Bixler 1.1 V2 Kit-Build and mod ideas

Build or buy?

Having just finished the kit  I can say with all certainty that if you haven't built many planes as of yet you should probably buy the PNF (Plug and Fly) version that comes with all the major electrical components installed.  You just need to plug in a radio and you're set.  The  Kit/ ARF (Almost Ready to Fly) version comes without good instructions on how to build it.   The ones you can download online from HobbyKing 's website are for the PNF and not for the kit (ARF).  Which is a fancy way of saying, if you take on the kit, you're kinda on your own.

The PNF comes with a 1900KV motor which is plenty strong enough for flight. It balances right with a 2200mAh 3S battery.  The plane will fly well and you'll enjoy it.   And yet, this doesn't appeal to me.

Why build the kit?

Your first mid-fuselage pusher is your throw-away plane.   I still have my original SkySurfer V8 but it's been so mistreated that if it could it would be writing country music songs about me how I've abused her.   If it wasn't for this plane I wouldn't have fallen in love with the mid-fuselage pusher concept.  But, I also learned how to build them.

Metal gear servos-  There are four servos on this plane, two are difficult to get to in the body of the plane and the two on the wings see more than their fair share of abuse.   The  PNF comes with PLASTIC servos (yuck).  If you have plastic servos they are fine until they break and then you get to pull them out if you can and put in metal gear servos.  That's why I avoid the PNF

Motor options- There are some compelling motor options for this plane, even if you don't go the route of installing the optional upgraded motor mount.  At the time I bought this Bixler, Hobby King only stocked the upgraded motor mounts in Hong Kong.  The kit showed up right away, and it sat there until the motor mount showed up a couple of weeks later.   For the money, it's worth the wait.  If you can't wait there are aftermarket ones sold on eBay here in the states which I've used and they do work well.



When you go this route you are building a plane that is at least 700g in weight. The flying weight on my plane is 908g.   So, let's review for a moment, weight on a plane, good or bad thing?  I say it has to do with the type of plane you've got.  If you overload a flying wing, it still flies but it can do strange pitches and rolls and that usually isn't easy to correct.   You may find that the plane will fly a bit better in a good breeze than on breezeless days but it may never be just right.  The Bixler style planes have a lot of wingspan and they can take on the extra weight a bit better.   And yes they do fly better with a bit of wind.   Since the shape is like a glider you can refer to Alan Moore's video on how to add ballast for gliders.  You'll be surprised how much weight you'll need for a rip-roaring  windy day on the slopes.  The point is, the Bixler can withstand a bit of weight and you may find it actually flies better.

The downside of weight is that you'll need thrust to get the plane off the ground. This means having a motor that is within the thrust-envelope of the weight of the plane. If you're motor can only put out 600g of thrust and your Bixler weighs 900g then even if you could get the plane flying it will struggle the entire time.

What to look out for in the kit build


Servo placement

In the fuselage

There are two things you have to look out for.  The first is that the TowerPro MG90 9g metal gear servo didn't fit into the holes cut out for servos.  It required an Xacto knife to gouge the hole a bit deeper.  If you don't don this, the servo arms may rub against the top of the fuselage.  This could restrict the movement of the servos.  Since this is your elevator and rudder we're talking about, you don't want this to happen.



The other issue which to me is a major design flaw of the plane is the potential for the arms of these two servos to touch.  I had this happen with a Radian.  There's nothing like watching a Radian nosediving to the ground.  How I resolved this issue was to cut the servo arms even shorter so that they could never touch.  Did I lose a bit of control?  Maybe.  Have I noticed it at all?  Nope.

On the wing
The servos that go into wing for ailerons have restricted travel on the side closes to the leading edge. This was one again fixed with a little gouging with an Xacto knife.  It's a minor mod but worth mentioning.


Before you glue the fuselage together

There is a large wooden piece that has a fairly good sized hole in it and places for two screws.  This holds you wing together in case you want to screw them in.   I don't know what it is about the Bixler line but they seem to have the worst ideas for attaching the wings.  The problem with screwing in metal screws is that if you have a bad crash the screw cut through the foam.  Surprisingly enough, the pieces fit together nicely with the rods and the simple compression fitting.  If worse comes to worse and I have to look for a more permanent solution I would rather glue the wings on.  If you go this route look into plastic screws to replace the metal ones.  They break during a crash.


Motor lead extension
If you have extra wire, bullet connectors , heat shrink you're better off making this piece yourself.  In retrospect I made mine a little short. It worked, but barely.  If you're going to use the upgraded motor mount you'll need even more wire.  I suggest making it 12" (30cm) long.  After you hit the "Buy" button on Hobby King's website is a good time to make these three wires.  It's probably a good time to get all the electronics in order.

Extra Homework while you're waiting for your plane to arrive.

In that downtime between ordering your plane and figuring out what you're going to tell your wife there are a few settings you should learn on your radio.

Rudder-Aileron Mixing

There isn't a great video that explains this, and I guess for each transmitter it's different.  If you're a fantastic pilot you know how to bank with your rudder and ailerons.    But, there are ways to have your radio do this for you.  Since each radio is different you're going to have to research how to do this.  The end result is very worth it.  You want your rudder to point to move to the side where the aileron is up.  For extra credit, I changed the differential on the ailerons. The side that goes up goes up 100% of the way. The side that goes down only goes down 70% of the way.  The helps in fighting off adverse yaw.  It sounds nice, right?  The turns on the plane are so much smoother and doing this has added to my enjoyment of the Bixler.

Camber

This function droops the ailerons down and acts like flaps when you're launching. Make sure both go down significantly.  Put this function on a switch and once the plane is flying, turn off the camber.

The motor/prop combination I selected

The Bixler had dihedral on the wings.  The means the go up on the ends. What this does is to help level the plane.  It's about as effective as a good set of gyros.  The downside is that it effects performance.  Everybody has their own style, I like slow and quiet.  I also like  using motors that I have laying around.  I had a BR2212 1000KV motor laying around and thought it would be a nice touch to this plane.   The motor matched with the thrust needed to power this plane.  I put on a whopping 9070  triple bladed propeller.  My flights are lasting over 25 minutes and this platform is perfect for adding cameras.

Right out of the gate the plane flew great.  I need to fine tune the CG. It could probably stand another 14g in the nose.

Fine tuning the launch sequence

Put the plane on between 40 to 50 percent power.  If you can launch from a small hill all the better. The plane enjoys a bit of wind to launch.  My perfect launch combination is a well-balanced plane,  starting on a hill that is up about 3 feet high, and holding the plane close to the nose with my left hand and doing a five-step jog and toss.  Mid-fuselage pushers aren't easy to launch and thus would be horrible planes to suggest for beginners.

The landing

I have some planes that are so nose heavy that they have to be landed with power  If there's no power I have to point the nose down toward the ground so that it picks up enough speed to not stall  and then pull out of the dive about 20 feet from the ground and hope for the best.   Not my idea of fun.

The Bixlers land without power like they have the best gyro stabilizers you can ever imagine landing them.  It just puts a smile on your face when it lands.

Bixler 1.1 V2 or the Bixler 2?

They are very similar planes and chances are you don't need both.  They are so similar, I suggest buy what appeals to you.  There is only 10cm difference beween the planes. I will say that I find the build quality and engineering on the Bixler 1.1 V2 to be a tad bit better.  But, the extra 10cm makes for a smoother flying plane on the Bixler 2.  So, it's really a tossup.

Andrew Newton explains the PNF very nicely. If you're building the kit get ready to hit freeze frame a few tims to help you figure out what to do with all those extra parts.












Forget what you think you know about gliders.  Allen Moore talks about ballast and wind. This reinforces my point that a little extra weight won't hurt a Bixler.

Andrew Newton takes on rudder mixing with aileron.  He explains how to add it on a knob on a Taranis.  This is well worth learning and can really add to the enjoyement of your Bixler.  Mine is on all the time. I don't find that I ever need to turn it off.

Small Parts CNC makes a motor mount for the Bixler which is around $15 US. This guy takes about 10 minutes to explain 2 minutes worth of information.  I have this mount on my Bixler 2 and it works well.  I like the products from Small Parts CNC.