High Vis Markings

On Sat, 23 Jan 2016 05:15:08 -0800, Casey wrote:

Martin,
Dark under wing shows up better (my opinion and article I just read).
Large contest numbers or European registration numbers under side of
wing stand out well.

Well, big dark registration would certainly show up better than unlit
reflectors. That was my point: that reflectors mounted where the sun
never shines on them aren't a lot of use.

However, while large, dark registration or comp ID is readable on a
glider that is within a fairly narrow overhead cone and probably not a
lot more than 1000ft above you, its unlikely that they are even visible
if the glider is more than a kilometer away or 2-3000 ft higher.

IOW, I don't think the reg etc. make any difference to the visibility of
gliders that are over 1 km away and in any case a glider should be easy
to see at that distance if its above or below you.


--
martin@ | Martin Gregorie
gregorie. | Essex, UK
org |

2 Yrs ago I saw a Silent2 FES with the LED on fin. I understand AS is offering as an option too. Just wondering why manufactures are not offering LED on underside or if they actually are. Or maybe the LED on fin can been seen some from forward/below.

On Saturday, January 23, 2016 at 9:32:00 AM UTC-5, Martin Gregorie wrote:
On Sat, 23 Jan 2016 05:15:08 -0800, Casey wrote:

Martin,
Dark under wing shows up better (my opinion and article I just read).
Large contest numbers or European registration numbers under side of
wing stand out well.

Well, big dark registration would certainly show up better than unlit
reflectors. That was my point: that reflectors mounted where the sun
never shines on them aren't a lot of use.

However, while large, dark registration or comp ID is readable on a
glider that is within a fairly narrow overhead cone and probably not a
lot more than 1000ft above you, its unlikely that they are even visible
if the glider is more than a kilometer away or 2-3000 ft higher.

IOW, I don't think the reg etc. make any difference to the visibility of
gliders that are over 1 km away and in any case a glider should be easy
to see at that distance if its above or below you.


--
martin@ | Martin Gregorie
gregorie. | Essex, UK
org |

In my ASG-29 the LED strobe is maybe 14 inches long and is the leading edge of the vertical fin. Yes it projects forward.

On Saturday, January 23, 2016 at 9:04:20 AM UTC-8, Casey wrote:
2 Yrs ago I saw a Silent2 FES with the LED on fin. I understand AS is offering as an option too. Just wondering why manufactures are not offering LED on underside or if they actually are. Or maybe the LED on fin can been seen some from forward/below.

On Saturday, January 23, 2016 at 9:32:00 AM UTC-5, Martin Gregorie wrote:
On Sat, 23 Jan 2016 05:15:08 -0800, Casey wrote:

Martin,
Dark under wing shows up better (my opinion and article I just read).
Large contest numbers or European registration numbers under side of
wing stand out well.

Well, big dark registration would certainly show up better than unlit
reflectors. That was my point: that reflectors mounted where the sun
never shines on them aren't a lot of use.

However, while large, dark registration or comp ID is readable on a
glider that is within a fairly narrow overhead cone and probably not a
lot more than 1000ft above you, its unlikely that they are even visible
if the glider is more than a kilometer away or 2-3000 ft higher.

IOW, I don't think the reg etc. make any difference to the visibility of
gliders that are over 1 km away and in any case a glider should be easy
to see at that distance if its above or below you.


--
martin@ | Martin Gregorie
gregorie. | Essex, UK
org |

On Fri, 22 Jan 2016 06:23:34 -0800 (PST), Casey
wrote:

With all the posts regarding collision avoidance electronics, I was wondering about high vis markings.

Seems like many of us put thousands of dollars into electronics and nothing into high vis markings.

Kinda hard to believe the infinite wisdom master has not mandated it, and especially since a transposer is not required.

USAF airplanes had Day-Glo markings in the Fifties, but it went away.
IIRC they concluded it just wasn't getting results, even with all
their formation flying.

rj

The cross country model glider guys have found that the best color for visibility at distance is flat black. This applies both in the blue and under cloud. Black anti collision marking would be awesome.
Darth.

On Sunday, January 24, 2016 at 10:34:26 PM UTC+3, wrote:
The cross country model glider guys have found that the best color for visibility at distance is flat black. This applies both in the blue and under cloud. Black anti collision marking would be awesome.

Conversely, in WW2 the British discovered that the best camo paint job for low level bombers was actually bright lights along the leading edges, to make them as bright as the sky. Even white paint is much darker than the background.

Well, certain sunglasses also help objects standing out. Wouldn't be cool to have a high vis paint the shows up with special sun glasses that does not show up without them. Someone could make a mint with the paint and sunglasses.

I had a hard time finding sunglasses that I like that were not too dark or polarized.

Seems to me the best is to have LEB strobe. Otherwise it would not be offered on new gliders.

On Sunday, January 24, 2016 at 6:33:11 PM UTC-5, Casey wrote:
Well, certain sunglasses also help objects standing out. Wouldn't be cool to have a high vis paint the shows up with special sun glasses that does not show up without them. Someone could make a mint with the paint and sunglasses.

I had a hard time finding sunglasses that I like that were not too dark or polarized.

Seems to me the best is to have LEB strobe. Otherwise it would not be offered on new gliders.

....or everyone be required to fly with FLARM or ADS-B connected to google glass! (with a maximum range in comp mode of course...

Sorry, i couldn't resist.

As the referenced article reminds me, there were some controlled experiments in the U.K. years back that empirically debunked the popular wisdom that Day-Glo tips and tail significantly enhanced visibility at a distance. This followed the movement in the mid to late 1970s when German gliders started arriving in the U.S. with orange/red tips and checkerboard tails. This trend seem to die out later as the evidence mounted that the high-viz paints didn't always help and, in fact, could hurt. I recall reading about experiments with mirrored coatings and black underside paints, two things that did seem to help in some circumstances. But it's dangerous to assume that what looks highly visible on the launch grid or close by in a thermal will work equally well at a distance, in particular on a collision course.

I'd argue the "big sky theory" (however one defines it) is still valid. What's undeniable is the probability that however remote, the odds of an encounter with another aircraft in that big sky are not zero and the consequences of that tiny probability are so devastating that it's worth seeking ways to reduce the risk.

I'm not current on the origins of FLARM but I seem to recall one of the drivers was the concentration of gliders along certain mountain ranges and ridgelines in the Alps, coupled with myriad cables and towers that posed a danger to low-flying gliders (I believe that was the reason for the obstruction database provided for in FLARM).

I suspect the only time we see that kind of concentrated traffic here in the U.S. is around major airports/airways/navigational features (where we either can't fly anyway or most pilots fly with heightened awareness and concern) and at large soaring contests, the size of which has diminished over the past 30 years. Nephi--which will almost certainly be oversubscribed--looks to be the exception to that.

One final not-quite-apocryphal story: back in the days of 65-glider national contests, I recall one attended by a pilot in a brightly colored Finnish glider. The pilot was thought by many to be particularly aggressive in thermals, so much so that a sighting of the "yellow PIK inbound" was often enough to prod even the most quavering, unapologetic leech to roll out on course in alarm. I don't know if yellow is the best color for visibility but against the background of Midwestern farm fields, it stood out pretty well.

Chip Bearden

On Tue, 26 Jan 2016 15:46:55 -0800 (PST),
wrote:

.... text deleted
I suspect the only time we see that kind of concentrated traffic
here in the U.S. is around major airports/airways/navigational features
(where we either can't fly anyway or most pilots fly with heightened
awareness and concern) and at large soaring contests, the size of which
has diminished over the past 30 years. Nephi--which will almost certainly
be oversubscribed--looks to be the exception to that.

.... text deleted

Unfortuantely a mid-air collision only requires 2 aircraft. Recall the
very tragic accident at Crazy Creek on Nov 28, 2009 (NTSB Docket.
WPR10FA068A and WPR10FA068B). We lost 2 good pilots.

At Texas Soaring Association this accident was one of the prime
drivers for equipping our entire club glider fleet (10), including our
Pawnee towplanes (3), with PowerFlarm when the units were first
released to the US in 2011.

Not saying Flarm would have prevented the Crazy Creek accident, but
"see and avoid" is clearly not 100% effective.

On a busy day TSA can have two towplanes and upwards of two dozen
gliders all within a few miles of the gliderport. Flarm is cheap
insurance.

Bob