FLARM in Stealth Mode at US 15M/Standard Nationals - Loved It!

On Thursday, August 6, 2015 at 8:28:24 PM UTC-4, Andy Blackburn wrote:
On Thursday, August 6, 2015 at 7:40:21 AM UTC-7, Andy Blackburn wrote:

We now have at least one contest we can compare the results from to see if pilots scored significantly differently with stealth vs not - there is normally a lot of variance in the scoring even over a long contest so it may or may not show anything but at least we will have an indication if anything significant is going on.


I ran some numbers to test the theory that less skilled pilots use Flarm as a way to up their performance - and that Stealth mode helps negate this strategy. I compare the last two 15 Meter Nationals - 2014 at Montague (Flarm without Stealth Mode) and 2015 at Harris Hill (Flarm with Stealth Mode). I compared each pilot's performance as measured by final score as a percentage of winner's score to their PRL percentage, which is the longer-term average of the same metric and is used for US Team selection so it's the best available measure of overall pilot skill. The metric I used was average absolute error for each contest - on average how closely did contest performance match PRL percentage. I dropped from the analysis any pilots who withdrew from either contest.

The theory we are testing is that with unrestricted Flarm you should get more inexperienced pilots higher in the scoresheet with higher scores and potentially some of the more highly skilled pilots dropping down as a result..

The average absolute error for the 2014 15-Meter Nationals at Montague was 7.4%. That is, on average pilots scored only 7.4% off of their PRL. Four pilots were competing in Standard Class gliders at Montague without handicaps. If I give them each a 4% handicap the average absolute error drops to 7..1%.

The 2015 15-Meter Nationals at Harris Hill had an average absolute error of 11.8%. That a significant difference and not in the direction you'd expect. It turns out that at Harris Hill a number of highly ranked pilots under-performed their PRL and a few lower-ranked pilots out-performed their PRL.

This is 35 pilots flying a total of 259 contest flights, so it's not a super big sample size, but not terrible given the stark difference. I also looked for any potential sources of sample bias - average pilot skill, contest length or devalued days. The two contests were pretty similar. Average PRL for Montague was .899 and Harris Hill was .906. Montague was 8 days and Harris Hill was 7 days. The average daily winner's score at Montague was 869 points and Harris Hill was 844 points. Not perfect, but pretty close.

So, if the theory is that Flarm allows lower skilled pilots to leech their way to the top of the score sheet and Stealth mode puts a lid on this behavior, the data suggests the opposite. In fact a number of long-time (30-40 years) highly ranked pilots under-performed their PRL with stealth mode. One potential reason for this is that more experienced pilots are actually better at making use of Flarm information than inexperienced pilots. The other theory is that Flarm helps reduce the random landouts that tend to scramble the scoresheet and actually reinforces stability and order.

Discuss.

9B

P.S. I already said that it's only 259 data points.

Weather variability is most likely a bigger factor than Flarm. To wit- SM, who never lands out got snookered multiple times at Elmira. Same with KS. Only 3 pilots completed all tasks assigned. I suspect the weather had a much bigger effect on performance variability from the expected than Stealth- or not- ever would.
It is also worth noting that FS, who has a lot of Flarm expertise relative to the rest of us, won 15M in Stealth. Would he have enhanced his advantage? I think so.
UH

On Thursday, August 6, 2015 at 5:40:12 PM UTC-7, wrote:
On Thursday, August 6, 2015 at 8:28:24 PM UTC-4, Andy Blackburn wrote:
On Thursday, August 6, 2015 at 7:40:21 AM UTC-7, Andy Blackburn wrote:

We now have at least one contest we can compare the results from to see if pilots scored significantly differently with stealth vs not - there is normally a lot of variance in the scoring even over a long contest so it may or may not show anything but at least we will have an indication if anything significant is going on.


I ran some numbers to test the theory that less skilled pilots use Flarm as a way to up their performance - and that Stealth mode helps negate this strategy. I compare the last two 15 Meter Nationals - 2014 at Montague (Flarm without Stealth Mode) and 2015 at Harris Hill (Flarm with Stealth Mode). I compared each pilot's performance as measured by final score as a percentage of winner's score to their PRL percentage, which is the longer-term average of the same metric and is used for US Team selection so it's the best available measure of overall pilot skill. The metric I used was average absolute error for each contest - on average how closely did contest performance match PRL percentage. I dropped from the analysis any pilots who withdrew from either contest.

The theory we are testing is that with unrestricted Flarm you should get more inexperienced pilots higher in the scoresheet with higher scores and potentially some of the more highly skilled pilots dropping down as a result.

The average absolute error for the 2014 15-Meter Nationals at Montague was 7.4%. That is, on average pilots scored only 7.4% off of their PRL. Four pilots were competing in Standard Class gliders at Montague without handicaps. If I give them each a 4% handicap the average absolute error drops to 7.1%.

The 2015 15-Meter Nationals at Harris Hill had an average absolute error of 11.8%. That a significant difference and not in the direction you'd expect. It turns out that at Harris Hill a number of highly ranked pilots under-performed their PRL and a few lower-ranked pilots out-performed their PRL.

This is 35 pilots flying a total of 259 contest flights, so it's not a super big sample size, but not terrible given the stark difference. I also looked for any potential sources of sample bias - average pilot skill, contest length or devalued days. The two contests were pretty similar. Average PRL for Montague was .899 and Harris Hill was .906. Montague was 8 days and Harris Hill was 7 days. The average daily winner's score at Montague was 869 points and Harris Hill was 844 points. Not perfect, but pretty close.

So, if the theory is that Flarm allows lower skilled pilots to leech their way to the top of the score sheet and Stealth mode puts a lid on this behavior, the data suggests the opposite. In fact a number of long-time (30-40 years) highly ranked pilots under-performed their PRL with stealth mode. One potential reason for this is that more experienced pilots are actually better at making use of Flarm information than inexperienced pilots. The other theory is that Flarm helps reduce the random landouts that tend to scramble the scoresheet and actually reinforces stability and order.

Discuss.

9B

P.S. I already said that it's only 259 data points.

Weather variability is most likely a bigger factor than Flarm. To wit- SM, who never lands out got snookered multiple times at Elmira. Same with KS. Only 3 pilots completed all tasks assigned. I suspect the weather had a much bigger effect on performance variability from the expected than Stealth- or not- ever would.
It is also worth noting that FS, who has a lot of Flarm expertise relative to the rest of us, won 15M in Stealth. Would he have enhanced his advantage? I think so.
UH

Well SM landed out on a 486 point day at Harris Hill and P7 landed out on a 850 point day at Montague (and scored even lower) so I'd say that was worse. Also, the landout day that caught the guys you mentioned also got the guy who won the contest, so I'd say that bit of weather variability didn't really scramble the field much and therefore wasn't much of a factor. Just to be sure, I took out the roughly 200 point benefit the finishers got over the landouts that day. The average standard error went from 11.8% to 12.9% - so it made it even worse.

There are always exceptional circumstances on any given day, but things tend to average out with enough days and the effects aren't as strong as people seem to remember.

The puzzling thing is that lower-ranked pilots out-performed with Stealth on and HH and despite a fair amount of weather randomness at Montague and a lot of low scratching in the mountains and blue holes - the middle ranked pilots weren't able to out-perform, so not only is the leeching theory not reflected in the data we have, but the data tilts a bit in the opposite direction - Stealth mode is actually associated with less consistent results.

Yes, only two contests - but if there was something seriously going wrong from using Flarm you'd not expect these results.

9B

I flew Montegue and loved it. Rex and Nowelle did a great job. If you haven't flown there go at the next opportunity!

There are several reasons why the numerical analysis presented has limited usefulness. I'll just mention two:

1) I don't believe most people last year at Montegue were using a complete FLARM view type set up. I flew the contest with FLARM (through ClearNav) as anti-collision only. This year many more pilots were outfitted with the whole set up.

2) The weather at Harris Hill was much more fickle and unforgiving than Montegue, no comparison. 7 or even 8 days were flyable but each had significant challenges that tripped up even the locals. The guys I would have picked to win all had problems, sometimes on the first leg. On Day 6 in 15m 14/21 pilots landed out on the first leg. Others chose well and scored big. This really blew the rankings out of the water but that was the reality of the weather that day.

Great time at both contests,
XC

Interesting discussion,

IMO, the tactical advantage FLARM provides contest pilots during competition is being highly over-rated here. The "problem" is (and always has been) that A) not everyone has one, B) wants to buy one or c) is able to efficiently process the information available. I see FLARM (tactically) as just another small variable in the equation of flying performance.

It can easily hurt as much (or more) than it can help. Nobody seems to mention this possibility. Hint, hint...maybe you want people to try and leech with FLARM and fail or at least degrade. Hmm.

I currently have an "economy" contest set up...Brick-SN10-Oudie with a separate FLARM view display. A "funny guy" (he knows who he is) recently referred to my panel as a beat up WWII fighter. He's right! My panel is clearly not a great combination for efficiently tracking FLARM targets, analysing climb rates, etc. I don't know the full capabilities of the LX9000 or ClearNav. I do understand that their presentations are more (FLARM) information "rich." One good thing I see about a potential U.S. stealth mode rule is that the real or perceived advantage of these advanced soaring computers (in terms of FLARM based situation awareness) would be reduced or eliminated.

The real advantages of FLARM tracking (as I see it) is not climb rates. I would not trust the number anyway. I want to see the other potential gliders climbing and see the actual cloud they are under, etc. It's just not as simple as that pack has 3 knots and the other has 5...lets go to the 5!

For me, the ability to identify individual "key" pilots in the pack ahead (or behind) and "bonus" identification of gliders that I would have otherwise missed if I had not seen a FLARM "blip" and started searching in the exact right spot are the practical advantages that FLARM provides. It is very hard to calculate the value of these capabilities.

My actual FLARM reception range has been 1-3 miles (3 at absolute most). My antennas are well installed, blah, blah, blah. I therefore leave my FLARMview range at 1 mile so that I have a good resolution for "close in" gliders. In other words, the long range value is so consistently low that a greater range setting almost always pointless. Apparently others are seeing more as in my opinion 1 mile is fairly low value tactically. I usually see these gliders far earlier than I see them on FLARM.

While managing the available FLARM information well can provide value, my experience is that this is rarely a "great" value. In fact, it is usually a distraction to put effort into trying.

With that (my belief that others are likely gaining more from the available FLARM information than I am) I would (selfishly) be happy to see the requirement of a stealth mode at future US (or FAI) contests. But overall I have concluded that the value FLARM provides is highly, highly over-rated.

Finally, for whomever said (last few posts) the FAI World Championship Level requires FLARM leeching proficiency to be successful...please expound with specific information on how you reached these conclusions. Do you have a list of specifics? Who gave you this list? What experience do you have?

Sean
7T

On Friday, August 7, 2015 at 12:09:26 AM UTC-4, Sean Fidler wrote:
Interesting discussion,

IMO, the tactical advantage FLARM provides contest pilots during competition is being highly over-rated here. The "problem" is (and always has been) that A) not everyone has one, B) wants to buy one or c) is able to efficiently process the information available. I see FLARM (tactically) as just another small variable in the equation of flying performance.

It can easily hurt as much (or more) than it can help. Nobody seems to mention this possibility. Hint, hint...maybe you want people to try and leech with FLARM and fail or at least degrade. Hmm.

I currently have an "economy" contest set up...Brick-SN10-Oudie with a separate FLARM view display. A "funny guy" (he knows who he is) recently referred to my panel as a beat up WWII fighter. He's right! My panel is clearly not a great combination for efficiently tracking FLARM targets, analysing climb rates, etc. I don't know the full capabilities of the LX9000 or ClearNav. I do understand that their presentations are more (FLARM) information "rich." One good thing I see about a potential U.S. stealth mode rule is that the real or perceived advantage of these advanced soaring computers (in terms of FLARM based situation awareness) would be reduced or eliminated.

The real advantages of FLARM tracking (as I see it) is not climb rates. I would not trust the number anyway. I want to see the other potential gliders climbing and see the actual cloud they are under, etc. It's just not as simple as that pack has 3 knots and the other has 5...lets go to the 5!

For me, the ability to identify individual "key" pilots in the pack ahead (or behind) and "bonus" identification of gliders that I would have otherwise missed if I had not seen a FLARM "blip" and started searching in the exact right spot are the practical advantages that FLARM provides. It is very hard to calculate the value of these capabilities.

My actual FLARM reception range has been 1-3 miles (3 at absolute most). My antennas are well installed, blah, blah, blah. I therefore leave my FLARMview range at 1 mile so that I have a good resolution for "close in" gliders. In other words, the long range value is so consistently low that a greater range setting almost always pointless. Apparently others are seeing more as in my opinion 1 mile is fairly low value tactically. I usually see these gliders far earlier than I see them on FLARM.

While managing the available FLARM information well can provide value, my experience is that this is rarely a "great" value. In fact, it is usually a distraction to put effort into trying.

With that (my belief that others are likely gaining more from the available FLARM information than I am) I would (selfishly) be happy to see the requirement of a stealth mode at future US (or FAI) contests. But overall I have concluded that the value FLARM provides is highly, highly over-rated.

Finally, for whomever said (last few posts) the FAI World Championship Level requires FLARM leeching proficiency to be successful...please expound with specific information on how you reached these conclusions. Do you have a list of specifics? Who gave you this list? What experience do you have?

Sean
7T

Hi Sean, it's andy (ND) brayer. hobbs, asw 20, young guy.

You might have taken my words too literally. my meaning is not that one must use "flarm leeching" to it's fullest extent in order to be world champion.. on the contrary, and with the understanding that you know all of this already; I think that in order to win, you need something else, something intangible, raw unadulterated talent. but that alone doesn't win it. i think we all agree that at the world level a completely individualistic approach is ineffective anymore, and that you are giving something up by flying as a lone wolf. as such, and in conjunction with sound team flying tactics, the information that can be garnered through complete use of flarm's capabilities is probably better considered than not. so while i don't have first person experience on a world level, or an actual list of specifics blessed by kawa, meuser, or sommer themselves, I do think the results of the team flying/information sharing mentality speak for themselves. to me--and i daresay others with a more impressive competitive resume--those results ought to include the intelligence gathered through complete use of flarm's capabilities. it does seem like leeching to be able to chose one thermal over another based on the fact that you know that frenchman is climbing in 6 knots, but the spaniard is only climbing in 4. now, from what i understand you say it isn't quite as accurate as that, and i accept that. on the other hand, i have heard from others who shall remain nameless that it is and that they've seen that movie played out.

Maybe the information gathered from flarm is overrated, maybe it isn't. who can say for sure? these are matters of opinion. i'm not sure whether i agree with you 100%, or not at all.

what is your assessment about what i've said?

andy
(ND)

On Friday, August 7, 2015 at 12:09:26 AM UTC-4, Sean Fidler wrote:
Interesting discussion,

IMO, the tactical advantage FLARM provides contest pilots during competition is being highly over-rated here. The "problem" is (and always has been) that A) not everyone has one, B) wants to buy one or c) is able to efficiently process the information available. I see FLARM (tactically) as just another small variable in the equation of flying performance.

It can easily hurt as much (or more) than it can help. Nobody seems to mention this possibility. Hint, hint...maybe you want people to try and leech with FLARM and fail or at least degrade. Hmm.

I currently have an "economy" contest set up...Brick-SN10-Oudie with a separate FLARM view display. A "funny guy" (he knows who he is) recently referred to my panel as a beat up WWII fighter. He's right! My panel is clearly not a great combination for efficiently tracking FLARM targets, analysing climb rates, etc. I don't know the full capabilities of the LX9000 or ClearNav. I do understand that their presentations are more (FLARM) information "rich." One good thing I see about a potential U.S. stealth mode rule is that the real or perceived advantage of these advanced soaring computers (in terms of FLARM based situation awareness) would be reduced or eliminated.

The real advantages of FLARM tracking (as I see it) is not climb rates. I would not trust the number anyway. I want to see the other potential gliders climbing and see the actual cloud they are under, etc. It's just not as simple as that pack has 3 knots and the other has 5...lets go to the 5!

For me, the ability to identify individual "key" pilots in the pack ahead (or behind) and "bonus" identification of gliders that I would have otherwise missed if I had not seen a FLARM "blip" and started searching in the exact right spot are the practical advantages that FLARM provides. It is very hard to calculate the value of these capabilities.

My actual FLARM reception range has been 1-3 miles (3 at absolute most). My antennas are well installed, blah, blah, blah. I therefore leave my FLARMview range at 1 mile so that I have a good resolution for "close in" gliders. In other words, the long range value is so consistently low that a greater range setting almost always pointless. Apparently others are seeing more as in my opinion 1 mile is fairly low value tactically. I usually see these gliders far earlier than I see them on FLARM.

While managing the available FLARM information well can provide value, my experience is that this is rarely a "great" value. In fact, it is usually a distraction to put effort into trying.

With that (my belief that others are likely gaining more from the available FLARM information than I am) I would (selfishly) be happy to see the requirement of a stealth mode at future US (or FAI) contests. But overall I have concluded that the value FLARM provides is highly, highly over-rated.

Finally, for whomever said (last few posts) the FAI World Championship Level requires FLARM leeching proficiency to be successful...please expound with specific information on how you reached these conclusions. Do you have a list of specifics? Who gave you this list? What experience do you have?

Sean
7T

Hi Sean, it's andy (ND) brayer. hobbs, asw 20, young guy.

You might have taken my words too literally. my meaning is not that one must use "flarm leeching" to it's fullest extent in order to be world champion.. on the contrary, and with the understanding that you know all of this already; I think that in order to win, you need something else, something intangible, raw unadulterated talent. but that alone doesn't win it. i think we all agree that at the world level a completely individualistic approach is ineffective anymore, and that you are giving something up by flying as a lone wolf. as such, and in conjunction with sound team flying tactics, the information that can be garnered through complete use of flarm's capabilities is probably better considered than not. so while i don't have first person experience on a world level, or an actual list of specifics blessed by kawa, meuser, or sommer themselves, I do think the results of the team flying/information sharing mentality speak for themselves. to me--and i daresay others with a more impressive competitive resume--those results ought to include the intelligence gathered through complete use of flarm's capabilities. it does seem cheap, it does seems like shameless leeching to be able to chose one thermal over another based on the fact that you know that frenchman is climbing in 6 knots, but the spaniard is only climbing in 4. a thermal finder would ruin the sport in my opinion, and in that instance it seems to be acting as one. But anyone including myself would to take advantage of that knowledge if it were at hand. now, from what i understand you say it isn't quite as accurate as that, and i accept that point of view. on the other hand, i have heard from others who shall remain nameless that say it is and that they've seen that movie played out. both are matters of opinion.
Maybe the information gathered from flarm is overrated, maybe it isn't. i think the possible scenarios are far too many and complex to dismiss the possibility of learning something useful, especially when trailing the leading in the world championships by 30 points.

what is your assessment about what i've said?

andy
(ND)

Andy-

I think you mean well and speak heartfelt words (along with the whole group here)...but I also feel most of this discussion is highly subjective. I would like to see at least some data or proof.

My questions were serious and (hopefully) meaningful. I did not mean to throw you under the bus. I was hoping to get some more information on the use of FLARM at the world level. I think that conversation may be a useful one here as it is more objective (assigned tasks, smaller turn areas, more even pilots, etc).

In the U.S., I honestly don't believe that FLARM has the slightest effect on the results. Some may try their hardest, but it's just to hard to do consistently. Also, FLARM data is the norm at the World Championship level and all but one U.S. Contest in all history. If we run off and adopt "stealth mode," we once again handicap our world level pilots by "watering down" the game.

Perhaps the elite, sophisticated world gliding teams (Germany, Poland, Britian, etc) would be able to do some damage with FLARM data. But good on them because the safety based FLARM technology is equally open to all parties, so it's a level playing field. Again, I see FLARM data as small part of the overall equation. As long as it's level for all, no problem. This is my view.

That said, I have recently heard "campfire stories" of very sophisticated, coordinated use of FLARM at world championships. "Hard to believe" stuff. As it is third hand and I was not there, I can't post it here, sorry. I have also heard the FAI is considering stealth mode requirements. So maybe there is real data out there on how this is changed results, etc. I was hoping to hear more about this and that was the reason for my questions.

I just don't hear any specifics here...I hear broad statements and assumptions.

Sorry to make you feel pinned down like that. Not my intention.

I really enjoyed meeting you at Hobbs and think you have a very bright future in soaring. I look forward to flying with you again soon!

Sean

On Friday, August 7, 2015 at 12:53:32 PM UTC-4, Sean Fidler wrote:
Andy-

I think you mean well and speak heartfelt words (along with the whole group here)...but I also feel most of this discussion is highly subjective. I would like to see at least some data or proof.

My questions were serious and (hopefully) meaningful. I did not mean to throw you under the bus. I was hoping to get some more information on the use of FLARM at the world level. I think that conversation may be a useful one here as it is more objective (assigned tasks, smaller turn areas, more even pilots, etc).

In the U.S., I honestly don't believe that FLARM has the slightest effect on the results. Some may try their hardest, but it's just to hard to do consistently. Also, FLARM data is the norm at the World Championship level and all but one U.S. Contest in all history. If we run off and adopt "stealth mode," we once again handicap our world level pilots by "watering down" the game.

Perhaps the elite, sophisticated world gliding teams (Germany, Poland, Britian, etc) would be able to do some damage with FLARM data. But good on them because the safety based FLARM technology is equally open to all parties, so it's a level playing field. Again, I see FLARM data as small part of the overall equation. As long as it's level for all, no problem. This is my view.

That said, I have recently heard "campfire stories" of very sophisticated, coordinated use of FLARM at world championships. "Hard to believe" stuff.. As it is third hand and I was not there, I can't post it here, sorry. I have also heard the FAI is considering stealth mode requirements. So maybe there is real data out there on how this is changed results, etc. I was hoping to hear more about this and that was the reason for my questions.

I just don't hear any specifics here...I hear broad statements and assumptions.

Sorry to make you feel pinned down like that. Not my intention.

I really enjoyed meeting you at Hobbs and think you have a very bright future in soaring. I look forward to flying with you again soon!

Sean

hey sean,

i didn't feel thrown under the bus or pinned down. i was happy to elaborate on my thoughts, since i made a pretty short statement that was contradictory to what i had previously written. this discussion is interesting to me, and i'm glad to take part in it/read everyone else's opinions. on that note, I agree that it IS a subjective discussion.

sadly i can't give you more first hand knowledge of flying with flarm at the world level... YET look forward to flying with you again too!

ND

On Friday, August 7, 2015 at 9:53:32 AM UTC-7, Sean Fidler wrote:

I just don't hear any specifics here...I hear broad statements and assumptions.


One last effort to put the data we have on the table. I removed Days 1 and 6 (mass landout days) from Harris Hill. This leaves only days that had high completion ratios - only P7, XC and BT flew both 2014 and 2015 15-Meter Nationals and could make informed judgements about how "randomizing" the conditions were for what remained (outside the two landout days, that is).

The result is Harris Hill had an average winners score of 952 versus 869 for Montague, so from a devaluation perspective dropping the two mass landout days makes Harris Hill quantitatively less random. Even so, pilot performance averaged 10% off of what you'd expect from the PRL versus 7% for Montague (and 6.5% if you exclude P7's "random" landout).

I'd add that at Montague I saw lots of pretty complete Flarm setups (I worked on a bunch - doing config files, RF testing and even installed my spare unit in a competitor's glider - which is why people kept seeing 9B in multiple places on course - heh heh). I'd have to say that I think many, if not most, pilots had the ability to use Flarm tactically - I certainly did when I could and there was even a protest based in part on use of Flarm data for tactical purposes. Flarm may not have been in use by everyone to 100% of its ultimate capability, but it was certainly in use by enough people that if it was making a big difference you ought to be able to detect something. HH randomness notwithstanding, the Montague results were pretty orderly - so Flarm leeches were not successfully crawling up the scoresheet - though some may have tried.

The data to-date provides no evidence that people are generating sustained benefit from tactical Flarm usage. In fact, the evidence is that people are NOT generating a sustained benefit. Maybe that will change with time and experience.

This discussion has raised another thought. The single biggest factor in randomizing scores away from what makes sense (at least based on the long term competition records of the pilots) is weather. It has been argued here that it is harder to pick up any signal from Flarm leeching with random weather noise in the scores from tricky days that land out most of the field except for a lucky few. So, should we be disallowing days where less than 2/3 or 3/4 of the fleet finishes? They say contests are won on the weak days, maybe that's bad thing?

I tend to agree with Sean (7T). There seems to be a lot of speculation and supposition and "anecdotalytics" floating about - on all sides. It does appear to me that Stealth mode retains enough warning range for most collision scenarios, but how restricting the broader situational view might cascade into a threat scenario under particular circumstances is unclear and I would want to know a lot more about that. For instance, I have already once mistaken a glider that didn't show up on Flarm for one that was a threat and mistakenly tracked the wrong target until way too late. I suspect trial lawyers don't care if Stealth is 99% as good as no Stealth in the event anything bad happens. That's a concern.

I also tend to agree with 7T in his view that tactical Flarm usage sometimes helps a bit, sometimes hurts a bit. In FAI-style team and gaggle flying it probably can be used to greater benefit as gaggle-hopping is a strategy that can win races (Sebastian Kawa has a view on this point). Gaggle-hopping is a strategy that may be enhanced by, but was not created by, Flarm. It's more a result of FAI scoring philosophy. In any event, the strategy is available to everyone. Also, with or without Flarm, flying more assigned tasks will likely generate more leeching behavior, so if you're opposed to leeching, you might not like ATs either.

I also don't buy the "expensive arms race" argument. Most US racing pilots have Flarm available to them today (if you're really poor I'll loan you my spare, or you can rent one). Most glider pilots have some sort of moving map display - whether it's an LX9000/ClearNav premium computer or an Oudie (basically the same software as the LX) or a smartphone running open source gliding software. They all have Flarm tracking basically for free and new Flarm features will be made available to the broad market (at least that's been the case so far). Turning features off won't make the devices or software any cheaper and they won't not develop them just because racing pilots don't like them - they're great for OLC/buddy flying.

That does leave us with what seems to be the essential point. Does Flarm increase or decrease (some might say ruin) the qualitative experience of glider racing? There's no better feeling than having a strategic inspiration, going off on your own and smoking the field. There's also something disheartening about struggling down low until you find the boomer that saves your day only to have the gaggle roll in right on top of you. Stories of pilots who leeched their way to the podium by following top pilots around have been part of soaring folklore as long as I can remember, but I don't generally think the people on the podium are second-rate and most scoresheets make sense to me most of the time. BUT, there is also GW's sentiment - and it does not seem so rare - that Flarm allows pilots to keep in touch with some of the field and generates more of a sense of racing and some camaraderie in a sport that can be isolating. He argues that that's more fun and makes the sport more accessible to new pilots, even if it doesn't catapult them to the top - or even middle - of the scoresheet. We struggle with limiting the shrinkage of the sport. I'd be curious to know whether newer racing pilots learn more quickly and enjoy the experience more when they can see more of what's going on out of course.

Good discussion - many useful points and perspectives.

9B

On Friday, August 7, 2015 at 12:53:32 PM UTC-4, Sean Fidler wrote:
... I have also heard the FAI is considering stealth mode requirements.

Further proof of a truly stupid idea...
But maybe it will keep them busy so they don't introduce an 11 meter class!