Avoid head-on collision? Forward facing LED strobe?

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...l?dsId=2567554

http://www.onlinecontest.org/olc-2.0...l?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

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

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...&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...l?dsId=2567554



http://www.onlinecontest.org/olc-2.0...l?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

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.

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/...g_landing.html

http://www.aircraftspruce.com/menus/...ng_beacon.html

My favorite at the moment is http://www.aircraftspruce.com/catalo...tingBeacon.php

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.