Monday, October 14, 2013


Because FanKar(t)
(Version 1.0)

For several years I've been fooling around with fan propelled R/C vehicles - FanKar happens to be the latest incarnation. Stemming from June 2012, FanKar has gone through plenty of modifications and several hilariously terrible accidents.

Probably half the people who frequent RC events have seen or driven some form of FanKar. In the beginning it was a "let's see how fast we can make a fan on wheels go." type of thing, but it turned out much more awesome than I expected, and probably a few others too. 

Fankar is fantastic, there are many reasons why. I'll attempt to list a few in the hopes that some of you may understand what it means to FanKar.

1. It's got a power to weight ratio almost exactly equal to a 2013 Formula 1 car.

2. It's got almost no suspension
3. There is almost no engineering forethought into FanKar.
4. The steering system is made almost entirely of plywood with a few brass tubes as bushings.
5. FanKar has been clocked at 87mph (right before it exploded).
6. There are no brakes.

7. The wheels are held on by zip ties
8. There is almost no protection for any of the components
9. The steering servo is nearly too small, and has no servo screw.
10. The steering system is under-defined.

These are a few of the reasons why FanKar is like that cheap abused plane that should've died many flights ago, but you just keep flying it because you love it, and probably don't care if it explodes (which would just add to the hilarity).

Shown above is version 1.0, or the first version that you could drive in a remotely straight line above half throttle. One of the largest issues with these air propulsion RC vehicles is the thrust line compared to the Center of gravity.

Generally with onroad racing cars you want to have the Center of gravity as low as possible to promote quick directional changes - this is true with fankar, it also helps it stay on the ground when you accidentally sideways (which happens a lot). Low CG is a problem when you introduce a thrust source of some kind because generally it will be above the CG.

this creates a moment arm, making the rear wheels "light" with power input....that's not generally great for stability, so I decided the easiest way to fix this was to add a blown rear wing element.

Stealing pages from the F1 Pagebook, I added this piece of foam behind the fan to create rear traction with thrust.
It worked extremely well, the drivability increased to a level it had not been at before; read (you could go to full power in a straight line and keep it there) You could even make slight left and right turns at full power. Wow, exciting! of course now I saw this as an aero project and started to go crazy with CAD. I turned out a few crazy CAD designs which all utilized the blown rear wing technique. Then I decided that I would ruin the "FanKar-ness" of FanKar if I got too technical about it and added a simple top element and endplates/vertical stabilizers. Also present are new black fiberglass rods to control chassis flex torsionally:

This is the part of the story when FanKar's true potential was realized. I dropped about 10 MPH top speed, but the car had incredible grip and was very stable...until it wasn't. It drove how I thought a fan propelled vehicle should drive. The only problem with this configuration was that the foam actually wasn't strong enough to cope with the high velocity airflow provided by the fan over the double element rear wing...I figured this out when all of a sudden the wing departed in similar fashion to this Kimi Raikkonen accident:

(Pretty much the same thing happens to FanKar when the wing comes off)

here's an after picture of the wing with damage from tumbling after separating from the car.
(also present is a thru-fan receiver.)

At this point I got tired of fixing the foam rear wing and decided to build a stronger and more durable setup.

Enter alternative building materials.

The structure was now comprised of 1/16" plywood endplates with carbon tubes supporting the elements on the underside. You can see the lower tube is also attached to a link which connects the wing to the chassis in a way that I can break the glue joint from the lower wing element to the chassis and adjust the angle if I found that it was needed. This wing worked really well, I actually picked up speed and rear downforce over the Depron version, meaning it was a more efficienct setup. It also didn't fail just driving around, which was a plus.

And now for the tragic end to FanKar 1.0 in the form showed above.
I was showing some friends how awesome the latest FanKar was and forgot how to drive it-
coming off of the throttle means you lose all of your rear downforce with this setup. It behaved like the Raikkonen crash above and swapped ends.....right into a parking block at near top speed.
The car had taken off as soon as it went backwards and landed directly on a parking block without bleeding off much speed at all. It broke nearly everything important.

Components that survived:
the wheels minus a few flat spots from the snap turn, the main chassis rails and rear axle, the fan (I don't  know how) and the ESC. Everything else was broken enough that I didn't really want to deal with it and set the project aside. 
Here's another picture of the car after the crash:

The Fankar chassis still lives in the FanKar box and someday I'll get around the implementing a few more ideas once I become interesting in air propulsion vehicles again (which could be soon, because it's almost that time of the year again)

Anyhow, here's another form that the FanKar chassis has seen since it came into being:

it's a ceiling car...and it sucked, literally.

It worked pretty well until the suction battery voltage would trigger the low voltage cutoff in the ESC,....then you better run and hit throttle hold 'cuz it was coming off the ceiling.

now onto an abbreviated CAD portion of this post -
I'll leave a few of these here for thought.

(above) This was designed for a 70mm fan around a set of rules a few buddies and I had come up with.
(below) Rendered here is a 120mm all out racecar designed around the Formula Fan series rules, maybe it will spur some interest and we can see some truly innovative RC car racing?
time will tell, I'll leave you here with these below.



yup, I did it, I ran out of funds. (start the finger pointing)

actually, I didn't run out of funds building the airplane, or even designing the airplane for that matter - I ran out of funds because some other important things needed to be taken care of. Unfortunately that means the end of the SR-1 racer for this year, however,  it might see a comeback next year in the growing sportsman class.

(end finger pointing. Don't you feel silly.)

The event is scheduled to begin on the 24th of this month (October) and conclude on the 27th. I'll be on site from Friday the 25th until Sunday the 27th, and I'll make sure to take plenty of pictures and do a brief write-up when I return home - hopefully I can grab a few videos and throw them up on Youtube or something.

In other news,
I've already begun preparing for the 2014 AMA Expo. I'll be there flying in the demo area for entertainment and demonstration purposes, come drop by if you'd like! Also, feel free to ask anyone in the demo area about their aircraft or anything else we might have on hand, it's our jobs to promote and explain our great hobby to anyone and everyone in the hopes that we can help people, or even bring new people into the sport.

Quite possibly a week or so before the event I'll compile a list of projects/planes/devices I'll be bringing as a primer for the event.

Skyfighter Updates:

I've been working on perfecting Skyfighters for about 3 years now and I'm really happy with how far they've come. For once I'm nearly satisfied with how something flies and I see no reason to change my 2013 AMA Expo build for this upcoming year, if you'd like to know more about my equipment choice and a few details regarding the model, you can check out the link to an earlier blog post > Here <

I'll do a build log on the 2014 airplane when it comes time to fully prepare for the 2014 Expo.

In the meantime, I've done something a bit silly with a heavily used skyfighter: 

Look, it's a mini-fighter!

This is what a Skyfighter looks like if you cut about 3" out of the center section, add about 5 degrees of sweep,  and splice in a couple new leading edge and nose pieces (the same could be achieved by just cutting part of the wing root out).

Motor: Hacker A05-13S
Servos: Hitec HS-35HD
Battery: Aero-Model 240mAh 2s 30C LiPo
Receiver: Spektrum AR6310 DSMX
Transmitter: Spektrum DX18

The DX18 is currently available as a bonus buy package from Horizon Hobby Currently at this link: 

of course there's been more Skyfighter shenanigans.

I'm not even sure this one needs an explanation.

Notice the two pieces cut off the front of the wing. Remember how I said I "borrowed" some nose pieces for the planes above? well there you go, these are the panels I borrowed them from.

The airplane itself is fairly small. The wingspan is about 18", with the center section consisting of an Estes 24mm ID wrapped cardboard tube made for model rocketry....and I'm using it for such a purpose - the rear of the tube holds a D-sized rocket engine (also Estes)

The plane flies with this equipment:
ESC (used as a regulator) : Hacker X-5 Pro
Servos: E-flite DS60
Battery: Aero-Model 240mAh 2s 30C Lipo
Receiver: Spektrum AR6310 DSMX
Transmitter: Spektrum DX18
Rocket motor: Estes D sized
Igniton Controller: E-flite 10-Amp Micro Brushed ESC

Overall it's a very fun plane to fly. We've only glide tested it so far (dropped from another plane). Soon enough we'll throw in a live engine and light it off...(I figure we should wait and fly it at a legitimate club where rockets are approved in order to keep everyone happy)

Last but not least (for this blog post anyway) is the Thunderbird.
Pictured here after a successful flight.

I built this thing originally about 2 years ago and only flew it once because it requires two people to actually get it into the air and I was having trouble finding people interested in piloting a rocket vehicle.
speaking of which - It's air dropped from a Multiplex FunCub pictured here with the Thunderbird sitting on top in the launch rig:

and a behind shot for good measure:

The plane flies really well and is incredibly stable. It has a fairly low CG, and a high wing mounting position with a slight amount of anhedral for maneuverability purposes and to cup the air a little bit at high angles of attack. The Thunderbird relies on tailerons to maintain control. Tailerons describes a configuration where you use what would normally be the 'elevator' surfaces for roll control as well as pitch control. In the radio (DX18), I have the airplane set up as a delta, enabling delta mixing. It's extremely tame and it self rights, infact we have not been able to get it to roll past 90 degrees yet, it reaches about 70 degrees and just stops rolling. It's certainly interesting and I believe it's due to the low point of control, and high positive roll stability which overcomes the force from the tailerons. Furthermore, I think adverse yaw has a play in it as well, but probably not as much as the other two factors.

A few construction details:
The wing is carved, then finish sanded from three layers of 6mm Depron bonded together with spray adhesive. The airfoil is a 

NACA 2412. Finally it is covered in Orange flavored Japanese tissue paper using 3m Super 77n as the adhesive, then shrunk slightly with  a water mist.
The tail is built from two layers. One layer is 1/8" thick Balsa wood with a fair amount of cross grain, it is the top layer and of course, visible from the top. The bottom layer is 1/16" thick Balsa, it consists of a heavier density wood with large amounts of cross grain with excellent structural properties, it's glued on with Elmers wood glue at a 45 degree angle to the top layer to promote torsional rigidity which is needed due to the rectangular vertical fin shape....and flutter prevention in general. The vertical stabilizers are made in a similar fashion with two layers of wood with the grain structure 45 degrees off of parallel. I then added carved Balsa wood fillets to increase the bond area and provide better load carrying torsionally from the vertical stabilizers to the Horizontal stabilizers. 

the fuselage is constructed primarily of 6mm Depron with 1/4" Balsa wood glued to the corners of the box structure to add longitudinal rigidity as well as ding resistance (foam dings easily, especially sharp corners....) There are several Depron structures inside to hold the wing/engine tube and the forward electronics bay, which is accessible from a door on the underside of the model.

The radio equipment consists of:
ESC (being used as a regulator again): Hacker X-5 Pro
Servos: E-flite DS60
Battery: Aero-model 450mAh 2s 30C LiPo
Rocket motor: Custom ArcherAero 29mm Diameter
Ignition Controller: E-flite 10-Amp Micro Brushed ESC

This concludes tonight's updates, check back soon as I continue to write about my current projects and some cool stuff we have going on soon.



Wednesday, August 7, 2013


New this year to USRA racing is the "Sportsman" racing class. The Sportsman class was brought forward to introduce new people to the sport of air racing in a cost effective and convenient manner. the baseline rules for the Sportsman class are pretty simple.
*12lbs dry weight
*80" or greater wingspan
*Propeller driven aircraft only
*Must be based on a full scale aircraft design that was designed and flown in the year 1930 or later
*Design must be proved scale within 5% of the outline of the full size aircraft
*Times of less than 120 seconds will result in an immediate disqualification
*No form of timing is allowed
*Deviating for the purpose of slowing will result in a warning - Two warnings will result in a disqualification

The Sportsman class is a breakout class, meaning,  If you complete the allotted number of laps in less than 120 seconds you're immediately disqualified. This is where the Sportsman class differentiates from every other class of USRA racing. It allows people to experience the thrill of air racing with an airplane they may already own.

A good example would be a person with a 100cc aerobatic aircraft who is a competent pilot, but lacks funds to put together a purpose built racing airplane.

>Enter the Sportsman class<

The pilot in question now has a perfectly eligible aircraft to race with! Whoaaaa, the magic of the Sportsman class is revealed!

I suppose this is the part where I tell you my plans for the upcoming race.

oh, right....the race.

The championship ending event will take place October 24th-27th at Rabbit dry lake bed in 
Lucerne Valley, California.

This year I decided it would be fun to enter the Sportsman class since I don't have an Unlimited at the moment...of course me being myself, I spread the word as much as I possibly could about the class and my plans to enter hoping to drum up some interest within my friends and their friends.
In typical crazy RC guy fashion plenty of people are interested, and I'm pretty sure we'll have a team of 3-5 guys flying some fairly unique aircraft.

I have 11 weeks to complete this project. I'm currently devising a plan to design and build the airplane(s) on time, and on budget in order to make sure we can test fly before the event to ensure everything's going to work properly and in a safe manner.

It's been difficult to chose just one airplane design to build for this task...I mean, there have been more than a few airplanes design and flown since the 1930's....however, I've finally made up my mind.
Sticking with the racing theme, I've chosen the:

SR-1 "SNOSHOO" (above) 
The SR-1 is a Formula 1 class aircraft built with modern construction techniques and materials. People who would like to know more about this aircraft can visit their website (where you can also purchase plans to build your own full size SR-1!):

The Sportsman edition SR-1 will differ in a few ways from standard USRA aircraft construction.

The idea is to develop an airplane that is cheap to make, quick to build, and very competitive within the sportsman class.

I plan to do this with a construction largely of foam and the addition of clean and smooth electric power.
Generally these types of planes are powered by a piston or rotary internal combustion engine (ICE), however, that would mean I'd have to fuel proof the airplane if I were to carry out my first plan of using foam as the main building material. Another issue would be vibration. Vibration is a killer even with the current breed of hollow molded carbon fiber aircraft. It would mean having to overbuild the airplane so much it would become heavy and non-competitive. 

Currently I'm in Phase 1 of the project which is: Equipment Selection & Airframe Design
I'm  currently planning a timeline, then I'll jump into equipment selection which will determine the structure of the airplane.

The equipment used will all be standard, so after this is all done I can release the plans, files, and an equipment list so everyone can build one if they want to!

The Sportsman SR-1 will be a 5 channel airplane.
It'll have:
(2) Aileron Servos
(1) Elevator Servo
(1) Rudder Servos
                   (1) Electronic Speed Controller

The servos themselves don't need to be anything too spectacular, I'll report back with what I decide to use after I make more progress in Phase 1.

anyhow, I'll leave you with a few more pictures of the SR-1:


Saturday, August 3, 2013

Where in the world is Ryan Archer...and what has he been up to? (part 1)

July was a busy month full of traveling, flying, and vacationing. (vacationing can be busy, right?)

My July adventures started off with a trip to Cupertino, California to help my good friend Todd Bridges (another crazy RC airplane pilot) finish up a neat little RC plane that he has been working on for several months. The plane itself is a 2.3m (91") wingspan all composite scale model of an Extra 330SC made by Composite-Arf. The airplane arrives from Thailand at your doorstep in a large wooden box with fabrication of the main parts done. You, the builder, are required to install and rig the necessary inner structures and equipment to make the aircraft flyable. That doesn't sound too hard, right? It's normally not a big deal and one can build this type of an airplane in a week without too much trouble. However, being crazy rc airplane guys, Todd and I had talked about using a Desert Aircraft DA120 engine in the plane, purely to make it *more exciting*....and to avoid adding dead weight to the nose of the plane to make it balance.....

The recommended engine for a CARF 2.3m airplane is a DA60.
Specs for DA60:
*60.5cc Displacement
*around 7Hp at 7200RPM

aaaand here's the DA120.
Specs for the DA120:
*121cc Displacement
*14Hp at 7000RPM

So.....maybe a bit overboard...nahhhh it'll be fine.

So a few months passed after we had jokingly discussed it on the phone and little did I know Todd was serious.
"You don't think I'll do it...I'll do it!" - Todd Bridges

one day I received a picture of a perfectly shortened engine dome from Todd. This is when I knew he was srs bdns.

Over the next month or so I received a steady flow of progress pictures until finally the airplane was nearly ready to fly, only a few things were left to do and we were both getting excited....until the airplane had to be shelved for a month do to important things that  needed to be taken care of first.

fast forward to Tuesday, July 13th when I arrived at San Jose Intl Airport with a suitcase full of airplane stuff.
(side note: people look kind of concerned when you pull your RC transmitter out at the airport security checkpoint...I've never actually been questioned while going through security at an airport.)

Todd was there to pick me up and we quickly went back to his house to start on the plane.
The goal was to get it finished by Wednesday morning in order to go test fly it later that day, however that didn't end up happening. We had a few setbacks, namely the engine didn't actually fit inside the cowling.... so Todd had to (painfully) cut some holes in the sides for the spark plug caps to pass through. The rudder servo was moved from inside the airplane near the fuel tank tray to the rear of the fuselage so it could be hooked directly to the rudder with a Push-Pull linkage. I prefer to use this type of linkage when I can, I think it's much more solid feeling in the air than a Pull-Pull setup with identical servos. 
(as long as the geometry is correct)
Todd had backed up the cutout with good quality 1/8" plywood to stiffen the rear of the fuselage as well as providing a good material to drive screws into in order to hold the servo in place.
Next we made a carbon tube X-brace to support the canopy opening, which is usually where planes of this type fail. Todd used 10mm diameter tubing with a 0.5mm wall thickness, we then inserted balsa wood dowels into the tubes so they could be drilled through and screwed to the underside of the canopy frame as well as epoxied in place.

(I actually forgot to take pictures of the work we did because we were in such a hurry to finish)

I then started playing with the elevator/stab assemblies because I thought the Phenolic/Steel wire pin hinge was sub-optimal. There was more slop than I wanted between the phenolic horns and the steel hinge pin.
The solution is to drill out the phenolic horns and insert bushings. Seems simple enough...until you realize modern hobbyshops don't seem to carry much metric tubing..if any at all. :( We ended up driving to three different shops until we finally arrived at a vintage style shop, which had of all things, many control line models, slot cars and all sorts of vintage RC abnormalities and memorabilia which you don't normally see in what has come to be the standard hobbyshop of the 2000's.

This particular shop carried a full line of brass and aluminum tubing in Metric and Imperial sizes.
 (however they happened to be out of brass tubing we needed unfortunately)
We decided Aluminum tubing would do for now, and purchased a pack.

Installing the tubing was easy and it improved the slop a great deal, enough to where I was very happy with the control surface operation. I decided to bush the rudder as well just to make sure it would continue to work correctly over the event weekend.

Currently it was Wednesday evening and we decided to delay flight testing until the next day in Santa Maria where we were meeting up with a few other competitors for pre-contest practice. This meant Todd and I had time to go meet up with some Friends,
Jordan and Joe, who happen to work in the area and are both MIT graduates and very interesting might check them out!
Jordan's blog:
Joe's blog:

Anyhow, Todd and I finished up the plane that evening and got ready for our two leg trip to the Camarillo IMAC contest. We got up on Thursday morning, packed the trailer and headed off to Santa Maria where we had a semi-successful test day involving 4 flights on Todd's main precision plane, but none on the extreme 2.3m. We had issues with the battery tray operation, so Cameron and his father (other competitors) were gracious to let us use their shop to fix the 2.3m, as well as treating us to an excellent dinner at a secret steak house! (fun fact, lots of high level engineers and rocket scientists frequent this place)

Fast forward to the event

Friday morning we headed off to the event location, The Camarillo Condors model field. The field had been shut down for over a year prior to the contest due to a large fire which spread through the park burning most everything except the model field, it was the only structure/area not burned within sight. The field is located on university owned land, which means they control when we can and cannot fly. They felt it was for the best interest of the park that we shouldn't fly there in order to not hinder the growth of new plant life. They were gracious enough to grant us permission to run the contest albeit with a large amount of restrictions, but hey...I can understand their concern, and we're grateful they even let us fly there in the first place.

The contest went off without a hitch. There was a high level of participation in all the IMAC classed, plus freestyle. There weren't any crashes or any damaged aircraft, it was very professionally run and I'd definitely come to any contest run by Joe and Uncle Frank.

I didn't fly in the contest, I was mainly there to help Todd and his father in any way I could, as well as helping with the event if need be. I ended up flying a few planes and landing for a few people when the weather conditions became slightly adverse, I still had a great time though. Sometimes it's good to just go and help if you can...people in the hobby seem to genuinely appreciate it.

Cameron ended up winning both Unlimited and Freestyle with very high scores. I'd like to congratulate he and his father, as well as thank them again for letting us use their shop to work on the 2.3m.

after the event had been wrapped up and the trophies given out we were able to leave the field Sunday afternoon around 4Pm, which put us back in Cupertino around 11Pm, all in all a very fun trip, and I'm glad glad I went. 10/10 would do it again.

this concludes part 1,
check back for part 2 at a later date.
Part 2: The never ending layover + San Diego adventures.

Friday, April 26, 2013



You may be wondering what the heck that thing is?
 It's got 4 cylindrical things near the extents, and is sitting on a flat surface.
Therefore it must be a spaceship, AM I RIGHT?!

okay, just kidding. It's a teaser render of what I'm calling a TeslaRacer.
As the name suggests, the car(s) will use electro/magnetism to generate the correct amount of grip for a realistic racing experience.

The idea for this project was implanted in my head while I was watching the Bahrain Formula 1 race on TV a week ago. 
(If you're into formula 1 and you haven't seen the race, I highly recommend you find it online or on TV somewhere. It was a very exciting and entertaining race from start to finish and I really enjoyed it.)
As I was watching the race I was trying to compare RC car racing to it's full size counterpart...I ended up coming up with this conclusion.

 RC cars are very fast for their scale.
1:10 scale RC touring cars routinely reach speeds of 60mph or more on a large track. That means if they were full size cars, they would be traveling at a blistering 600 miles per hour.

1:10 Scale
Most of these RC cars are raced on a track that is quite a bit smaller than 1:10 scale of an actual race track at which their full-scale counterparts would compete at. Granted, the lane widths are exaggerated to compensate and make it possible to keep the car on the track without hitting everything every time.
Even with the generously wide track it's still quite hard to keep the car on all 4's while managing a good lap time...throw in 9 other cars and now you have to deal with passing or being passed. Everything happens really, really quickly. In fact, too quickly for most average drivers to react. Even the pro level drivers run into each other almost every time trying to pass or block...sometimes on purpose, sometimes because it happens too quickly to react.

Smaller Scales
The problem with current small scale RC cars is very similar to my statement above, the speed is far too much for a normal human to react quickly enough to control the car in a realistic manner, even more so when overtaking or being overtaken, therefore the tracks have been adjusted to make it possible for racing to take place, but really all that you're doing is passing the other yellow blur that just so happened to miss the apex by 16 inches, when you only missed it by 8 inches.
Which brings me to my solution:
The end goal of TESLA-RACING is to provide an in home hyper-realistic racing experience for minimal cost and without the need for superhuman reflexes, while maintaining a minimal footprint so that a realistic track may be permanently set up in a spare room or a shed.

TESLA-RACING is unique because it allows the driver to race on a track which is scale width, nearly scale speed, with realistic handling and grip levels. In other words, full-size car racing knowledge applies when driving a TeslaRacer. In order to complete a fast lap you must understand the limits of the car                   and the limits of the track.
 Ex: how fast you can travel around certain corners, the correct entry and exit line, and the braking points etc. All of this will transfer over to TESLA-RACING.

The Track:
Enter the MagnaTrack.
(MagaTrack Prototype-1 racing surface/pit lane layout without scenery or detailing.)

Wait,.... MAGNA...track?, MAGNA? ...Are there magnets in the track as well as the cars?
Why yes, yes there are.
That's the one of the main advantages of the TESLA-RACING system.

There are in fact electro-magnets embedded in the racing surface. This allows the builder to define a realistic racing line as well as have the ability to simulate many different track or weather conditions.
The cars generate a small amount of mechanical grip all by themselves (how cute), but this is where the beauty of the system lies. 

Everything is tune-able!
Speaking about the track tune-ability, say you've decided to simulate a rain race. You would go about this by turning the track magnetism level to a very low setting, but not entirely off since you still want to simulate a  racing line, which is accurate to full size racing. A 'dry line' appears from cars displacing water as they travel about the circuit, so it's reasonable to have a small amount of grip on the racing line, that's not to say you can go full out like you could in dry conditions.

TeslaCars, 1:32 scale.
I've based these first prototype on 1:32 scale dimensions. The concept can be applied to any scale, but this size seemed most do-able from the manufacturing point, as well as keeping the size of a decent sized track compact enough that you don't need to buy a warehouse to enjoy it.

Another good reason to base the cars off of 1:32 scale is that there is a wide range of realistic 1:32 scale  slot cars of which to steal the bodies from. You can purchase pretty much any car you'd like in 1:32 scale. It seems as though almost everything has been made at some point or another and all you have to do it look around. I've been watching Ebay and purchasing models of full size cars from racing series' that I'm interested in,  hoping that I would be able to make use of them some day...this seems like the perfect application.

The handling is tune-able.
The handling of a car can be tuned rather easily.
There are 6 separate magnets located on the underside of the chassis.
 There is a magnet placed at each corner of the furthest extending part of the chassis located near the front and rear wheels. These magnets are the largest magnets used on the car,                                                  and they set the overall grip level of the car. 
For instance,
 a Formula One car should not have the same amount of grip as a Toyota Prius hybrid.(sorry Toyota). Therefore, the Formula One car will have much larger magnets than the Prius, increasing the grip level.
Handling can also be tuned by magnet size and placement.
 there are 2 further magnets to complete the 6 magnet set. Both located underneath the car,
 one at the rear and one at the front.
 These are small magnets, basically to control how much each end of the car is allowed to slide, and which end slides first.
 For instance, if you have a rear engine sports car it will most likely me more tail happy for the same tire width/size, similar wheel base/track width, and similar power levels. So, to simulate this correctly, you'd need a larger/stronger front magnet, and a smaller/weaker rear magnet. It's all a balancing game, you can completely change the handling characteristics of a car just by the amount of magnets, the size,
 and the placement.

With these first prototypes I will be using conventional RC equipment which limits the choice of car subject to be simulated due to space and layout inside the bodies.
 Eventually I'd like to develop a standalone unit based off of a single PCB with a tailored form factor that's more conducive to fitting underneath some of the more spatially challenged subjects.

(TeslaCar Prototype-1, a simple design for evaluation purposes.)

I'm currently at the point where I'm ready to start making things, and I'll post an update as soon as I make some progress towards the end goal. Hopefully some of you are as excited as I am about this project, and it can eventually end up being a thing people can buy/make themselves, and in home realistic RC racing can be had by all!


Sunday, March 10, 2013


No really, It's true.
Here, this is why:

So much fun.

Earlier this year Hacker Brushless released the A05 motor. It's a motor that's nearly half the weight of the powerhouse A10s motor (7.5 grams vs 14.5 grams), but quite a bit more power per gram (35w/55w). For applications where weight and power is of utmost importance, the A05 is the motor for you.

On the Skyfighter in the video I was running a Hacker A05-13s motor at about 40 watts on a GWS 4530 propeller (4.5" diameter, 3.0" pitch) and an Aero-Model Silver Series 30C 2s 240Mah LiPo. It seems rather happy at 40 watts and only gets mildly warm, about 5-10 degrees F above ambient. I think you could push the motor a bit harder if you had a reason to, but for this application 40w was more than enough.

Whoa, there it is!

D'awww, look how cute it is :D

My current Skyfighter is decked out with this equipment:

Motor: Hacker A05-13s
Propeller: GWS 4530
Electronic Speed control: Hacker X-5Pro
Battery: Aero-Model 30c Silver Series 7.4v 2 Cell 240Mah LiPo
Servos: (2) JR DS188's
Receiver: Spektrum AR6310 DSMX

I'm flying the Skyfighter (and most of my other planes) on a Spektrum DX18 Radio
click here -> DX18! <- for the DX18 page on Horizon Hobby.

Here we see a few nicely built A10s Skyfighters.

Oh, right, the colors.
They come in all sorts of colors:




The Team Edition! (oooohhhh)


So, if you'd like to try a Skyfighter for yourself, feel free to pick one up from the good people at   Aero-Model.

The main Aero-model site is -> Aero-Model
The Skyfighters are located at the bottom of this page -> SKYFIGHTERS!
The motor is located at this link -> A05-13L
Ryan, what about the ESC? It's right here -> X-5Pro
You'll want some good batteries too. 
I recommend this one for my setup -> Silver Series (30C) 7.4v (2s) 240 LiPo
At this link you can find some servos ->  Hitec HS-45HB Servos

In a future post I'll detail the steps I go through to make a Skyfighter just a little bit better. 
until then, hopefully some of you decide to try a Skyfighter! They're really a fantastic flying little plane that you can take just about anywhere. They're also very durable, and even if you manage to break one, a little Medium CA and you'll be back flying in no time.


Saturday, March 9, 2013


My name is Ryan Archer, and I am a professional R/C pilot.

Now you may say, someone can be a professional R/C pilot?

My reply would be "Yes." It's my main job and I travel all around the world flying model aircraft in competitions and demonstrations for cash and prizes.

Here, have a look at my 2012 Tucson Aerobatic shootout freestyle flight:

The competition is structured as such. 
You're scored in a handful of categories,
1. Precision, How well each maneuver is executed
2. Wide variety of maneuvers showing slow/fast flight and control in each area
3. Choreography, how well the flying style fits the music
4. Presentation, how well the maneuvers flown are displayed in the sky using the entire flight box
5. Technical Merit, How difficult the flight or maneuvers were in the flight displayed

Each category has a multiplier (K-factor). The raw scores are then tallied, then round winner's score is normalized to a perfect 1000 and everyone else's score then normalized to that 1000.
That gives the placing for each of the three rounds. You're allowed one throw-away round out of the 3, which means all caution is usually thrown to the wind in the third round and some quite spectacular things happen.

Take this for example.
In 2011, Fellow pilot David Moser was only 20 points away from knocking me out of third place so he  did as I said above and went all out, crashing his plane in the process, which gives him a big fat zero for that round, enabling me to lock up 3rd place without having to fly the last flight (but I did anyways).
Oh, right, The video.
Start it at 1:10 if you want to skip straight to the crash, it's quite spectacular.

After the crash we all run out to help pick up the parts, as you hear the commentator (Bob Sadler) say, we were all high-fiving on the way out because even though it's terrible to crash it's always exciting. No matter who you are you can always appreciate a good crash..... also, I'm fairly certain at least 20% of people only come to see a good crash anyways ;)

Whoa, I got distracted...(get used to it)...back to the Shootout story.
In 2012, after 5 days of grueling competition I ended up second in Freestyle.
 Here's a picture of me involuntarily taking a champagne bath.

and a bath it was. I was thoroughly soaked.

Big checks?
Of course, everyone likes big checks:

Here are some photos of my three Freestyle flights:
(click them and they'll enlarge)
(Resist saying "that's what she said.")

 In close proximity with the ground performing "Rolling Harriers"

 A "Knife Edge Spin" with smoke on
 Dad and I running checks and starting the plane for round #2
 A full throttle downline maneuver just after the start of the flight.
 This one here's a down line snap, once again at full power with smoke on
 Pulling out just above the trees from a 45 degree down line 
Rolling half loop at full power, You can see how great the forces at play are on the fully composite airframe.
 This was a slower part after a vertical tumble
 Starting to bring it in low and slow for an "Inverted Harrier"
 A nice high alpha knife edge pass with smoke
 The bottom side of a rolling loop with smoke
 Just after streamer release from the tips
 Second shot showing a clean streamer release
 This was at the bottom side of a "Blender" which is a full throttle rolling down line into an immediate flat spin, a very violent combination of maneuvers. 

 A knife edge pass towards the photography section
 Pulling up away from the crowd with smoke on
A successful crosswind landing in 40MPH winds after  successful round 2 flight.
 Game face still active.
This was one of my favorite parts of the 1st round flight, a full power inverted pass only a foot and a half above the ground.

Competing against 20 of the worlds best R/C Aerobatic pilots requires serious commitment and dedication. I practiced for 3 solid months, 8 flights a day, every day.
It becomes your life, everything else around you just stops and all you can about is that next flight.

You show up for the competition a week or two early, get used to the surroundings, assemble the planes and check the equipment. Make sure nothing has been damaged in transport, set up the mobile pits and team camp, check in with everyone and then after all that is satisfied and if the weather is decent enough for test flights, you wait in line for 6-8 hours for a test flight. With 70 other pilots also trying to make sure they're ready it can get pretty hectic. You've just got to play your own game, and keep a clear mind, The first person you have to beat is yourself.

The field turns into a miniature town, filled with people from many countries camping out and sharing stories and goods from other lands. Last year we had competitors from 13 different countries, including judges there were 15 countries total. It really is the biggest event of its kind, for our sport of Giant scale R/C aerobatics.

There is over $100,000.00 worth of cash and prizes waiting to be distributed to the winners, but you can't have that in your head either or you'll make a silly mistake, and missing a snap roll by 5 degrees can cost you the whole contest.

Think about that, 5 degrees. how much is 5 degrees? In IMAC terms it's one-half of a point. When you only start off with 10 points per maneuver you can't afford to leave anything on the table, especially at an event like this.

We can also think of it in Deg/s
the aircraft I fly in Precision competition is capable of a 600Deg/s roll rate,
now how small is 5 degrees? Very small.
5 degrees takes about 0.009seconds

That's a very small, or rather short window that's very easy to miss.

Every little bit counts and I've already started preparing for the 2013 Tucson Shootout. I won in 2006, 2007, 2008, and 2009. Then, a year was skipped because of reasons unknown (probably economy, it's very expensive to put on an even of this caliber). In 2011&2012 I've been plagued with mistakes and equipment troubles leading to poor finishes in the precision portion of the event, which is completely separate from the Freestyle portion (by the way).
However, I seem to have either taken my frustration out on the freestyle plane, or somehow put it together in my mind and just went for it.

I didn't fly a single freestyle practice flight in 2011 or 2012, yet I managed to somehow make the podium both years, coming in 3rd in 2011, and 2nd last year, 2012.
Either I was lucky, good, or Just taking my anger from the precision side out on the cute little freestyle plane (poor little plane) possibly a combination of all three.

Anyways, That's my Tucson shootout experience in a nut shell, I'll post some specs on the planes I fly in the next few days or so,

have a nice little render of a small rocket glider flying over a nice mountain in some sketchy weather.