Rare Bear

Specifications Model type: Semiscale electric-powered foamie Skill level: Advanced Wingspan: 34.6 inches Wing area: 287 square inches (2 square feet) Length: 34 inches Radio: Spektrum DX8 2.4 GHz transmitter, Spektrum AR636A receiver (included), four E-flite A320 servos (included) Components needed to complete: Four-plus-channel transmitter, 4S 3,300 mAh 50C LiPo battery Minimal flying area: Club field Price: BNF $229.99; PNP $199.99 (does not include receiver) Power system: E-flite 15BL 1,200 Kv brushless motor (included), E-flite 70-amp ESC (included), 8 x 8 propeller (included), E-flite 4S 3,300 mAh 50C LiPo battery (not included) Power output: 61.6 amps, 963 watts, 341 watts/pounds Flying weight: 2.8 pounds Flight time: 3-6 minutes Wing loading: 22.7 ounces/square feet Cube loading: 16.1 Pluses • Easy assembly • Well-executed, visible trim scheme • Performs fast and aerobatic flights Minuses • Launching can be tough • Hatch grip is unattractive The Grumman F8F Bearcat was designed during World War II with the goal of having the smallest and lightest airframe matched to the most accessible powerful engine. This resulted in an airplane that could outclimb nearly anything else in the sky. The same “big engine, little airplane” philosophy also proved popular with air racers, who have used military surplus Bearcats to good advantage around the pylons. One of the most ubiquitous racing Bearcats, Rare Bear, found unprecedented success by making the airframe even smaller and cramming in a larger engine. The original wingspan was shortened by nearly 5 feet to give Rare Bear its characteristic chubby profile. The stock 2,800 cubic inch, 2,250 horsepower radial engine was swapped with a souped-up 3,350 cubic inch powerplant. Some sources say that Rare Bear now packs 4,500 horsepower under the hood—a claim supported by the airplane’s bulging trophy case. Like its namesake, E-flite’s RC version of the Rare Bear stuffs ample power into a compact airframe. A high-output brushless motor system motivates this downsized doppelganger to triple-digit speeds. If speed is your thing, keep reading. Prepare the Bear The Rare Bear is available as a Plug-N-Play (PNP) model, or in the Bind-N-Fly (BNF) version reviewed here. The only difference is that the PNP model requires you to add a receiver, while the BNF version includes a Spektrum AR636A six-channel receiver. Both versions feature a prepainted Z-foam airframe, four metal-geared servos, and a complete power system. You will need to provide a 4S 3,300 mAh LiPo battery. I was impressed by the kit’s factory finish. The paint job on my version is clean and devoid of any obvious blemishes. The outer surface of the airframe is slightly bumpy because of the nature of the molded foam, yet I could find no defects and the ejector marks are hidden on inner surfaces. I also thought that the decals were well executed with good alignment and no wrinkles or bubbles. There is little work required to get the Rare Bear flight-ready and the only tool that you will need is a Phillips screwdriver. The first order of business is to install the two halves of the horizontal stabilizer while skewering them onto a carbon-fiber spar. Each half of the stabilizer is held in place with a single screw that threads into a fillet at the root. All control surfaces are actuated by factory-installed E-flite A320 servos. Those for the elevator and rudder are located in the mid-fuselage, while each aileron has a dedicated wing-mounted servo. I had to connect the pushrod clevis to the elevator control horn. All control linkages for the rudder and ailerons were already complete. The horns and clevises fit together with no binding or slop. Attaching the wing is similar to the method used for the horizontal stabilizer. Each wing half was placed over the carbon-fiber spar, which also passed through the fuselage. I routed the leads for the aileron servos into the radio bay of the fuselage and attached them to the included Y-harness. The wing panels were secured with four screws that are accessed through the removable canopy hatch. Speaking of the hatch, it is held in place with a lip on the front and strong magnets in the rear. A clear, flexible handle protrudes from the rear edge of the hatch to provide a gripping surface for removal. The handle works fine, but I didn’t like the looks of it on the otherwise clean profile of the Rare Bear. I found that I could disengage the magnets without damaging the foam by simply skewing the rear of the hatch to either side. After discovering this, I removed the unsightly handle. The included AR636A receiver was already glued into position with the leads from the ESC, rudder servo, and elevator servo plugged in. After installing the wings, I also attached the aileron Y harness to the receiver. I was able to tidy up the area by securing the servo leads with zip ties and routing the longer of the two antennae through a hole in a fuselage bulkhead (drilled using sharpened brass tubing). Before binding the receiver to my Spektrum DX8 transmitter, I removed the spinner and propeller as a safety precaution. Accidental propeller spin-ups in my workshop are no fun. The propeller required balancing anyway, so the removal effort was definitely worthwhile. The manual provides control throws for launching/landing (high rate) and normal flight (low rate). I was surprised by the small travel values suggested for the elevator (3mm and 5mm). It didn’t look adequate for a model of this size. Resist the urge to add more throw. My flight testing has proven the suggested values to be adequate. The AR636A receiver has built-in AS3X stabilization. Although AS3X won’t level the wings or save you from a crash, it makes the airplane fly smoother. The intent of AS3X stabilization is to minimize the effects of outside forces on the airplane’s flight path. Power for the Rare Bear comes from a 1,200 Kv outrunner motor spinning an 8 x 8 propeller. The motor is controlled by a 70-amp ESC, which also includes a BEC system to power the radio components. This system’s static amp draw is nearly 62 amps, so you must choose a battery that is capable of delivering that amount of current. I used E-flite’s recommended 4S 3,300 mAh battery with 50C discharge capability (part EFLB33004S50). A plastic tray is integrated into the airframe to serve as the battery mount. The battery is secured using a combination of self-adhesive hook-and-loop tape and hook-and-loop straps. I positioned the battery on the mount to achieve the suggested center of gravity location without adding any ballast. My power system measurements indicated that it produces more than 950 watts for this 2.8-pound airplane. That equates to a power loading of more than 300 watts per pound. Most sport models do well at approximately 100 watts/pound. Although I’d flown numerous high-performance models prior to the Rare Bear, none had a power loading this high. I wasn’t sure what to expect, but there was no doubt that it would be exciting! Flying the Rare Bear The flight-ready Rare Bear can be easily disassembled to fit back into its box. This feature came in handy when I decided to bring the model along on a family trip to Florida. My initial flights were made at the Flagler Radio Aero Modelers RC Club field in Bunnell. I appreciate the hospitality and support of the club members during my visit. Because the Rare Bear has no landing gear, it must be hand launched. A hand grip is molded into the bottom of the fuselage to make this task easier. Despite all of the power on tap, this airplane requires a good, strong throw into the wind. Anything less will result in a belly flop back onto the ground. All of my launches so far have relied on someone else to throw the airplane. I doubt that I will ever deviate from that trend. Having a measurable headwind significantly eases the burden on the launcher, but the launch is never a casual event. After the Rare Bear has reached flying speed, it becomes a more manageable airplane. It is predictable and easy to control—even if it is humming along briskly. The bright color scheme is easy to see and in-flight orientation has not been a problem for me. The stated goal of the Rare Bear is speed and it definitely delivers. During one of my flights, someone remarked how fast and smooth the model was. He was surprised to learn that I was flying at only half throttle! Does the model hit the 100+ mph speeds claimed by E-flite? I don’t know … I haven’t measured it, but I have no reason to doubt it. This stubby little chunk of foam can boogie! The Rare Bear does not get jittery or overly sensitive when flying at high speeds. Control response seems consistent throughout its normal speed range. The only difference that I’ve noticed so far is a tendency to wag its tail when carving through turns at high speeds. I can’t detect this behavior at moderate speeds. I don’t know how much the AS3X system influences the flying qualities of this model because the system is always active. All I can say is that the Rare Bear is predictable at all flying speeds. I’ve flown it on windless days and blustery days. To me, there is no difference in the pilot workload. I think that pilots who are comfortable with powerful four-channel sport aircraft can handle this model with no issues. Although casual high-speed flying is its forte, the Rare Bear has aerobatic chops, too. It is capable of basic four-channel aerobatics and looks its best when performing these maneuvers smoothly. Rolls are axial and inverted flight requires a touch of down-elevator. I find the high-rate control throws for elevator and aileron overly sensitive during normal flight. The suggested low-rate throws, however, are comfortable for me. I keep the rudder on high rates all of the time. This allows me to perform high-speed knife-edge passes down the length of the runway. Some fliers may like to keep the hammer down and zoom around the pylons with this airplane. Go ahead if that’s your thing, but be prepared for short flight times. The manual suggests setting a three-minute flight timer, which is about right for the velocity junkies. I find that I spend a lot of time flying the model at roughly half throttle. It moves along well at this power setting while leaving plenty of headroom for the occasional top-speed dash or tall loop. Using this power-management approach, I conservatively set my timer for six minutes and still land with reserve capacity in the battery. For landing, I switch back to high-rate throws. This airplane retains energy well, so you have to plan ahead to get it to the ground. Under normal conditions, I’ll chop the throttle during the downwind leg to set up for a midfield arrival. Conclusion If all-out speed is your goal, there are definitely RC models that are faster than the E-flite Rare Bear. This airplane is noteworthy for combining impressive speed with aerobatic capability. You get both of these characteristics in a package that is easy to assemble and not overly challenging to fly. Although the launch can be tricky at times, proper technique and a trusty helper can stack the odds in your favor. When the Rare Bear is in the air, it doesn’t take long to see how much fun you can have with a big motor and a little airplane.[dingbat]
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1 comments

hi you say nothing about gluing what type my stab was detach from shipping theres no hing?? what to put thanks

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