The Phoenix HV 45 is suppose to be rated at 2250 watts (3 h.p.) and 45amps continuous. I doubt that my 1200 power system stressed it so I feel that it is the same quality control issue we have been hearing about for over a year now.

We managed to snap a few photos before the ESC quit. The take-off looked beautiful!

When testing my Ultimate 40S just before I was about to tear it apart again, it appears that everything still works fine. Although I am a bit puzzled about what happened during the test flight, I now feel that it must be some shutdown function of the Phoenix HV ESC. The pilot (Devin McGrath) properly tried to re-arm the ESC in flight and we also did it again on the ground without success. This was after a complete re-power up sequence as well.

My BalancePro HD DPM wasn't sounding the audible alarm after the crash but I will still disable it for the next flight test. I will also remeasure the current to see if perhaps the ESC hit an overcurrent shutdown. According to the Phoenix HV 45 instructions, either an overcurrent or undervoltage condition will cause a "soft" motor shutdown. I didn't see any mention of a re-arming procedure.

The problem was an over-current shutdown in the CC Phoenix HV 45 ESC. I was drawing about 90amps full throttle which was fine with my old setup on the Great Planes Lil Toni when using the Jeti 77-amp ESC. The Phoenix HV 45 didn't like it.

I reduced the prop size by an inch to an APC 13x6.5 so it now draws near 70amps at full throttle for about 1500 watts. On a 5lb plane, that's about 300w/lb! The ESC is rated for 2250 watts so it should be ok on my 6s Lithium voltage.

I also reprogrammed the ESC to disable current shutdown and low voltage shutdown as I'll use the DPM to do that. I have good air cooling on the ESC and will never need full power for more than a burst period so we'll see what happens. I see that Castle Creations has a "Castle Link" USB device for easier programming than the programming mode question method I used with my transmitter to set up the ESC.

After some further testing, I realized that my Kontronik 600 motor was faulty.

Yesterday, when I was reducing the prop size, inch by inch, the current measurement didn't seem to decrease as I was expecting. Also, after I re-programmed the CC Phoenix HV45 for no current shutdown and no voltage shutdown, I was surprised when the motor still shutdown at 3/4 throttle. Finally, after replacing the HV45 ESC with a Jeti 77-amp Opto ESC and the motor still shut down around 60amps (Jeti has no shutdown mode), I realized that the high current draw with an 11x7 prop and the shutdowns were symptoms of a bad motor.

I replaced the Kontronik 600 geared motor with an AXI 4120/16 direct drive outrunner motor. Since I was stuck using a 6s Lithium pack, I decided that the 4120/16 will spin the smaller APC 11x7 prop nice and fast for the Ultimate. I measured 53amps at 1100 watts using my 6-cell BalanceProHD Kokam 3200mAh pack which can deliver 64amps continuous so nothing is getting stressed. My new power level is 1100w/5.5lbs = 200w/lb.

Finally, a successful maiden with the AXI 4120 motor. The Ultimate flew great and I hope to get a video today at a local electric event in the Finger Lakes of NY.

Congratulations! So what are your final stats? AUW, power etc?

Colin.

P.S. Can't wait to see the video!

My new power level is 1100w/5.5lbs (or 200w/lb) using the AXI 4120/16 with a 6s Lithium pack. I can't remember what the weight was so I'll have to scan the previous posts.

We got some video yesterday showing the Ultimate in some pretty brisk 10-15mph wind. I'll post it later this week. It had plenty of power and didn't really affect the flight. The combination smaller prop on a 6s Lithium pack really makes it nice and fast!

In the end, I feel that I am better off with a maintenance-free direct drive brushless motor.

photos by "Papa" Jeff Ring

Although the stock foam wheels worked ok on my first flights, they seemed a bit small and soft for the job. After sitting in my trailer for days, the foam would retain a flat spot that made for an uneven roll.

I decided to replace the stock wheels with bigger 2-1/2" Dubro Treaded Lightweight Wheels (250TL). The 5/32" (4mm) axle diameter was perfect for the stock hardware and I only needed to round the outer ends of the pant opening. The firmer rubber wheel should provide for better ground handling.

Although it was rather windy, my Ultimate 40S still tore up the sky!

[link=http://www.gregcovey.com/reviews/Ultimate40Selectric.wmv]Ultimate 40S Video[/link] (7meg)

Nice video... looks like it flies very well with that setup. So how much flight time do you get with those batteries? I was looking at that kit for my third or fourth glow plane and from the looks of things it is very agile.

Thanks,

Mark

Nice going Greg! At last ... the project is COMPLETE. Mine is still awaiting a SECOND re maiden. After I had gotten my new batteries and did my remaiden, the same thing happened ... motor shut down after about 10 seconds. Luckily I was over some high grass at the side of our field and was able to make an uneventfull crash landing.

I subsequently discovered that it wasn't my batteries afterall but rather a faulty ESC. [:@] Anyway, I just got my replacement ESC about 10 mins ago so I'll probably be RE maidening mine tomorrow. Fingers crossed!

Colin.

Good luck, Colin!

Well ... I got in my maiden last week and then some! Plane flew beautifully and FAST! This and I'm only running it at about 650 watts (still breaking in my batts) at about 5lbs 3 ozs auw. I intend to end up running it at 750 watts when my packs are broken in.

The only minus I see is the slow roll rate due to those really small strip ailerons. I think one of the big chracteristics of a "muscle bipe" is a blinding roll rate but otherwise its GREAT!

Colin.

P.S. BTW, Greg ... whatever happened to the Seawind amphibian conversion that you were doing at some point? (I read about it in some thread or the other.)

Colin,

I'm glad yo hear that you Ultimate flight went well. You will find that the roll rate will increase rapidly with just a little more throw. If you use a computer radio (like my Futaba 9C) this is as easy as increasing the end points. If your CG is too far forward, it will also dampen your roll rate.

The Great Planes Seawind project never materialized and they did not want to send me one of the first run blemished units. It is a great looking scale model that will be around for a long time...so you never know.

I realize this is a 20 years old paleo thread but was recently given one of these NIB. I am usually a BMO modeler but this ARF is nicely constructed and looks strong and light. On the off chance somebody is still alive out there who has experience with this model, would this electric motor be suitable or what would be suggested, ESC also? For sport acro flying.

Horizon Hobby Power 46 Brushless Outrunner Motor, 670Kv, 3.5mm Bullet

I am also considering staying with glow and using an O.S. 50 class four stroke or a NIB O.S. 46SF Ring. Pitts style exhaust for these are hard to come by these days so that is more why I am considering electric conversion so I do not have to cut the cowl all up. Though, really, I think I prefer glow and a Pitts exhaust if I could find one.

I saw the tip on the CG to go with 2 and 7/8 inches back on the top wing at CL. I know very little about electric motors, very new to that thinking, always flown glow engines.

From my 2014 notes.

WORLD MODELS ULTIMATE 40

Wing (top) 42”.

Length: 39.5 inches

578 Sq inch

Wing loading is 19.95 oz per sq foot at 5lbs AUW.

(wing area divided by 144 = 4.01 … then weight divided by that number)

Wing CUBE loading is 10 (http://www.ef-uk.net/data/wcl.htm)

AUW weight recommended is 4.5 to 5 lbs.

My AUW weight is 80ozs or 5lbs.

Watts per pound at WOT is 129 (at 5lbs) with motor putting out 644 watts (46A) with 12x6 APC E prop.

Wind speed limit with MY plane = 32kmh or 20 mph – Optimum is 15kmh or 9mph.



ACCORDING TO “KMP647” (http://www.rcgroups.com/forums/showt...odels+ultimate+ )

142 WATTS PER POUND GIVES HIM UNLIMITED VERTICAL WITH HIS 14X10 PROP!

ACCORDING TO THE HACKER / DP ULTIMATE VIDEO 120 WATTS PER POUND (900w / 7.5lbs @ 45A X 20V GIVES AMAZING SPEED AND VERTICAL PERFORMANCE WITH ITS 15X10 PROP!

Plane without battery, power plant, receiver or servos. (just kit weight) = 43 ozs

The following is its kit weights:
Cowl: 2.1oz (Lighter because of hatch I cut out)
Vertical feathers: 1.2oz
Canopy: 1oz
Pants: 1oz
Horizontal feathers: 1.9oz
Fuse: 9.1oz
Top wing: 7oz
Bottom wing: 7.2oz
Hardware including 2.25” spinner and 2.5” wheels: 10.1oz (BTW, Scott suggests 2.5” wheels as opposed to the 2” stock for bumpy fields)

TOTAL KIT WEIGHT = 40.15oz

Plus the following components:

HYP 4020-10 (60A/70A peak - 5 cell max) and prop adapter and bullet connectors: 10ozs

COMPLETE Back Motor mount: (with their backplate and bolts, my bolts and PVC pipe etc) 3.75 ozs

ESC: (80A Opto) 1.75 ozs

Prop: 12x6 APC – .75oz

4S 4200 Polyquest 16-20C battery: 13.85 ozs (Includes Sermos connectors for battery: .25ozs)

Receiver: .6 oz

UBEC: .7 oz

Switch: .5 oz

3 HS225MG servos: 3.75ozs

Misc: (Glue, Battery tray mods etc) 4.2ozs

TOTAL COMPONENT WEIGHT = 39.85 oz

TOTAL ALL UP = 80oz (5lbs)

(Greg Covey’s is 5lb 10ozs/90 ozs with 20oz battery PLUS extras like switch, DPM module etc)





TIPS!

Tip on landing gear.

Knock out the blindnuts and put in nuts that fit nylon bolts. That's about 20 minutes of work that'll be well worth it. The gear is on a plate that has no structure behind it to support a hard hit. So the hit tears out the wood. With nylon bolts, it pops the heads off and you screw in new ones. I used 10-24 nylon bolts as an experiment.

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Power produced:

PROP FOR 47A (70% OF BATTERY’S RATING) FOR FIRST 10 FLIGHTS!

With 12x6 prop = 646 watts at 47 amps and 13.75 volts. (16C - 4S pack @13.75 ounces)

Since THIS plane is 80 ounces, the watts per pound is 129

ULTIMATE’S flying time with 4S 4200mah (16C) pack at 47amp draw.

(13.75V @ 47A = 646W = 129w per pound @ 11.19C WOT discharge rate.)

Motor amp draw is 47 amps or 47,000 mah.

UBEC amp draw is 3 amps or 3,000 mah

50,000 mah divided by 60 minutes is 833

Battery capacity of 4200 mah divided by 833 = 5.04 minutes flying time at full throttle.

Since I fly at 65% of the time at full throttle my flight time should be 5.04 minutes divided by 65% = 7.75 minutes (In reality I got 8 minute flights at this amp draw)

Thinking in glow terms, what RPM range would I try to turn a 12X6 or the 14X8 prop? RPM is determined by load and the KV rating to determine approximate max amperage loaded RPM? More of a general question not completely specific to this model.