Phoenix 71" Corsair on electric

[cartrouble2k]

Hey everyone - I am thinking of getting the Phoenix 71" Corsair and running it on electric. I am curious what motor/esc/prop combo people have on it. Phoenix recommends the Rimfire 1.20, but that is no longer made and has been replaced with the Spektrum Avian 5065, which produces ~1800W continuous and 2200W max. I think that should be about right.

How do people like the electric retracts it comes with? I have heard they are a bit iffy - is there a way to replace them with something more durable like a set from Robart or am I stuck with Phoenix's retracts?

Thanks a lot!

[kevinkal]

I have been flying the Phoenix 20cc Corsair (71") for about 11 months now. Although I went with a gas motor, I can tell you that a little extra power would be a good idea. It's a bit larger than other 20cc warbirds I've seen. The landing gear has been great, the electric version that is. It works just fine if you're not flying too fast when you drop the gear. The gear controller requires a 2S LiPo and it appears to sense current load and shuts off if it sees approximately 0.7 to 0.8 amps at roughly 8V from a small (~300+ mAh) 2S LiPo under load. If you're flying fast, the airloads on the large 4" diameter tires turned cross to the airflow and the drag on the shin fairing will push back on the electic retract motor and can cause it to stall before the gear is down and locked. I recommend doing "gear check" fly-bys until you are used to the landing gear operation. If it does stall, you can simply cycle the lannding gear switch and it will try again. I've found that slowing down, dropping half flaps, then putting the gear down works every time.

[cartrouble2k]

I have been flying the Phoenix 20cc Corsair (71") for about 11 months now. Although I went with a gas motor, I can tell you that a little extra power would be a good idea. It's a bit larger than other 20cc warbirds I've seen. The landing gear has been great, the electric version that is. It works just fine if you're not flying too fast when you drop the gear. The gear controller requires a 2S LiPo and it appears to sense current load and shuts off if it sees approximately 0.7 to 0.8 amps at roughly 8V from a small (~300+ mAh) 2S LiPo under load. If you're flying fast, the airloads on the large 4" diameter tires turned cross to the airflow and the drag on the shin fairing will push back on the electic retract motor and can cause it to stall before the gear is down and locked. I recommend doing "gear check" fly-bys until you are used to the landing gear operation. If it does stall, you can simply cycle the lannding gear switch and it will try again. I've found that slowing down, dropping half flaps, then putting the gear down works every time.

Thanks, that is really helpful. Interesting - so you have a separate lipo for just the gear controller? My only experience with retracts have been with foamy PNP EDFs, and that doesn't really involve any setup.

What gas engine do you have in it btw? It's a "20cc" bird, but I have seen online that some people put a DLE 35 in it! I am all about having as much power as possible, but I just don't want to overstress the airframe either.

How did the plane balance? I am thinking about putting an E-Flite Power 160 in it - that's 2700 watts (more than the recommended 1800-2200 1.20 Rimfire). If the plane typically needs nose weight to CG properly, might as well just stick a bigger motor in there :)

[kevinkal]

Thanks, that is really helpful. Interesting - so you have a separate lipo for just the gear controller? My only experience with retracts have been with foamy PNP EDFs, and that doesn't really involve any setup.

What gas engine do you have in it btw? It's a "20cc" bird, but I have seen online that some people put a DLE 35 in it! I am all about having as much power as possible, but I just don't want to overstress the airframe either.

How did the plane balance? I am thinking about putting an E-Flite Power 160 in it - that's 2700 watts (more than the recommended 1800-2200 1.20 Rimfire). If the plane typically needs nose weight to CG properly, might as well just stick a bigger motor in there :)

Well for my gas setup, I have a 2700mAh 2S LiPo for the Rx, an 1800 2S LiPo for the Ignition and a 460mAh 2S LiPo for the gear. The gear might draw close to 2 amps if you drop them at high speed, just before they stall out. I figured I'd better be safe than sorry;
I do have a DLE 35RA in my Corsair. It balanced perfectly, with all the LiPo battery weight pretty much right on top the CoG. If I used a smaller lighter engine, I could have shoved the batteries about 6 inches further forward to compensate and thus have a lighter airplane... but not by too much, perhaps a few ounces.

I've posted some details on stress concerns with the wing structure of this model. The primary concern is with the wing sheeting joints on either side of the landing gear cutouts near the leading edge. The wings I've seen just have balsa sheeting that butts into the lightweight balsa plywood right at the landing gear cutout area. These wing sheets need to transfer load across the landing gear area. If the butt joints crack (as they ALL seem to do over a short time), then the wing bending stresses are transferred more and more to the leading edge itself, which will then begin to crack... as this point the wing is about to suffer a catastrophic failure unless you make some simple, but critical repairs.
I think anyone who owns one of these birds should periodically check their wing structure for cracks that might form in higher critical stress areas. Basically, look for signs of cracks under the Oracover / Ultracoat. If you put a light bending load on the wing up and down to simulate flight loads, you might see a crease come and go in the covering. In my case, I monitored the crease until the covering actually tore at this crack. At this point, I made some small, simple and highly effective wing joint and leading edge crack repairs. This was at approximately 80 to 100 flights. I'm guessing I've got over 160 flights on this bird now and the cracks have not come back... even with typical flight loads peaking around 4g's and occasionally to 6 g's..

Gas engines do put a significant vibration load on the airframe.. so you may not have as much issues with the wing joints cracking with electric power. Just beware of this possibility and keep an eye out for cracks.

You will love your Corsair. Hopefully your wings will slide on without much force... unlike mine!

[cartrouble2k]

Thanks a lot! Hmmmm.....so this will be my first warbird and most complex ARF for sure. I've been flying PNP foamies and Extreme Flight balsa ARFs up to this point (my main interest is 3D flying but I am definitely curious about warbirds).

Seems like with the Phoenix Corsair, as well as every other warbird ARF I've read about, there are a lot of potential structural issues you need to be aware of that I frankly don't know how to look for. That tells me maybe I should start a little smaller. Either maybe with a foamy warbird so I can decide how much I really like warbirds, or get some sort of kit to build so I can properly learn all this stuff.

The problem is there are very few interesting-looking kits out there. Seems like it's Balsa USA and SiG, and none of their planes look terribly "cool" or interesting to fly to me.

Any suggestions? I know this is off-topic but you seem very knowledgeable :)