New FMS 1700mm Corsair V3

[bandetx]

I’ve had the V1 and currently the V2 and yes, there is a crap load of weights in the cowl - way, way more than what it normally takes to balance a car rim/tire. I would have thought that FMS figured some way to address this situation in the V3. I don’t know of any other model plane that needs 1/2 lb. of weight to be added by the end user.

The full size one would have a much proportionally lighter tail and a heavy engine.

[davegee]

Thanks for that info, 406Pilot. I hope you are able to make the Super Corsair as you plan to do. I love that R4360 P&W engine, It's been on many planes, not just a few variants of the Corsair, but planes like Howard Hughes' Spruce Goose, the C-124, C-97, B-36, and others, too from that era.

[406PIlot]

The Rimfire 1.20 that i picked up had an internal issue. Bad bearing or wasn't shimmed correctly. So I have to send that back into horizon. So I don't have any results for testing that motor =(


Davegee - I may end up just putting extensions on the motor mount to push it forward. Then i'll use fiberglass to extend the cowl (or lengthen it) most likely. I'm not 100% sure, but that's my initial thoughts on it. Pushing the motor forward will also allow me to take out the additional weight and still hit that sweet spot for the CG. I need to do some measurements and figure out how far out I'll go and how much I'll need to extend the cowl. But that will come later this winter when i get into the project of actually converting it.

[davegee]

I had watched the RCINFORMERS videos on this as well. I agree it seems underpowered in it's stock form. I'm going to try it for myself before making any changes. I am planning on upgrading for more power. I was thinking about the RimFire 1.20 450kv to keep it as a 6S setup, but i'm not sure on that yet.

I will for sure need more power than it's stock form since I am planning on repainting mine in the F2G Super Corsair #57 Scheme.

If anyone has thoughts on power setup please post them up.

Sounds like a very cool project! How are you going to lengthen the nose to house what was a P&W 4360 engine that they used in it?

[406PIlot]

I added up the weight again. I added 8oz exactly 1/2lb of lead to the cowl. Here's a picture.




I'll be putting in the RimFire 1.20 50-65 450kv a little later this morning. I'll post an update with the numbers on that later.

[xviper]

I’ve had the V1 and currently the V2 and yes, there is a crap load of weights in the cowl - way, way more than what it normally takes to balance a car rim/tire. I would have thought that FMS figured some way to address this situation in the V3. I don’t know of any other model plane that needs 1/2 lb. of weight to be added by the end user.

[406PIlot]

And yes I actually added 10oz of weight to the cowl. It fly's perfect after adding the weight. I'll add a picture of the cg point later tonight or tomorrow.

[406PIlot]

I am going to try a rimfire 1.20 450kv on 6s and see how that goes. Just got the motor today. Will get it installed and check amps n watts to see how it stands with the stock prop.

I'll post an update after getting it installed.

[Aros]

I'm with you Hugh Wiedman. FMS had plenty of data and feedback over the years from V1 to V2 to know one of it's biggest knocks was a lack of power (and small prop). They would have really impressed me had the V3's stock setup be what it is on the 8S mod. You're right, now just to get it to fly with the power it deserves you're over $600 into it.

[Hugh Wiedman]

I'm still baffled that FMS would come out with a V3 that is still underpowered, as the V1 and V2 were. What's the point? I'm sure on 8S it flies sweet (as demonstrated by RC Informer), but then they should have done that to begin with on the V3. At a cost of $500 plus another $100 or so for an 8S ESC, it's now up to $600 US. Specs say it still is as heavy as before at over 11 pounds, while the FL 1600mm Corsair at $439 is closer to 8 pounds, and only 4" less in wingspan. And IMO that Corsair flies exceptional. Don't get me wrong, the Corsair is my favorite prop warbird and the bigger the better, but the V3 IMO leaves a lot on the table when they could have knocked it out of the park. I still occasionally fly the FMS 1700mm P-51 and I love the large size and presence in the air, but it too is underpowered, even with the 360Kv motor in it. The lighter the battery, the better it flies, and I now fly it on a 3300-4000 mah battery at the most, but then again flight time is seriously reduced down to 4:30 versus my Corsair at almost 8:00 with a 5000 mah.

And 406PIlot , do you really mean that you added 10 ounces of lead to the nose? That's well over 1/2 pound, must be a misprint. Why not just put your cat in the pilot seat?

[Aros]

Congrats! Nothing like a successful maiden. What's your plan for upgrading the power? 8S or different motor, etc?

[406PIlot]

Completed the Maiden this afternoon. It went great! I can say that the book low rates are still more throw than needed with the exception of the rudder. You can use all the rudder throw and it feels good. After the maiden i did add 10oz of weight to the cowl just like RCINFORMER. This made it a lot more stable.

It does feel extremely scale with the stock setup. I upped the timing to high on the ESC after the maiden flight. That made it a little better, but it lacks power in my opinion (which a lot of people said). It needs a bigger motor or the 8s setup for sure. Here are a few pic's from the runway today.

[406PIlot]

Finished the build up early this morning. I had to do a little adjustment for the control rods on the flaps & elevators to get everything at a good neutral position with even throws. So nothing major there. I did move the elevator control rods in on the servo arm same as RCINFORMER had done. This gave just about perfect travel. The rudder is the only thing that seemed to be way out of wack. Stock positioning (how everything was out of the box) gave the Rudder 50mm of travel in both directions. That seems excessive since the manual calls for 24mm "high rates". I setup Mid rates & Low rates that give it closer to what the manual calls for. I left the high rate at the 50mm of travel. We'll see how it does.





I also hooked up the power meter to see what it was doing in 100% stock form. No changes to timing or anything as is out of the box this is what I was seeing.






96.89Amps & 2265.2 Watts

[bandetx]

Normal for planes to have motor offset. It's for torque.

A lot of modern planes will actually have the rudder offset very slightly to one side of the fuselage to counter it.

[RRHandy]

Ok so ran into my first questionable issue during assembly. While looking at the motor & motor mount I noticed that it seems tilted to one side. I took the cowl off and you can clearly tell the Motor Mount isn't square in the fuselage. Here are a few pictures.






It's pretty clear there is an offset with how the motor mount is in the fuselage. Is this normal? Does anyone have thoughts on this?

Unlike the full scale plane that you could trim out torque with the rudder and trim tab, the motor is placed that way in leu of it. if you look at the cowling it too has this in it.

[xviper]

I watched RC Informer's video with this model on 8S and that is absolutely the way to go with this bird. I was hoping for the V3 FMS would have learned to put a robust power plant in it but it appears that is not the case. So he tried it on 8S with an upgrade to a 120A ESC and that seemed to be the fix. Once I get this bird I will be planning on the same thing.

Yup, planning to do that myself. Ordering the FMS HV ESC for 8s and putting the 300kv motor back into the V2. Maybe even going for the bigger V3 prop. At least it has that metal piece in the hub to help prevent the thing from disintegrating at high speed.

[Aros]

I watched RC Informer's video with this model on 8S and that is absolutely the way to go with this bird. I was hoping for the V3 FMS would have learned to put a robust power plant in it but it appears that is not the case. So he tried it on 8S with an upgrade to a 120A ESC and that seemed to be the fix. Once I get this bird I will be planning on the same thing.

[timmybeetle]

Price

Well it's an FMS plane and again I read about upgrade motor, I owned a V2 and I upgrade motor to a 5065-360KV.
But V2 had a 17 inch prop (pitch 10), this V3 has an 18 inch prop (pitch12).
Also I read here about connector from ESC to LIPO and ESC is only 80A, again maybe you have to replace that too adding the price up.
BUT price in EUROPE is between 589-679€.
For that kind of money I would rather buy a balsa in stead of a foam plane.

Regards Hans

ps if I read here that he has questions about down and side trust of motor mount than I have second thoughts about his knowledge regarding model-plane flying.......

[AirHead]

I just got done chatting with Horizon to see what they said. Exact same answer as you AirHead. Appreciate the info. I'll get the ESC & Motor back in it once I put a new connector on the ESC. Baffles me 80amp ESC with a 60amp connector on it. Not that it should be a real issue, but stupid stuff like that drives me crazy! So the XT60 connector is getting swapped out to an EC5.

Well, that goes to show you that you CAN trust an airhead. Maybe not all the time, but at least this time around. As for the XT60's, I've seen many big batteries and ESC's with either Deans or XT60's. I use 8mm individual bullet connectors with the spark arrestor on the ESC side for 6S planes. I switched all my old Deans for XT60's on the 3S stuff. Not long ago, XT90's came along with a built in spark arrestor.

[406PIlot]

I just got done chatting with Horizon to see what they said. Exact same answer as you AirHead. Appreciate the info. I'll get the ESC & Motor back in it once I put a new connector on the ESC. Baffles me 80amp ESC with a 60amp connector on it. Not that it should be a real issue, but stupid stuff like that drives me crazy! So the XT60 connector is getting swapped out to an EC5.