F5J Contesting at SVSS - RC Groups
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Dec 31, 2014, 09:12 PM
Team Hello Kitty
SoaringDude's Avatar
Discussion

F5J Contesting at SVSS


Since mid year I have been following the well-developed F5J contesting action in Europe and as I learned I became more and more intrigued with the format. So when I finally asked Aric in November whether there were any 2015 plans for F5J, and his answer was "not yet," it seemed the perfect time to start up a dialogue on how we might go about introducing F5J to our club.

After discussions with club members as well as other California pilots who share the same level of excitement for F5J, it really did feel like the time was right to kickstart this format at SVSS. If we do the right things SVSS could provide a similar catalyst for F5J contesting in the US as it did for ALES just a few short years ago.

I look forward to adding more posts soon and sharing what I've learned about F5J. No doubt you'll ask good questions that will help guide us in integrating F5J into our contest flow. As a member of the club's F5J events team I look forward to listening and responding to your feedback.

Chris B.

P.S. And yes I'm working on getting an electric Xplorer going
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Dec 31, 2014, 09:16 PM
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F5J versus ALES: A Quick Overview


F5J is similar to ALES as an electric man-on-man thermal duration format but with several key differences in launching, penalties, and scoring. The main difference is that in F5J you are rewarded points (actually, fewer penalty points) the lower you fly during the launch phase. Landings are still important but with this single change it is less the case that contests turn into just "landing contests" when thermal conditions are good; instead, the pilots that win F5J events are the ones that can demonstrate superior thermaling skills by hooking lower altitude thermals during the launch phase and still complete the round. This difference can turn F5J contests into very exciting "thermal battles" in later rounds. So F5J can be a great spectator sport. Bring plenty of popcorn!

General history note: The roots to F5J and ALES go back to about the same time: 2008-09 for pre-FAI F5J and 2010 for early ALES contests . Formal FAI regs for F5J were first published for the 2011 season so F5J has a solid 4 years of FAI-defined activity, especially so throughout Europe.

In an upcoming pair of posts I'll offer a deeper dive into the differences between AMA/SVSS ALES and FAI F5J.
Last edited by SoaringDude; Jan 01, 2015 at 01:13 AM. Reason: History additions
Jan 01, 2015, 02:08 PM
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F5J Contest Video


Curious what an F5J contest is like? This is a great demonstration of an F5J round where everyone took a shot at staying very low for maximum points. Start viewing at 5:35 for the launch and low altitude gaggle where 3 planes finally made it up with lots of good thermaling while 2 failed after giving their best. This is what F5J is all about.

F5J German Open 2013 in Weilheim

It is recommended that you view this in full-screen mode using at least 480p resolution, even better at 720p. This will give you the best plane details.

F5J German Open 2013, Weilheim (26 min 9 sec)


For more favorite F5J vids, go here.
Jan 01, 2015, 02:18 PM
Good for what ALES you
awilmunder's Avatar
Happy New Years Everybody!

As Chris mentioned, discussions about F5J go back quite some time, and for those that have flown ALES, many aspects will be quite familiar. Equipment wise, the key difference is that in ALES, everyone launches together to a preset altitude and a ‘limiter’ cuts off each motor. F5J uses a slightly more sophisticated device called an Altitude Motor Run Timer, or AMRT. The AMRT records the plane's altitude a few seconds after the motor is cut off, and your launch altitude is used when scoring your flight. This allows the pilot to decide whether to launch to a higher altitude and receive fewer points, or to risk a lower launch and trust in their ability to catch a thermal. You can even continue to use your ALES limiter, and simply report the preset altitude cut-off plus a small zoom factor.

Chris has been looking into different AMRT devices, and there may be some exciting news to share.
Jan 01, 2015, 03:12 PM
E sailplane thermal hack
Can the AMRT devices also be configured for ALES as well???
Being able to pick ones launch height DEFINATELY adds ALOT of interesting strategy choices.
Also without the impetus to reach 200m in 30secs means one can use a smaller less expensive power system.
Last edited by Airman74; Jan 01, 2015 at 03:27 PM.
Jan 01, 2015, 03:27 PM
Team Hello Kitty
SoaringDude's Avatar
Hey Jerry,

Quick answer = yes. For example, the Aerobtec Altis v4 device works for both F5J and ALES. If you look at Figure 10 in the user guide on page 11 you will see the "Competition" tab in the config program. If you click both the "Altitude switch" and "Time switch" boxes it becomes an ALES limiter. Cool eh?

Chris
Jan 01, 2015, 04:30 PM
Good for what ALES you
awilmunder's Avatar
Along with the CAM limiters I use for ALES, I also have a Sky Limit that I used at the SAM Champs in 2013 for an ALOT (Altitude Limited Old Timer) event. The Sky Limit can be set to different launch heights and different durations before motor cutoff. It is no longer being sold but it can be used for both ALES and informal F5J events.

I believe that for serious F5J events, the AMRT can't allow you to adjust the launch time, and they may restrict the ability to restart the motor. I'll look into this. The FAI rules are a bit of a challenge to parse.

When ALES was introduced, there were lots of discussions about zooming, and the F5J rules address this by recording the altitude at 10 seconds AFTER the motor is cut off, presumably after any zoom would have taken place.
Jan 01, 2015, 04:39 PM
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SoaringDude's Avatar
Quote:
Originally Posted by awilmunder
I believe that for serious F5J events, the AMRT can't allow you to adjust the launch time
Correct. In fact, with the Altis device for rigid FAI contests (e.g. regionals) you have to download and install F5J-only firmware. But for our club events the "standard" firmware will nicely handle both.

Quote:
...the F5J rules address this by recording the altitude at 10 seconds AFTER the motor is cut off...
Not quite. An F5J AMRT records the peak altitude between motor start and 10 seconds after motor cutoff. That becomes your F5J Start Height.
Jan 01, 2015, 04:48 PM
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Rules? We don't need no stinkin' rules!


I suppose no F5J thread would be complete without the official rules being posted somewhere. As Aric suggests they're kinda "twisty and turny" in places but overall not too bad.
Jan 02, 2015, 01:22 PM
E sailplane thermal hack
I've been playing around with my sky limit in f5j mode,, it's kinda cool being able to select your cutoff altitude . Some things I've noticed,, it seems very hard ( at least for me ) to guess at what altitude I'm cutting off at. One flight my altimeter indicated a 141m cutoff and I made 18 min
On another I cutoff at 190m and only got a 6min flight. It's also nice knowing EXACTLY when your going to cut the motor so that you can avoid a stall at cutoff .
This is going to be very very interesting.
Jan 02, 2015, 01:57 PM
E sailplane thermal hack
I can see where this will make for some interesting strategy decisions. For example : I've noticed that my average sink times in minimal lift conditions average between 20-26m/ min
,,,,,, so let's say one competitor I'm flying against decides to cutoff at 150m,, but I elect to cutoff at say 220m,,, my point deduction would be 85pts compared to his,,, but if conditions are minimal with little lift,, my extra 70m might net me an additional 2 or more minutes ,, and since my negative 85pts would only offset 85secs ,, I could possibly still out score him because of my much longer flight time,, especially when you factor in the fact that lift generally gets stronger and covers a bigger area up higher. Plus the 15min fly off rounds should be REAL interesting.
Last edited by Airman74; Jan 02, 2015 at 02:29 PM. Reason: Poor math ;-)
Jan 02, 2015, 02:07 PM
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SoaringDude's Avatar
Quote:
Originally Posted by Airman74
I can see where this will make for some interesting strategy decisions. ,,, so let's say one competitor I'm flying against decides to cutoff at 150m,, but I elect to cutoff at say 220m,,, my point deduction would be 28pts compared to his,,,
I agree, with F5J all of a sudden there are more strategy decisions to make. One correction on your penalty calcs, though: at 220m your Start Height penalty is (200*0.5)+(20*3) = 160 points compared to the other pilot at (150*0.5) = 75 points. i.e. crossing that 200m line is v-e-r-y costly in terms of penalty points.
Jan 02, 2015, 02:34 PM
E sailplane thermal hack
Yes!! See my correction above,, my bad,, 85pt difference,, but,, that 85pts only offsets a 1:25sec flight difference ,,if my flight is 2:00 min longer at the increased launch height ,, I might still out score him..,, very interesting.

Ps edit : also,, if I chose to cutoff at say 200m in above example then the point spread between us is only equal to 25sec .
Jan 03, 2015, 02:24 PM
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nodlehs's Avatar
Remember...Where you choose your cutoff, and when the devices sample the altitude are 2 different points in time, and hence possibly altitude. Cutoff occurs at the altitude programmed, THEN, the altitude is sampled 10 secs later and that is the "launch altitude of record", as I understand it (and I could be wrong). If you don't want to go over the costly 200M line, you should actually set your limiter so that the cutoff is lower and stay just under that 200M penalty line and ensure that you are under that 200M "ceiling".

Sheldon
Jan 03, 2015, 03:00 PM
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SoaringDude's Avatar
Hi Sheldon,

Actually in F5J there is no "cutoff" there is only a 30 second motor run time limit. So you can climb as high as you feel is necessary to make your round time.

The AMRT device (e.g. Altis v4) continuously samples your altitude and records the peak it sees between motor start and 10 seconds after the point where you cut the motor. That peak is then the Start Height used to calculate your launch penalty points.