Is FLARM helpful?

On Friday, November 27, 2015 at 6:43:55 PM UTC-8, XC wrote:
The case that folks are making regarding high converging speeds are in clouds streets, wave and ridge lift. Theses are predictable situations that are easily handled by the FLARM algorithm. In the worse case scenario, 10-15 seconds is plenty of time to alter course to avoid a mid-air

Disagree - totally - this is inconsistent with experience.

The argument that a radio call to a known ID is the best course of action is false. The best way to avoid a mid-air is to turn to avoid the danger using predetermined right-of-way rules, not to establish radio communication and coordinate a plan.

Ask anyone who it has happened to. "XC please turn right" beats guessing which way you are going to go and even the Flarm guys recommend strongly agains making an impulsive turn because even if both glider guess to turn away from each other it turns their wings into a perfect "X". Not good.


Lastly, good glider pilots don't stumble into saves. They know where the lift is likely to be. They manage risk to get there with altitude to use it and have a back up plan. Some people are good at this and others are not as good. The score sheet should reflect this fact. The rules should ensure the integrity of the sport and keep it the adventure it was always supposed to be - not water it down. You'd attract a lot more people to the sport by having soaring heroes like we used to have rather than trying to placate everyone's desire to make it home for dinner.

This is folklore - if you really believed that we should devalue speed days and not devalue days where one "hero" gets around and everyone else lands out - yet we do the opposite. Look at Elmira - many of the top PRL guys got knocked out on the landout days. I'd say bunk to the contention that superior skill has very much to do with it above a certain level of experience.

9B

On Friday, November 27, 2015 at 7:43:55 PM UTC-7, XC wrote:
The case that folks are making regarding high converging speeds are in clouds streets, wave and ridge lift. Theses are predictable situations that are easily handled by the FLARM algorithm. In the worse case scenario, 10-15 seconds is plenty of time to alter course to avoid a mid-air

The argument that a radio call to a known ID is the best course of action is false. The best way to avoid a mid-air is to turn to avoid the danger using predetermined right-of-way rules, not to establish radio communication and coordinate a plan.

Lastly, good glider pilots don't stumble into saves. They know where the lift is likely to be. They manage risk to get there with altitude to use it and have a back up plan. Some people are good at this and others are not as good. The score sheet should reflect this fact. The rules should ensure the integrity of the sport and keep it the adventure it was always supposed to be - not water it down. You'd attract a lot more people to the sport by having soaring heroes like we used to have rather than trying to placate everyone's desire to make it home for dinner.

XC

Sean,

I have seen several days at Nephi in the last two years plus many days at Parowan and Uvalde where 15 to 20 seconds is marginal for planning. While I really like Flarm, I also recognize that interpreting a warning and then deciding how to respond takes time and can be very disconcerting at high speeds. I am still not used to the fact that I have to pull my focus back in the cockpit just when I really need to be scanning for the traffic.

Two years ago on a contest day we had a single street the last few miles into and out of the first turnpoint. We were flying at over 110 knots indicated at about 13,000 feet. I was flying with IRS (Mark) on my right wing and fortunately we had about five miles Flarm range because we were head-on and same altitude with 9B (Andy) and ZL (Dave) running at the same speed in the opposite direction. Andy and I were coordinating from about 4 miles apart to maintain separation but I still never saw ZL when the two passed. Andy went between Mark and me both horizontally and vertically with only a hundred feet vertical separation (I show IRS and 9B as close as 4 feet vertically as we passed). It would be easy to turn to avoid one warning only to cross the path of a second glider if you did not know they were coming.


I don't have a perfect answer on the stealth versus not discussion. I understand that non-stealth changes the game dramatically but I also like having more warning time to prepare for meeting other gliders when we are closing at 250 mph. I am not ready to make stealth required at all contests until we have some experience with it under western conditions.

Tim

My math is correct, my typing was not: 1/4 of a minute warning! That is actually not much time to be alerted, accept the alert, come up with a plan of action and react. This is why it is better to have Flarm set you can see the gliders coming your way, while there is enough to plan not just react. Western flying at speed and altitude under mountain generated clouds streets is different than eastern flying, and requires its own set of safety parameters and flying style. Not every peg fits in every hole.


On Friday, November 27, 2015 at 12:49:53 PM UTC-8, wrote:
"The $PFLAA sentence is info about proximate aircraft displayed on your device. In stealth mode this info limited to aircraft within 2 km and +/- 300 meters vertically. Stealth or competition mode also removes ID, climb rate, track and speed from the display output for these proximate aircraft. It continues to use these variables to calculate the collision avoidance algorithm in $PFLAU. "

Imagine two gliders flying in Utah at the nationals at 17,000 feet 100 knots indicated under cloud street on opposite courses. Say the 100 knots indicated is 134 knots true. Closure rate 268 knots or 496 kph, covering 2Km is about 1/4 a second warning. Just saying.



On Friday, November 27, 2015 at 11:57:18 AM UTC-8, XC wrote:
I am still seeing a lot of misinformation out there. I have two points to make supporting the use FLARM stealth mode in contests.

1) Stealth mode still allows the display and audio warning for threat aircraft no matter what the range.

and

2) FLARM used without stealth mode leads to an invalid score sheet. This is more true in eastern U.S. or European contests with lower working bands and more potential landouts.


First, I'd like folks to understand that FLARM sends two different messages to the display devices.

The $PFLAU sentence has priority and contains info about intruder alerts and obstacles. The contest ID is removed in stealth mode. Alerts are unaffected no matter the range. It really works quite well with the algorithm the FLARM people have developed.

The $PFLAA sentence is info about proximate aircraft displayed on your device. In stealth mode this info limited to aircraft within 2 km and +/- 300 meters vertically. Stealth or competition mode also removes ID, climb rate, track and speed from the display output for these proximate aircraft. It continues to use these variables to calculate the collision avoidance algorithm in $PFLAU.

Folks should read FLARM release notes for FLARM 6.02 Firmware, FLARM data port specification TFD-12 and FTD-14 FLARM Configuration Specification for full understanding. Anyway, we found in Elmira last year it worked quite well and the contest was definitely still fun for all.

High Western conditions versus lower Eastern (US) conditions: Without the use of stealth mode, in a contest with a lower working band, a pilot relying on FLARM technology can drive harder without fearing a landout, knowing there are gliders ahead to mark thermals. This does work in the east where thermals are closer together and you may be one thermal away from a landout. Even a mediocre pilot who might not even be able to get around the course by him/herself that day can use FLARM to pick the best thermals, found by others, and do fairly well on the score sheet. I agree in most cases this will not get a pilot the win. I do believe FLARM without stealth mode jumbles the middle of the score sheet and leads to an invalid result.

So, do what you want when flying cross countries at home. However, I go to contests to see how I am stacking up against some great pilots. Stealth mode (soon to have more appropriate name) is the way to go here. It retains all the safety features it was designed to deliver, keeps your eyes outside of the cockpit where they should be and at the end of the contest period the score sheet shows which pilots have the best soaring skills.

XC

1/4 minute is ample time - that is about when Flarm issues its first acoustic collision alert. I have participated in several head on collision scenarios during a Flarm trial. Even waiting until the third level of Flarm alarm before reacting all that is required is a gentle change of direction a few degrees. The key thing is that Flarm has alerted you to visually acquire the potential threat that you might not otherwise have done.

BTW my strong belief is the the first response to a Flarm acoustic alert should be to look along track, to see a possible head on threat, before looking at the visual display. Head on threats are the most high energy.

There is far too much concentration on Flarm visual displays (eyes down) instead of the acoustic alert (eyes outside).

On Friday, November 27, 2015 at 11:32:31 PM UTC-5, Tim Taylor wrote:
On Friday, November 27, 2015 at 7:43:55 PM UTC-7, XC wrote:
The case that folks are making regarding high converging speeds are in clouds streets, wave and ridge lift. Theses are predictable situations that are easily handled by the FLARM algorithm. In the worse case scenario, 10-15 seconds is plenty of time to alter course to avoid a mid-air

The argument that a radio call to a known ID is the best course of action is false. The best way to avoid a mid-air is to turn to avoid the danger using predetermined right-of-way rules, not to establish radio communication and coordinate a plan.

Lastly, good glider pilots don't stumble into saves. They know where the lift is likely to be. They manage risk to get there with altitude to use it and have a back up plan. Some people are good at this and others are not as good. The score sheet should reflect this fact. The rules should ensure the integrity of the sport and keep it the adventure it was always supposed to be - not water it down. You'd attract a lot more people to the sport by having soaring heroes like we used to have rather than trying to placate everyone's desire to make it home for dinner.

XC

Sean,

I have seen several days at Nephi in the last two years plus many days at Parowan and Uvalde where 15 to 20 seconds is marginal for planning. While I really like Flarm, I also recognize that interpreting a warning and then deciding how to respond takes time and can be very disconcerting at high speeds. I am still not used to the fact that I have to pull my focus back in the cockpit just when I really need to be scanning for the traffic.

Two years ago on a contest day we had a single street the last few miles into and out of the first turnpoint. We were flying at over 110 knots indicated at about 13,000 feet. I was flying with IRS (Mark) on my right wing and fortunately we had about five miles Flarm range because we were head-on and same altitude with 9B (Andy) and ZL (Dave) running at the same speed in the opposite direction. Andy and I were coordinating from about 4 miles apart to maintain separation but I still never saw ZL when the two passed. Andy went between Mark and me both horizontally and vertically with only a hundred feet vertical separation (I show IRS and 9B as close as 4 feet vertically as we passed). It would be easy to turn to avoid one warning only to cross the path of a second glider if you did not know they were coming.


I don't have a perfect answer on the stealth versus not discussion. I understand that non-stealth changes the game dramatically but I also like having more warning time to prepare for meeting other gliders when we are closing at 250 mph. I am not ready to make stealth required at all contests until we have some experience with it under western conditions.

Tim

I sounds like coordination between gliders has limited usefulness. It involves several extra steps, heads down time, plus everyone has to be working together. I agree with the fellow who said audio warning plus eyes outside is the best way to go.

Have you tried stealth mode in a contest? It works well. Try it and I think you find it is fine.

Perhaps a better path for you and Andy would be to get involved in the ongoing discussion about the best range to show proximate traffic in competition (stealth) mode. (Remember intruder traffic is displayed at any range the FLARM set up can detect). Perhaps the range should be configurable to show proximate traffic farther away in western contests. The algorithm could also be modified to identify more threats. These are all possibilities. I still see no need to display contest ID, climb rate, i.e. all the competitive stuff. Relative altitude is displayed.

Also, I think we can agree a few degrees of bank is all that is need to avoid traffic at 110 kts.

XC

I have some experience of head-on meetings under cloud streets and narrowly avoided a couple of collisions in my pre-Flarm days. Closing speeds are impressively high and the interval between seeing a glider head-on and avoiding it impressively short. Fifteen seconds warning is almost certain to be a lot better than you have visually.

However, I cannot understand how anyone believes that reducing the amount of information on glider positions by using stealth mode does anything other than reduce safety. I believe the concern over leeching is seriously misplaced.

Mike

On Saturday, November 28, 2015 at 9:36:31 AM UTC-5, Mike the Strike wrote:
I have some experience of head-on meetings under cloud streets and narrowly avoided a couple of collisions in my pre-Flarm days. Closing speeds are impressively high and the interval between seeing a glider head-on and avoiding it impressively short. Fifteen seconds warning is almost certain to be a lot better than you have visually.

However, I cannot understand how anyone believes that reducing the amount of information on glider positions by using stealth mode does anything other than reduce safety. I believe the concern over leeching is seriously misplaced.

Mike

An issue with this argument is the assumption that integrating an in-cockpit display into ones awareness has no cost. I believe this is a fallacy. Anything that directs your attention inside the glider potentially adversely affects safety. Folks are making the "situational awareness" argument with the premise that sll objects you need to be aware of are FLARM equipped and that all FLARMs are operating correctly.

WRT thermals, one prior poster observed that Winpilot is excellent for displaying gliders in a thermal. The idea of someone in a thermal not looking out the window 100% of the time is troubling to me. There have been at least two instances I am personally aware of where FLARM equipped gliders have collided in a thermal.

QT

"So whats wrong with flying 2/3 circles, I often circle in wave. In any case
Paolo Ventrafridda developed a method for LK8000, of flying S & L on one of
several headings for say 10 secs at a constant airspeed.
If the will is there, it can be done, and even if slightly imperfect, it
would be better than the present almost always wrong indication.
However another approach would be a way of manually putting the wind into
Flarm, using the vario/navigator readout, which I'm sure everyone flying
with Flarm, is equipped with as well. "

Nothing wrong with circling, but pilots aren't going to stop and circle just to improve the accuracy of their wind calculation. It comes down the to quality of the data being fed to the device. Whether derived internally or fed from an external source (such as the PNA's you suggest), unless it's always accurate it, it's going to result in inaccurate relative bearing information. To the best of my knowledge, Flarm presently resolves traffic warnings as a relative bearing based on *track*. It may not always be accurate with regards to *heading* but at least it's consistent and thus can be allowed for by the pilot. The only time things go to pot is when roughly holding position in wave. If Flarm was alternating between heading and track based relative bearings, based on the accuracy of the wind solution at the time, you'd never know where to look.

CJ

Sean, you say you're against using Flarm in non-stealth mode because "it leads to an invalid score sheet", essentially arguing that mediocre pilots could use Flarm for electronic leeching.

You've been a superior contest pilot for long enough that I think you're forgetting (1) the intensive learning that happens during contests by mediocre pilots and (2) just why those mediocre pilots are at the contest. They're at the contest because they're trying to become better pilots, and they learn that by observing what superior pilots are doing.

I submit that Flarm, in addition to being a safety device, offers a superior method for observing where other gliders are located, allowing a mediocre pilot to learn better how to read the sky and terrain. It's possible that some could use Flarm for leeching, but that behavior would show up in the IGC files and could be easily dealt with (with an unsporting conduct penalty).

-John, Q3

On Friday, November 27, 2015 at 2:57:18 PM UTC-5, XC wrote:
I am still seeing a lot of misinformation out there. I have two points to make supporting the use FLARM stealth mode in contests.

1) Stealth mode still allows the display and audio warning for threat aircraft no matter what the range.

and

2) FLARM used without stealth mode leads to an invalid score sheet. This is more true in eastern U.S. or European contests with lower working bands and more potential landouts.


First, I'd like folks to understand that FLARM sends two different messages to the display devices.

The $PFLAU sentence has priority and contains info about intruder alerts and obstacles. The contest ID is removed in stealth mode. Alerts are unaffected no matter the range. It really works quite well with the algorithm the FLARM people have developed.

The $PFLAA sentence is info about proximate aircraft displayed on your device. In stealth mode this info limited to aircraft within 2 km and +/- 300 meters vertically. Stealth or competition mode also removes ID, climb rate, track and speed from the display output for these proximate aircraft. It continues to use these variables to calculate the collision avoidance algorithm in $PFLAU.

Folks should read FLARM release notes for FLARM 6.02 Firmware, FLARM data port specification TFD-12 and FTD-14 FLARM Configuration Specification for full understanding. Anyway, we found in Elmira last year it worked quite well and the contest was definitely still fun for all.

High Western conditions versus lower Eastern (US) conditions: Without the use of stealth mode, in a contest with a lower working band, a pilot relying on FLARM technology can drive harder without fearing a landout, knowing there are gliders ahead to mark thermals. This does work in the east where thermals are closer together and you may be one thermal away from a landout.. Even a mediocre pilot who might not even be able to get around the course by him/herself that day can use FLARM to pick the best thermals, found by others, and do fairly well on the score sheet. I agree in most cases this will not get a pilot the win. I do believe FLARM without stealth mode jumbles the middle of the score sheet and leads to an invalid result.

So, do what you want when flying cross countries at home. However, I go to contests to see how I am stacking up against some great pilots. Stealth mode (soon to have more appropriate name) is the way to go here. It retains all the safety features it was designed to deliver, keeps your eyes outside of the cockpit where they should be and at the end of the contest period the score sheet shows which pilots have the best soaring skills.

XC

On Saturday, November 28, 2015 at 7:50:01 AM UTC-8, John Carlyle wrote:
Sean, you say you're against using Flarm in non-stealth mode because "it leads to an invalid score sheet", essentially arguing that mediocre pilots could use Flarm for electronic leeching.

You've been a superior contest pilot for long enough that I think you're forgetting (1) the intensive learning that happens during contests by mediocre pilots and (2) just why those mediocre pilots are at the contest. They're at the contest because they're trying to become better pilots, and they learn that by observing what superior pilots are doing.

I submit that Flarm, in addition to being a safety device, offers a superior method for observing where other gliders are located, allowing a mediocre pilot to learn better how to read the sky and terrain. It's possible that some could use Flarm for leeching, but that behavior would show up in the IGC files and could be easily dealt with (with an unsporting conduct penalty).

-John, Q3

On Friday, November 27, 2015 at 2:57:18 PM UTC-5, XC wrote:
I am still seeing a lot of misinformation out there. I have two points to make supporting the use FLARM stealth mode in contests.

1) Stealth mode still allows the display and audio warning for threat aircraft no matter what the range.

and

2) FLARM used without stealth mode leads to an invalid score sheet. This is more true in eastern U.S. or European contests with lower working bands and more potential landouts.


First, I'd like folks to understand that FLARM sends two different messages to the display devices.

The $PFLAU sentence has priority and contains info about intruder alerts and obstacles. The contest ID is removed in stealth mode. Alerts are unaffected no matter the range. It really works quite well with the algorithm the FLARM people have developed.

The $PFLAA sentence is info about proximate aircraft displayed on your device. In stealth mode this info limited to aircraft within 2 km and +/- 300 meters vertically. Stealth or competition mode also removes ID, climb rate, track and speed from the display output for these proximate aircraft. It continues to use these variables to calculate the collision avoidance algorithm in $PFLAU.

Folks should read FLARM release notes for FLARM 6.02 Firmware, FLARM data port specification TFD-12 and FTD-14 FLARM Configuration Specification for full understanding. Anyway, we found in Elmira last year it worked quite well and the contest was definitely still fun for all.

High Western conditions versus lower Eastern (US) conditions: Without the use of stealth mode, in a contest with a lower working band, a pilot relying on FLARM technology can drive harder without fearing a landout, knowing there are gliders ahead to mark thermals. This does work in the east where thermals are closer together and you may be one thermal away from a landout. Even a mediocre pilot who might not even be able to get around the course by him/herself that day can use FLARM to pick the best thermals, found by others, and do fairly well on the score sheet. I agree in most cases this will not get a pilot the win. I do believe FLARM without stealth mode jumbles the middle of the score sheet and leads to an invalid result.

So, do what you want when flying cross countries at home. However, I go to contests to see how I am stacking up against some great pilots. Stealth mode (soon to have more appropriate name) is the way to go here. It retains all the safety features it was designed to deliver, keeps your eyes outside of the cockpit where they should be and at the end of the contest period the score sheet shows which pilots have the best soaring skills.

XC

John,

I agree, but! Why would we want to allow mediocre pilots to get a chance for all the woman and money?

This is a game for enjoyment and those that think differently are already racing very few like minded pilots.

Richard