Added new article on propellor loading and choices.

I just updated and uploaded an article on comparing and choosing propeller sizes.  It’s something I wrote long ago for a newsletter but hadn’t put up here on the web site yet.  Hope you will find it useful.  To access you can either use the Articles link or just click here to jump to that page.

Telemaster 40 – The workhorse of my fleet.

This is a picture of me with one of the oldest planes in my current fleet….  The Telemaster 40.


(I’ll add some basic stats here later….)

I built this airplane from a kit back around 2000 or 2001 and I recall telling folks it was a box of sticks with some loose suggestions about how to build an airplane!  It wasn’t all that bad, but it wasn’t like the newer kits that have pictures for every step either.  It was a rolled up set of plans with about 5 pages of double columns of fairly fine print for instructions.  The plans are well drawn and the instructions about as clear as you can get but there were still many challenges along the way.

In any case, the results are a very light, great flying machine.  Notice I didn’t necessarily say it was “easy flying” because I don’t think of the Telemaster as a great training machine.  I’ve instructed for a few years and I would pick any number of the newer trainers over the Telemaster as a first airplane.

Flying wise, I’d say the Telemaster is great, but somewhat different than most planes. Maybe closer to the way a scale cub flies than most trainers.  Getting the most out of this plane requires you to use rudder to avoid a lot of “skid” in the turns and the flying tail combined with the tail-dragger configuration forces the proper application of rudder and elevator to get smooth take offs and landings.

But don’t get the idea that this means it doesn’t fly well.  It’s a blast to fly since it weighs in at something like 5.5 lbs with a Saito .82 for power (probably one of the few trainers of this size that truly would fly well with a standard bushing .40!).  It floats down and lands so soft and easy that it’s hard to tell when it is actually on the ground.  Throw in the flaps and low passes can last what seems like minutes as the plane almost hovers while remaining parallel to the ground.  With the extra power of the Saito, takeoff rolls are optional with comments like “Gee, you almost rotated those wheels a full turn before you left the ground!” being common.  Of course you can feed the power in easy and do a nice “pick up the tail and roll sedately down the runway” type takeoff once you get the hang of it.  Touch and goes can be done similarly without the tail wheel ever making contact but the mains on the ground for 200′ or more… if that’s your preference!

Because of the sturdy and light construction, you can carry a drop box, strap on floats, maybe a camera, carry a glider aloft… whatever you like.  I’ve done all these and a few others just because I can.  Rolls can be slow to moderate… truly fast is not in the cards with the 6′ wingspan and small ailerons but you can add rudder to get a little quicker roll if needed.  Stall turns and inverted flight are no problem, in spite of the dihedral and loops are no issue at all.  The tail feathers are quite a way back there and the surfaces there are fairly large so rudder and elevator are both quite effective.

Assuming the ARFs are half as much fun, I would recommend a Telemaster to anyone interested in a versatile, fun to fly plane.  It’s a step up, skill wise from most trainers but it’s worth the effort and will teach you some really good lessons about using the wing, what that left stick is for besides going faster (if your mode 2) and allow you to get into all sorts of interesting related things like flying on skis, floats or whatever.

In case you were wondering, the “Wonder” color scheme is the second incarnation of this bird.  It’s earlier “Italian Green and Red” color pattern which was a bit more traditional looking had seen better days so winter of 2012 I made a change and stripped the covering down to it’s mostly white base.  I then recovered a few damaged areas and ended up with a basic white palette.  Having a set of dies handy to make circles of various sizes with little effort and a bunch of colors of leftover covering spawned the idea and the newly re-named “Wonder” plane was re-born!

Now all the best puns are heard often.  “I have a lot of bread tied up in this plane”, “It’s a wonderful flying plane”, “It’s a little slice of heaven”…   You can imagine.


GPS Telemetry – First Flight

I picked up the Spektrum GPS module over the Christmas holiday.  Somehow I was not even aware when this item came on the market but when I saw the ad for it I knew I had to try it.  I immediately dropped an email to my friendly local hobby shop and a few days later I picked it up.  I already have telemetry in my Wildhare 50cc size Slick as well as my Topflite P51 “Redtail” Mustang but this, in my mind, was a totally different level.  I’ve already posted on some basic telemetry usage in my Radian glider, but being able to track altitude, heading and speed in addition to GPS coordinates was potentially a game changer.  In my mind, there were so many possible upsides to this new sensor.

The module is a bit pricey, but you have to keep in mind that the GPS module is a possible replacement for a couple of the other existing Spektrum sensors and therefore some of the sting of the ~$100 price tag is diminished.  When you throw in the heading and position facilities the module starts to seem a bit more reasonable.  Lets be honest, none of us fly RC airplanes because its a particularly cheap hobby do we?

That was my train of thought when I got busy and installed a TM1000 and the GPS module in my trusty Telemaster 40.  Looking at the local weather forecast on the shop TV convinced me to add the floats as well.  Skis work in some snow conditions but I have found floats work well on a wide variety of ice/snow or water.  A quick test start on the trusty Saito 82 and a good overnight charge and all was ready.  A couple days and 4-6 or maybe it was 6-8 inches of white stuff later and January 1st, 2013 dawned calm and cool.  Time to test out the new GPS module!

After a nice long flight, I entered our club’s nicely heated shelter, downloaded the telemetry file and emailed it to my old (original model) Ipad.  As you can see by this clip (I’ll insert a video here eventually) the STI application can overlay the collected flight track on what appears to be a satellite shot of the flying field.  Then you can replay and watch as the entire previous flight plays out as a small airplane icon moves across the map and leaves behind a trail of arrows.  A window can be brought up showing all the GPS information as the flight plays out on the map.  By noting the heading, altitude, speed, etc… and comparing to the track you quickly start to recognize loops and stall turns and can easily see just how close you came to that tree line or how high you really flew.  This is extremely cool stuff with some real life usefulness behind it.  Here is a small sample video showing the first minute or so of my flight.

You can see a fair bit of information in this.  First its around 808ft above sea level at our field.  You’ll see it on the screen until about 24 seconds in when I take off.  You’ll also notice the time in UTC format.  Locally it’s a minute or so after 9AM which is when we were allowed to start flying the “noisy” planes at this event.  My speed ranges up to about 65mph (that is full throttle and a pretty steep dive) and my max altitude above the 808 foot base seems to be about 250 feet toward the end of the clip.  At about 1:23 you will see the speed drop to near zero and a very quick heading change as I perform a stall turn… at least the best I could with floats on a Telemaster!  It takes a bit to figure things like that out.  You just have to imagine what is happening that would cause the changes in altitude, airspeed and heading to reason it through in most cases.
Of course there is plenty of room for improvement.  Here’s my top three:
  • Allow me to pause the flight and clear all those little arrow tracks.  After a while I can’t see the airplane icon for all the little arrows.
  • Give me the ability to “zero” the altitude with the push of a button and let the program do the math to tell me what the variance in altitude is from that point on.
  • Put a scale of some sort on the screen so I can get some sort of idea of relative distance… even better if I could set a zero point just as I’d like to do with altitude and let me see distance from that point.

Having said that, this technology makes a lot of valuable information available to us.  During part of my flight I flew out “close” to our northern tree line… or so I thought.  On review I had more available space than I thought.  Very good to know.  When practicing for IMAC, one of the prominent issues to watch for is flying a straight line parallel to the runway with a constant altitude.  Without the ability to do this you will never score well at a contest.  This is a lot more difficult than you might believe.  With GPS telemetry, you can answer these question once and for all.  As you might guess, the GPS module has already been moved (likely permanently) into my Slick (my IMAC dabbling plane) and another has been ordered.

How fast?  How far?  How high? Where?  When?  All those questions are answered once and for all with GPS.  I can’t wait to get a plane in the air with a GPS combined with a “full boat” of other sensors.  Ever wonder how your engine temperature varies with throttle and speed?  What the unloaded RPMs really are in flight?  I’m looking forward to learning all those things during this upcoming flying season.

I’ll try to write up an article some time soon showing all the Spektrum Telemetry pieces and parts and the ins and outs of making the system work.  There are some small quirks but nothing overly difficult and the information gained is fascinating.