Written by Terry Dunn
Blue Angels or U.S. Navy Reserve—you decide
As seen in the April 2017 issue of Model Aviation.
Type: Electric warbird ARF
Wingspan: 47.2 inches
Wing area: 451 square inches
Length: 36.5 inches
Radio: Futaba 14SG 2.4 GHz transmitter; Futaba R617FS receiver; four 9-gram servos (included); two 9-gram metal gear servos (included)
Needed to complete: Minimum six-channel radio; four-cell 2,500 to 4,000 mAh LiPo battery; basic assembly tools
Minimal flying area: Club field
Power system: 580 Kv outrunner brushless motor (included);12 x 7 four-blade propeller (included); 60-amp ESC (included); Admiral Pro 3,600 mAh 4S 50C LiPo battery; FlightPower 4S 3,350 mAh 30C LiPo battery
Power output: 35.2 amps; 507 watts
Flying weight: 4.3 pounds
Flight time: 7-plus minutes
Wing loading: 22.2 ounces per square foot
• Excellent kit quality
• No-stress warbird flying
• Multiple decal sets included
• Unclear instructions
• Some slop in wing control surfaces
Grumman’s F8F Bearcat was the ultimate embodiment of the “big engine, little airplane” design philosophy. It used the same 2,800-cubic-inch radial engine as its predecessor, the F6F Hellcat, but the Bearcat was smaller and 30% lighter. You can imagine how those factors influenced the younger feline’s performance.
Unfortunately, the F8F was a victim of poor timing. It entered service slightly too late to find fame during World War II. After the war, it was quickly overshadowed by the first generation of jet fighters.
The Bearcat’s time in frontline U.S. Navy and Marine squadrons lasted only a few years, but the design did serve some of our allies into the late 1950s. Perhaps the Bearcat’s most enduring legacy can be found in air racing circles, where the stubby fighter has always been a strong contender.
FlightLineRC’s rendition of the Bearcat is a 1,200mm wingspan model constructed of molded foam. All of the servos, electric retracts, and power system components are included and factory installed. You only have to add a six-plus-channel radio system and a four-cell LiPo battery of 2,500 to 4,000 mAh capacity.
Assembling the Bearcat
The mold quality of the foam parts in my example is good, with a smooth surface texture, clean recessed panel lines, and no blemishes. The model comes painted in an overall coat of dark blue. You’re not stuck with only one livery choice. Multiple sets of vinyl decals are included in the kit. Others are available from custom decal vendor Callie Graphics. You don’t have to worry about a flightline full of identical cookie-cutter Bearcats at your club.
Multiple sets of self-adhesive vinyl markings are included.
I noticed a few touches that are not normally found on ARFs. First of all, the cockpit features a prepainted pilot bust, simulated gauges, and seat details. I was most impressed, however, by the landing gear wells that were painted in a zinc chromate color. The landing gear also features inner and outer doors, as well as painted strut covers.
FlightLineRC includes a multilingual assembly manual. It contains everything you need to know to build the airplane; however, the manual also has many extraneous steps that cover tasks that were performed at the factory. You have to sift through these steps to find the information you need.
All of the parts mate together well. The wing-fuselage joints were a tight fit, but I was able to work things into place without too much trouble.
Each wing panel has two preinstalled servos for actuating the flaps and ailerons. When installing the pushrods for these surfaces, I noticed that the outermost hole of every control horn was a slightly larger diameter than the others. This caused a sloppy interface with the pushrod clevises. I used the middle hole on the ailerons, which was a perfect fit. I used the outer hole for flaps and the resulting play has not caused any issues.
I was initially concerned that the stock pushrods and clevises seem undersized for a model of this girth and performance. They are more like something that you would normally find in a lightweight park flyer, yet, after dozens of flights, everything is holding up fine.
The kit contains a small device called a control board. Its purpose is to consolidate the servo leads coming from each wing. You could omit the control board, but you would need to add three Y cables for the ailerons, flaps, and retracts. I used the control board on my model.
I installed a Futaba R617FS seven-channel receiver and linked it to my Futaba 14SG transmitter. I made a shelf for the receiver and control box using a scrap piece of sheet plastic. The plastic is glued into place just behind the battery tray. The receiver and control box attach using self-adhesive hook-and-loop tape.
The stock power system for the Bearcat includes a 540 Kv brushless motor, 60-amp ESC, and a 12 x 7 four-blade propeller. The propeller must be assembled, but it goes together easily. I was surprised that the propeller did not require balancing and it ran smoothly.
Removing the battery tray provides better access to the rudder servo, elevator servo, and ESC. A plastic shelf was added to mount the receiver and control box that helps to consolidate servo wires.
Access to the battery tray and radio gear is provided via a magnetically secured hatch just forward of the canopy. The elevator servo, rudder servo, and ESC are located below a plywood battery tray. The servos are accessible with the tray in place; however, the tray is easy to remove and its absence makes servo adjustments much easier.
The battery is secured in place with a meaty hook-and-loop strap. A swatch of rubbery nonslip material is provided to keep the battery from sliding fore and aft. I tacked the swatch to the plywood tray using a small dab of Goop adhesive on each corner. The overall retention system works great and battery removal is much easier compared with my usual method of using hook-and-loop tape between the battery and airframe.
The battery is held in position with a stout hook-and-loop strap. Nonslip material on the battery tray keeps the battery from sliding fore or aft.
Another scale feature of the Bearcat is a set of faux 20mm cannon barrels that can be inserted into the wing. They look great, but I was convinced that I would quickly break them if they were glued into place. I was also concerned that they would fall out and get lost if I didn’t secure them somehow.
I solved this dilemma by gluing 1/8-inch diameter disc magnets to the inside end of each barrel using thick CA glue. I also glued a mating magnet to the base of each socket in the wing. This allows me to install the barrels at the field and pop them back out for storage and transport. Two additional magnets glued to the underside of the battery hatch provide a convenient place to stow the dismounted barrels.
I glued small disc magnets to the plastic cannon barrels to make them removable.
There are no instructions for applying the vinyl markings. It is a time-consuming process, but easy to do. Rough cut the selected decal and remove only the paper backing. With the decal still attached to the clear top sheet, apply the self-adhesive vinyl to the model. When the decal is in place, you can peel away the clear cover sheet. You’re left with semigloss markings that conform well to compound curves.
The manual provides suggested throws for all of the control surfaces. Aileron and flap movement posed no problems. In order to get the indicated amount of high-rate throw on the rudder and elevator, I moved the clevises to the inner location on their respective control horns. I also increased servo travel using the dual-rate menu on the Futaba 14SG transmitter (125% for rudder; 135% for elevator).
I originally set up my Bearcat to fly with a FlightPower 4S 3,350 30C LiPo battery. With this battery fully forward, I had to add 1.5 ounces of ballast to the front lip of the cowling to get the indicated center of gravity (CG).
I have since flown with batteries ranging in capacity from 3,000 mAh to 5,000 mAh. All of them worked well. When using the larger packs, I locate them slightly rearward to maintain the same CG.
Flying the Bearcat
Some warbirds can be a handful to get off of the ground, so I steeled myself for a tricky maiden flight takeoff roll. The actual departure turned out to be a nonevent. I gradually added power. The Bearcat required little rudder correction and it quickly reached flying speed. All of my subsequent takeoffs have been similarly easy.
Retracting the landing gear significantly cleans up the Bearcat’s profile. The gear quickly cycles up and down. One of the spring-loaded inner gear doors on my unit sometimes fails to close completely. This issue only occurs in flight, so I suspect that aerodynamic forces are at play.
The electric retracts feature inner and outer doors as well as strut covers. The landing gear wells are factory painted.
The model’s power system produces a respectable top speed and strong climbs. Vertical maneuvers and loops can be as tall as you want. I spend much of my flight time at 1/2 to 3/4 throttle. For those of you who just like to go fast, MotionRC offers an uprated power system for the Bearcat.
High-rate control throws can produce quick rolls and snap maneuvers. That stuff is fun to do, but it isn’t very warbird-like. I usually prefer flying with low rates. The Bearcat is still capable of all four-channel aerobatics, but it is easier to make the maneuvers large and smooth.
Rudder use comes with a little bit of roll coupling. Keep this in mind when performing wingovers and stall turns. The Bearcat will fly knife-edge maneuvers, but it requires plenty of power, heavy rudder, and a little opposite aileron pressure to keep the wings vertical.
In-flight orientation is often a problem with models painted in dark, solid colors, and this Bearcat is no exception. You have to keep your eyes on it! The primary reason why I chose the color scheme that I did was the visual benefit of its broad orange fuselage stripe. Keep this in mind when choosing how to finish your Bearcat.
High-rate control throws make the Bearcat sporty, but it looks best when performing large, smooth maneuvers on low rates.
When flying with the 3,350 mAh battery, I set my timer for 7 minutes. There is often plenty of capacity remaining when I land. Those of you who always fly your warbirds at maximum military power should aim for 5-minute sorties. With a 5,000 mAh battery onboard, I can comfortably log 10-minute flights.
Although the Bearcat does not require flaps for easy landings, they do help to slow the model. Dropping half flaps causes a significant increase in drag, but no discernable pitch change. Even the full-flap setting creates only a slight nose-up attitude. Just be sure to mind the throttle when using flaps so that you don’t get too slow.
The full-scale F8F had so little propeller clearance that three-point landings were mandatory. This model has more breathing room, so you can touch down on just the main wheels if you prefer. Either technique works fine with this Bearcat. The only challenge with landing is managing the rudder and tail wheel to keep your rollout straight.
There is not much provision to route cooling air for the power system components. My test flying thus far has been in cooler winter temperatures, and I have not experienced any heating issues. I’ll be sure to keep an eye on things as warmer weather approaches. I’ll expand the air inlets and outlet if necessary.
The F8F Bearcat was one of the most capable piston-engine fighters ever built. For some, that could make owning and flying a downsized version slightly intimidating. There is no need to worry with the FlightLineRC Bearcat. Any pilot who is comfortable with a four-channel sport model should have no trouble stepping up to this warbird.
This Bearcat has a great scale profile and a number of factory-installed scale-enhancing features. It looks pretty good as is, but it could also serve as a great starting point for modelers who enjoy adding extra details and personal touches to their airplanes.