F5J 2013 Summary

We have just completed the 5th and final round of the F5J competition meetings.

I know that most pilots enjoyed the events and will probably be back for more in 2014. As the competitions were very informal I'm not going to concentrate on who won or lost, rather I would like to focus on the fun side of the events. To take the last event on Saturday 26 October as an example, we started the event at 09:00 and we all done by 12:00. To be fair, the windy conditions made it difficult to achieve full 10 min working time flights all the time. Add an hour for good flying conditions. We were still in time to have a braai and watch the rugby at home. Clearing the field took no longer than 10 minutes. No clumsy lines, winches, turnaround stakes or car batteries to lug around.

Some of the other disciplines I have attended, like F3B or F3K, places a lot of stress on an average pilot like myself. I am constantly amazed at the level of skill and expertise of the South Africans. For such a small model flying community we fare extremely well at most of the gliding world championships.

The point I'm getting at is that F5J, because of its provisional status, is very attractive to new and less skilled glider pilots. This may change as soon as it gains proper FAI status. At the moment it does not attract the crème de la crème of the local glider pilots as the other disciplines do.

F5J in Europe has a huge following, and I think for much the same reason. The Model Club of Trnava (MCT), in Slovakia has taken the initiative and have organized the F5J Inter Tour competition. It describes the procedures for allowing countries to stage and or enter the competition. More on the subject at their web site: http://www.trnavaf3j.sk/.

To make a long story short, I believe F5J to be the future of competitive model thermal duration flying. We are right here at the beginning of it all. Next year (2014) we should have more informal "practice" days and tighten up on the competition days.

If this recipe works well in Gauteng, I see no reason for other regions not to jump on the bandwagon. It would be wonderful to see a multitude of new faces at the 2014 Nationals.

Altis V4 - Now in stock

A new batch of the Altis V4 altitude loggers have just arrived.
Gone is the need for a separate display unit as the Altis V4 has an OLED screen to display information. The memory and other functionality has also been improved. The USB to Serial device is now on-board the device and the supplied cable connects straight to your PC. Go to Aerob Tec website for more specs and information.
Herewith a picture for size comparison with the Altis V3.

A bunch of these devices have been sold already, but I still have some in stock. Contact me if you need one.

F5J Scoring Application

There is a small app available to help you score individual flights. This will give you the points scored for each flight. There is no database to the app so you will have to log all your scores on a spreadsheet if you want to keep track of your progress.
This might also come in handy for producing scores for electric Postal competition.
Download the file here. Unzip the file and run. Remember that in F5J the scores are normalized.

F5J Scoring Flowchart

View here.

Competition Announcement

We're getting close to our next F5J competition. This one will be held at BERG (Bartlett Egg Radio Gliders) on Saturday 27 April. Flying will start around 09:00.
The field is located approximately 5km northwest of the M47 / N14 crossing near Krugersdorp.


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The remaining dates for this year are:

• 27 April
• 30 June
• 25 August
• 26 October

 Hope to see you all there!

F5J Round 1 Results

Thanks to all who made this another great event. 

Weather was warm and sunny and the wind favored the slightly heavier, molded gliders. We all had some good flying but the top guys seemed to have it all together. The race for top spot was between Gert and Johan with Johan taking the lead by a few points. Evan did well to finish in third against the big ships flying a Tsotsi. Well done guys!

My biggest hassle was hitting the landing spot, and I was not alone.

Many, many thanks to the girls that helped with timing and scoring chores.

Overall Score

Rank	Name	Score	Pcnt
1	Bruwer, Johan	4982.2	100
2	Nieuwoudt, Gert	4941.7	99.19
3	Shaw, Evan	4642.3	93.18
4	Brown, Gordon	3998.5	80.26
5	Williams, Ivan	3940.4	79.09
6	Jubber, Garin	3767.4	75.62
7	Wucherpfennig, Rouen	3614.5	72.55
8	Edmunds, Hugh	3356.9	67.38
9	Meyer, Melgard	2934.5	58.9

Thermal activity was quite good as can be seen from the tight formation the picture below:

We had a good mix of gliders from modified Gentle Ladies, a Radian, a few Tsotsis right up to Explorer-E and a Pike. Johan's Pike launches vertically (well almost).

Wingman Gert:

Merke, gereed.......

Hugh and Gert really concentrating.

Discussing tactics?

If this looks like fun please join us for the next event 27 April 2013.

Frequent Questions

• Why F5J?
• What equipment do I need in my glider?
• How does the points scoring work?
• Is flight time measured by the altitude limiting device?
• Does the motor run time need to be logged?
• What is the F5J altitude?
• How long are the flights?
• How much power do I need?
• What does the altitude limiting device do?
• How many motor runs are allowed?
• Can one adjust the cut off altitude to below 200m on the Altis?

Why F5J?

If you are tired of carting around a heavy and expensive electric winch, or you cannot persuade your two tow-men to come fly with you, then you are ready for F5J.

What equipment do I need in my glider?

1. A suitable electric motor, brushed or brush-less, in-runner or out-runner.
2. A folding prop to minimize drag once the motor shuts down.
3. An electronic speed control (ESC) for the motor.
4. An altitude limiting device.

How does the points scoring work?

The points system work by penalty for altitude. You get penalized 0.5 points per meter from ground level up to 200m after which you get penalized 3 points per meter.
For example:

• You launch to 160m (160 x 0.5 = 80 points)
• You launch to 225m (200 x 0.5 = 100 + (25 x 3) = 175 points)

This means simply STAY AWAY FROM 200m because it will cost you dearly. If the conditions are favourable you launch low (like F3J). In poor conditions, launch to 199m if you can!

Is flight time measured by the altitude limiting device?

No, it is measured by stopwatch. From when the plane leaves your hand, to the time it touches the ground or any other grounded object.

Does the motor run time need to be logged?

Motor run time is not logged, you get one motor run of maximum of 30 seconds, use it or lose it. The more powerful gliders will use maybe 10 or 15 seconds to reach altitude, but it gives them no real advantage.

What is the F5J altitude?

To prevent zooming to a higher altitude using stored speed or kinetic energy, the F5J altitude is the maximum altitude attained from the time of launch, until 10 seconds after the motor is cut. In other words, if you have a hot-liner and cut the motor at 150m it might be possible to still reach 200m due to the high speed (kinetic energy). The altimeter will then record not the 150m where you cut the motor, but the higher altitude attained by coasting along. It might be possible to launch into a good thermal and attain over 200m, thus penalty points, but in reality you are still in control, as you can cut the motor early or fly level. The power to weight needs to be optimized to get to 200m within 30sec...so outright power ending up with a weight penalty is not optimal.

How long are the flights?

Working time is 10 minutes (600 seconds). In F5J it is possible to fly the full 10 min. Time starts as the glider leaves your hand, and stops when you land. Fly-off rounds are 15 minutes.

How much power do I need?

I fly a Tsotsi (2m wingspan weighing about 1100g) with a Park 480 (brushless) and it has more than enough grunt to get up to 200m in about 25 seconds. Some pilots have rocket like fully moulded carbon gliders that gets them there in about 10 seconds. (these rigs can be quite heavy). I work by trial and error (I know that is not very scientific) but 300 or 350watt should get a 1500g glider up there in the allotted time.

What does the altitude limiting device do?

The altimeter device has 2 functions for strict F5J competition.

1. It limits the maximum motor run time to 30 seconds.
2. It measures the highest attained altitude within a 10 second period after the motor is shut down either automatically (after 30 seconds) or manually by the pilot.

Some of the limiting devices have many functions for example:

1. Records altitude, temp, throttle position, battery voltage etc.
2. Allows motor emergency on for practice purposes.
3. Allows setting the motor cut-off altitude.
4. Allows changing the motor cut-off time.

How many motor runs are allowed?

One only, for launch. The Altis will prevent you from doing a second run. The Altis has a "motor emergency on" feature that allows you to run the motor again and save the glider, but it is not allowed in strict F5J competition. Any additional motor run scores you zero for the flight.

Can one adjust the cut off altitude to below 200m on the Altis?

Yes you can: Again for strict F5J comp, this will not allowed, although it has not been written into the rules yet. In such a case you would have to judge your launch altitude

Event Announcement.

Ladies and Gents!

This is an early announcement for the first round F5J comp to be held at GEMS on Saturday 23 February 2013

Entries are open and a cutoff date will be announced closer to the time.

Please supply Name, Freqency and SAMAA membership number. Entries can be emailed to:

  

We will have pilots briefing at 08:30 to commence flying at no later than 09:00.

Provided we have enough entries we will fly 6 rounds with 2 slots per round with one throwaway.

Rules will be provisional F5J (with motor off altitude setting allowed!) The basics are as follows:

1. Max 30 second motor run time.
2. F5J altitude logging will be necessary for scoring.
3. Time measured from hand launch till landing or end of working time.
4. No landing score if working time is exceeded.
5. No flight (Zero score) if working time is exceeded by 60 seconds.
6. No flight (Zero score) if landin further than 75 meters from landing spot.

Please read the full rules before the comp although a copy will be available at the field.

Rules are available from here.

Pack a lunch as this will be a self catering event.

See you there!