Something new from something new—now the star shines

I was satisfied, but a little more power and a better look are always welcome. So I had to get all the aftermarket parts. Each reader must judge for themselves whether this was a good idea or not. To cut to the chase: The helicopter is now really g ...! The high-quality parts are a real feast for the eyes. Made of light gray aluminum, they’re cleanly crafted, lightweight, sturdy, and precise. I was most excited about the performance boost promised by the new 1500W tuning motor.

Will the Hurricane 550 finally become a true 3D helicopter? I also swapped out the original speed controller for an Elektronik JAZZ 80-06-18. I said goodbye to the wooden rotor blades a long time ago and now use the HeliTec 515 CFRP ones. I couldn’t get used to the original swashplates either, so I tested the extra-light Align swashplates for the 600 T-Rex. I was particularly drawn to the look of these swashplates, but unfortunately, the Hurricane tends to buck, causing it to veer off course quickly when flying straight ahead

turned into a wave ride. The yellow JR paddles are about 2 grams lighter and slightly larger than

the original paddles. As a result, the flight characteristics have become very impressive.

Basically, I’ve installed all the available tuning parts. That means the entire rotor head and deflection levers, as well as the motor and gear pinion. I’ll probably treat myself to the new CKF chassis someday, too. I hope that tuning parts for the tail linkage and tail rotor will become available over time as well. The conversion is simple. It’s worth following the assembly instructions carefully so that no washers are forgotten and no other minor mistakes creep in. Once again, the rule is: don’t skimp on threadlocker. After replacing the push-pull linkage levers, you’ll need to adjust the linkage. It’s very important to ensure smooth movement; otherwise, all that nice tuning is for nothing. Here’s a little trick: use flat-nose pliers to gently squeeze the ball sockets on the ball joints—but be very careful—to make them move more smoothly. You’ll need a bit of finesse; if you overdo it, the connection might develop play. Another option is to ream out the ball sockets using a special tool. Note that the GA204612 deflection levers for the push and pull linkages must not be installed without shims. Otherwise, the screws securing the ball joints might rub against the tuned motor, which could cause malfunctions. The new motor is quite a bit

larger and 32 grams heavier than the original motor and fits only very tightly. So I grabbed a file and created a little more space for the motor. A fiberglass cowling is now also available. Since the PVC cowling is lighter, I opted for that version. It’s a bit annoying that the cowling isn’t stable enough around the mounting rubber bands. It tears, and it’s no longer possible to reattach the cowling. Thin fiberglass mat with PVC adhesive helps with this. Treating the rubber bands with silicone grease regularly also helps. In the meantime, I’ve picked up various cowls in different designs. The motor is a real “tune-up”! The increase in performance is significant. Warning! The motor must only be operated with a No. 12 pinion. Furthermore, it’s absolutely necessary to replace the gearbox pinions. There are new OK pinions available—that is, the new pinions have a white “OK” stamp and can withstand more stress. In my case, I made the maiden flight with the tuned engine and

The “old” sprocket: The fun lasted just 3.5 minutes, and the sprocket was gone. The tooth flank clearance must be adjusted precisely. The adjustment process is quite fiddly, but it’s worth investing the time here. The sprockets will reward you with a long service life. I also noticed on my Hurricane that the front sprocket of the two-speed transmission was rubbing against the chassis. So I filed down the chassis a bit in that area.

The rotor is spinning at 2,200 RPM—I think that’s the maximum for this helicopter. The ESC is in helicopter mode, which means it maintains the preset rotor speed at a constant level. The throttle curve is linear and quite flat at about 50%, allowing the ESC plenty of room to make adjustments. The tail servo travel is set to 140%, which provides good pirouette speed. Pitch is set to +12/–11 degrees. A greater negative pitch won’t work, as the swashplate would otherwise bottom out against the swashplate guide if the pilot needs to pull back fully. After the modification, it’s necessary to readjust and check everything again. In the air, the Hurricane is now unrecognizable and truly lives up to its name. Plenty of power! Hover, then full pitch—the helicopter shoots into the sky; pure joy! It handles every maneuver the pilot can think of and is capable of performing. With the HeliTec blades and JR swashplates, it flies

as steady as a board in the air—even in really strong winds. Up and down, inverted or right-side-up. Only during really fast reverse flight is the tail a bit spongy. The Hurricane is now a true 3D helicopter: crisp, agile, with plenty of power—a competitor that demands attention. Of course, the flight time has decreased. But that’s not surprising given this increase in performance. With the configuration described and a power-intensive flying style, it’s about 6 minutes. The motor gets pretty warm. On really hot summer days, make sure to provide good ventilation. The servos’ power consumption has also increased, so the 900mAh battery needs to be recharged after two flights. One more note about the LiPo batteries. During the testing phase, I used the previously mentioned EMax 3S 4400 mAh cells and the ePower 3S2P 4200 mAh cells from eflight.ch. I feel that the ePower cells deliver power more smoothly; the voltage stability is definitely better. With the ePower cells, I had to reduce the speed control by about 6% to keep the RPM from exceeding 2,200. The ePower cells are also about 30 grams lighter per 3S pack.

Winter is just around the corner, and the flying season is coming to an end—at least for most of us. So, why not start a new project in the workshop?

Happy tuning and have fun
! René Stoll

Model-building accessories to take off!

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