Flex Innovations RV-8 10E SUPER PNP

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Review
Flex Innovations RV-8 10E SUPER PNP
the rv 8 looks great on the ground and in the air
The RV-8 looks great on the ground and in the air and has an amazing level of aerobatic capability.
 

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I’VE SEEN FLEX INNOVATIONS products that a friend of mine has, so I had high expectations before this airplane even arrived. I like the RV series of full-scale airplanes and was glad to see this size of aircraft in model form. I’ve been a fan of using higher-cell-count battery packs as opposed to high-current setups, so this immediately spoke to me.

I was not disappointed when I opened the box and began unpacking the contents. Everything was perfectly protected and packed to withstand the roughest of deliveries. With a nicely printed manual in hand, I was ready to begin.

Assembly

Read the manual thoroughly ahead of time to familiarize yourself with the construction process and radio programming. You should also take a look at the company’s website to see if there have been any updates or revisions. The only addendum for mine, at the time, was for the ESC calibration. I downloaded the manual and addendum while waiting for the box to arrive so that I could familiarize myself with it before it got here.

Flex Innovations makes radio programming a no-brainer. There are charts in the manual for most popular radio brands, showing proper setups to work with the preinstalled and preprogrammed Aura 8 Advanced Flight Control System (AFCS). I did the programming while I waited for the model and it proved to be perfect when I installed my two Spektrum remote receivers to the Aura 8 AFCS. I suspect other brands of radios would be just as easy.

The landing gear is the first assembly step and is an ingenious design. The wheel pants are done in halves, making access to the axles, etc. super simple. I’ve never put together an airplane with pants done this way, but I wish others would follow their lead. Easy-peasy! The manual shows how to install the tail wheel and retention plate, but mine arrived preinstalled.

Installation of the vertical stabilizer is next and the only assembly requiring glue. Using the recommended 30-minute epoxy, this is the slowest step in the assembly process. Be sure to check and connect your lights if you get the night version before gluing the stabilizer in place. The usual precautions about making sure it’s vertical and true apply.

Slide the horizontal stabilizer halves over a joiner with a connector stub and socket on the elevators. Align all of them properly, plug in the lights (if applicable), and secure with one screw in each side.

At this point, you need to set up your radio and install the receiver. Flight modes are defined in the manual and preprogrammed into the AFCS. Options are available for advanced programming and expert pilots, but I recommend staying with the default setting until you’re sure you want to change. It can be changed back at any time, but it’s best to start at the beginning.

My one (minor) criticism is the order of the manual’s steps. It has you calibrate the throttle and ESC and listen to the audio tones from the motor. The problem is that the motor isn’t installed yet, so there are no sounds. I went ahead and installed the motor and returned to this step.

With your radio installed, you can go ahead and add the rudder and elevator linkages. This was a pleasant surprise because the manual showed Z-bends, but the company updated the linkages to ball joints on both ends. I suspect an addendum will address this eventually, but you’ll be pleasantly surprised.

The main wing halves slide onto a joiner and are retained with a single thumbscrew for each side. If your hands are too beefy to fit into the fuselage to tighten them, fear not. There is a Phillips-head on each one too. Once again, be sure to connect your lights if you have the night version. All control of the linkages are preconnected on the wing.

At this point, you can check your control surfaces and ensure that all of the gyro functions work as expected. Because you’re powering the radio with your motor’s battery, be sure to remove the propeller first! The programming and control functions worked like magic, with no changes on my part. Testing steps are thoroughly laid out in the manual, along with troubleshooting tips. I doubt that you’ll need them, but they’re there.

Control Throws and CG

There are two center of gravity (CG) locations listed. I started with the "sport" location of 199mm from the trailing edge (TE). Note that I wrote TE because that’s how they are measured. It makes sense because it’s much easier to lay a ruler on the flat, back edge and measure forward than it is to measure from the shaped leading edge. The "aerobatic" location is 195mm from the TE, so there isn’t a huge range, but you will feel it. Quique Somenzini designed this airplane and recommends the sport location, and I’m not one to argue with a world champion!

there are not a lot of pieces to assemble and everything arrived in good shape
There are not a lot of pieces to assemble and everything arrived in good shape.

Control throws aren’t listed and it’s not necessary because the correct settings are preprogrammed into the Aura 8 AFCS. The flight controller negates the need for dual rates, exponential, etc. Follow the manual settings and yours will be right. The three flight modes define everything—and you only need to assign the switch for them. From the manual:

Flight Mode 1: Sport (gyro off)

  • For general flight, test flights, or safety.
  • Rates are low and exponentials tuned for general flight.
  • Gyro gain is set to off.

Flight Mode 2: Sport (gyro on)

  • For general flight.
  • Rates are low and exponentials tuned for general flight.
  • Gyro is set to low.

Flight Mode 3: Advanced (gyro on)

  • For advanced aerobatic flight.
  • Rates are highest and exponentials are tuned for 3D flight.
  • Flaps are coupled with the ailerons for maximum roll rate and authority.
  • Gyro is set to moderately high.

I can assure you that Flight Mode 3 will get your attention. I suggest that you make sure you’re ready for that sort of 3D flying setup before trying it. Flight Mode 2 is the recommended mode for normal flying, and I found that it’s quite comfortable.

Flying

As fate would have it, when I finished the model, an ice storm hit North Carolina, so flying had to wait a few days. I made my test flight in Flight Mode 2, and then tried Flight Mode 1, which disables the gyro, but leaves everything else the same.

This mode is there in case you find something odd with your programming and need to disable it to land safely. Mine had no such anomalies, but I tried it without the gyro out of curiosity. The airplane flies well either way, but the mild gyro stabilization in Mode 2 is great to have, especially on a day when the wind gusted to nearly 20 mph.

I set a timer for the suggested 4 minutes initially and have since upped the time after seeing my usual flight times and battery usage. Adjust yours accordingly. After the usual control checks, I eased the throttle up and the taxi roll was uneventful, except for surprising me with how quickly the tail came up and the model left the ground. It was a rock-solid takeoff and climb.

the wheel pant and tire assembly is an innovative
The wheel pant and tire assembly is an innovative, two-part design for easy maintenance and assembly.
carefully slide the wing panel onto the joiner and connect the control plug
Carefully slide the wing panel onto the joiner and connect the control plug and LED before fully seating the panel. Take care not to pinch any wires. The wing is retained with a thumbscrew inside of the fuselage.
the motor is mounted onto the firewall and the wires are fed through the channel to the esc
The motor is mounted onto the firewall and the wires are fed through the channel to the ESC.

With a few laps around the field to get a feel for the controls, I was off to the races. I found that I wanted just a tad bit of left aileron trim. Upon landing, I used the Quick Set Procedure to update the AFCS with these settings then reset the trim levers on the transmitter to center. Had the changes been extensive, I would have made mechanical changes, but these were minor and easily done using Flex Innovation’s suggested procedure.

I’m sure Quique would be embarrassed if he heard me refer to my aerobatics as "3D," but they’re my version of it and I know my limits. My usual aerobatics are easily accomplished using Flight Mode 2 standard settings. Flight Mode 3 couples the flaps and ailerons for huge control throws, along with increasing the elevator and rudder throws.

When you decide to try Mode 3, get some altitude and be ready for it. It’s a lot of fun but not for beginners by any means. Also keep in mind that when you’re in 3D mode, you do not want to attempt high-speed passes. It will exhibit uncomfortable oscillations because the AFCS is not intended for high-speed runs at these gyro settings. Return to Mode 1 or 2 for high-speed passes. 3D is slow and precise.

The full aerobatic catalog is available to you and only limited by your abilities. The airplane will do them all! Rolls are axial, snaps are sharp, spins are predictable and easy to recover from, and power is there for hovering as well. In 3D mode, you can do little flips in the span of the aircraft’s own length. Facing into the wind, it also did so while barely moving forward. 3D mode is tuned so well that it’s hard to believe how stable it is while still being so aerobatic. What a hoot!

Second Opinion

When I do flight photos, I prefer to take them myself, which requires someone whom I trust to fly my new airplanes. My usual partner is Wayne Parish and I called upon him. He’s a former full-scale air show pilot and has experience flying the full-scale RV series. It seemed like the perfect pairing to have him there.

the night version of the rv 8 is impressively lit
The night version of the RV-8 is impressively lit to ensure that you can go flying any time of day or night.
there is tons of room inside the easily accessible fuselage
There is tons of room inside the easily accessible fuselage. The wires are tidy and secured. The wing-retaining thumbscrew can be seen in front of the radio tray.

I don’t know if I’ll ever get the grin off of his face. From the moment he flipped it into 3D mode, Wayne was impressed with all aspects of this airplane’s flight envelope and its precise handling.

Conclusion

I’ve wanted an airplane designed by Quique for some time and have watched the staff from Flex Innovations demonstrate them at events that I’ve covered. This was the right one for me to try and I couldn’t be happier. The lighting is excellent for night flying and the model showed me no bad habits.

Some might question the low mAh rating of the battery, but it’s more than sufficient. I wish more manufacturers would follow suit with higher cell counts and lower current. Its great sport-scale looks and superb performance make this RV-8 10E SUPER PNP my new favorite model!

 

By Greg Gimlick | maelectrics@gimlick.com

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