High Vis Markings

As stated above the anti-collision markings are mandated in France, and they have been proven to work! Fluorescent orange is not a color in nature and it stands out against a snowy or cloudy background. There are called High Visability marking for a reason. There is an article somewhere on-line about the effectiveness of these markings. France has mandated Flarm now and had a significant reduction in collisions.

Take a look at the Schleicher web site, they offer a LED strobe strip in the vertical fin (it is part of leading edge so no aerodynamic penalties). With an LX ACL controller the strobe fires when there is a Flarm alert! I am surprised all manufactures do not just include this unit is the base price and not even make it optional.

The big sky theory is as valid as cold fusion.

Alisport has been offering LED strobe on fin of the Silent 2 Electro for several yrs.

On Friday, January 22, 2016 at 2:22:53 PM UTC-5, Jonathan St. Cloud wrote:
As stated above the anti-collision markings are mandated in France, and they have been proven to work! Fluorescent orange is not a color in nature and it stands out against a snowy or cloudy background. There are called High Visability marking for a reason. There is an article somewhere on-line about the effectiveness of these markings. France has mandated Flarm now and had a significant reduction in collisions.

Take a look at the Schleicher web site, they offer a LED strobe strip in the vertical fin (it is part of leading edge so no aerodynamic penalties). With an LX ACL controller the strobe fires when there is a Flarm alert! I am surprised all manufactures do not just include this unit is the base price and not even make it optional.

The big sky theory is as valid as cold fusion.

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

I searched this thread and did not see an actual study referenced, only urban legend, that bright colors not found in nature somehow act to "work as camouflage because they erode the edge of the plane's outline/silhouette". Is this not the same ilk as "we only use 10% of our brain" or "it is improper English in end a sentence in a preposition"? BTW, all three urban legends have no basis in science, fact, or English structure. If you think so, you do not have a leg to stand on. Perhaps you do not know what you speak of. What are you talking about? Just three examples of one urban legend mentioned above. Autonomous processes of the body take more than 10% of brain function alone. Military uses high visibility paint on training aircraft, because it works. If you travel Russia you will also find most Russians do not wear seatbelts because they all know someone, who knew someone that was friends with someone that was saved because they were thrown free in an auto accident. Of course no one knows anyone first hand that was so saved, but they all believe the BS legends. Hmm... I wonder why hunters wear high visibility clothing? Is it to be seen so they are not shot... no I am sure the orange would just blur they edges so it would be difficult for a center shot.

France mandated high vis markings for a reason, they saw a statistically significate difference. France mandated Flarm for the same reason, it works.

I am not a fan of the big sky theory, have had way too many close calls, from the airport environment, to the middle of nowhere, thus the only possible conclusion is the theory is bunk. Sure, most aircraft do not collide, but the theory that only works 98% of the time is not really a theorem, is it.. Then it just becomes probability, fate, vicissitudes of life, karma... Imagine if the theory of relativity only worked 98% of the time. What if the laws of physics only worked 99% of the time.

Four times in the airport environment, under tower control, I have been place directly in the path of another aircraft, and this is by trained professionals. Too many times to count out in "the Big Sky", I have only had time to flench as another aircraft streaked by, once so close I did not even see an aircraft, just a grey blur filling the entire windscreen as I heard the roar of jet engines. And this was over the roar of my own jet engine and through noise cancelling headset.

Not intending to offend anyone, just to solicit thought, not rote acceptance. Show me the beef. (by way of full disclosure, I not not eat beef).

On Wednesday, 27 January 2016 09:29:58 UTC+2, Jonathan St. Cloud wrote:
I searched this thread and did not see an actual study referenced, only urban legend, that bright colors not found in nature somehow act to "work as camouflage because they erode the edge of the plane's outline/silhouette".

The fact that this topic re-appears every couple of years and generates a lot of debate suggests that not enough scientific research has been done to validate or invalidate the argument for or against anti-collision markings.

In certain situations such as a glider against a snow covered mountain, high visibility orange DayGlo certainly does help but it may also camouflage the glider in other conditions.

The RAF held glider conspicuity trials at Bicester in June and October 2002..
It evaluated 3M Mirror Film and DayGlo markings.
The summary was "We conclude that the DayGlo patches did not improve conspicuity." while the mirror film greatly increased sighting range if sunlight was present.
Source: http://www.dg-flugzeugbau.de/Data/gl...uity-study.pdf

A German flavoured study: https://www.streckenflug.at/index.php?p=technikwarn
Summary: "The use of colour markings as an anti-collision aid is questionable. In particular when two aircraft are on a constant-bearing (collision) course, it is the size and shape of the other aircraft which is seen first, not any colour pattern. The use of colour seems obvious at short range and on the ground but this is often not the critical case in the air in a collision situation." Position reporting, pilot scan technique and strobe lights were deemed to be far more effective than colour markings.

As a glider owner who is planning to repaint his glider this year in a country that doesn't mandate anti-collision markings and doesn't experience snow fall (where I fly), I am very interested in what the best solution is.
My personal conclusion is that FLARM, mirror film and strobe lights facing all directions would be a much better solution than just DayGlo markings. Unfortunately the power requirements and drag created by multiple strobe light housings retro-fitted to a glider prevents me going this route so mirror film and FLARM is probably the best bet?

"France mandated high vis markings for a reason, they saw a statistically
significate difference. France mandated Flarm for the same reason, it
works."


FRANCE mandated hi viz marking to help see gliders in the snowy backdrop of
the alps.

They also mandated FLARM for the alps as FLARM can see round corners in the
mountains and the eye can not.


Bright colour markings do nothing. If you wish to improve visibility put
silver reflective tape on each of your control surfaces.

At 09:01 27 January 2016, Justin Craig wrote:

"France mandated high vis markings for a reason, they saw a
statisticall
significate difference. France mandated Flarm for the same
reason, i
works."


FRANCE mandated hi viz marking to help see gliders in the snowy
backdrop o
the alps.

They also mandated FLARM for the alps as FLARM can see round
corners in th
mountains and the eye can not.


Bright colour markings do nothing. If you wish to improve visibility
pu
silver reflective tape on each of your control surfaces.

The "Big Sky" theory only works if all aircraft are evenly distributed
over the airspace. The restrictions and requirements of gliding
means that they are far from evenly distributed.

High vis markings (dayglo) do work with gliders against some
backgrounds if they are above or below. In the most dangerous
area, the same level they do not work too well at all as the area is so
small that the "benefit" is cancelled out.

Silver reflective tape, or mirror tape only works in sunshine. Gliders
spent a lot of time in shade, under clouds, and again at the same
level the effect is minimal. Something that requires the sun to shine
is not likely to be too effective for most of the time in the UK.

The Royal Air Force did a study which concluded that the best
colour to provide the best chance of being seen was black, which is
why all RAF training aircraft, except the GRP ones, are painted
black. From my limited experience in seeing these aircraft in the air
they certainly seem to be more easily picked out from most
backgrounds.

It would seem that what is needed is a colouring that absorbs
visible light but reflects ultra violet and infra red. So there is the
challenge.

I'm pretty sure FLARM cannot see round Alpine corners.

Adding mirror foil to control surfaces certainly works if it's
sunny but your friendly engineer or glider manufacturer might
view adding weight to the control surfaces in a different light?
I've seen it suggested that this might affect flutter?

David Walsh

The Royal Air Force did a study which concluded that the best
colour to provide the best chance of being seen was black, which is
why all RAF training aircraft, except the GRP ones, are painted
black. From my limited experience in seeing these aircraft in the air
they certainly seem to be more easily picked out from most
backgrounds.

Canadian Air Force trainers are also painted black. Best contrast against sky, clouds, snow, and prairie. Unfortunately, not possible for most gliders, and rather warm to the touch for ground handling.