Ritewing Drak - RCGroups Review

Join Editor Matt Gunn as he builds and flies this monster FPV machine, the Ritewing Drak!

Ritewing Drak FPV Review

A Performance FPV Platform From the Makers of the Zephyr

Product:Ritewing Drak
Retail price:$349.99
Wingspan:60"
All-up flying weight:7 lbs
Construction:EPP and corrugated plastic
Optional Motor:Ritewing 3515 950kv
Optional ESC:Ritewing 85A
Prop used:APC 11x7e
Battery:Ritewing 5s 8000mAh 25c
Flight Controlled used:Eagle Tree Vector
Where to buy:ReadyMadeRC, GetFPV, Email Ritewing

This month, seven years ago, I built my very first FPV aircraft. Armed with nothing more than the information found on RCGroups of a budding niche in the rc hobby, I cobbled together a flying wing. The VTx of choice was 900mHz, and the DX201 was the best camera available. My first flights were full of static and interference from the linear rubber duck antenna and the less-than-optimal wiring job (circular polarized antennas were not yet available), but the flying wing I had built performed flawlessly - it was the Ritewing Zephyr. Chris Klick, the owner of Ritewing, had been manufacturing EPP and EPOR line-of-sight wing kits until introducing the Zephyr in the middle of 2009. It was designed to be a heavy-lifter, capable of hauling up FPV gear with a thick airfoil and 60" wingspan. As the years rolled on, the Zephyr line expanded to see tweaks in the airfoil, foam type, and airframe design - and I owned every version!

When Chris introduced a brand new airframe - one that would see a total overhaul of the Ritewing Zephyr build steps I had grown accustomed to - I knew I had to own it. The brand new design was the Ritewing Drak. The Drak is a far departure from the Zephyr as it features a swept-forward wing and large central fuselage. The foam has been upgraded to a smooth and durable EPP, and most importantly, doesn't require lamination, which saves many hours during assembly.

In this review, I'll build the Drak, set it up with an Eagle Tree Vector, and show you how well this FPV dragon flies across it's wide flight envelope. I'll touch on the majority of the assembly steps and show you how I got the Drak dialed in. Finally, I'll show you how easy it is to launch, fly, and land. Let's get started.

Review Video

The Ritewing Drak - RCGroups.com Review (18 min 56 sec)

What's Included - Fit and Finish

The assembly process has been streamlined with the Drak, and we'll go over how quickly it builds shortly. First, let's take a look at everything that's included. As I stated in the introduction, the Drak is made of high-quality EPP foam. Electronics bays, servo pockets, and spar channels are molded in, effectively eliminating the need for surgery with a hobby knife. NACA ducts have also been molded into the top and bottom of the fuselage; they pull cool air in and scavenge the hot air out the bottom. Unlike previous Ritewing kits, the elevons on the Drak are EPP. Alone, they are flimsy and not up to the task of controlling this monster, but once you embed the included fiberglass spars and iron on the laminate, they become just as stiff as wood elevons and are the perfect compliment to the EPP airframe.

A large EPP plug is included that fits in the nose of the Drak. It can serve multiple purposes or it can be removed completely. I decided to hack it up and create a snug-fitting battery tray for the Ritewing 5s 8000mAh LiPo. Keep in mind that since the front compartment will be covered with a corrugated-plastic lid, there's no real advantage to using the plug except for cutting it up and creating a battery holder or down-facing camera compartment.

The wings are very unique and do a great job of defining the omnious look of the Drak; I've found that the few times I took it to an AMA field for test flights, the Drak always gathered a crowd. Each wing has a recessed pocket for a full-sized servo, spar slots on the bottom, and smaller support spar channels on the top and bottom.

Stiff corrugated-plastic is the other main component of the Drak; it makes up the covers for all the electronics bays, the winglets, and verticals. All the holes and slots are precut and ready for installation, but if you run your VTx and LRS antennas out on the wings, you may need to cut a few more holes to let the wiring pass through.

A bundle of fiberglass and carbon fiber spars are included with the Drak. The larger carbon tubes comprise the main spars, and the thin fiberglass rods add structural rigidity throughout the airframe. Ritewing has always used the fiberglass rod method for making their wings stronger, and the Drak is no exception.

A generous package of goodies is included with the Ritewing Drak. The motor mount and fasteners, a hardware package containing everything to secure the corrugated-plastic covers, hook and loop tape to secure the wings (we'll go over that in a bit), and iron-on laminate rounds out the included accessories. Optional accessories are a plastic nose cover and plastic plates that mount in the floors of each electronics bay. I chose not to run either of these two accessories to save weight.

The Secret Sauce Combo

Since the introduction of the Zephyr Z3 Spade, Ritewing has been offering a motor and esc combo that are matched well to the airframe, and dubbed the "Secret Sauce". The Drak SS combo is an 85A esc and a powerful 3515 950kv motor. The motor is more-than-capable of providing unlimited vertical performance for the Drak with the recommended 11x7 APC prop attached to it. And with an observed amp draw of around 60A, the 85A esc has no problems staying cool in flight.

The Build

There are four types of adhesives used to assemble the Drak. Goop is the primary glue used, followed by a mixture of Gorilla glue and white glue (think Elmer's) for the main spars, and finally hot glue is used to tack down the fiberglass rods and secure the hook and loop tape under the wings. There is no assembly manual, but rather a series of videos created by Ritewing owner Chris Klick. I'll cover the majority of the assembly steps and also link to his videos in case you need further assistance. But with the build being as easy as it is, I don't think you're going to have any problems getting the Drak ready for it's maiden flight.

To install the motor mount, start by scuffing the foam on the fuselage and the motor mount cover with sand paper. What you're doing is removing the sheen from the surface so the glue can bond easier with the foam. The EPP foam is very smooth, with an almost waxy feel to it; removing that top layer assures your items will stick together permanently. With the surfaces ready, apply some Goop to the motor mount plate and a little to the fuselage as well. Press the plate in, then apply a little more to the foam plate cover and press it down. You can use clamps to sandwich the pieces together.

As I stated earlier, fiberglass rods are used throughout the airframe to increase it's structural rigidity. Let's start with the fuselage and install the two top and two bottom rods. Just like the motor plate installation, sand the spar channels to remove the sheen, and also lightly scuff the rods as well. Tack town the entire rod in each channel with hot glue. You don't need much, just enough to keep it flat inside the channel. I tacked it down every 6 inches, and a little more where the fuselage channels bend in the middle and back at the motor plate. With the rods in place, use Goop to fill the channel by squeezing it straight down on the channel and moving from the front, all the way to the back. Use a playing card to wipe the excess Goop off the fuselage and make a nice, flat surface.

This task will be repeated many times throughout the build: four times on the fuselage, eight times on the wings, and four times on the elevons. By the time you finish the last one, you'll be a pro! Just make sure to wear gloves and apply the Goop in a well-ventilated area.

There are four carbon tubes included with the Drak: two large-diameter sleeves, and two small-diameter spars. The sleeves get embedded permanently in the fuselage and wings, with the longer sleeve up front and the shorter sleeve in the aft slot. You'll need to cut each sleeve into three pieces. Let's start with the rear sleeve, so find the shorter one and place it in the rear spar slot. Push it all the way into the wing until it stops, then use some painters tape to mark the end where it exits the wing. Cut it off, them move over to the other wing and repeat. You will now have three pieces: one for each wing and a longer one for the fuselage. Repeat this process for the longer front sleeve. Now it's time to glue the sleeves in.

With the sleeves cut to fit in each wing and the center section, lay a thin bead of Goop in the bottom of each channel. Lightly scuff the sleeves with sandpaper, place a little painters tape over the ends of the sleeves (this is so the expanding Gorilla glue wont enter the tube from the inside) and then press them into the glue. Then add some more Goop above the sleeves where they contact the foam.

Now it's time to install the spar covers. Mix up some Gorilla glue and a little white glue (just barely cover the bottom of a small mixing cup with the white glue) and pour in into the channels. Quickly lay a bead of Goop on the sides of the spar channel, followed by a line of hot glue, and press in the spar cover. What we've done is apply three types of glue, each one doing something different: the Goop is the main structural bond for the sleeves and the spar covers. The Gorilla glue expands inside to fill any gaps between the carbon sleeve and the spar cover. Finally, the hot glue is meant to quickly secure the foam spar cover to the fuselage, preventing the expanding Gorilla glue from pushing it up. Phew! We did it!

The elevons are finished by first gluing in a fiberglass rod on the top and bottom with Goop, then covering the entire elevon with the included iron-on laminate. I used two layers of the lam for added strength. Once the elevons are sparred and lammed, they are quite strong and resist flexing very well. With the elevons ready for installation, you will need to prep the wings for the tape hinges, since the shiny surface of the wings won't hold tape well. I laminated the trailing edge of the wing, only as far up as the rear fiberglass rod; the laminate provides a good surface for the tape to stick to. To attach the elevons to the wings, I used standard clear packing tape.

Chris Klick does a great job of explaining the hinging method, so I'll post the video below that details his method:

Hinging (15 min 19 sec)

Installing Electronics

For this build, I chose the Xpert RC SI-4431 aluminum case “High Torque” brushless servo for each elevon. With a speed of 0.10 sec/60-degrees at 4.8v, and 194.93 oz-in of torque, the SI-4431 is fast, powerful, and very reliable. Mounting the servos was a painless process; I placed a few small blobs of Goop in the bottom of the servo bays, and pressed them in place. But before I mounted them, I centered the servo and installed the servo horn.

There are countless places on an airframe to mount your video transmitter and LRS antenna (assuming you're using an LRS). bays are provided on the center fuselage for these components, but I decided to make the most of the Drak's 60" wingspan and mount the VTx way out on the wing. I carved a pocket for the VTx to reside, then cut the fiberglass rod channel deeper, so the wiring could be routed under the fiberglass rod and into the center bay. The VTx is a ReadyMadeRC 600mw 1.2GHz, and my antenna of choice is the DragonLink 1.2GHz dipole. On the opposite wing, I mounted the DragonLink 433mHz dipole and also routed it under the fiberglass rod channel.

There's plenty of room inside the main bay to install your flight electronics, and I chose to run the Eagle Tree Vector for obvious reasons. The Vector not only offers a wealth of flight information in it's robust heads-up-display, but it also provides multiple levels of stabilization and flight control, adjustable at the transmitter during flight. For a full Vector installation article, click here.

The center of gravity on the Drak is very critical, as a tail heavy flying-wing will not fly at all. With that said, I cut up the EPP plug for the front bay and made a battery compartment that hold the 5s 8000mAh LiPo securely in place. I then moved it until the Drak balances slightly nose heavy and glued it in place with Goop. Keep in mind that you only need a few dabs of Goop to secure it in place, allowing you to easily remove it and reposition the battery if your payloads change in the future.

CG Measurement

The center of gravity is measured from the front edge of the front spar, forward 1.25 - 1.5". Measure from the front edge of the spar channel cover. I setup my Drak at 1.25", which allowed for all-around great flight performance and slower landings as well.

Final Setup

With the Drak built and the center-of-gravity set at 1.25" forward of the edge of the front spar, I set the reflex to the recommended angle shown in the below graphic, and dialed in 1/2" of elevon throw from center.

Flight Performance

From the first launch, I knew the Drak was going to be a great aircraft. I held the fuselage with my left hand in front of the leading edge, pointed it vertical, and pushed full throttle with my right hand. The Drak wants to fly right out of your hand with it's awesome power-to-weight ratio that's over 1:1. With the prop spinning, just throw the Drak up and out. It will leave your hand at about a 50-60 degree angle and instantly get on the wing with very little loss in altitude. Some pilots are terrified of this type of launch, but it's actually quite easy and safe; you would have to literally throw your hand forward after releasing the Drak to come anywhere near the spinning prop, and that's just not possible during the release as your hand naturally sweeps up and out of the way. Watch the video in this review to see how easy it is to launch.

In the air, the Drak handles very well, especially with a CG that's slightly forward. If you're experimenting with CG locations and begin to creep rearward, you'll notice how much more pitch sensitive the Drak becomes very quickly. Keep the CG forward and you'll be rewarded with a docile flying plane, even at higher airspeeds. Let's assume were flying in calm air and reading GPS ground speed from the Vector or similar GPS OSD. Cruise speeds are around 50-55 mph with an amp draw around 10-13 amps. You can drop the throttle a little more and pull around 8 amps for a low cruise speed in the mid 30's, but going any lower that that starts getting too close to the stall speed in the mid 20's. Wide open throttle gives a very respectable top speed of 85-90 mph, with an amp draw around 50 amps; launching the Drak is naturally where you see the highest amp draw around 70 amps.

Your control throws will dictate how agile the Drak is, and it's quite nimble with the recommended 1/2" up and down from center on the elevons. Roll rate is respectable for it's large wingspan, and can be dialed up if you desire. Some people put the elevons on dual rates for more authority when landing, although I kept my throws at 1/2" and had no problem with controlling the Drak as I slowed down to land. Landing usually east up a lot of real estate with big aerodynamic flying wings, but the Drak actually slows down in a slight nose-up alpha and creates a lot more drag than a conventional flying wing without a center fuselage. I was able to aim for a specific point and drop the aircraft down and come to a complete stop in usually less than 20 feet from my target.

The optional 5s 8000mAh Ritewing LiPo is a huge fuel tank for the Drak, giving mixed-throttle flight times anywhere from 15 to 20 minutes, assuming full throttle is used generously. Dialing back the throttle to a 10 amp cruise, and the Drak could fly for well over 30 minutes or more.

Final Thoughts

The Drak is a versatile FPV aircraft that builds quickly and flies superbly. With it's 90 mph top speed and 50+ mph cruise, the 60" Drak can satisfy the need of many FPV pilots looking for a step up from their Bixlers and Skyhunters. It's fast, nimble, yet quite docile in slow flight - an important aspect of any aircraft. One of my favorite features of the Drak is how easily it hand launches. With an above 1:1 thrust to weight ratio, the Drak literally wants to fly out of your hand.

Ritewing decided to use a new EPP foam with the Drak, and the results are a very smooth and strong aircraft that doesn't need to be wrapped in iron-on laminate like previous Ritewing Zephyr did, reducing build time considerably. I would highly recommend going with the Secret Sauce motor and esc offered by Ritewing, as the combo is a great fit for the Drak. There's also a number of accessories available if you want to customize your aircraft such as the nose protector, electronics bay floors, and pre-fabbed carbon fiber pushrods.

As always, thanks for reading my review of the Ritewing Drak, and happy flying!

Last edited by Matt Gunn; Aug 24, 2016 at 11:31 AM..
Thread Tools
Aug 23, 2016, 04:54 PM
Registered User
Shifteer's Avatar
Great review Matt. Chris Klick of Ritewing has designed a winner with this one! There's a dedicated community of fans of this aircraft on RCGroups and also a great Facebook group out there very willing to help out anyone wanting to try out this beast. The build is actually one of the easiest and most straightforward of any wing kit out there.

It flies really really well, just be sure to start out a little nose-heavy as many of us flipped it on our first launches. On the bright side, the tough foam handles unexpected contact with the ground very well. Also, with the stock 5S power kit it's fast. Really really fast! It actually made in-flight trimming a little bit of a challenge as it's nearly out of sight before you can get anything done. Finally, make sure you give it 100% throttle on launch as it needs the punch to get out properly.

I'd recommend the Drak for anyone bored with regular wings or bigger, slower FPV airframes. It handles a ton of battery but flies fast and like it's on rails. As Matt mentioned it's big and carries a lot of mass, so make sure you have enough space to land it.

Enjoy!
Aug 24, 2016, 12:05 AM
FPV Dealer,Getting People High
Johnnymeg's Avatar
Love my drak"s" besides flying amazing they are fun to build.
Aug 24, 2016, 01:03 AM
Registered User
I was late to the FPV party. The Drak was my first FPV build. The couple I've built since don't compare. I can't wait to buy the mini.
Aug 24, 2016, 07:29 AM
Registered User
Bill Glover's Avatar
Nice, but $350 for a bare foam airframe
Latest blog entry: Eachine QX65 FPV quad review
Aug 24, 2016, 08:14 AM
MK
MK
Registered User
I did notice the price also of just the bare frame.
Aug 24, 2016, 08:23 AM
www.gunnphotoservices.com
Matt Gunn's Avatar
Thread OP
Quote:
Originally Posted by Bill Glover
Nice, but $350 for a bare foam airframe
The price is relative to the end user. This is a considerable chunk of "bare foam". Its a high quality, dense EPP with time invested in development, which always plays into the price.
Latest blog entry: www.gunnphotoservices.com
Aug 24, 2016, 09:50 AM
Mum is the word!
There are over 50 pieces in the kit alone. The mold was made in Germany, the foam is a German foam. So if you want crazy quality and the most durable aircraft ever made it does cost a little more.
Its a performance aircraft with 9 lives and a super high crash per dollar rating.
Aug 24, 2016, 10:06 AM
Registered User
Bill Glover's Avatar
Quote:
Originally Posted by klique
There are over 50 pieces in the kit alone. The mold was made in Germany, the foam is a German foam. So if you want crazy quality and the most durable aircraft ever made it does cost a little more.
Its a performance aircraft with 9 lives and a super high crash per dollar rating.
Sure but compare with the price of a top-end Multiplex model though?
Latest blog entry: Eachine QX65 FPV quad review
Aug 24, 2016, 10:19 AM
Mum is the word!
Multiplex is EPO foam !
It is still not a good comparison.
Multiplex elepor foam is dead on one bad launch or landing.

I have yet to see a Drak that was not flyable or still repairable , even after being piledriven . Do this with your multiplex

The new Drak foam (6 min 5 sec)

Quote:
Originally Posted by Bill Glover
Sure but compare with the price of a top-end Multiplex model though?
Last edited by klique; Aug 24, 2016 at 11:27 PM.
Aug 24, 2016, 10:33 AM
www.gunnphotoservices.com
Matt Gunn's Avatar
Thread OP
Quote:
Originally Posted by Bill Glover
Sure but compare with the price of a top-end Multiplex model though?
Nothing wrong with the Multiplex planes, I like them and own a few. But what plane are you referring to? The Drak is a completely different aircraft than anything Multiplex offers except the Funjet in shape. However, the size is vastly different.
Latest blog entry: www.gunnphotoservices.com
Aug 24, 2016, 10:34 AM
You sabotaged my plane.
eliworm's Avatar
Both my son and I have Draks. Love the build and the way they fly. The thing that really impressed me with this aircraft is the way it breaks down to transport around.

Jim
Aug 24, 2016, 11:26 AM
Rádio Controlado
ricardovasc's Avatar
The installation of the horns are correct?
They are not aligned with the elevons line.
Aug 24, 2016, 01:05 PM
Mum is the word!
They work great where I put them , by design the servos are very close the vertical.
I do not want to have control rods crossing the airflow in this area where the flow is being compressed against the vertical wing fence. I would rather have them aligned with the flow, not crossing it.
I also do not put them in the wing center, this can cause flex issues.

The drak flys awesome, see vids



COFPV | Ritewing Drak First Flights (5 min 3 sec)


COFPV | Draking Jones Pass (4 min 28 sec)


ritewing Drak smooth (3 min 48 sec)


Quote:
Originally Posted by ricardovasc
The installation of the horns are correct?
They are not aligned with the elevons line.
Last edited by klique; Aug 24, 2016 at 01:10 PM.
Aug 24, 2016, 03:56 PM
Registered User
Bill Glover's Avatar
Quote:
Originally Posted by Matt Gunn
Nothing wrong with the Multiplex planes, I like them and own a few. But what plane are you referring to? The Drak is a completely different aircraft than anything Multiplex offers except the Funjet in shape. However, the size is vastly different.
Obviously a completely different type of plane but size-wise you could compare with the Multiplex Fun Cub XL - that's a bit bigger (67" span), and much more complex:

http://hitecrcd.com/products/airplan...ub-kit/product

Seems to retail at around $200 in the US.

Don't get me wrong - I think the Drak looks great. But I still think the price is pretty steep for what it is.
Latest blog entry: Eachine QX65 FPV quad review


Quick Reply
Message:

Thread Tools