Avoid head-on collision? Forward facing LED strobe?

[son_of_flubber]

So how many of us have flown along close to cloudbase under a cloud street, and suddenly seen another glider pass us on the opposite heading?

It's obviously hard to see a glider that is coming straight at you.

So what about a narrow beam LED strobe aligned with the glide path vector... would the other glider see it? Would it be legal? Could you shine it through the canopy with a baffle to block internal reflections?

Has anyone done this?

I once saw another glider coming towards me on a ridge with wing tip strobes. It really got my attention and in plenty of time. So I kinda think that this would work.

[Tom Claffey]

LED strobe may be a good idea.
FLARM is good at the head on case.
Tom



At 00:14 25 July 2012, son_of_flubber wrote:
>So how many of us have flown along close to cloudbase under a cloud
street,
>and suddenly seen another glider pass us on the opposite heading?
>
>It's obviously hard to see a glider that is coming straight at you.
>
>So what about a narrow beam LED strobe aligned with the glide path
>vector... would the other glider see it? Would it be legal? Could you
>shine it through the canopy with a baffle to block internal reflections?
>
>Has anyone done this?
>
>I once saw another glider coming towards me on a ridge with wing tip
>strobes. It really got my attention and in plenty of time. So I kinda
>think that this would work.
>

[Eric Greenwell[_4_]]

On 7/24/2012 8:55 PM, Tom Claffey wrote:
> LED strobe may be a good idea.
> FLARM is good at the head on case.
> Tom

It's my understanding that head-on collisions are very small part of the
mid-air collisions; if so, the narrow beam strobe won't make much
difference. Flarm finds the gliders coming from all sides, the ones you
can't see before they hit you.

--
Eric Greenwell - Washington State, USA (change ".netto" to ".us" to
email me)
- "Transponders in Sailplanes - Feb/2010" also ADS-B, PCAS, Flarm
http://tinyurl.com/yb3xywl
- "A Guide to Self-launching Sailplane Operation Mar/2004" Much of what
you need to know tinyurl.com/yfs7tnz

[Kimmo Hytoenen]

FLARM tells you that there is another glider. It does not really
tell you where it is - you need to look and find it. Week ago I got
FLARM warning, without seeing the another plane.

LED strobe is not a bad idea. Compared to FLARM the cost is
very small, and installation easy. If you have LED strobe, all
other planes will see you, not only those with FLARM.

At 04:18 25 July 2012, Eric Greenwell wrote:
>On 7/24/2012 8:55 PM, Tom Claffey wrote:
>> LED strobe may be a good idea.
>> FLARM is good at the head on case.
>> Tom
>
>It's my understanding that head-on collisions are very small
part of the
>mid-air collisions; if so, the narrow beam strobe won't make
much
>difference. Flarm finds the gliders coming from all sides, the
ones you
>can't see before they hit you.
>
>--
>Eric Greenwell - Washington State, USA (change ".netto" to
".us" to
>email me)
>- "Transponders in Sailplanes - Feb/2010" also ADS-B, PCAS,
Flarm
>http://tinyurl.com/yb3xywl
>- "A Guide to Self-launching Sailplane Operation Mar/2004"
Much of what
>you need to know tinyurl.com/yfs7tnz
>

[Peter Scholz[_3_]]

Am 25.07.2012 02:14, son_of_flubber wrote:
> So how many of us have flown along close to cloudbase under a cloud street, and suddenly seen another glider pass us on the opposite heading?
>
> It's obviously hard to see a glider that is coming straight at you.
>
> So what about a narrow beam LED strobe aligned with the glide path vector... would the other glider see it? Would it be legal? Could you shine it through the canopy with a baffle to block internal reflections?
>
> Has anyone done this?
>
> I once saw another glider coming towards me on a ridge with wing tip strobes. It really got my attention and in plenty of time. So I kinda think that this would work.
>

Good idea, several solutions exist, partly professional, partly home
made. A few links:

http://www.youtube.com/watch?feature=player_profilepage&v=VRkcJjKEdKE

A solution like this can be integrated into the fin (done at
Schleicher), the additional price will be around 1200 EURO. One glider
at our airport is equipped with this, visibility is excellent.
------------------

http://www.irl-shop.de/advanced_search_result.php?keywords=gliderflash&osCsid=f2e27da50a0dc092d879688752de7f4f&x=15&y=5

This is much cheaper, and can be attached quite easily to any glider.
-------------------------

http://forum.segelflug.de/attachment.php?attachmentid=847&stc=1&thumb=1&d=1340716667

There was a discussion in the segelflug.de forum some time ago, this is
a selfmade solution from Wolfgang Schmidt.
---------------------

If you run this all day in flash mode, you'll probably need an extra
battery.
--
Peter Scholz
ASW24 JE

[Michael Clarke]

At 08:14 25 July 2012, Kimmo Hytoenen wrote:
>FLARM tells you that there is another glider. It does not really
>tell you where it is - you need to look and find it. Week ago I got
>FLARM warning, without seeing the another plane.
>
Kimmo,

It does if you have the right equipment and set it up properly. LX8000 /
9000 with voice shows you and tells you where the other glider is.

Link your Flarm to any navigation display, for example LK8000, you can
maintain awareness of other gliders and will have a vey good idea where to
look if a glider triggers a warning. This works very much better than the
standard Flarm display, and IMO better than the various Flarm analogue
displays (though I have one fitted as belt and braces).

Mike

[Kimmo Hytoenen]

At 10:11 25 July 2012, Michael Clarke wrote:
>At 08:14 25 July 2012, Kimmo Hytoenen wrote:
>>FLARM tells you that there is another glider. It does not
really
>>tell you where it is - you need to look and find it. Week ago I
got
>>FLARM warning, without seeing the another plane.
>>
>Kimmo,
>
>It does if you have the right equipment and set it up properly.
LX8000 /
>9000 with voice shows you and tells you where the other glider
is.
>
>Link your Flarm to any navigation display, for example LK8000,
you can
>maintain awareness of other gliders and will have a vey good
idea where to
>look if a glider triggers a warning. This works very much better
than the
>standard Flarm display, and IMO better than the various Flarm
analogue
>displays (though I have one fitted as belt and braces).
>
>Mike
>
>

I agree Mike. Therefore I was involved in development of
Soartronic devices, to make FLARM / PDA connections easy &
low cost. Voice warning might be a good idea, but transferring
information takes time?
FLARM systems seem to have blind points. I would like to have a
system, that helps maintaining awareness of nearby planes,
even when FLARM signal is temporally lost. LK8000 seems to
have some fresh ideas.

[Kimmo Hytoenen]

At 10:11 25 July 2012, Michael Clarke wrote:
>At 08:14 25 July 2012, Kimmo Hytoenen wrote:
>>FLARM tells you that there is another glider. It does not
really
>>tell you where it is - you need to look and find it. Week ago I
got
>>FLARM warning, without seeing the another plane.
>>
>Kimmo,
>
>It does if you have the right equipment and set it up properly.
LX8000 /
>9000 with voice shows you and tells you where the other glider
is.
>
>Link your Flarm to any navigation display, for example LK8000,
you can
>maintain awareness of other gliders and will have a vey good
idea where to
>look if a glider triggers a warning. This works very much better
than the
>standard Flarm display, and IMO better than the various Flarm
analogue
>displays (though I have one fitted as belt and braces).
>
>Mike
>
>

I agree Mike. Therefore I was involved in development of
Soartronic devices, to make FLARM / PDA connections easy &
low cost. Voice warning might be a good idea, but transferring
information takes time?
FLARM systems seem to have blind points. I would like to have a
system, that helps maintaining awareness of nearby planes,
even when FLARM signal is temporally lost. LK8000 seems to
have some fresh ideas.

[son_of_flubber]

On Wednesday, July 25, 2012 12:18:02 AM UTC-4, Eric Greenwell wrote:
>
> It's my understanding that head-on collisions are very small part of the
> mid-air collisions;

If you aggregate all pilots and all collisions, that's true.

As a rule, I avoid gaggles and crowded landing patterns. But I share the short local ridge and the cloud streets near the airport and I've had several head-on fly-bys.

Universal PowerFlarm is a much better solution.

[Tom Claffey]

At 11:28 25 July 2012, Kimmo Hytoenen wrote:
>At 10:11 25 July 2012, Michael Clarke wrote:
>>At 08:14 25 July 2012, Kimmo Hytoenen wrote:
>>>FLARM tells you that there is another glider. It does not
>really
>>>tell you where it is - you need to look and find it. Week ago I
>got
>>>FLARM warning, without seeing the another plane.
>>>
>>Kimmo,
>>
>>It does if you have the right equipment and set it up properly.
>LX8000 /
>>9000 with voice shows you and tells you where the other glider
>is.
>>
>>Link your Flarm to any navigation display, for example LK8000,
>you can
>>maintain awareness of other gliders and will have a vey good
>idea where to
>>look if a glider triggers a warning. This works very much better
>than the
>>standard Flarm display, and IMO better than the various Flarm
>analogue
>>displays (though I have one fitted as belt and braces).
>>
>>Mike
>>
>>
>
>I agree Mike. Therefore I was involved in development of
>Soartronic devices, to make FLARM / PDA connections easy &
>low cost. Voice warning might be a good idea, but transferring
>information takes time?
>FLARM systems seem to have blind points. I would like to have a
>system, that helps maintaining awareness of nearby planes,
>even when FLARM signal is temporally lost. LK8000 seems to
>have some fresh ideas.
>


Flarm blind spots are mostly about the aerial placement: you will not see
anyone directly below or above due to signals not going through fuselage.
It works well on the head on case. With the above/below blindspot you would
have been alerted earlier as the other glider approached out of blindspot.
They are not perfect and need to be used along with good lookout. With
Flarm you get a directed lookout which is very effective.
Mandatory Flarm in comps and preferably in all gliders/tugs is a small
price to pay for the increased safety, but : YOU STILL NEED TO LOOK OUT!
Tom

[Michael Clarke]

>Flarm blind spots are mostly about the aerial placement: you will not see
>anyone directly below or above due to signals not going through fuselage.
>It works well on the head on case. With the above/below blindspot you
would
>have been alerted earlier as the other glider approached out of
blindspot.
>They are not perfect and need to be used along with good lookout. With
>Flarm you get a directed lookout which is very effective.
>Mandatory Flarm in comps and preferably in all gliders/tugs is a small
>price to pay for the increased safety, but : YOU STILL NEED TO LOOK OUT!
>Tom

It is worth running the range analysis software from the Flarm web site to
check how well your aerial is working, albeit this shows the horizontal
range. I was very pleased to find a similar tool recently on the LX Nav web
site that allows you to do this for a file from an LX8000/9000.

I am experimenting with two commercially available L shaped and T shaped
aerials that are intended to reduce vertical blind spots at the expense of
some horizontal range. So far so good, and that is just with the L aerial
mounted inverted under the glare shield.

Mike

Mike

[soartech[_2_]]

So what color LED is the best in bright day conditions? All colors are
now available.

[Michael Clarke[_2_]]

At 14:32 25 July 2012, Tom Claffey wrote:
>At 11:28 25 July 2012, Kimmo Hytoenen wrote:
>>At 10:11 25 July 2012, Michael Clarke wrote:
>>>At 08:14 25 July 2012, Kimmo Hytoenen wrote:
>>>>FLARM tells you that there is another glider. It does not
>>really
>>>>tell you where it is - you need to look and find it. Week ago I
>>got
>>>>FLARM warning, without seeing the another plane.
>>>>
>>>Kimmo,
>>>
>>>It does if you have the right equipment and set it up properly.
>>LX8000 /
>>>9000 with voice shows you and tells you where the other glider
>>is.
>>>
>>>Link your Flarm to any navigation display, for example LK8000,
>>you can
>>>maintain awareness of other gliders and will have a vey good
>>idea where to
>>>look if a glider triggers a warning. This works very much better
>>than the
>>>standard Flarm display, and IMO better than the various Flarm
>>analogue
>>>displays (though I have one fitted as belt and braces).
>>>
>>>Mike
>>>
>>>
>>
>>I agree Mike. Therefore I was involved in development of
>>Soartronic devices, to make FLARM / PDA connections easy &
>>low cost. Voice warning might be a good idea, but transferring
>>information takes time?
>>FLARM systems seem to have blind points. I would like to have a
>>system, that helps maintaining awareness of nearby planes,
>>even when FLARM signal is temporally lost. LK8000 seems to
>>have some fresh ideas.
>>
>
>
>Flarm blind spots are mostly about the aerial placement: you will not see
>anyone directly below or above due to signals not going through fuselage.
>It works well on the head on case. With the above/below blindspot you
would
>have been alerted earlier as the other glider approached out of
blindspot.
>They are not perfect and need to be used along with good lookout. With
>Flarm you get a directed lookout which is very effective.
>Mandatory Flarm in comps and preferably in all gliders/tugs is a small
>price to pay for the increased safety, but : YOU STILL NEED TO LOOK OUT!
>Tom

It is well worth running the range analysis software from the Flarm web
site to check how well your aerial is working, albeit this shows the
horizontal range. I was very pleased to find a similar tool recently on the
LX Nav web site that allows you to do this for a file from an LX8000/9000.

I am experimenting with two commercially available L shaped and T shaped
aerials that are intended to reduce vertical blind spots at the expense of
some horizontal range. So far so good, and that is just with the L aerial
mounted inverted under the glare shield.

Mike

[Vaughn]

On 7/25/2012 12:50 PM, soartech wrote:
> So what color LED is the best in bright day conditions? All colors are
> now available.
>
Why not white?

Vaughn

[Peter Scholz[_3_]]

Am 25.07.2012 10:50, Peter Scholz wrote:
> Am 25.07.2012 02:14, son_of_flubber wrote:
>> So how many of us have flown along close to cloudbase under a cloud
>> street, and suddenly seen another glider pass us on the opposite heading?
>>
>> It's obviously hard to see a glider that is coming straight at you.
>>
>> So what about a narrow beam LED strobe aligned with the glide path
>> vector... would the other glider see it? Would it be legal? Could
>> you shine it through the canopy with a baffle to block internal
>> reflections?
>>
>> Has anyone done this?
>>
>> I once saw another glider coming towards me on a ridge with wing tip
>> strobes. It really got my attention and in plenty of time. So I
>> kinda think that this would work.
>>
>
> Good idea, several solutions exist, partly professional, partly home
> made. A few links:
>
> http://www.youtube.com/watch?feature=player_profilepage&v=VRkcJjKEdKE
>
> A solution like this can be integrated into the fin (done at
> Schleicher), the additional price will be around 1200 EURO. One glider
> at our airport is equipped with this, visibility is excellent.
> ------------------
>
> http://www.irl-shop.de/advanced_search_result.php?keywords=gliderflash&osCsid=f2e27da50a0dc092d879688752de7f4f&x=15&y=5
>
>
> This is much cheaper, and can be attached quite easily to any glider.
> -------------------------
>
> http://forum.segelflug.de/attachment.php?attachmentid=847&stc=1&thumb=1&d=1340716667
>
>
> There was a discussion in the segelflug.de forum some time ago, this is
> a selfmade solution from Wolfgang Schmidt.
> ---------------------
>
> If you run this all day in flash mode, you'll probably need an extra
> battery.
> --
> Peter Scholz
> ASW24 JE

Sorry, wrong link for the third solution. Use this for a larger picture:

http://forum.segelflug.de/attachment.php?attachmentid=847&stc=1&d=1340716667

--
Peter Scholz
ASW24 JE

[[email protected]]

Not sure as to the brightest LED color, but I know that in this region (New York, USA) most police, EMS and fire departments have made it a practice to add blue lights to their warning lights as this was supposed to be more visible. If I can find research to support this I'll post it.

[Dan Marotta]

I recall during WWII, maritime patrol bombers used bright white lights on
their leading edges as camoflage so they could sneak up on U-boats without
being seen. Seems the lights broke up the silhouette.


"Vaughn" > wrote in message
...
> On 7/25/2012 12:50 PM, soartech wrote:
>> So what color LED is the best in bright day conditions? All colors are
>> now available.
>>
> Why not white?
>
> Vaughn

[Don Johnstone[_4_]]

At 23:18 25 July 2012, Dan Marotta wrote:
>I recall during WWII, maritime patrol bombers used bright white lights on

>their leading edges as camoflage so they could sneak up on U-boats without

>being seen. Seems the lights broke up the silhouette.
>
>
After a comprehensive study by the RAF it was found that the colour which
was most conspicuous in a wide variety of daylight conditions was black.
The colour which was least conspicuous was, you guessed it, white or light
grey. Strobe lights are not very effective in bright daylight conditions
and when do we do most of our flying? When the sun shines.
There are very good technical reasons why the top surface of a glider must
be white but does the underside have to be?

[Eric Greenwell[_4_]]

On 7/25/2012 1:14 AM, Kimmo Hytoenen wrote:
> FLARM tells you that there is another glider. It does not really
> tell you where it is - you need to look and find it. Week ago I got
> FLARM warning, without seeing the another plane.
>
> LED strobe is not a bad idea. Compared to FLARM the cost is
> very small, and installation easy. If you have LED strobe, all
> other planes will see you, not only those with FLARM.

Are you still talking about a single, forward facing strobe, like the
original poster? If so, a glider coming up below or behind you will not
see the strobe.

If the strobes are placed so they can be seen from all sides, it might
be more useful; however, gaggling might be very distracting! I think
someone has to try this to determine how well it works.

--
Eric Greenwell - Washington State, USA (change ".netto" to ".us" to
email me)
- "Transponders in Sailplanes - Feb/2010" also ADS-B, PCAS, Flarm
http://tinyurl.com/yb3xywl
- "A Guide to Self-launching Sailplane Operation Mar/2004" Much of what
you need to know tinyurl.com/yfs7tnz

[Bill D]

> On 7/25/2012 1:14 AM, Kimmo Hytoenen wrote:
> > FLARM tells you that there is another glider. It does not really
> > tell you where it is - you need to look and find it. Week ago I got
> > FLARM warning, without seeing the another plane.
>

The original post from Kimmo was that FLARM indicated a glider in his visual range he could not see. This is not an unusual situation for airplanes even where ATC has called out the traffic. Visual aids like lights can be very useful.

Let's imagine a further step in technology. FLARM equipped aircraft know the exact 3D position of each other. An algorithm could operate a small gimbaled device like a remote pan & tilt camera mount which could aim a bright and narrow LED beam directly at the other pilot rendering that aircraft visible.

[son_of_flubber]

On Wednesday, July 25, 2012 11:07:04 PM UTC-4, Bill D wrote:
> (if threat detected) aim a bright and narrow LED beam directly at the other pilot<

Keep it simple and cheap. If FLARM detects a threat, turn ON the bright power hungry strobe. Otherwise, turn off the high power strobe (to conserve battery power and minimize distraction.)

[Alan[_6_]]

In article > Eric Greenwell > writes:
>On 7/25/2012 1:14 AM, Kimmo Hytoenen wrote:
>> FLARM tells you that there is another glider. It does not really
>> tell you where it is - you need to look and find it. Week ago I got
>> FLARM warning, without seeing the another plane.
>>
>> LED strobe is not a bad idea. Compared to FLARM the cost is
>> very small, and installation easy. If you have LED strobe, all
>> other planes will see you, not only those with FLARM.
>
>Are you still talking about a single, forward facing strobe, like the
>original poster? If so, a glider coming up below or behind you will not
>see the strobe.
>
>If the strobes are placed so they can be seen from all sides, it might
>be more useful; however, gaggling might be very distracting! I think
>someone has to try this to determine how well it works.

From what I have seen advertized, LED 'strobe' systems have fairly low
power consumption. Putting a set on with 360 degree visibility would seem
to be a good idea.

There are lots of situations where a glider is pretty close to invisible.
Flashing strobes could help in a lot of them.

Alan

[tstock]

> After a comprehensive study by the RAF it was found that the colour which
>
> was most conspicuous in a wide variety of daylight conditions was black.
>
> The colour which was least conspicuous was, you guessed it, white or light
>
> grey. Strobe lights are not very effective in bright daylight conditions
>
> and when do we do most of our flying? When the sun shines.
>
> There are very good technical reasons why the top surface of a glider must
>
> be white but does the underside have to be?


I recall a similar study by the FAA (which I can't locate at the moment) in which they found white was the color easiest to see against blue sky. White reflects the most light back to the observer.

I would lean towards a white flashing strobe myself. This should be very easy to see.

[Ramy]

On Thursday, August 2, 2012 9:59:51 AM UTC-7, tstock wrote:
> > After a comprehensive study by the RAF it was found that the colour which
>
> >
>
> > was most conspicuous in a wide variety of daylight conditions was black..
>
> >
>
> > The colour which was least conspicuous was, you guessed it, white or light
>
> >
>
> > grey. Strobe lights are not very effective in bright daylight conditions
>
> >
>
> > and when do we do most of our flying? When the sun shines.
>
> >
>
> > There are very good technical reasons why the top surface of a glider must
>
> >
>
> > be white but does the underside have to be?
>
>
>
>
>
> I recall a similar study by the FAA (which I can't locate at the moment) in which they found white was the color easiest to see against blue sky. White reflects the most light back to the observer.
>
>
>
> I would lean towards a white flashing strobe myself. This should be very easy to see.

There are already gliders out there fitted with strobe lights in the vertical fin and wing tips, so it shouldn't be too difficult to do some tests to confirm if it is effective in daylight or not. From what I heard so far, it is not very effective, but I would like to see the results of a more comprehensive study.

Ramy

[2G]

I had two near misses flying at a place where the Big Sky theory should be working at its best, Ely, NV. One was the closest I have had outside of a contest. Anyone interested can download the IGC files at:

http://www.onlinecontest.org/olc-2.0/gliding/flightinfo.html?dsId=2567554
http://www.onlinecontest.org/olc-2.0/gliding/flightinfo.html?dsId=2567342

We were both flying near cloud base at the same altitude in opposite directions. The closing rate was 235 kt. The other pilot saw me about 3 sec (22:52:38), or about 1200 ft, before collision and turned to avoid me (I was checking my position on my map and looked up as he was passing me).

This got me to looking into high intensity LED markers. We all are aware of those used by emergency vehicles; they can be seen in bright sunlight at a long distance. I was thinking of mounting one inside the cockpit of my DG400 in front of the instrument pod. I would have to modify the flash circuitry reduce the rate (thereby reducing power consumption). One potential source is:

http://www.extremetacticaldynamics.com/

The cost is a small fraction of a FLARM, and will work with non-FLARM equipped aircraft.

Tom

[son_of_flubber]

On Wednesday, August 15, 2012 2:35:18 PM UTC-4, 2G wrote:

> We were both flying near cloud base at the same altitude in opposite directions.

This is the scenario that prompted my original post.

[son_of_flubber]

On Wednesday, August 15, 2012 2:46:13 PM UTC-4, son_of_flubber wrote:
> On Wednesday, August 15, 2012 2:35:18 PM UTC-4, 2G wrote:

> > We were both flying near cloud base at the same altitude in opposite directions.

> This is the scenario that prompted my original post.

I would add that if you're underneath a cloud then you are by definition NOT in direct sunlight and your background in many cases will be a dark cloud. Please post a followup if you install a light.

[BobD]

There's a glider competing here in Uvalde with an array of about 12 LED double-strobing blubs on the leading edge of his vertical fin. A plastic lens conforming to the leading edge's airfoil shape covered the bulbs. We saw it working the other day during a landing period in which a gust front delayed landing late. The sky's light was low (about 10 minutes before sunset) and we saw him easily before we could make out the glider. It works great! It would be very useful when thermalling under a CU in the shadows. I give it thumbs up for head-on collision avoidance.

It would be cool if you could interface it to the PowerFlarm and have it activate only when PF detected an aircraft within a mile of you. I thought this design was really nice.

[son_of_flubber]

On Wednesday, August 15, 2012 4:52:11 PM UTC-4, BobD wrote:

> It would be cool if you could interface it to the PowerFlarm and have it activate only when PF detected an aircraft within a mile of you. <

Or you could keep the blink rate low until you visually see another glider, then boost the frequency and intensity. If both gliders had this feature, it would confirm when the other glider has you in sight.

One recurrent problem with a glider approaching head on is that you cannot read the tail number to give him a heads up on the radio. I guess you could always say "Glider approaching head-on" to get his attention. What would be a good "heads-up" radio call in this situation?

[Ramy]

On Wednesday, August 15, 2012 11:35:18 AM UTC-7, 2G wrote:
> I had two near misses flying at a place where the Big Sky theory should be working at its best, Ely, NV. One was the closest I have had outside of a contest. Anyone interested can download the IGC files at:
>
>
>
> http://www.onlinecontest.org/olc-2.0/gliding/flightinfo.html?dsId=2567554
>
> http://www.onlinecontest.org/olc-2.0/gliding/flightinfo.html?dsId=2567342
>
>
>
> We were both flying near cloud base at the same altitude in opposite directions. The closing rate was 235 kt. The other pilot saw me about 3 sec (22:52:38), or about 1200 ft, before collision and turned to avoid me (I was checking my position on my map and looked up as he was passing me).
>
>
>
> This got me to looking into high intensity LED markers. We all are aware of those used by emergency vehicles; they can be seen in bright sunlight at a long distance. I was thinking of mounting one inside the cockpit of my DG400 in front of the instrument pod. I would have to modify the flash circuitry reduce the rate (thereby reducing power consumption). One potential source is:
>
>
>
> http://www.extremetacticaldynamics.com/
>
>
>
> The cost is a small fraction of a FLARM, and will work with non-FLARM equipped aircraft.
>
>
>
> Tom

The big sky theory does not apply to gliders, this is why we keep having midairs and near misses. Most of us had similar experience at least once. Reason is that gliders congregate in relatively small portion of the sky, especially when cloudstreets are presented, we are all following the same energy lines at the same altitudes, and worth, our eyes are often focused above the horizon to follow the best line.

Please continue your research and post the results. Sometime all it takes is for someone to find an easy solution which works and the rest of us will follow. I am flying for years with reflective tapes on my wingtips but still can't say for sure if it is effective or not, but it doesn't hurt...

Ramy

[Darryl Ramm]

On Wednesday, August 15, 2012 11:35:18 AM UTC-7, 2G wrote:
> I had two near misses flying at a place where the Big Sky theory should be working at its best, Ely, NV. One was the closest I have had outside of a contest. Anyone interested can download the IGC files at:
>
>
>
> http://www.onlinecontest.org/olc-2.0/gliding/flightinfo.html?dsId=2567554
>
> http://www.onlinecontest.org/olc-2.0/gliding/flightinfo.html?dsId=2567342
>
>
>
> We were both flying near cloud base at the same altitude in opposite directions. The closing rate was 235 kt. The other pilot saw me about 3 sec (22:52:38), or about 1200 ft, before collision and turned to avoid me (I was checking my position on my map and looked up as he was passing me).
>
>
>
> This got me to looking into high intensity LED markers. We all are aware of those used by emergency vehicles; they can be seen in bright sunlight at a long distance. I was thinking of mounting one inside the cockpit of my DG400 in front of the instrument pod. I would have to modify the flash circuitry reduce the rate (thereby reducing power consumption). One potential source is:
>
>
>
> http://www.extremetacticaldynamics.com/
>
>
>
> The cost is a small fraction of a FLARM, and will work with non-FLARM equipped aircraft.
>
>
>
> Tom

Firing off a high intensity strobe inside your cockpit is likely to be extremely distracting to the pilot due to all the canopy reflections. You can try with a decent size photographic flash gun to get some and see how bad it is. In my DG-303 cockpit I would often wear darker trousers and shoes to avoid canopy reflections, so I don't expect this to be a workable mounting location. But mounting LED strobes at the wingtips and pulling wires down the D tube in front of the spar should not be hard. There are already one ASH-31Mi flying in the USA with factory fitted strobe options.

http://www.youtube.com/watch?v=8sbKdSa52sw

Darryl

[2G]

Firing off a high intensity strobe inside your cockpit is likely to be extremely distracting to the pilot due to all the canopy reflections. You can try with a decent size photographic flash gun to get some and see how bad it is. In my DG-303 cockpit I would often wear darker trousers and shoes to avoid canopy reflections, so I don't expect this to be a workable mounting location. But mounting LED strobes at the wingtips and pulling wires down the D tube in front of the spar should not be hard. There are already one ASH-31Mi flying in the USA with factory fitted strobe options.

Reflections can be eliminated with a reflector that mates to the curvature of the canopy. One could mount it in the nose, but this would involve significant glass work. Another option are aircraft specific LED strobes. I would even put up with the reflections to prevent a mid-air.

Tom

[son_of_flubber]

On Wednesday, August 15, 2012 7:02:59 PM UTC-4, Darryl Ramm wrote:

> Firing off a high intensity strobe inside your cockpit is likely to be extremely distracting to the pilot due to all the canopy reflections. <

This is an obvious concern, but I expect that it all depends on how close the LED is mounted to the inside surface of the canopy and whether you have a shroud closing any gaps.

Mounting in on the vertical stabilizer must have some advantages. Perhaps wider visibility? The youtube link in an earlier post is interesting:

>>Peter Scholz wrote:

> http://www.youtube.com/watch?feature=player_profilepage&v=VRkcJjKEdKE

>A solution like this can be integrated into the fin (done at
>Schleicher), the additional price will be around 1200 EURO. One glider
>at our airport is equipped with this, visibility is excellent.




On Wednesday, August 15, 2012 7:02:59 PM UTC-4, Darryl Ramm wrote:
> On Wednesday, August 15, 2012 11:35:18 AM UTC-7, 2G wrote:
>
> > I had two near misses flying at a place where the Big Sky theory should be working at its best, Ely, NV. One was the closest I have had outside of a contest. Anyone interested can download the IGC files at:
>
> >
>
> >
>
> >
>
> > http://www.onlinecontest.org/olc-2.0/gliding/flightinfo.html?dsId=2567554
>
> >
>
> > http://www.onlinecontest.org/olc-2.0/gliding/flightinfo.html?dsId=2567342
>
> >
>
> >
>
> >
>
> > We were both flying near cloud base at the same altitude in opposite directions. The closing rate was 235 kt. The other pilot saw me about 3 sec (22:52:38), or about 1200 ft, before collision and turned to avoid me (I was checking my position on my map and looked up as he was passing me).
>
> >
>
> >
>
> >
>
> > This got me to looking into high intensity LED markers. We all are aware of those used by emergency vehicles; they can be seen in bright sunlight at a long distance. I was thinking of mounting one inside the cockpit of my DG400 in front of the instrument pod. I would have to modify the flash circuitry reduce the rate (thereby reducing power consumption). One potential source is:
>
> >
>
> >
>
> >
>
> > http://www.extremetacticaldynamics.com/
>
> >
>
> >
>
> >
>
> > The cost is a small fraction of a FLARM, and will work with non-FLARM equipped aircraft.
>
> >
>
> >
>
> >
>
> > Tom
>
>
>
> Firing off a high intensity strobe inside your cockpit is likely to be extremely distracting to the pilot due to all the canopy reflections. You can try with a decent size photographic flash gun to get some and see how bad it is. In my DG-303 cockpit I would often wear darker trousers and shoes to avoid canopy reflections, so I don't expect this to be a workable mounting location. But mounting LED strobes at the wingtips and pulling wires down the D tube in front of the spar should not be hard. There are already one ASH-31Mi flying in the USA with factory fitted strobe options.
>
>
>
> http://www.youtube.com/watch?v=8sbKdSa52sw
>
>
>
> Darryl

[bill palmer]

The reason airliners turn on their landing lights (day and night usually below 10-18K ft) is not so they can see, but so others can see them!

Some airplanes use a pulsing landing light since it better differentiates between them and the reflection off of some shiny surface. I've seen that on a number of biz-jets and smaller.

It's the same reason most airplanes have a red or white rotating or pulsing "anti-collision" light (beacon).

I'd say anything to help others see you is great. If you can only point it out front it will help with the worst situation : small profile and fastest closure rate.

I'd also suggest a little test to see from just how far away the LED light is prominent.

It's almost crazy that more gliders have not adopted some kind of anti-collision light, since we may fly in close proximity, in any combination of directions, constantly passing through a range of altitudes, and often with no radio, much more so than the powered planes do.


On Tuesday, July 24, 2012 5:14:02 PM UTC-7, son_of_flubber wrote:
> So how many of us have flown along close to cloudbase under a cloud street, and suddenly seen another glider pass us on the opposite heading?
>
>
>
> It's obviously hard to see a glider that is coming straight at you.
>
>
>
> So what about a narrow beam LED strobe aligned with the glide path vector.... would the other glider see it? Would it be legal? Could you shine it through the canopy with a baffle to block internal reflections?
>
>
>
> Has anyone done this?
>
>
>
> I once saw another glider coming towards me on a ridge with wing tip strobes. It really got my attention and in plenty of time. So I kinda think that this would work.

[son_of_flubber]

There are a lot of commercial ACL LEDs available. They use 10% of the power of xenon flash tubes and they have a better form factors. That makes them a lot more practical for gliders

http://www.aircraftspruce.com/menus/el/ledlighting_landing.html

http://www.aircraftspruce.com/menus/el/ledlighting_beacon.html

My favorite at the moment is http://www.aircraftspruce.com/catalog/elpages/electRotatingBeacon.php

[tstock]

Why not a low mW red laser? It's directional, and very bright even in daylight, but low enough power would not cause eye damage.