Official Nexa 2100mm F-82 Twin Mustang (Balsa ARF) Discussion Thread

[Ah's Availble]

Twisted Grin,

I agree with you, Great flying model. After second flight one of my motors failed. My fault for buying cheap motors! Spent a month installing upgraded Surpass motors. Then re-maiden with slightly larger props. No issues with P-Factor and it jumped off the ground so quickly I was surprised for a 25lb model. I have about ten flights on mine now using 6S 5000mAh batteries. Averaging 8 minute flights with mixed throttle doing aerobatics and lots of low fly byes. Looks great flying and is so smooth. Very predictable landings with full or partial flaps. Landing lights definitely a great add. Used the ones from the Freewing 1410mm P-51 "Old Crow". Surprised that Motion hasn't marketed this unique warbird more.

Happy flying!

[TwistedGrin]

Really enjoying flying this aircraft....flies on rails, fully acrobatic. Formidable speed at WOT burst (I refrain from flying WOT as I would rather cruise and do aerobatics).....take off and landings are very smooth and predictable

Highly Recommend this model to "seasoned ARF" builders

I am thinking of inserting a section of rubber hose to help the outer wing screw stay captive to the wing tube

TwistedGrin

[TwistedGrin]

Finally was able to get a full flight video of this model....and in calm steady winds. Real joy to fly with no evil stall or weird performance issues......The actual rubber wheels are breaking down so the second set will deploy soon

https://youtu.be/uQsxbNBJhtw?si=A-xTsvC6XrmHKQ56

TwistedGrin

[TwistedGrin]

Just completed running the numbers via eCalc for a 5s LiPo scenario to see how much weight loss could be achieved.....turns out the CG would require 73grams added to the nose even though the 5s 50c 5000mAh LiPo where placed all the way forward.....the power system could run the same motors turning CR 14x8 XOAR PJN props. This package would be a little bit slower and have less flight time.

The weight savings would wind up at or near 129grams

No real advantage....the Watts Per Pound thrust value stayed the same, stall speed stayed the same, Top and 72% throttle speeds reduced, flight times reduced....the wing loading is nearly the same

TwistedGrin

[TwistedGrin]

I noted the motor was loose while replacing the broken prop.......also noted the motor label had come off and small shreds found on the inside of the cowling. After triple checking the motor mount gap from firewall and cowling....I put a drop of CA on all the motor bolt nuts on both fuselages. Just a note to check over your motor mounts often

TwistedGrin

[TwistedGrin]

Wednesday 06-26-24 Left Side Pilot Captain Landon Gear was left in dismay after nosing over and breaking his port side prop - Right side Pilot Ed Propernaught maintained his composure as we await 12x8 XOAR PJA replacements

Having lots of fun flying this bird

TwistedGrin

[TwistedGrin]

I was pretty apprehensive to fly this thing....it seemed heavy on paper and heavy fully loaded on the bench.....I guess the main wing is akin' to the Bronco Hershy Bar for light wing loading. The odd factor goes up for this bird and so does the flight performance factor.....win win cool bird!!

TwistedGrin

[Twowingtj]

Congratulations on the maiden!

These Nexa F/P-82s are one of the nicest flying twin warbirds out there.

[TwistedGrin]

I maidened my "Double Eagle" this evening plus two more 7minute lazy eight flights - Dual 6s set up with Aura8 stabilizer.....very smooth and docile. Lands as others report.....super smooth with flaps....Excellent model.....looks way more aggressive than it flies.....Another Happy F-82 pilot !!!

TwistedGrin

[Twowingtj]

Congrats on the maiden!

[dovenden]

Did the maiden on mine today and flew beautifully. CG was just behind the book recommendation with 2 4S 4000 Lipos. Nice aerobatics, stable flier and lands nice and slow with full flaps. Very happy!

[Twowingtj]

With the two tail wheel retracts, you might need some nose weight to get the CG in range.

[Ah's Availble]

Thank you! I really didn't want to add all that weight in the plane.
I already added gear doors, lights, tailwheel retracts and 1.5" to the air scoop.


Plan to maiden soon.

[Twowingtj]

Mine is balanced at 96mm with no extra weight needed. I'm using 2 ea. 6S 5000mah packs. I had to mod slightly to get them to fit. Flys great!

[Ah's Availble]

I am currently preparing my P-82 for flight.


Worried about that crazy mismatch of CG in the manual. Hoping somebody has flown this and can help me figure out the best match. I found one video online and the guy said he set it up to the manual and as it took off he says "oh, it is tail heavy"..
..

Anybody out there with a useful CG for this? It is heavy already and my calcs show 1.125 lbs needed with 6S 4000 batteries on mine.

[davegee]

I am still holding for a day to maiden....need my skill level refreshed and ready for a maiden in favorable weather and runway conditions......as I look back on my years of flying and maidens.....90% of my losses are the month of March......too impatient to wait for a good day and too eager to maiden when my reflexes were not ready

TwistedGrin

I Hear 'ya, TwistedGrin! Sometimes it's hard to know when to walk away and come back on a better day. I've lost a few where I should have punted that day and come back when conditions were better!

Good luck with it, whenever the time is right to do your maiden!

Cheers

Davegee

[TwistedGrin]

I am still holding for a day to maiden....need my skill level refreshed and ready for a maiden in favorable weather and runway conditions......as I look back on my years of flying and maidens.....90% of my losses are the month of March......too impatient to wait for a good day and too eager to maiden when my reflexes were not ready

TwistedGrin

[TwistedGrin]

Nearing the completion of my assembly:

Notes:
I needed 350g nose weight to achieve 96.5mm CG (inverted wheels retracted)
This leaves me "some" room to move my batteries forward if needed
I also needed to deploy the battery tray at the very bottom of the fuselage cavity
Supplied plastic spinners warped (Unusable) - Deployed ZYHobby 3.25in Aluminum Spinners
ZTW 85amp ESC's mounted inside motor boxes
ZTW 18amp BEC left side fuselage pulling power from left side 6s 50c 5200mAh flight battery
Aura8 Stabilizer Brick mounted to left side center wing
ElectroDynamicsInc 3pin quick connects for each fuselage
ElectroDynamicsInc 2pin quick connects for each wing
Hitec HS D645MW Servo for Aileron, Elevator, Rudder
Hitec HS 85BB servo for Flaps

My right vertical stabilizer was biased with an inboard warp....managed to get most of it out during epoxy cure. I still wound up with some inward angle which now translate to a slight curve in the horizontal stabilizer.....washers on top of the wood elevator tangs help mitigate most of the curve.

Both cowlings had issues mounting evenly to the right fuselage.....the left fuselage cowling mount is easily perfect. Larger cowling screws were used to secure each side.

I noticed there are left and right control horn slots for each flap - I managed to get one of them on an opposing side of the other two - forcing me to deploy a servo reverser for that servo.

Used 3mm socket bolts for the wing spar....tapped the spar for 3mm bolts for Left-Center-Right wings

Aura8 Stabilizer control brick mounted to the center wing underneath left fuselage with two Spectrum Receivers to which the right receiver is mounted inside the right center wing for DX8 Radio

I chose not to run a parallel battery loom....mostly for weight savings and the XT90 dual connectors would also encumber the batter compartment and I would still need a RX power supply somewhere.

To add a little color variation I opted to paint the elevator and rudders and wingtips red. I found the plastic wing tips needed sanding and primer coat for the "Valspar Project Perfect" rattle can red to adhere.... I think the plastic caps still had some release molding residue I could not remove !! Figured I'd fly this color splash and see how it looks to me before painting some more.

Tuning the flap servo's it is mechanically impossible for the 85BB servo short arms to reach the 35mm deflection....I am installing longer servo arms and also flipping the control rod connectors to the tops of the servo arms.....otherwise the angle from the flap horn will also bind up.....I am not too confident the power of the servo's either...time will tell

The tailwheel control arms prevent full range of rudder servo movement if you attempt to use the outer hole of the rudder control horns.....therefore the inner most hole of the rudder control horn may be the only means to get the full range for the suggested manual 35mm rudder travel.

At the moment I plan on storing and transporting with the twin fuselage and tail section fully assembled.....separating the two outer wings for quick field assembly.

I use eCalc with excellent results in my other models......eCalc is showing the smaller 12x8 props on my 6s LiPo and 85ESC combo is a sweet spot.....172watts per Lb / 85mph WOT / 9min flight duration at 72% throttle / 62amps at WOT

My total all up flying weight is heavy at 16.04lbs and if I used the correct wing area number 50dm2 this could have a wing loading at or near 47.7oz/ft. This explains the stall speed at or near 36mph......I usually try to fly at less than 41oz/ft....so this bird may have to land a bit faster than I am used to.

TwistedGrin

[Bellke]

ADVISORY ALERT:

The NEXA F-82 delivers equipped with Retracts and Landing Gear Pre-INSTALLED.

Contrary to the list of equipment "Required" on MotionRC WebSite:
Retracts are not required via separate purchase
Landing Gear Struts are not required via separate purchase

Advisory Complete

TwistedGrin
Also Noting: The model is delivered with pre-hinged and glued control surfaces.....Aileron, Flap, Elevator are Dubro Nylon Flat hinges / Rudder hinges are CA

I'm on the fence with this one.. please keep the info coming. Looking forward to seeing the build.

[Twowingtj]

The supplied retracts and struts work great, zero issues.. The struts are sprung perfectly for the weight. I did lube the pistons with silicon and work them a bit to smooth their movement out.