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PostPosted: 04 Jan 2008 01:38 am 
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Dear fellow F3F pilots,

The first race of HK F3F league for the year 2008 will be held on 13 Jan 2008. In order to avoid any confusions and arguments later on, we need to define some house rules for the league. We have discussed possible rules and logistic arrangements based on last year experience and suggestions by fellow pilots via email communications, but I think we need to post them out here to let all other pilots interested in F3F in Hong Kong to know about them and to invite for further comments before we fix them on HKRCSS web site as official record.

The following rules are what I have summarized. Correct me if I am wrong or missed out something. Further comments and improvements are welcome. Please check on the link

http://www.hkrcss.org/F3FGroup/HKF3F_league_rules.html

Here I would like to highlight a few points:

Incompleted race in 1.3 is up to our discussion, it is only my thinking, please give comments.

I proposed to assign a contest administration team to set up the race course and manage the contest. If you all agreed, we need to work out the assignments now.
May I invite proposal for fellow pilots on who would like to be in the team for January first?


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PostPosted: 04 Jan 2008 09:44 am 

Joined: 02 Aug 2004 11:34 am
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I've some suggestions:
For 1.2 - Should wind diection exceeding 45 degree to the direction of the race track be also a critical factor to call for abortion or cancellation of the round?

For 4.3 - I think the pilot can ask for abortion if wind condition drops rapidly after launching. If the CD permits, he/she can re-fly. If CD does not permit, the pilot can give up the round at his/her decision and land the plane; no re-fly be allowed. Thus, immediate decision has to be issued from the CD. It'll be disputable after the pilot landed the plane and trace for the request on abortion.

For 4.4 - Contest fee has to be fixed for that year. Revision can be made for the following year upon review by committee.

Other concern - When there are foreign/guest pilots joining one or a few races in the league, will their results be counted to qualify for attending international races?


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PostPosted: 04 Jan 2008 12:52 pm 
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On the point 4.3 Re-fly, the helpers must be told not to affect the pilots at anytime during the race. My past experience is whenever the wind speed dropped, the helpers talked very loud immed asking for re-fly, the pilot was affected by that, some of them even turned their head backward to look at the CD and helpers. This make the CD have no choice but to let the pilot re-fly.

It is difficult to predict the wind strength in next second. I suggect pilot can wait a certain time to launch their plane, but once the plane launched, he should finish the 10 legs even if the wind speed dropped. Re-fly or not will be decided by CD after the plane landed.

Some pilots will keep waiting for good wind to come before they launch their plane, this will affect the schedule. If CD feel that the wind should be good enough but the pilot still wait, he can warn the pilot to launch their plane immed or dis-qualify him.

If CD feel that the crash Launch due to the bad launch skill, he can let the pilot fly again and the pilot can also use another plane to fly if the plane was damaged. But they can only use thir own planes, this should be the rule.


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PostPosted: 04 Jan 2008 02:24 pm 
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I have modified the rules according to Allan's comments (highlighted with yellow color) for 4.3, 4.4 and other concerns.
http://www.hkrcss.org/F3FGroup/HKF3F_league_rules.html


For comments on 4.1 and other comments by Ken, they were actually already addressed in the FAI rules shown
http://www.hkrcss.org/F3F_rules.html


The writing for Allan's comment on 4.3 is bit different. I think there are always confusion if a pilot and his helper can request an abortion and re-flight during his run. Instead I think the pilot should try to complete the course first, if he choose to abort, he should only be allowed to make a request for re-flight after the abortion. It is up to the CD decision to grant the re-flight. Everybody including helpers, onlookers, must be kept queit during a pilot's run.


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PostPosted: 05 Jan 2008 12:06 am 
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I have preliminary generated an assignment table for the contest administration teams for the league. I based on the assumption that we have 12 constant participants. Everybody can have a chance to be a CD. I am not sure Y.C. will come more often or not, so he may be reserved as a backup in case any of you are busy that day. If the dates are not acceptable to you, please raise your request for change and I will update the table to suit everybody's schedule before the league started. After the table has been fixed, any change will be based on swapping with a mutual conscience from fellow pilots concerned.

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PostPosted: 05 Jan 2008 04:54 pm 
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Concerning 4.3 Re-flight ... quote below ...

"Only the CD has the sole power to approve and announce a re-flight due to poor wind speed, judge errors, or other circumstances. The pilot himself or his helpers can not initiate a request for re-flight during his run. Abortion of flight is pilot's own decision. Any request for re-flight should be made only after an attempt to complete the course has been made. In any case, an approved re-flight should be executed at the end of the current round. Helpers, onlookers and other pilots not on the stage must keep quiet during a pilot's run in order to minimize disturbance to the contesting pilot. CD has the power to expel or disqualify anyone who breaks this regulation after repeat warning."

Would like to share that I have strong reservation on proposing "Any request for re-flight should be made only after an attempt to complete the course has been made" because:

a. For cases like timer linkage error, base judged error or paraglider interruption, all re-fly judgement can be made on-the-course, why not for during poor conditions ?!

b. Upon completion, the flight time will likely bais CD's judgement on weather a re-fly should be granted or not - for example : 80.xx sec - not bad and so no re-fly please !

c. Forcing pliots to complete the course (as a pre-requestion for re-fly) will risk their planes for continue sink into a irrcoverable condition or more riksy in crashing with paraglider if they jam on the track

d. Obviously during such non-flyable condition, even pilots struggled to complete the course - it will take longer time for them to land their planes - further delay the race

I believe the root of the issue is about guidelines to CD to better direct the race during marginal conditions (just above or below 3 m/s or cross wind)

For FAI rule "5.F.15. Interruptions: A round in progress must temporarily be interrupted if:- the wind force unintermittently is below 3 m/sec or more than 25 m/sec. (6 –55mph)"

My qusetions are:

1. Shall CD be making more proactive annoucment to pause the race if the conidtions are not deem flyable ?

2. Shall CD request asssitant CD to come to the front of slope to constant monitor wind speed and conditions - while CD is sitting at the back - and with assistant CD to inform CD if the current fly should cancel and immediate grant a re-fly ?

3. Shall all CDs adopt a common apporach to realize the "below 3 m/s", say if during pilots' plane two consecutive pass at the mid-point of the f3f track, the instant wind speed at that moment are below 3 m/s; then grant a re-fly immediately - just an idea but the point I would like to share is the need to have an common understanding on how to execute such "below 3 m/s" instead each CD just guess or feel by their own !

After all, let's look forward for better f3f conditions where re-fly should only apply to equipment error, judge error or paraglider interruption; rather than for struggling in marginal conditions :o

p.s. In the pass some helpers reported the wind speed on volunatry basis during marginal conditions - definitely helpful. I would like to thank them or otherwise I lost a lot of planes already :o


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PostPosted: 05 Jan 2008 07:34 pm 
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Hi Wing,

I share your view that if the pilot is only allowed to make a request for re-flight after landed may force the pilot to risk flying lower and lower. However, what we really worry is that if the pilot himself is busy in making the request and not concentrating on flying his plane, the situation is even worse. What I believe is the pilot should concentrate as much as possible on flying his plane, the decision to abort or not is up to CD and his team to do. In that sense, I think the assistant CD should constantly monitor the wind speed during a pilot’s run and make immediately action to announce abortion if situation may arrive. In any professional match, never we have the player to stop playing the game himself without the conscience of the judge.

To compromise, I think we can allow the pilot’s helper (remember in FAI rule each pilot can have a helper) to raise a request to CD during the pilot run. However, according to FAI rules, this helper can not talk to the pilot during run. So the pilot should let the helper to judge on making the request for re-flight and he himself entirely concentrates on flying.

In the view that we may not have one helper for each pilot, I would recommend that we should put the trust to the assistant CD to monitor the wind condition and make decision on abortion.

In some international contests, the pilot’s helper can raise a request immediately but I’ve never seen a pilot himself making the request.

So I re-phrased the wording a bit as:

"Only the CD has the sole power to approve and announce a re-flight due to poor wind speed, judge errors, or other circumstances. The pilot himself can not initiate a request for re-flight during his run. He should concentrate entirely on his flight. However, the pilot’s helper (or assistant CD) should monitor the wind condition constantly and raise any request for abortion immediately should situation may arise. A request for re-flight by the pilot can also be made after the plane was landed. In any case, an approved re-flight should be executed at the end of the current round. Helpers, onlookers and other pilots not on the stage must keep quiet during a pilot's run in order to minimize disturbance to the contesting pilot. CD has the power to expel or disqualify anyone who breaks this regulation after giving repeat warnings."

Will that be ok to all of you?


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PostPosted: 05 Jan 2008 08:57 pm 
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NO !

What if the pilot doesn't have a helper, or the helper requested for a reflight, but the pilot don't want it ?
My suggestion is to allow the pilot himself to request for a reflight, and wait for CD's decision.
The CD or assistant CD should monitor the condition at all time. They may issue a reflight option to the pilot during the race.
However, it's the pilots option to take a reflight or to keep his current score.


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PostPosted: 05 Jan 2008 09:45 pm 
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Different pilots have different tolerance in requesting abortion. If we allow the pilot to make request himself, then there will be lots of confusion and possible unfound requests since the cause of loosing attitude may be due to pilot's own fault, but he makes the request anyway. Then, there will be lots of confusing exchanges between the admin team and the pilot. In Viking Races, I haven't seen any pilot making the request himself during his flight. Instead the CD monitors the wind condition constantly and offers him an option to re-flight after the run was completed.

Why don't we trust the assistant CD to monitor the wind condition and make recommendation by him in a uniform manner. We should trust him for his professionalism in fairness.

I agree with Mak that the ultimate decision to abort is up to the pilot even an option for re-flight is granted right after wind condition is dropped below standard.

I would propose the following procedure for discussion then:

A pilot run started
Assistant CD monitors the wind condition constantly
Assistant CD raises a signal for possible re-flight if wind is sub-standard
CD announces to the pilot an offer for re-flight is made
Pilot’s decision
Option 1 -> to abort immediately and have the re-flight later
Option 2 -> to continue and complete the course, then check the timing, if he is not satisfied he can opt for a re-flight in later time

Can other pilots give your opinion please?


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PostPosted: 06 Jan 2008 01:48 am 

Joined: 02 Aug 2004 11:34 am
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[quote="Stanley"]


Option 2 -> to continue and complete the course, then check the timing, if he is not satisfied he can opt for a re-flight in later time

quote]
For Option 2, if the pilot decided to continue, the result has to be counted. It cannot be stood with if result is OK, take it. If not satisfactory, go for the re-fly. It's unfair to the pilots in the same round who had run their turn and have the results publicized, especially for those the scores of that round are close.
With the pilot's decision to continue with flying, even for the situation if the 10 legs cannot be completed after the poor flying condition info has been issued by the CD, the pilot has to admit with a DNF as the result.

The pilot should be the actual person who know whether he can manage and continue to fly.

Monitoring the wind direction and speed by the Assist CD and provide abort recommendation, if required, is really practical.


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PostPosted: 06 Jan 2008 02:28 am 
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OK. If the pilot is not allowed to ask for a re-flight. He can ask the CD to check wind condition, when he find it difficult to fly.

If a re-flight was offered. the pilot should take the offer before the end of the next leg.
After that chance, he must continue.


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PostPosted: 06 Jan 2008 10:26 pm 
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The debate on this issue of allowing the pilot to raise a request for re-flight during run can go on without a concrete solution.

How do the F3F flyers in other parts of the world handle this problem?
Are there any commonly agreed rules for this issue in world F3F community?

I think we should try to work out a compromised scheme practically next week in the first league race.
Perhaps, we can try both policies one round by one round next week to test which scheme works best practically and is acceptable to most of us.

For the time being, I re-wrote the wording as shown to allow a pilot to make request during his flight. But I still believe that we should follow the international de facto standard if there is any later on so that our league will be professionally run.

"Only the CD has the sole power to approve and announce a re-flight due to poor wind speed, judge errors, or other circumstances. The assistant CD should monitor the wind condition constantly. If the wind condition is below standard during flight, CD can issue an option for the pilot concerned to abort and to take a re-flight later. If the pilot chose to continue, there will be no re-flight for him no matter his run is successfully completed or not.
The pilot himself can also initiate a request for re-flight during his run if he thinks the wind condition is below standard. Having received the request, the assistant CD should check the wind condition and confirm with CD for granting or refusing the request. In any case, an approved re-flight should be executed at the end of the current round. Helpers, onlookers and other pilots not on the stage must keep quiet during a pilot's run in order to minimize disturbance to the contesting pilot. CD has the power to expel or disqualify anyone who breaks this regulation after giving repeat warnings."



Will that be ok for all of you? Please give your comments.


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PostPosted: 07 Jan 2008 07:29 pm 
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Hi Stanley and others, thanks for consolidating the comments and revising the idea. Deeply appreciate :o

Given not all f3f pilots have the opportunity to review this discussion on our forum. How about Stanley to help communicate this along the briefing session in next f3f race, perhaps also we further review if practical at the end of race :?:

Guess it may take a while for us to explore and refine that after few race afterwards. For example, take the past experience of butterfly deployment for re-fly (e.g. due to equipment error); most of us felt that buffterfly deployment is difficult and subjective to judge so right now we all adopt a clean landing and re-launch. So I guess as long as we have an initial idea to start with, we can leverage upcoming races to better before iron down as rules :o


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PostPosted: 08 Jan 2008 12:14 am 
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I think the rules are clear. Now, we have to make it practical. Firstly, we should have a clear briefing for CD and Assistant CD on their role and responsibility. Secondly, we need a stable wind meter, liked Ah Mak's model, which provides the average wind speed. Thirdly, we should mount it suitable for the CD and Assistant CD. Would YC please make one more base mount same as the one for point A & B.


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PostPosted: 08 Jan 2008 09:00 pm 
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Angus wrote:
... Would YC please make one more base mount same as the one for point A & B.


No problem. Is CM gonna incorporate wind speed reporting into the timer device ?


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PostPosted: 08 Jan 2008 09:21 pm 
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Hi,

I improve the writing for the incomplete race to avoid loophole of further confusion in case of poor weather for the continuing race. Here is

1.3 Incomplete races
A race is said to be incomplete if at least one round but less than four rounds are successfully run. Based on majority opinion on site, CD has the right to decide to cancel the race or to select another day to continue the race (normally, it will be one week later and must be agreed by all pilots on site). In case of cancellation, all the scores for the completed rounds will be discarded and voided. In case of continuation, the completed rounds will still be used to count for the final scores of this race.
If the weather forecast for the day of the continuing race is not promising, CD should cancel the race for all with no further re-scheduling.


Please comment if you think otherwise


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PostPosted: 08 Jan 2008 11:55 pm 
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Y C Lui wrote:
Angus wrote:
... Would YC please make one more base mount same as the one for point A & B.


No problem. Is CM gonna incorporate wind speed reporting into the timer device ?


YC you mentioned about me :x

Actions speak louder than words . . . Due to my bad record of project delay I tried to keep my mouth shut in this thread. Well, you are right that I am going to incorporate an anemometer to the timer. I can bring it to you this Sunday. I also have a tripod that I planned to convert it to mount the anemometer on. You can take it away too.

Image


By using the anemometer, we can do it like this:


1, The wind speed is measured continuously. However, the instantaneous value has not much help in determining the flying condition. Here we define "Wind speed" as the moving average of a 20 seconds window. (5.F.16, SC4_Vol_F3_Soaring_08)

1.1, Whenever the moving average is reset, wind speed will not be available until after 20 seconds.


2, If the wind speed (i.e., 20 seconds windows) is within the limits (3 - 25m/s), CD can announce the order for start:

2.1, CD calls the competitor to start. CD presses a key on the timer. Timer starts 30 seconds count down. Wind speed moving average reset.

2.2, If the wind speed is within the limits through out the 30 seconds count down time but the competitor does not launch the plane, he will get a DNS. (5.F.6)

2.3, If the wind speed is out of the limits in the 30 seconds, the count down will be stopped and the CD will announce for a hold of the starting procedure. Wind speed moving average reset. Restart procedure 2.


3, If the competitor successfully launched the plane in 2, CD will press the key again. Another 30 seconds count down started for gaining height. Wind speed moving average reset.


4, During the run (height gaining and speed course), if the wind speed is out of the limits the audio system will generate a brief beep sound.

4.1, If the wind speed returns to normal the beep will stop.

(Some discussion here)
4.2, Whenever the beep is heard, the competitor can request for a reflight at any time, even the wind speed returns to normal afterward.

or

4.2, The competitor can only request for a reflight when the beep is heard. If he does not do so and the wind speed returns to normal afterward he has to continue the flight.

or

4.2, The competitor must complete the course even though the wind speed has been out of the limits. After the course is completed, the timer will calculate the average wind speed during his run. If it is out of the limits the competitor is allowed for a reflight.


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PostPosted: 09 Jan 2008 02:24 pm 

Joined: 02 Aug 2004 11:34 am
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CM,
Do you need to get the timing equipment to upgrade the firm ware? Or you can get it done on the flying site? The timing equipment is being kept by me now.


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PostPosted: 09 Jan 2008 03:58 pm 
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Hi C.M.,

A few questions:

Why we need to reset the system and wait for 20s every time we measure the average wind speed? It seems very tedious.
To my understanding, the measured wind speed is the average of past 20s only. This is referred to the past only, no future. If we reset the meter, the measurement window is exactly the past 20 seconds, fine! But, to do that it is very tedious. I think practically, assuming the long-term wind speed is quite stable, the measured wind speed 20s before the start of the current measure is similar, then there is no need to reset the meter.

I am not sure also if the meter would have a forgetting factor, say, whenever a new sample is inputted, the old sample 20s before is removed. This kind of measurement is called a moving average with a window of 20s. Then we do not need to reset the meter.

Another question is: can we set the lowest wind speed limit for the system? Instead of 3m/s exact, can we, say, set it to 2.5m/s? Because different sites might have different limits, some sites with a 2.5m/s wind is definitely flyable. Also, there may be practical problem in setting the wind meter pole for a sufficient height or out, the measurement may be lower than the actually wind speed. I think provide that we keep the lower limit unchanged over the whole contest, this may be ok.


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PostPosted: 09 Jan 2008 06:26 pm 
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Stanley wrote:
Hi C.M.,

Why we need to reset the system and wait for 20s every time we measure the average wind speed?

Can we set the lowest wind speed limit for the system? Instead of 3m/s exact, can we, say, set it to 2.5m/s?


I share the same questions. For 20s moving average, FIFO data, it should not be necessary to reset the system. Fixed 3m/s setting is too rigid and may not accommodate our usual light condition. Two steps, 3m/s and 2.5m/s, are enough. In order to get accurate measurement, the anometer should be placed either in front of the slope or in very high position behind the pilot. This is why I ask YC to prepare another mount for the anometer using fish pole of 3-4m height.


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PostPosted: 09 Jan 2008 06:28 pm 
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Hi Yeung,

Please keep the timer until this Sunday, I have not yet started the software change! :x


Hi Stanley,

I try to reply point by point. Hope it is easier to understand.


1, We can adjust the two limits.


2, As long as the position of the anemometer does not change through out the contest, every competitors will reference to the same system. I think it is fair enough.


3, The 20sec average is a moving average (didn't I make it clear??): Vave(n) = ( 1 / 20 ) * SUM [ V(n) .. V(n-(20-1)) ]. And so the input 20sec before will be discarded.


4, Reset of the moving average is done automatically when the CD presses a key to start the timer. In practice it will not increase the work load of the CD.


5, Note that a "Start phase" is added. When the CD announces a start order, the competitor must launch the plane within 30 seconds. This is stated in FAI rules but had not been carried out in our previous contests. So now the CD need to press the key twice instead of one: one for the announcement of the start of an attempt, another for the launch of the plane.


6, About reseting of the moving average, I am thinking of the problems that can happen in the marginal condition. For easier to understand, let's reduce the moving average to 5 sec windows and sampling rate is 1 sample / second.

If we do not reset the moving average after the start order is announced . . .

Example 1:
3 3 3 3 3 (ave=3, Start order announced). Now any new sample below 3 will cause the average drops below 3 and cause a restart.
For example: 3 3 3 3 3 (ave=3, Start order announced) 2 (ave=2.8, Start phase terminated). Actually we do not know if the wind speed afterward is good or bad. If the actual wind speed is like the following then we lose a chance of legal start: 3 3 3 3 3 (Start order announced) 2 3 4 3 3 3 3 3 3 3 .. . (average is 3 in the 30 sec count down period)

Example 2:
5 3 2 2 3 (Ave=3, start order announced). Note that even the wind speed samples after the start order is announced are all >= 3, the average is still possible to drop below 3 and cause a restart.
For example: 5 3 2 2 3 (ave=3, Start order announced) 3 (ave=2.6, Start phase terminated). As in example 1, the actual wind speed may be completely within limits in the coming 30 sec but we lose another legal start: 5 3 2 2 3 (Start order announced) 3 3 3 3 3 3 3 3 . . . (average is 3 in the 30 sec count down period).

So I think it is necessary to reset the moving average to prevent wrong decision caused by the old wind speed samples.

Similar reason for reseting the moving average after the plane is launched. We do not want the wind speed while the model is still on the ground has anything to do with the abort decision.


7, After the start order is announced, there is no wind speed to report until the last 10 seconds. It is up to the competitor's decision if he wants to launch the plane in the first 20 seconds. If he think the wind is too weak to launch, he has to wait for 20 seconds.


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PostPosted: 09 Jan 2008 10:21 pm 
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Hi C.M.,

Just talked to Ah Pong and he pointed out that, we need to read the FAI rules 5.F.16 carefully,
b) fewer than 50% of the competitors have been able to perform the task caused by marginal conditions. Without the condition "constantly" (i.e. 20 seconds) have been met and thus caused re-flights.

The word “constantly” in this sentence really means if within the 20 second window, all measurements are beyond limit (<3m/s or >25m/s), the system should sound an alarm and automatically cause a re-flight.


The consequence of this correct interpretation is as follows:

1. We should build a device that count the wind speed for a 20s window, if all measurements within this window is out of limit, the device will sound an alarm

2. There is no need for the pilot on flight to request for re-flight, re-flight is automatic if the device sound an alarm

3. For the 30s start time, the device should continue to monitor the wind and the pilot must launch within this window if no alarm is sounded


I think that will simplify a lot and the arguments we have about making request for re-flight is all useless.
I just wonder, how clever the world F3F flyers have achieved after years of experience and we’re just too immature, and new to experience this!

You know the word "constantly" in the sentence was "intermetantly" in the previous version. I have been wondering why they changed it for a long time and didn't really understand why until pointed out by Ah Pong - thanks, we solve the problem now, can CM build the system according to the specification?


Last edited by Stanley on 09 Jan 2008 10:23 pm, edited 1 time in total.

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PostPosted: 09 Jan 2008 10:21 pm 
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8) 8)
Dear all,

Just discussed with Stanley and CM. In fact, the FAI rule quote CONSTANTLY stead of AVERAGE. Therefore, the situations mentioned by CM above, in fact is very simple.

However, by discussed with CM, I found the word ENTITLE for re-flight. So, if the alarm sounds, the pilot could still go ahead. He may take the result as normal if he feel OK. Entitle does not mean MUST have a re-flight.


8) 8)


Last edited by Ah Pong on 09 Jan 2008 10:26 pm, edited 1 time in total.

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