home Depot they do a great job matching the color in a flat acrylic sample can for $3.

Suprisingly, I've had a hard time lately getting good color matches for dark greens at Home Depot. For $3.50/8-oz sample, I get color match paints for every warbird that I buy. You can't beat the price, when you compare it to a 1/2 oz bottle of Enamel model paint. Anyway, for my P-38, Ta-152, and EFlite P-47D, the color matches have all dried too dark for the dark green. The greys are fine, but dark greens are too dark. It's not awful, but noticeable.