SEN 2163

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Table of Contents – SEN 2163

  1. The Junior FAI World Champs in Prilep, Macedonia — Report  No. 1 by Bob Stalick
  2. USA Team Selection Reminder
  3. Early DT

The Junior FAI World Champs in Prilep, Macedonia — Report  No. 1 by Bob Stalick
The USA Junior Team has finally arrived in Macedonia and is ready for World Championship competition. I have been appointed as the NFFS Press representative for the event, and I’ll submit regular reports on the flying exploits of our team.

First, a short primer on Macedonia. Macedonia is one of the countries that was part of Yugoslavia prior to its breaking up. It is the southernmost country, landlocked and bounded on the North by Serbia, on the East by Bulgaria, on the South by Greece and on the West by Albania. It has a population of about 2 million, and has its own currency, as it is not part of the EU. It is also the ancestral home for Alexander the Great, whose statues and memorials abound.The capitol is Skopje (pronounced scopee). Skopje is the location of the International Airport, and is about 90 miles North of Prilep, the town closest to the contest site. Prilep, is a town of about 60,000. It is about 2000 ft in elevation, and the road from Skopje to Prilep here goes through a high mountain pass of over 6500 feet.
The field is located about 10 kilometers from Prilep, and it is of generous size. I estimate it to be in excess of a mile in length East to West and about 3/4 mile or so from North to South. In the 2 days that I have been on the field, the winds have been variable and generally under 5 mph. One our first two days here, the temps on the field have reached highs in the mid-80’s. The field has a few obstacles in the form of some trees on the perimeter, but it’s flat and covered with short, dry grass. Some crops are here and there, but they are not dense. The primary crops near the field tend to be corn, peppers, and tobacco. A small tended herd of cattle was seen on one edge of the field, and it’s apparent by the evidence on the field, that the cattle graze on it when it’s not being used for free flight competition. In all, it’s a good field, and it’s used for a number of different European FAI freeflight meets.

The competition field this year has 22 teams including the USA. Not all teams have a full complement of contestants in each of the three event, but the USA was able to fill all its slots..
I’d near like to introduce our team members.

Cade Fedor hails from Texas and is flying F1A (Glider) and F1P (Power). Cade’s grandpa, Mike, is along to help.

Troy Davis is from the Bay Area of California and he is flying F1b (Wakefield Rubber). Troy’s dad, Mike is along as his helper.

Sevak Malkhasyan hails from Southern California and is flying F1B (Wakefield Rubber) and F1PP (Power). Sevak’s dad. Gevorg, is along to assist.

Jace Pivonka hails from the Denver area and is flying (F1B (Wakefield Rubber). Jace is assisted by Chuck Etherington and is getting moral support from his mom, Andrea.

Alex Stalick is flying F1A (Glider) and F1P (Power). He hails from Southern California and is assisted by his dad, Ted, and now and then from his grandpa, Bob. Alex is the third generation of Stalick freeflighters.

Joel Yori is the last team member and he hails from  Maryland. Joel is flying F1A (glider). He is assisted by his mom, Aimee Sifleet and his grandpa, Bob Sifleet.

The whole team is organized and ably managed by Jim Parker.
That’s  it for now. More to come and pictures, too!

If you are interested in the updated scores, you can follow along on the official contest site <

USA Team Selection Reminder

Reminder for those USA Sportsmen and Sportswomen interested in participating in the 2017 US FAI Free Flight Outdoor Team Finals, October 5-9, 2016, your entry fees must be paid to AMA 25 days prior to the first day of competition.

Therefore AMA must have your finals entry fees received by Monday, September 12, 2016 (the 25 days actually falls on a Sunday).  If you are using the buy in method for advancing to the Finals your fees will be due at that time as well.

You may contact Colleen Pierce at AMA to make payment.   Charlie Jones Chairman of the T

Early D/T
In a recent SEN Aram reported that his F1Q model D/Td early in an event.  He speculated that this was caused by irregular power or some electromagnetic interference… I have got a number of questions since then.  Here are some reasons and answers, these may not apply all to Aram’s case

Firstly the timer, battery, servos and Radio D/T must be installed and programed properly.  The timer must have not been subjected to some form of physical or electrical abuse.  The battery should have been fully charged before the start of the current flying session and you need to understand how many flights you can do before needing to recharge the battery.

Servo: As a servo gets old and starts to fail or one of the wires deteriorate the servo can move to one end of the travel. The solution is to replace the servo.  Note that you can detect this on models with more than one servo because one servo would go to the end of travel that might D/T the model but other servos would be working OK.

Momentary Power Failure:  Some Radio DT units send the timer a DT signal on start up.  In normal operation, this is not a problem, because the timer is not ‘looking’ for the DT signal at that point so ignores it. However it appears that the timer is more resilient to power fluctuations than some RDT units.  That means if the voltage sags for some reason the RDT will be affected first. In this case the Timer will keep running but the RDT unit will reset and as part of it’s startup will send a DT signal that will DT the model.  Typical reasons why the voltage may sag  include a heavy battery drain because of heavy servo load during the launch sequence of an F1A model.  In Aram’s it appears that the BEC (Battery Eliminator Circuit) function of his ESC (motor controller) did not deliver clean power to the timer. This is fairly unusual.  This momentary heavy load can also upset servos for example causing a digital servo to “reboot” or any servo to jitter.  This form of power failure may also occur if the RDT in nor plugged in properly or the cable connecting the timer and RDT unit is worn or defective so the RDT unit become loose and make an intermittent connection

An additional device plugged into the timer can upset the power supply:  If an additional 3rd party device is plugged into the timer power it may either impose a heavy load or transmit RF energy down the power lines. Typical items would be tracker transmitters or flasher units.  Firstly if you do this make sure the battery is big enough to handle the additional load.  The heavy load could have the momentary power effect as mentioned above.  RF energy down the power wires can upset circuitry in the timer or cause serious servo jitter. Note that servo makers test their servos in environments with R/C frequencies but flashers and trackers can generate energy on different frequencies.   For example never plug that new flasher into your timer battery for the first time in the fly off for an important event without having tested it for a long test flight in similar conditions.

Failure to do preventive maintenance:  We said at the beginning that the equipment must be installed properly.  Being successful in competition free flight is about being well prepared and not messing up. Part of that is to check you equipment on a regular basis to make sure that everything still mounted properly, no connections are coming undone and that batteries are still charging up and maintaining their charge.

Note that all the major makers of RDT units include a proprietary digital security code so it is very unlikely that someone would be able to D/T someone else.  Similarly because this digital code is required it very unlikely some electrical or RF energy incident such as an electrical storm, R/C aircraft or drones or some other transmission of the ISM (Industrial, Scientific and Medical) band that is used by most RDT units.  It is also possible for the Timer or RDT unit to fail, this too is possible but unless the electronics have been damaged very unlikely compared with the other possibilities

Roger Morrell

Magic Timers

Roger Morrell