Official FlightLine RC 1600mm P-38 Lightning Thread

[xviper]

Don't ya love it when things finally work the way they should? :Cool: I guess they forgot to put in the addendum sheet on your model. It helps if the instructions are up to date.

[wallacems]

Has anyone converted their flightline P-38 to a solid Master Air Screw MAS 3 blade prop and if so how did you do it? size prop used, brand of spinner and size, and any mods made to the engine shaft? I lost mine a few days ago as it threw a prop when the back plate broke under high speed maneuvers and I wanted to go to a solid metal back plate and single 3 blade prop to prevent it. It is possible I may have to reinforce the plastic firewall and do bolts vice screws though. Thoughts?

[Beeg]

Has anyone converted their flightline P-38 to a solid Master Air Screw MAS 3 blade prop and if so how did you do it? size prop used, brand of spinner and size, and any mods made to the engine shaft? I lost mine a few days ago as it threw a prop when the back plate broke under high speed maneuvers and I wanted to go to a solid metal back plate and single 3 blade prop to prevent it. It is possible I may have to reinforce the plastic firewall and do bolts vice screws though. Thoughts?

I think Kougar Mark II was the first to do the MAS conversions..

https://www.rcgroups.com/forums/showthread.php?2580046-FlightLineRC-P-38L-Lightning-1600mm-%2863inch%29/page365#post35844221

[flyAA]

Has anyone converted their flightline P-38 to a solid Master Air Screw MAS 3 blade prop and if so how did you do it? size prop used, brand of spinner and size, and any mods made to the engine shaft? I lost mine a few days ago as it threw a prop when the back plate broke under high speed maneuvers and I wanted to go to a solid metal back plate and single 3 blade prop to prevent it. It is possible I may have to reinforce the plastic firewall and do bolts vice screws though. Thoughts?

I just ordered all of the stuff to convert mine to 6s. For 6s i went with 11x7x3 MAS props (1 is a rev/pusher). I think if you stay 4s 12x8x3 is recommended but I’m not positive.

Spinners is is where it gets complicated. There’s a few methods I came across
-go no spinners at all. I couldn’t do that. Too ugly
-shave off the grooves from the stock backplates and then modify the stock spinner to fit the MAS prop
-order dubro spinners (i did this)
-tru turn spinners. I’m not sure of the details
-one guy used just the stock spinners modified to fit the MAS props and didn’t use any backplates

if you go to RC groups and do a search on the p-38 thread for MAS there is a ton of stuff that pops up.

Good luck my dude

[Wolfgang Wagner]

Hey guys, I donˋt know, if this question has already been discussed, so I like to know, if it is really that important to cut/remove one of the two red ESC-power (+) wires to prevent possible interferences between the powering of both ESCs. There is a lot of discussion in the web and I am a little bit confused. The P38 has no UBEC, so I think there is one BEC in every single ESC that is powered. And that could cause interferences between both ESCs and in the end harm the electronic and Finals crash the ac. Is that correct and should I remove one of the wires?
Thanks a lot in advance

[Oxotnik]

Hey guys, I donˋt know, if this question has already been discussed, so I like to know, if it is really that important to cut/remove one of the two red ESC-power (+) wires to prevent possible interferences between the powering of both ESCs. There is a lot of discussion in the web and I am a little bit confused. The P38 has no UBEC, so I think there is one BEC in every single ESC that is powered. And that could cause interferences between both ESCs and in the end harm the electronic and Finals crash the ac. Is that correct and should I remove one of the wires?
Thanks a lot in advance

There has been a good bit of discussion on this topic. I don’t remember there being a report of the RX voltages fighting each other by those that left both red wires connected, and you get the benefit of having redundancy in RX bus voltage supply. I chose to disconnect one of the two red wires, but I usually run a Scorpion Battery Backup for RX voltage backup.

[Wolfgang Wagner]

Hi and thanks for the reply

[Wolfgang Wagner]

There has been a good bit of discussion on this topic. I don’t remember there being a report of the RX voltages fighting each other by those that left both red wires connected, and you get the benefit of having redundancy in RX bus voltage supply. I chose to disconnect one of the two red wires, but I usually run a Scorpion Battery Backup for RX voltage backup.

Ok thx, and you would do it like this with a UBEC too while you plug this one separately into the rx?

[OV10]

Hey guys, I donˋt know, if this question has already been discussed, so I like to know, if it is really that important to cut/remove one of the two red ESC-power (+) wires to prevent possible interferences between the powering of both ESCs. There is a lot of discussion in the web and I am a little bit confused. The P38 has no UBEC, so I think there is one BEC in every single ESC that is powered. And that could cause interferences between both ESCs and in the end harm the electronic and Finals crash the ac. Is that correct and should I remove one of the wires?
Thanks a lot in advance

Hello Wolfgang and welcome to the Squawk.
Unfortunately the search engines on most forums aren't very comprehensive but this question has been answered twice almost 2-3 years ago.
Here's the history that started with the Lightning and culminated with the Tigercat of which I was a focal collaborator on resolution.
https://www.hobbysquawk.com/forum/rc...5270#post35270
https://www.hobbysquawk.com/forum/rc...5280#post35280
https://www.hobbysquawk.com/forum/rc...5077#post55077
https://www.hobbysquawk.com/forum/rc...5084#post55084
Bottom line to the conundrum on this subject, the ESC's used on the P-38 and F7F were new proprietary devices. which allowed keeping both of the BEC power leads used in parallel. ;)

[Wolfgang Wagner]

Hello Wolfgang and welcome to the Squawk.
Unfortunately the search engines on most forums aren't very comprehensive but this question has been answered twice almost 2-3 years ago.
Here's the history that started with the Lightning and culminated with the Tigercat of which I was a focal collaborator on resolution.
https://www.hobbysquawk.com/forum/rc...5270#post35270
https://www.hobbysquawk.com/forum/rc...5280#post35280
https://www.hobbysquawk.com/forum/rc...5077#post55077
https://www.hobbysquawk.com/forum/rc...5084#post55084
Bottom line to the conundrum on this subject, the ESC's used on the P-38 and F7F were new proprietary devises. which allowed keeping both of the BEC power leads used in parallel. ;)

Hi OV10, thanks for your research. Helped me a lot. :)

[PaulZ]

Prop rotation direction: I am curious why the props on the P-38 turn in the opposite of normal direction for a dual-engine plane, meaning away from the fuse rather then towards it? The real P-38 props are reversed to prevent the critical engine issue if you loose one engine. Would it effect the model's performance to switch and reverse the props? Maybe #Alpha can comment?

Note: in both cases the props are counterotating.

[themudduck]

Prop rotation direction: I am curious why the props on the P-38 turn in the opposite of normal direction for a dual-engine plane, meaning away from the fuse rather then towards it? The real P-38 props are reversed to prevent the critical engine issue if you loose one engine. Would it effect the model's performance to switch and reverse the props? Maybe #Alpha can comment?

Note: in both cases the props are counterotating.

Its an interesting thing - I looked it up, the reason was that when they were flight-testing the prototype XP-38 (which had "normal" inward-rotating props) they found that it had a buffeting problem in the tail caused by propwash over the center pod - and they found that reversing the rotation of the two props solved that problem. All subsequent P38's were made that way. Here's the link

[PaulZ]

Its an interesting thing - I looked it up, the reason was that when they were flight-testing the prototype XP-38 (which had "normal" inward-rotating props) they found that it had a buffeting problem in the tail caused by propwash over the center pod - and they found that reversing the rotation of the two props solved that problem. All subsequent P38's were made that way. Here's the link

Thanks! That makes sense...so this is why the Flightline model also has the props reversed. In that case I don't recommend switching them around :-)

[Alpha]

Themuudduck is right, there's a reason why the real P-38's props turn the way they do. We matched that for our PNP, although strictly speaking in this scale and power curve a pilot could swap the rotation if he/she desired without much if at all noticeable detriment.

Kelly Johnson and his team were a cut above to have figured all this out. Compressibility issues which led to the dive flaps, the prop direction, and other quirks were challenges real and immediate during wartime.

[PaulZ]

Themuudduck is right, there's a reason why the real P-38's props turn the way they do. We matched that for our PNP, although strictly speaking in this scale and power curve a pilot could swap the rotation if he/she desired without much if at all noticeable detriment.

Kelly Johnson and his team were a cut above to have figured all this out. Compressibility issues which led to the dive flaps, the prop direction, and other quirks were challenges real and immediate during wartime.

Thanks - it is amazing how much the WW2-era design teams could figure out without computer simulations etc...

[xviper]

Thanks - it is amazing how much the WW2-era design teams could figure out without computer simulations etc...

Having the props go the wrong way likely shook the pilot's kidneys loose from the buffeting vibrations. Probably took them many trial and error tries to figure it out. Mind you, if they could figure out how to make a nuclear bomb, aerodynamics was far enough along that they didn't have to scratch their heads for too long.

[prestonowtm]

Themuudduck is right, there's a reason why the real P-38's props turn the way they do. We matched that for our PNP, although strictly speaking in this scale and power curve a pilot could swap the rotation if he/she desired without much if at all noticeable detriment.

Kelly Johnson and his team were a cut above to have figured all this out. Compressibility issues which led to the dive flaps, the prop direction, and other quirks were challenges real and immediate during wartime.

Hey Alpha..I did figure out or atleast realized why I crashed and burned my first one. During a high speed turn if you are almost full aileron and turn the rudder sharp into it....you better be atleast 2 mistakes high. It did it the other day and thank God I was about 150-200ft up. It hit a certain point in the turn and just dropped into a nose spin. Like a whiplash drop. Something washed out. It wasnt a slow stall that's for sure because I was dead into it. I landed and checked all controls, dropped another set in it and was able to repeat it from about 300ft up which gave me plenty of recovery time. I only tried it with a port turn so not sure if a starboard will do it to. I do this same turn with all my warbirds and it isn't an issue. Just had not flown the 38' in a long time until the other day..any ideas...other than "don't do that" lmao Maybe give it a shot with yours and see...WAAAY up high. When it drops the first impulse is to power off, do the opposite, power on elevator up and aileron opposite of roll..it comes right back out with a little tail wobble. Gets the heart goin' that's for sure.

[Oxotnik]

Hey Alpha..I did figure out or atleast realized why I crashed and burned my first one. During a high speed turn if you are almost full aileron and turn the rudder sharp into it....you better be atleast 2 mistakes high. It did it the other day and thank God I was about 150-200ft up. It hit a certain point in the turn and just dropped into a nose spin. Like a whiplash drop. Something washed out. It wasnt a slow stall that's for sure because I was dead into it. I landed and checked all controls, dropped another set in it and was able to repeat it from about 300ft up which gave me plenty of recovery time. I only tried it with a port turn so not sure if a starboard will do it to. I do this same turn with all my warbirds and it isn't an issue. Just had not flown the 38' in a long time until the other day..any ideas...other than "don't do that" lmao Maybe give it a shot with yours and see...WAAAY up high. When it drops the first impulse is to power off, do the opposite, power on elevator up and aileron opposite of roll..it comes right back out with a little tail wobble. Gets the heart goin' that's for sure.

Accelerated stall. You can make almost any warbird do it if you crank hard enough on the elevator at high speed. Some are more prone to it than others. I don't have terribly high throws on my P38's elevator, but I crank it pretty hard through turns and loops/immelmanns and have never had it fall out of the sky on me. I'm sure that I could make it, though, if I wanted to. It is good to know what the plane's limits are though. With the counter-rotating props, I've never noticed any difference in turn or roll rates.

[prestonowtm]

Accelerated stall. You can make almost any warbird do it if you crank hard enough on the elevator at high speed. Some are more prone to it than others. I don't have terribly high throws on my P38's elevator, but I crank it pretty hard through turns and loops/immelmanns and have never had it fall out of the sky on me. I'm sure that I could make it, though, if I wanted to. It is good to know what the plane's limits are though. With the counter-rotating props, I've never noticed any difference in turn or roll rates.

That's just it...no elevator or just a tad up, full aileron and roll in the rudder to full. Still an accelerated stall? Think I will back my rudder down...lol

[Oxotnik]

I didn’t catch that you weren’t cranking on the elevator. I thought you were banking-n-yanking a turn. I’m trying to remember how I bank mine. I don’t remember using much rudder though. The P-38 is very well behaved for me, assuming that I keep the speed up because it is pretty heavily wing loaded. I have another twin, though, that if I try to bank turn with a low bank angle, she wants to drag her tail so badly that I have to cross control with the ailerons, to make a nice turn. Kinda weird about your P-38. I’ll be interested to her what’s going on, once you figure it out.