High Vis Markings

On Friday, January 22, 2016 at 10:13:43 AM UTC-6, son_of_flubber wrote:
On Friday, January 22, 2016 at 9:23:37 AM UTC-5,
I was wondering about high vis markings.
...the infinite wisdom master has not mandated it

High vis marking is mandated in some parts of the world (French Alps?). But it is controversial whether they help or hurt in all contexts. Some people conclude that the markings work as camouflage because they erode the edge of the plane's outline/silhouette.

There was someone in the UK that got good results with putting mirror tape on ailerons that flashed sun glint to overtaking planes when the glider was on final.

Sun glint is promising. I will someday get around to experimenting with Bird Scare Ribbon streamers on my wing tips or perhaps on the tips of my horizontal stabilizer.
http://www.amazon.com/100-Foot-2-Inc...ords=bird+tape

You might want to do some testing on how draggy those streamers would be - a simple test using a car might be instructional.

My gut feeling is that any length long enough to be useful would be pretty draggy!

Let us know.

Kirk

On Friday, January 22, 2016 at 12:19:47 PM UTC-5, kirk.stant wrote:

My gut feeling is that any length long enough to be useful would be pretty draggy!

I figure the wing tip is already very draggy. How much worse could it get? I'm thinking about 12" would work as the tape acts like a signal mirror picking up the sun glint. The wing tip turbulence means it passes through a lot of different angles.

On Friday, January 22, 2016 at 1:17:50 PM UTC-6, son_of_flubber wrote:
On Friday, January 22, 2016 at 12:19:47 PM UTC-5, kirk.stant wrote:

My gut feeling is that any length long enough to be useful would be pretty draggy!

I figure the wing tip is already very draggy. How much worse could it get? I'm thinking about 12" would work as the tape acts like a signal mirror picking up the sun glint. The wing tip turbulence means it passes through a lot of different angles.

Like I said, try it out first, you may be surprised. Think of the hardware needed to attach the ribbon, or are you going to just tape it to the trailing edge? So now you have 12 inches of tape flapping in the wind - It can get a LOT worse! Or you may have come up with the best thing since sliced bread ;^)

So please, give it a try and report back!

I have orange wingtips and rudder, and other pilots have commented on how visible they make me - especially against a white background. Wouldn't fly without them...

Kirk

Kirk

On Friday, January 22, 2016 at 3:15:58 PM UTC-5, kirk.stant wrote:
On Friday, January 22, 2016 at 1:17:50 PM UTC-6, son_of_flubber wrote:
On Friday, January 22, 2016 at 12:19:47 PM UTC-5, kirk.stant wrote:

My gut feeling is that any length long enough to be useful would be pretty draggy!

I figure the wing tip is already very draggy. How much worse could it get? I'm thinking about 12" would work as the tape acts like a signal mirror picking up the sun glint. The wing tip turbulence means it passes through a lot of different angles.

Like I said, try it out first, you may be surprised. Think of the hardware needed to attach the ribbon, or are you going to just tape it to the trailing edge? So now you have 12 inches of tape flapping in the wind - It can get a LOT worse! Or you may have come up with the best thing since sliced bread ;^)

So please, give it a try and report back!

I have orange wingtips and rudder, and other pilots have commented on how visible they make me - especially against a white background. Wouldn't fly without them...

Kirk

Kirk

Reflective tape study - Oct 2002 - at http://www.dg-flugzeugbau.de/Data/gl...uity-study.pdf

And LED light mounted on front lip of canopy: http://www.how2soar.de/index.php/led...d-rechenknecht

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).