PowerFlarm and ADS-B solution, can we find one?

On Friday, January 8, 2016 at 5:36:33 AM UTC-8, wrote:
Rarely would this require more than a few hundred feet at most. Modern gliders get up to speed with very little loss of altitude.
What you are describing may be fun but it is not very efficient.
Pull ups obviously can and are more dynamic but even there smoothness pays off. UH

A little math would help - but this seems roughly right.

Any decending air outside a thermal would likely be more gentle than the rising air at the core. I have certainly found I could gain more than 1,000 feet within 15 or 20 seconds with a smooth pull-up into a strong thermal.

We are talking about having adequate closing time (of around 45 seconds) from first being put on the traffic screen until potential collision - and not being . A glider running in say 3 knots of sink at 110 kts will lose around 500 feet in 45 seconds and a glider pulling up into lift might gain 7-800 from the pull-up and another 3-500 from the lift over that time period for a total of 1500-1800 feet net change (assuming the run into the thermal didn't also have some lift). Anything less creates a scenario where you can sneak in outside of the altitude filter for stealth and come into view with less than the requisite 45 seconds. Less than 1200 or so and the surprise can be quite sudden - maybe 8-10 seconds.

Of course getting into lines of lift can yield many different scenarios - running storm shelves is a common tactic, but so is convergence and occasionally wave - all have pairings of strong lift and some level of sink and pairings of gliders maneuvering. The fact that sink tends to generate push-overs and lift tends to generate pull-ups means that the effects are amplified, rather than canceling, so you need to look at both together.

9B

On Friday, January 8, 2016 at 8:03:36 PM UTC-8, Dan Marotta wrote:
I'm with you, T8.



I read this exact strategy back in the 80s; I think it was in
Reichmann's book.* I couldn't wait to perform a Split-S through a
thermal.* I was a new guy and thought that would be cool.* The "come
to Jesus" meeting at the end of the day with the other occupants of
the thermal was, shall we say, enlightening.



So here's my take on this whole Flarm "stealth" thing:



Those who want stealth mode, don't want others to be able to
identify them and become remoras.* That seems a nicer word than
leeches.* They state the reasons for their opposition in clear
terms.



Those who don't want stealth mode want to be remoras but don't want
to admit it.* In an attempt to push their view, they fall back on
Mom, apple pie, children, lawyers, and safety.* We see the same
arguments all the time in other activities and they become more
unlikely and extreme with each round.




On 1/8/2016 3:59 AM, Tango Eight wrote:



On Thursday, January 7, 2016 at 10:24:34 PM UTC-5, jfitch wrote:


a correct strategy is to turn sharply 180 degrees from the intended departure direction and dive through the core so that you have maximum speed gain with minimum loss to traverse the sink.


No.

T8





--

Dan, 5J

Hahaaaaa!
New subject.
Jim

On Friday, January 8, 2016 at 10:03:36 PM UTC-6, Dan Marotta wrote:

So here's my take on this whole Flarm "stealth" thing:

Those who want stealth mode, don't want others to be able to
identify them and become remoras.* That seems a nicer word than
leeches.* They state the reasons for their opposition in clear
terms.

Those who don't want stealth mode want to be remoras but don't want
to admit it.* In an attempt to push their view, they fall back on
Mom, apple pie, children, lawyers, and safety.* We see the same
arguments all the time in other activities and they become more
unlikely and extreme with each round.

Dan, considering you don't fly with a PowerFlarm and don't currently race, your comments are somewhat simplistic.

I've had PF since the day it came out, and have raced with it (in your stomping grounds, by the way). I love the situational awareness it provides, and think it makes racing a lot more fun, as well as safer. If you carefully read all the threads on this subject, you find a few hard core "IT WILL RUIN RACING AS WE KNOW IT!!!" proponents of stealth, a few hard core "MANDATE STEALTH AND ILL NEVER RACE AGAIN", and a lot of "I really like full flarm SA and I worry about mid-airs, is there a way we can compromise? My personal take is that the leeching argument is way overblown with the attendance at US contests, otherwise everybody would be carrying binoculars and all the young guys with 20-10 eyes would be winning. And having picked up USAFA Duo's(all USAFA racing gliders have PF) head on co-altitude under a cloud street over 10 km on the nose, I REALLY dont want to give up that capability.

All this knashing of teeth about how to tweek "stealth" to "competition" that will please everybody seems pointless to me. As others have pointed out, ADS-B out is coming, and if a cheap 1090ES system for UAVs comes out soon, I bet you will see it explode in gliders, and with PF you will see all those guys regardless of stealth or competition modes.

Instead of whining, we should all embrace the new technology and the capability it brings, and find new ways to use it. Despite what many nay-sayers are claiming, for the average racing pilot full up flarm makes a contest more enjoyable and safer - and isn't that really the point of it?

You should borrow a portable PF and try it - you may find that opens your eyes on what is really flying around in your airspace - you'll be able to see those airliners deviate around you!

Cheers from cold, wet, dreary St Louis.

Kirk
66

On Friday, January 8, 2016 at 11:03:36 PM UTC-5, Dan Marotta wrote:
I'm with you, T8.



I read this exact strategy back in the 80s; I think it was in
Reichmann's book.* I couldn't wait to perform a Split-S through a
thermal.* I was a new guy and thought that would be cool.* The "come
to Jesus" meeting at the end of the day with the other occupants of
the thermal was, shall we say, enlightening.



So here's my take on this whole Flarm "stealth" thing:



Those who want stealth mode, don't want others to be able to
identify them and become remoras.* That seems a nicer word than
leeches.* They state the reasons for their opposition in clear
terms.



Those who don't want stealth mode want to be remoras but don't want
to admit it.* In an attempt to push their view, they fall back on
Mom, apple pie, children, lawyers, and safety.* We see the same
arguments all the time in other activities and they become more
unlikely and extreme with each round.




On 1/8/2016 3:59 AM, Tango Eight wrote:



On Thursday, January 7, 2016 at 10:24:34 PM UTC-5, jfitch wrote:


a correct strategy is to turn sharply 180 degrees from the intended departure direction and dive through the core so that you have maximum speed gain with minimum loss to traverse the sink.


No.

T8





--

Dan, 5J

Dan, I specifically asked to keep this thread clean from any comments not related to finding a solution. Please take your comments to another thread and argue there. These comments bring no value towards finding a solution. This thread was intended to bring people together to find a solution not to create another divide.

To all, let's not get engaged in questioning each other motives.

Regards,
Andrzej

Well said Kirk.

The premise of this thread, that there should be some acceptable way to degrade the behavior of a safety device is just off base. We should only be looking to Flarm folks for ways to improve safety performance. That is their mission - no nonsense, no confusion about goals please.

Hi Kirk,

Yes, I've towed you during at least one contest at Moriarty and I've
admired your LS-6.

Please understand that I don't "poo-poo" Flarm in my comments, I only
respond to the comments of some, which I believe are unreasonable or
downright wrong. I always welcome logical proofs like the math-based
analysis of the pull-up (in a previous thread).

And yes, I think Flarm is a great tool for situational awareness but I
don't think that knowing a blip's ID is a requirement for safety. And
I'm neither for nor against "stealth" mode - I don't care either way.
The idea of coordinating an escape plan with another aircraft 5 miles
away by radio is simply ludicrous. Remember when contests were fully
manned and there was no Flarm or GPS? I'm not against either, as a lot
of the folks here think, but I think a lot of the fun has gone and
that's the main reason I don't fly contests any more.

So why do I keep posting? It's out of a genuine concern that false
perceptions, unchallenged, will eventually become policy, and I don't
want any more policies.

On 1/9/2016 8:09 AM, kirk.stant wrote:
On Friday, January 8, 2016 at 10:03:36 PM UTC-6, Dan Marotta wrote:

So here's my take on this whole Flarm "stealth" thing:
Those who want stealth mode, don't want others to be able to
identify them and become remoras. That seems a nicer word than
leeches. They state the reasons for their opposition in clear
terms.
Those who don't want stealth mode want to be remoras but don't want
to admit it. In an attempt to push their view, they fall back on
Mom, apple pie, children, lawyers, and safety. We see the same
arguments all the time in other activities and they become more
unlikely and extreme with each round.
Dan, considering you don't fly with a PowerFlarm and don't currently race, your comments are somewhat simplistic.

I've had PF since the day it came out, and have raced with it (in your stomping grounds, by the way). I love the situational awareness it provides, and think it makes racing a lot more fun, as well as safer. If you carefully read all the threads on this subject, you find a few hard core "IT WILL RUIN RACING AS WE KNOW IT!!!" proponents of stealth, a few hard core "MANDATE STEALTH AND ILL NEVER RACE AGAIN", and a lot of "I really like full flarm SA and I worry about mid-airs, is there a way we can compromise? My personal take is that the leeching argument is way overblown with the attendance at US contests, otherwise everybody would be carrying binoculars and all the young guys with 20-10 eyes would be winning. And having picked up USAFA Duo's(all USAFA racing gliders have PF) head on co-altitude under a cloud street over 10 km on the nose, I REALLY dont want to give up that capability.

All this knashing of teeth about how to tweek "stealth" to "competition" that will please everybody seems pointless to me. As others have pointed out, ADS-B out is coming, and if a cheap 1090ES system for UAVs comes out soon, I bet you will see it explode in gliders, and with PF you will see all those guys regardless of stealth or competition modes.

Instead of whining, we should all embrace the new technology and the capability it brings, and find new ways to use it. Despite what many nay-sayers are claiming, for the average racing pilot full up flarm makes a contest more enjoyable and safer - and isn't that really the point of it?

You should borrow a portable PF and try it - you may find that opens your eyes on what is really flying around in your airspace - you'll be able to see those airliners deviate around you!

Cheers from cold, wet, dreary St Louis.

Kirk
66

--
Dan, 5J

On Saturday, January 9, 2016 at 12:14:07 PM UTC-5, Dan Marotta wrote:
Hi Kirk,



Yes, I've towed you during at least one contest at Moriarty and I've
admired your LS-6.



Please understand that I don't "poo-poo" Flarm in my comments, I
only respond to the comments of some, which I believe are
unreasonable or downright wrong.* I always welcome logical proofs
like the math-based analysis of the pull-up (in a previous thread).



And yes, I think Flarm is a great tool for situational awareness but
I don't think that knowing a blip's ID is a requirement for safety.*
And I'm neither for nor against "stealth" mode - I don't care either
way.* The idea of coordinating an escape plan with another aircraft
5 miles away by radio is simply ludicrous.* Remember when contests
were fully manned and there was no Flarm or GPS?* I'm not against
either, as a lot of the folks here think, but I think a lot of the
fun has gone and that's the main reason I don't fly contests any
more.



So why do I keep posting?* It's out of a genuine concern that false
perceptions, unchallenged, will eventually become policy, and I
don't want any more policies.


Thank you Dan for your posts. Your opinion is important, too. I especially agree with this last paragraph.

I'll give you one example that needs to be challenged stated just a little while back. One post says"the requisite 45 seconds" and goes into some simple calculations based on 45 seconds on the display. I would like to see some actual physics calculated, but aside from that there is no basis for the 45 seconds. This is the kind of overstatement I keep talking about. It is not a lie but people are trying so hard to make their case for the outcome they desire they sometimes overstate the facts.

Pull out your iPhone and run the timer for 45seconds and you'll see it is a lot of time. There are other alternatives that may help. When a new target appears on the screen there can be simple audio alert letting you know of the new bogie. I would suggest that in this case 25 seconds of warning is plenty if collision avoidance is what you are really after. Don't take my word for it though, use some real science to come up with a real number.

The TCAS operators guide that I am looking at allows 5 secs as the outside reaction time to initiate corrective action (pitch change in the case of TCAS) resolution advisory. This is similar to the FLARM warning when a collision path is detected. I don't have complete TCAS specs readily available but perhaps other time values from TCAS could be used since their research is probably more thorough.

It makes a big difference in the final numbers if you use 45 seconds or 25 seconds. Let's make sure these numbers are based on some evidence.

XC

On Saturday, January 9, 2016 at 11:14:07 AM UTC-6, Dan Marotta wrote:
Hi Kirk,



Yes, I've towed you during at least one contest at Moriarty and I've
admired your LS-6.



Please understand that I don't "poo-poo" Flarm in my comments, I
only respond to the comments of some, which I believe are
unreasonable or downright wrong.* I always welcome logical proofs
like the math-based analysis of the pull-up (in a previous thread).



And yes, I think Flarm is a great tool for situational awareness but
I don't think that knowing a blip's ID is a requirement for safety.*
And I'm neither for nor against "stealth" mode - I don't care either
way.* The idea of coordinating an escape plan with another aircraft
5 miles away by radio is simply ludicrous.* Remember when contests
were fully manned and there was no Flarm or GPS?* I'm not against
either, as a lot of the folks here think, but I think a lot of the
fun has gone and that's the main reason I don't fly contests any
more.



So why do I keep posting?* It's out of a genuine concern that false
perceptions, unchallenged, will eventually become policy, and I
don't want any more policies.


Dan, by all means keep on posting - we need some grown-up input here now and then! But seriously, I haven't been convinced by any of the pro-stealth arguments. I would argue we should go the other way - full tracking of ALL contestants, shown in the cockpit, and let everyone share the info from all.. This may come from my sailing experience (racing Lasers), where you are immersed in the fleet, know who the hot shots are, and can see who is benefiting from wind changes, lulls, etc - all of which makes the race a much more involving event, and from my dislike of "OLC racing", which I find pretty boring (aside from not being racing in the real sense, IMO).

But then, I like the company of other gliders when I race - I must be channeling some residual Red Flag memories ;^).

Cheers,

Kirk
66

On Saturday, January 9, 2016 at 12:08:39 PM UTC-8, XC wrote:
SNIPLet's make sure these numbers are based on some evidence.

Based on evidence presented so far, we don't even have a need for a stealth, so that is an odd statement.

The 5 second TCAS has got to be a minimum, panic mode number. Also do not just consider the case of one glider meeting one glider. Consider 5 gliders meeting 5 gliders. No longer can you just turn right or pull up, doing so may well cause an accident rather than prevent one.

On Saturday, January 9, 2016 at 5:30:48 PM UTC-7, jfitch wrote:
On Saturday, January 9, 2016 at 12:08:39 PM UTC-8, XC wrote:
SNIPLet's make sure these numbers are based on some evidence.

Based on evidence presented so far, we don't even have a need for a stealth, so that is an odd statement.

The 5 second TCAS has got to be a minimum, panic mode number. Also do not just consider the case of one glider meeting one glider. Consider 5 gliders meeting 5 gliders. No longer can you just turn right or pull up, doing so may well cause an accident rather than prevent one.

TCAS is a completely different kind of system designed to work in an IFR environment. It is not GPS based. It is on board radar / transponder based. It gives specific commands to the flight crew to avoid the possible collision. Simple pull up or push over commands. The crew is expected to just do what the machine says, then tell ATC they got an RA and that's why they deviated. Visually spotting the traffic is irrelevant. Reaction time is just how quickly the crew can execute the command. No decision about what to do, just safely interrupt current process and execute.

FLARM makes absolutely no attempt to recommend how to avoid a collision. It just points out traffic and highlights potentially conflicting traffic based on the assumption both aircraft will continue to do what they have been doing. Its up to the pilot(s) to decide what to do, preferably after visually spotting the threat.