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ParkZone & Horizon Hobby's Ka-8 BNF Sailpane Review

In this review we get to see the Ka-8 sailplane fly using the new E-flite Hi-Start 450 to launch it as well as flying at the slope and with aerotow using the servoless release.



Wingspan: 88.6"
Weight: 27.7 oz.
Length: 41"
Servos: 5 servos installed
Transmitter: 4-5 channel minimum
Receiver: Spektrum 6 CH AR610 full range sport receiver
Battery: 7.4V 2S 1300mAh
Minimum Age: 14 recommended
Experience Level: Intermediate
Assembly Time: Less then 1 hour
Voltage Regulator: Allows use of Li-Po 2-cell battery
Manufacturer: ParkZone
Available From: ParkZone
Price Ka-8 BNF: $219.99 BNF
Price Ka-8 PNP: $159.99 PNP

My first love in Radio Control was pure sailplanes. I took bag lunches to work to save money to buy my first sailplane kits and a two channel radio back in the mid 70s and was taught how to fly by members of the South Bay Soaring Society. I spent many hours building sailplanes from kits as kits and scratch building were the only ways to get a new sailplane. A few years ago the Radian electric sailplane allowed me to just buy and fly and it proved to be an excellent flyer and confirmed to many how well foam sailplanes could fly. I have flights of over an hour at thermal sites after I turned off the Radian's motor. I even have equipped her with a number of LEDs for night flying.

Knowing how well the Radian flew, I was delighted to see ParkZone come out with the Ka-8 as a pure sailplane, made of foam. The Ka-8 can be launched with the new E-flite Hi-Start, tossed off the hill at the slope into the wind or towed up to altitude with a tow plane using the optional servoless payload release. I was about to purchase the plane when I got a chance to review her which I of course leaped at. As with most of you my first view of the Ka-8 was ParkZone/Horizon Hobby's promotional video of the Ka-8 which I have posted below. If that doesn't get you interested, than maybe sailplanes are not for you. However, If like me you like what you see, than enjoy the review. This is a sweet sailplane!

Ka-8 Sailplane BNF & PNP by ParkZone (2 min 3 sec)

Kit Contents BNF (Reviewed Model)

Kit Contents BNF

  • 2-piece 2.25 meter foam wing with ailerons and spoilers
  • Foam fuselage with rudder, elevator and spoiler servos with fixed main wheel
  • Wing joiner tube & Wing cover with screws
  • Decal sheet
  • Spektrum 6 channel AR610 sport receiver
  • 2S 7.4V 1300mAh Li-Po flight battery
  • E-flite 2-3 cell voltage regulator
  • Li-Po 2-cell charger
  • Instruction Manual

Kit Contents PNP

  • Same as above EXCEPT:
  • No battery pack
  • No voltage regulator
  • No Li-Po charger


  • Superb scale outline and detail
  • 2.25 meter wingspan
  • Two-piece wing design for easy transport
  • 4-channel control out of the box
  • Accepts E-flites servoless payload release for aerotow (EFLA405 - sold separately)
  • Requires a full range 4 channel DSM2/DSMX aircraft transmitter (5 channels required for servoless payload release)
  • Rudder, elevator, aileron and spoiler servos installed
  • Compatible with E-flite Hi-Start launch system (EFLA650 - sold separately)
  • Durable Z-Foam constuction
  • Fixed main wheel


  • Spektrum 6-channel sport receiver installed
  • 2S 7.4V 1300mAh Li-Po flight battery
  • E-flite 2-3-cell Li-Po voltage regulator
  • 2-cell Li-Po battery charger
  • Requires a full range 4+ channel DSM2/DSMX aircraft transmitter (5+ channels for optional tow release)

Other Items Horizon Hobby Supplied for the Review

Horizon Hobby also supplied

  • Servoless payload release (EFLA405)
  • E-flite Hi-Start system (EFLA650)

Author Supplied

  • JR 9-channel transmitter with sailplane programming
  • A screwdriver
  • Lead Ballast



The wing arrived fully assembled in two halves with the aileron servos installed and connected to the ailerons. There was a servo to control the flaps installed on one wing half. I only had to do final assembly of sliding a wing rod into the big empty hole in the wing root and then slide on the second half of the wing. I slipped the wing joiner cover into the holes for it on the top of the wing and held it temporarily in place. Placing the wing on a table or the ground at the field with the bottom of the wing facing up I slid the unattached spoiler clevis onto the servo arm and connected the clevis and slipped the rubber tubing up over the clevis to keep the parts connected. The wing was now ready to be attached to the fuselage or decals could be added. I went with the German decal option and placed the number on the bottom of one wing half and two black decals on the other side. I set the wing aside for attachment to the fuselage later.

His 001.jpg:The spoilers are pre-installed but I did need to adjust the clevis to have the spoilers rise and close together.


As purchased there was no assembly necessary for the fuselage. I attached the numbers to both sides of the fuselage and the German flag decals onto both sides of the vertical stabilizer. Normal assembly was complete except for installing the horizontal stabilizer and the wing. However I had the optional servoless payload release and installed it now.

Installing the Servoless Payload Release into the Fuselage

This process is really simple! I removed the two screws (both ends) holding the plastic red plate in place on the bottom nose of the fuselage. With the plate off I saw that the screw in the middle was securing a weight that just turned as I turned the screw. There was a notice on the weight to remove it to install the servoless payload release Herein after referred to as "Release."). Accordingly, I held the weight with one hand and removed the screw with a screwdriver that I supplied. In the fuselage there was a molded space for the Release. I snaked the control wire for the Release up into the cockpit area and slipped the release into place and secured it with two screws. The second piece of the Release was not used with the Ka-8. I reattached the red plastic cover plate with the two screws. I then plugged the Release into channel five of the receiver so it is controlled by the landing gear switch on my transmitter. To attach a tow line I put a small screw drive into the slot on the bottom covering plate and slid the bar back that pulls the pin back in the Release. Place the tow line loop into the opening the fuselage bottom and let the pin slide back forward into the holding position. It can be remotely opened when desired in the towing process.

Canopy Release

The Canopy is held in place with a foam tongue in the front and a latch in back. The canopy release button is flush with the top of the wing in the center front of the wing in the front of the wing saddle.


The horizontal stabilizer with attached elevators slide into place on the back of the fuselage and was secured in place with one screw. I then attached the clevis on the control rod coming out the back side of the fuselage to the control horn on the elevator. Done! To remove the stabilizer for transportation or storage just disconnect the clevis, remove the screw and slide the stabilizer out of the nest for it in the back of the fuselage.

Radio Installation

In the BNF version the six channel receiver came already installed. The sailplane itself requires a four channel transmitter controlling: ailerons, rudder, elevator and spoilers. I use the throttle control for the spoilers and it works great. The servoless payload release requires a fifth channel and I am using my JR 9303 which I use to control most of my sailplanes.

Powering the Radio System

I have the BNF version which comes with a voltage regulator and a two cell 7.4-volt LiPo battery to power the radio system. For those with the PNP version you can buy the voltage regulator and a LiPo battery separately but if you wanted those you would have probably bought the BNF version in the first place. I would use a small four or five cell NiMH or NiCad battery pack and I would be careful to keep the weight down in selecting the battery pack. An alternative would be to use a ESC with BEC or a stand alone BEC with a small LiPo battery pack. The voltage regulator weighs 19 grams and the recommended battery pack weighs 67.5 grams so there is 86.5 grams of weight to work with right there. I also added some lead to the nose of my Ka-8 so there is some extra weight to play with if you add nose weight to bring the C/G forward of the recommended balance point. Since I am still adjusting that I am not giving a final weight but it is at least 20 grams of lead.


I guided the aileron servo wires and the flap extension wire inside the fuselage back to the opening in the top of the wing saddle and used some needle nose wires to pull them up through the opening. I connected them to their respective wires from the wing and placed the wing in place on the fuselage. the cockpit release control near the front of the wing saddle goes through the wing and is flush with the plastic wing joining cover that fits over the wings center section. Three bolts were used to secure the wing cover and the wing to the fuselage.

I bound the receiver to my transmitter and found I had to reverse the servo direction for the ailerons, rudder and elevator. I have the throttle stick at the top for spoilers retracted and pull the stick down to deploy the spoilers. I had one spoiler going up before the other and going up higher when at the full stick movement. I removed the wing and got a 24" servo wire extension and temporarily connected it between the spoiler servo and the original extension wire for the spoiler. I adjusted the clevis on the wing half where the servo was not installed until the spoilers operated together and their deployment was equal.

Center of Gravity Balance and Control Surface Throws

The instructions gave the C/G point as being 72mm behind the wings leading edge. Fellow E-Zoners have recommended as far forward as 55mm. I like my balance fairly far back but still with good control so I compromised and started at 65mm back from the wings leading edge. That worked perfectly for me at the slope. It latter proved to be good for all types of flying. I obtained that balance by added a one ounce flat piece of metal to the nose area inside the fuselage and securing it there.

For the control surfaces the following throws were recommended and used by me in setting up my Ka-8. I found they worked well.

Control Surface Throws High and Low Rates

  • Aileron: 17mm up & 15mm down; 12mm up & 11mm down
  • Elevator: 16mm up and down; 11mm up and down
  • Rudder: 32mm left and right; 22mm left and right



The Ka-8 has four controls as discussed above. They are: aileron, rudder, elevator and spoilers. I found the elevator was very responsive, ailerons moderately responsive and rudder very effective. For gradual turns with a bit of a yaw the ailerons work fine by themselves. For a sharper turn the rudder and ailerons work well together. The spoilers are effective at slowing the Ka-8 down and bringing her down from altitude as well as a precision landing aid.

Flying at The Slope

At the slope I did my initial trim flight. I walked well behind the slope at Los Banos and tossed it forward with a firm level throw. It glided so well it surprised me and I had to deploy the spoilers or I would have flown out over the slope. The wind was light but she had no trouble staying up. I went for my first turn back towards the slope using just the ailerons and when she didn't turn fast enough to suit me I added some rudder throw and she whipped right around. I found using a combination of rudder and aileron gave me the control that I wanted. I am used to flying with both thumbs and felt no need to program in any mixing for flying at the slope but if your not used to using rudder for turns on the left stick programming in some mix would be a good idea. I added a few clicks of down trim on the elevator and my friend Charles Eaton took over the flying so I could shoot some stills and the slope video posted below. Charles found her to be a very nice handling sailplane and he gained quite a bit of altitude off of the breeze. He put in a few more clicks of down elevator and deployed the spoilers to bring her down. The spoilers were very effective at bringing her down but still keeping the sailplane in relatively level position. He performed the nice loop shown on the video. When I flew her again I later did a more extensive dive and pulled out a little to quickly and her wings rolled like a belly dancers stomach but there was no damage and she returned to normal flight. Charles landed for the video and came in right across the front of the slope. I have since made several slope landings by flying back behind the slope and deploying the spoilers landed on the flat ground as if it were a runway. I do like that wheel!

In my two outings to the slope for this review I have had spotty winds of about 5 miles per hour the first time and steady winds up to about 8 miles per hour the second time. She flies very nicely in low level wind. If the wind were any higher I would rather be flying a heavier more aerobatic plane designed for aerobatics or converted to the slope from a warbird. For nice scale looking flight the Ka-8 fits the bill very nicely.

ParkZone Ka-8 BNF Flying at the Slope (2 min 49 sec)


Flying With the E-flite Hi-Start launching System

Assembling and Storing the Hi-Start

I assembled the E-flite Hi-Start Launching System at the flying field. I took the end of the rubber tubing and tied the knot shown in the instruction manual around one of the two metal loops supplied with the kit. I pulled the rubber very tight to compress the knot and put the loop onto the hold down post. I pushed the post into the ground at approximately a 45 degree angle into the wind. I put the roll of string into one pocket and the parachute and separate free loop into my other front pocket and the handle for the reel into my hip pocket. I unrolled the rubber tubing away from the wind in as straight a line as I could. When I had unrolled all of the rubber tubing I stopped and tied the tubing onto the second round ring. I the tied the string onto that ring and continued my walk away from the wind. When I ran out of string I tied it to the ring that was securing the shroud lines from the supplied parachute. The Hi-Start was now assembled and ready to use. I went to a work table at the field and screwed on the handle to the Hi-Start reel with the three supplied screws. The handle went on the side opposite of the reel's center rod. It helps in rolling up the Hi-Start when done with it for the day.

Finishing the discussion about the Hi-Start let me cover how to roll it up at the end of the flying session. There is a plastic peg that helps hold the ring on the top of the parachute to the hub of the reel. I placed the ring on the peg and manually rolled some of the string over the parachute. I then switched to rolling the reel in my hands and walking back to where the Hi-Start was anchored to the ground. This has the parachute at the hub followed by the string and then the rubber over all of that. This way the Hi-Start is ready to be used next time starting always with the anchoring process and rolling the Hi-Start out away from any wind.

The sun is the enemy to rubber and this is very true for the rubber used in Hi-Starts. Roll up and store your Hi-Start out of the sunlight. Even if you are lucky enough to own your own meadow don't leave your Hi-Start out as it will shorten the life of the rubber tubing needlessly leaving it out in the sun when it is not being used.

First Launch

It was a perfect day for Winnie the Pooh as it was blustery. That is not perfect for launching a sailplane. I also had a limited amount of time to fly before leaving for a family gathering. The normal stretching of the rubber to Hi-Start the Ka-8 is from 120 to 150 feet per the instructions. However, the instructions also recommend shorter distances for windy conditions. Because of the windy conditions I only walked back about 80 feet for the first two launches. I hadn't done any extensive balancing of the sailplane with test glides and was still balanced at 65mm behind the leading edge of the wing. Although I was in front of the C/G recommended in the instruction manual I was still behind the balance point being recommended by many fellow Liftzone members. Before I toss my plane in the air this is a good time to discuss the effect of the balance point for those of you new to sailplanes. (This includes Radian pilots as well.)

Balancing The Ka-8

In my experience properly fine balancing a sailplane to your preference for flying is far more important than the fine balancing of a powered plane. If a sailplane is balanced nose heavy it will drop more in flight than it should. That gives her a poor glide ratio or requires up elevator to counter act the drop and that creates unnecessary drag. Nose heavy does make for a more stable sailplane that is easier for the pilot to control and one that tracks up a Hi-Start very nicely in calm conditions or into the wind. Moving the balance point back too far can make the sailplane tail heavy and possibly uncontrollable. On a sailplane that remains controllable but has a backward balance point the sailplane is more responsive to lift and can more readily telegraph to the pilot when lift has been encountered. It also gives a better glide ratio. On the other side of the coin it requires more skill to control the sailplane and avoid stalls and requires more pilot input (corrections) than normal when flying in a wind. It also doesn't track as well going up a Hi-Start or being pulled up with a winch. Tail heavy sailplanes will often fly back and forth across the sky as the pilot seeks to control the launch. My preference is to fly a sailplane balanced towards the back of the normal recommended balance area but one that still tracks up on a High-Start in a straight line. I usually start in the front or middle of the recommended balance area and move my way back to where I feel comfortable. With what I read in LiftZone I started ahead of the recommended instruction point for the C/G but not as far forward as many have been using as posted in LiftZone.


Ka-8 Short (1/2 stretch) Hi-Start launch into the wind at thermal site (1 min 45 sec)

Those first two launches were not very spectacular but I did control the Ka-8 and was able to land her over on the runway which was my goal. It was really to windy to fly without adding some ballast and I was pressed for time so that ended my first High-Start flying session. The next day was a Sunday and I got in four launches all into a breeze and I went back and stretched the rubber 120 feet. Because of the breeze they were all acceptable launches but not spectacular launches. Still I caught thermals on two of the launches and had one flight that lasted almost a half hour. The next weekend in Modesto to shoot a High-Start video and some stills I had my friend Jeff Hunter fly the Ka-8 for his first time. Jeff is an excellent pilot and a very skilled sailplane pilot. I had brought a variety of sizes of lead to have Jeff balance it where he thought best. Jeff was happy with how I had her balanced and after a couple of hand toss flights he was ready to put her up with the High-Start. We stretched out the line to the short distance recommended in the Ka-8 manual for normal conditions of 120 feet and while she tracked up nice and straight the launch was not all that it could be. The next launch we stretched it back to 135 feet and the height gained from the launch was significant but Jeff was quick to go to 150 feet for the third launch. Again she tracked up beautifully and this launch was easily the highest of the three. It was early in the morning and we weren't looking to soar, just shoot pictures but Jeff liked the way she handled and found the launch height from stretching the line back 150 feet acceptable as did I. Because of the lightness of the Ka-8 we weren't all that sure putting more strain on her by going back further would benefit us very much. After seeing the video of the launch I believe that 150 foot stretch is what I will stay with when launching my Ka-8.

Back home in Stockton I went to a big local park and laid out the High Start and did two launches at 120 feet feet and then ten at 150 feet. The ten at 150 feet were all nice launches. I caught a small thermal after the last launch and got a fifteen minute flight before I brought her back over the park and landed. I then got two aerotows from a friend but we didn't have a third person so no pictures. More on those flights below. The next day I decided to do five more launches with my E-flite High-Start. I had given it a detailed inspection when I rolled it up the previous day and it was still in perfect condition. These last five launches were on a calm morning and the launches were all acceptable. Simple straight tracking with the loop on the parachute falling off at the end of the launch.

My High-Start was still in perfect shape when I put her away. I have read that some LiftZone members have been breaking the rubber on their high starts. It certainly isn't due to the weight of the Ka-8 which is a very light sailplane. I think my High Start has remained in such good shape due to the wind conditions I started in and I broke my high start in with some weaker stretches. I didn't do this by plan, simply in response to the wind and following the directions that came with the Ka-8. If conditions with mu High-Start change I will report on that here as a follow-up to this review. So far everything is good with my E-flite 450 Launch System and I recommend starting with some shorter stretch launches to break in your high start.


Two Ka-8 High-Start Launches (1 min 55 sec)

Aerotowing the Ka-8

I have already discussed how to install the servoless payload release earlier in this review and I will describe it in use in a moment. But I want to share that there is another way for pilots to aerotow their Ka-8s to altitude and it only requires some string, a piece of cardboard and matching pieces of Velcro like material. Take 70 feet of string and secure one end to your tow plane at or near the back of the wing. Secure the other end to a piece of cardboard with one side of Velcro type material on it. Stick the other side of the Velcro like material just under the nose of your Ka-8 on the red plastic piece (It will remove the paint from the foam.) Stick the two pieces of Velcro together and have the tow plane pull your Ka-8 to altitude. Minimal movements on the controls of the Ka-8, especially elevator which will be more sensitive at towing speeds is required. Stay outside of the tow plane on turns and keep slack out of the tow line. When at altitude turn the Ka-8 away from the tow plane sharply with ailerons and rudder. The Velcro like material pulls apart and the Ka-8 is flying on its own. The cost is minimal. it works well but you have a patch of Velcro like material on the bottom side of your Ka-8. Doesn't look to bad if you have access to a red Velcro like material.

For a more classic looking tow I recommend using the optional servoless payload release. I pushed back the locking pin with a small flat blade screw with the little plastic piece on the side of the servoless release. Holding the pin back I slip in a circle of string on the end of the tow line and let the pin slide forward. The pin holds the loop on the end of the tow line. When you connect the battery to the converter the servoless release becomes active for one use. If I did a practice release I had to disconnect the battery pack and reconnect it to reset the release to work. It will work just once per set but it does pull the holding pin all the way in and has released every time.

When the Ka-8 is at altitude, or if it gets into trouble during the tow, I flip the gear switch on my transmitter and the bolt pulls back and releases the tow line. While being towed be ready to pop up the spoilers for just a moment if you start to catch up with the tow plane. Do not use them for any extended time. Avoid using them if you can while being towed. Stay above the tow plane and if you need to use down elevator use very little stick movement as the Ka-8 is more more responsive at the higher tow speed. When turning let the tow plane pull the Ka-8 into turns. If the tow plane is turning left be on the right side of the tow plane slightly. Be very aware of the prevailing breeze and don't let the Ka-8 get on the side the tow plane will turn as that will create slack. I only used ailerons slightly and that was to keep from going inside the line of the tow plane on some turns. The less stick movement on the transmitter for the Ka-8 during a tow the better. The Ka-8 with its dihedral tows very nicely. This is an excellent plane to perform your first tow. I have been towed by a Mentor and a Sensei and both worked well and didn't seem to be at all strained by the process and the tow planes flew just slightly above half throttle. Be sure to have the tow line above the horizontal stabilizer of the tow plane. If any problems are encountered hit the tow release switch.

Length of Tow Line

My first tows were using a friends tow line which was at least 1 1/2 times as long as the tow line supplied with the Ka-8. It also had some ribbons on it to make it easier to see when disconnected from the Ka-8. It worked great. I recommend a longer tow line then the one supplied with the plane. The video below was made using the supplied tow line.

Horizon Hobby's Ka-8 sailplane aerotow (1 min 2 sec)



Using the supplied tow line I had a friend fly the tow plane and another plane control mu Ka-8. There was a strong cross breeze and my instructions were not as clear to him as they should have been. The breeze blew the Ka-8 to the side where the tow plane turned and slack developed as the plane was turned a bit to sharply. When the slack was pulled out the Ka-8 flipped over and while upside down the Ka-8 hit the gear switch and the sailplane released from the tow line while inverted. The Tow plane landed without any trouble. The Ka-8 was brought to right side up and control was regained and she landed without any problems. My instructions were given in a hurry and were less than perfect to both pilots. Still everything turn out OK.

Aerobatics/Special Flight Performance

Soaring is the special performance looked for in the Ka-8. With a steady breeze up to 10 miles per hour a pilot can fly all day at the slope. At a thermal site a skilled pilot might be able to keep her up on a great day for a couple of hours and most sailplane pilots will be able to spot lift as she gives great thermal signals. When flying into a thermal her nose goes down, her tail goes up and she starts to rise with the air. Time to circle and ride the lift up into the sky. If I brush against the side of a thermal the wing touching the thermal is lifted and she turns away from the lift. Time to circle around and back into that thermal and start the climb in a banked circle. I move my circle down wind with the breeze to stay with the drifting thermal and break away from the thermal when she starts getting too far down wind.

As for aerobatics she does a nice if somewhat slow loop de loop. I am pretty sure she can do a sloppy sailplane aileron roll but I haven't tried one as I find the move rather unattractive and I have no interest in doing it. I have aerobatic sailplanes for the slope or electrics at the field for aerobatics. The Ka-8 is a true sailplane. She balances nicely as a sailplane should just as she comes in the box. She is an excellent flyer for light wind conditions at the slope, thermal site and with an aerotow. That is special to me. As a scale plane she is best considered a Sunday flier. A very nice and fun Sunday flier.

Is This For a Beginner?

ParkZone says it is not recommended for children under the age 14. I leave that up to the parents if they are working with their child in teaching him/her to fly RC. I have used the Gentle Lady 2-channel sailplane to teach a number of Boy Scouts to fly RC using both a high-start and at the slope. I have no problem recommending a two channel sailplane with elevator and rudder control to a beginner especially working with an instructor. The Ka-8 being a full house sailplane I would recommend it for a second plane for a person teaching themselves. With an in-person instructor a beginner can learn with it but it is not my first choice for a Beginner.

RC Groups' Member Joespeeder's Photos From The Slope

This first collection of pictures is posted thanks to RC Group member Joespeeder, AKA Joseph Fialka. They were taken of his ParkZone Ka-8 at Sleeping Bear Nation Park at Pyramid Point. I want to thank Joe for sharing his photos with all of us.

Mike's Photo & Video Gallery

First Flight: A Trip to Los Banos to Slope Soar

Flying With A High-Start

Aerotowing The Ka-8 Pictures From RC Groups' Member: Charlie The Crow

The following pictures are posted with the permission of Charlie the Crow who flies at Sea World Field in the San Diego area. Charlie the Crow who is AKA Norm Arndt was flying the Ka-8 sailplane. The Mentor tow plane was piloted by Bob Stinson and the photographer was Vince Gonsowski. Thanks guys for sharing your talents here in RC Groups.

Author's Ka-8 Aerotow


ParkZone really got it right with the Ka-8 Sailplane! It is a triple threat scale sailplane as she flies well at the slope, the thermal field using a High-Start or being aerotowed and using the servoless payload release. She is basically ready to fly right out of the box. I needed to make a minor adjustment to the spoiler clevis on one side to balance their deployment and closing and added a little lead to the nose to balance her to my liking (exactly 1 ounce). As discussed above I added the servoless payload release that was provided for the review and that took about 15 minutes to install. As discussed above she gives great tells when thermals are encountered, probably because she is such a light sailplane over all that she is especially responsive when encountering lift either straight on or on the side. I am very happy to have had the opportunity to review the Ka-8 as I love nice sailplanes and the Ka-8 looks and flies very nice indeed.

Pluses & Minuses


  • Very nice appearance
  • Easy to assemble at the field
  • Easy to store and transport
  • Flies nicely in a 5-10 mph breeze at the slope
  • Tracks up a High-Start nice and straight
  • Gives great tells when lift is encountered
  • Very effective rudder, nice control with mixed aileron/rudder
  • Ailerons alone hold her nicely in a climbing turn position in a thermal
  • Very affordable


  • Not ideal for flying in wind much above 10 miles per hour
  • A longer tow line for aerotowing is recommended by this reviewer.


My Thanks to JoeSpeeder and Charlie the Crow for permission to share pictures of the Ka-8s. My thanks to Chris, Jeff, Charles, Pierce and Richard with help in flying, launching or towing and getting media for this review. My thanks to Horizon Hobby and ParkZone for supplying RC Groups with the Ka-8, the servoless payload release and the E-flite 450 Launch System High-Start for this review. Finally thanks to our editor, Angela, for editing this article.

Last edited by Michael Heer; Nov 14, 2013 at 02:48 PM..
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Old Nov 15, 2013, 06:30 AM
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Space reserved for possible updates. Mike H
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Old Nov 15, 2013, 01:33 PM
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Great review! Thanks for posting.

I see this wonderful vintage sailplane being another addition to my hangar.
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Old Nov 15, 2013, 02:12 PM
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Nice to see this review. This was an impulse buy at the LHS and I'm having a blast with mine, towing it up with a Fun Cub. I haven't had it out as much as I would like due to lack of a tow pilot, but the few times I have I've had good some good thermal flights. Flies like a gas bag. It's not so hot on a hi-start, as the wheel is about where the hook should be.

I made my own tow release with a small servo I had laying around, works like a champ.

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Old Nov 16, 2013, 02:51 PM
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I'd be interested in comparisons with the Radian and Radian Pro for soaring capability.
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Old Nov 16, 2013, 06:43 PM
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Looks great. I just saw two of these at kite Hill slope this morning. I want one.

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Old Nov 16, 2013, 09:57 PM
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Fantastic review! My first comment on a review, so just shows my opinion.

You did the best job I have seen yet with photos. Most relevant and clear pictures I have seen to date. Awesome sequence shots too. And good variety of flying shots plus video! Have been in the hobby 20 years and have yet to see a review done as well as you have.

I hope you do some more reviews.

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Old Nov 17, 2013, 08:14 PM
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Very excellent review !

After the third read I have just placed my order ! ( review is compelling ! )

This Ka-8 is actually perfect for my next project...which consists of one Big Lazy Ace biplane carrying the Bird of Time "piggy-back" and simultaneously towing the Ka-8....
I have flown two on my own simultaneously but for this project will split the piloting (just in case)

The BOT carries a video camera so will try for aerial shots of the Ka-8...!
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Old Nov 25, 2013, 08:57 PM
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Brilliant review, Michael: a lot of work! There's nothing like a beautiful scale sailplane for aesthetic satisfaction. This seems like a really good one to learn to aero-tow with.
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Old Dec 03, 2013, 06:11 PM
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Posted this in the Fun Cub thread earlier: Had the cub out as a tow plane today doing some aerotow with my KA-8. Fun stuff, and working great until I hit the wrong switch and dropped the tow line in the trees. Robin and I each had a good thermal flight with the KA-8. It is more challenging than you might think towing a glider, but fun whether you're driving or flying.

The KA-8 flys pretty good for the funky bit of beer cooler it is. Maybe not as good as the standard Radian and I don't have much time on a Radian Pro, but probably more like it. It's a bit of a gas bag, and the wings flop up and down, but it looks good in the air and is different from anything else I fly. I don't have an aileron-rudder mix set up, and it seems to need a fair amount of rudder to get a coordinated turn, but I managed to take it out from tree-top height. Aerotow is a challenge, we haven't mastered it yet, but we're having fun trying. I see bigger in my future
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Old Dec 16, 2013, 11:13 AM
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Hello, After reading your review on the Parkzone Ka-8 you say the model flies well in winds of no more than 5 to 10 mph. Made me think of my instructions to my Multiplex Easyglider were they tell you if the plane needs more ballast to slip a 5/16 metel rod inside the hollow wing spar as needed. They note that it is the perfect spot because it does not change the balance point much if any.
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Old Dec 19, 2013, 04:43 PM
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I now have the KA-8. Very nice. I purchased a Castle BEC, and that will allow me to use a good size battery to balance: battery+BEC up to 117gms if I'm calculating correctly. I'll report back when I've flown it!
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Old Jan 12, 2014, 07:32 PM
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Just had my first weekend of flying with the KA -8. So much fun I just kept doing it again and again and again while my poor Habu 2 EDF jet sat in the car.

I had previously tried the UMX glider for high start and aerotow. It was nice and at $49.99, it was an easy purchase but I held off for something bigger. Radian flies great but I replaced it with a Radian Pro for more aggressive flying.

We were going to tow it up with a Quadcopter but since I just picked up a pretty powerful Vaterra Halix (monster truck with 3S battery), we tried some ground tows with the truck. It was so much fun and entertaining to get the glider up this way.

Next we tried to tow it up with a SuperCub that was upgraded to brushless. Tow pilot went into a stall right on take off and I had to release. Both planes went up about 15' and right back down. Tow pilot is going to keep practicing a level take off.

I set up a hi start with 200' of bungee cord and that got me up quick and long enough to enjoy, Then adding some line to the end got me up even higher. I probably had about 200' of line added and that's when the fun began as it kept going higher and higher. Longest flight so far is 4 mins.

I think it will go better tomorrow when I shorten the bungee and extend the line. I could see the glider wanting to fly higher up but the weight of the bungee and getting caught on grass made for a quick increase in altitude right after it releases up there.

I had about three close calls downwind when I thought it was gone from flying to low and slow but I put the nose down and full rudder over to make for a surprising quick turn before landing. Just gotta keep those wings level and going full throttle doesn't work.

The Sailplane programming really is different and I changed things around to act more like a powered sail plane (Radian Pro). Biggest difference is moving the Air brakes to a switch instead of throttle.

Lots of pilots came out to give me tips. I may have inspired others to dust off their sailplanes and come and use my hi start.
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Old Jan 16, 2014, 11:07 AM
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I purchased mine last summer from a buddy after he flew it a few times. He had towed it behind a glow powered Super Senior, a Kadet Sr clone. I had it towed up behind my electric LT-25 which has far more power than needed to tow this plane.

It flies very nice and about the only thing I don't care for is the wing likes to be in one piece and that makes it a bit harder to transport. It is only my second aerotow plane, the first being a Calypso that I put together with a tow release instead of a motor.
Aerotowing the Parkzone Ka-8 (3 min 33 sec)
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Old Oct 10, 2014, 10:23 AM
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Bringing this review thread back to life....

If you need a push to get this plane - now is the time! First it is clearance priced at $129.99 for the BNF model and right now you can get $20 off here in the US and free shipping. Just got one for $109.99 shipped to my door!

Fantastic deal!

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