Canopy tinting

On Monday, April 20, 2020 at 10:50:12 AM UTC-4, Tim Taylor wrote:
Even the lighter grey and blue tints are too dark and can cause significant heat build up. I tried some at Hobbs a few years ago because my canopy is clear. Took it off right away. If you search the Soaring Archives, I believe Guy Byars wrote and article 20 years or so ago about using an orange tint to help block UV and heat.

Indeed I did write such an article. I had hoped it had been forgotten.

Applying adhesive films to a Plexiglas canopy is a bad idea. It will ruin the canopy. The films won't stretch enough for the required contours. I got around this by taping strips of a special UV film to the canopy. It worked OK for experimentation, but once that was done I removed it. No matter how carefully you apply them, they will ALWAYS wrinkle and produce distorted reflections. Also dirt and bugs will find a way to get in-between them forcing a reapplication.

I did further experiments by putting films on flat pieces of Plexiglas, like for sun shade panels in power planes. They went on great, and looked great for a few days, then they always developed bubbles and blisters. That was due to the Plexiglas being slightly porous and also venting gas over time.

The spray on products will also ruin your canopy. The products I tested were made for glass and immediately rendered my test Plexiglas samples completely opaque.

You have to ask the bigger question about exactly "WHY" you want to do this.. What problem are you looking to solve? Temperature? UV exposure? I have found the best solution for both these issues is to leave the canopy alone and wear protective clothing. Long sleeves, gloves, hats with face covers... etc.

Guy Byars

On Monday, April 20, 2020 at 1:39:18 PM UTC-4, wrote:
On Monday, April 20, 2020 at 10:50:12 AM UTC-4, Tim Taylor wrote:
Even the lighter grey and blue tints are too dark and can cause significant heat build up. I tried some at Hobbs a few years ago because my canopy is clear. Took it off right away. If you search the Soaring Archives, I believe Guy Byars wrote and article 20 years or so ago about using an orange tint to help block UV and heat.

Indeed I did write such an article. I had hoped it had been forgotten.

Applying adhesive films to a Plexiglas canopy is a bad idea. It will ruin the canopy. The films won't stretch enough for the required contours. I got around this by taping strips of a special UV film to the canopy. It worked OK for experimentation, but once that was done I removed it. No matter how carefully you apply them, they will ALWAYS wrinkle and produce distorted reflections. Also dirt and bugs will find a way to get in-between them forcing a reapplication.

I did further experiments by putting films on flat pieces of Plexiglas, like for sun shade panels in power planes. They went on great, and looked great for a few days, then they always developed bubbles and blisters. That was due to the Plexiglas being slightly porous and also venting gas over time.

The spray on products will also ruin your canopy. The products I tested were made for glass and immediately rendered my test Plexiglas samples completely opaque.

You have to ask the bigger question about exactly "WHY" you want to do this. What problem are you looking to solve? Temperature? UV exposure? I have found the best solution for both these issues is to leave the canopy alone and wear protective clothing. Long sleeves, gloves, hats with face covers... etc.

Guy Byars

That cleared the questions I had. Thanks for your reply.

On Monday, April 20, 2020 at 11:07:19 AM UTC-5, wrote:
When I replaced my ventus canopy I enquired about two things UV blockage and tint. They, the factory, answered both tinted and untinted are formulated to block 95% UV just a little less 99% that is glass. So I opted for the untinted for the reasons stated in previous posts.

CH

My Phoenix Motorglider has a tinted canopy. This has a very significant advantage in that it makes it easier to read my iPad and glass cockpit instruments. I have no experience applying tinting to an existing canopy, but if you are getting a new canopy, I would definitely recommend tinting.

On Monday, April 20, 2020 at 2:26:27 AM UTC-7, wrote:
On Monday, April 20, 2020 at 5:49:26 AM UTC+2, Paul wrote:
Question: Is it possible to tint a canopy like a car, for example, using automotive window tinting material? I know some canopies are tinted a bluish color, but what about a dark black tint?

Thanks,

It's poorly advertised but Mecaplex offers an IR-blocking tint which I've ordered after some hassle.
As a fraction of light blocked:
Colour / Visible / IR
Standard grey / 76% / 74%
IR blocking grey / 77% / 47%
Blue / 78% / 78%

Sunlight is about 45/55 visible/IR(?), so my napkin math suggests assuming 1000W/sqm:

(450 * 0.76) + (550 * 0.74) = 749W
(450 * 0.77) + (550 * 0.47) = 605W
- ~25% cooler than typical tinted for no loss in visibility.

I don't know what fraction of either is blocked by an untinted canopy in comparison? Approximately 0% or more?

You don't need an IR blocking tint as acrylic blocks UV all by itself:

https://www.gsoptics.com/transmission-curves/

Tinted glider canopies as sold on new gliders are nothing to do with increasing UV protection. They are intended to reduce IR transmission into the cockpit and make it a little cooler. That is why they are at the blue end of the colour spectrum i.e. the opposite of "blue blocker" brown sun spec lenses. Most heating in the cockpit on the ground comes from the greenhouse effect and that is only slightly reduced by tinting but my own subjective impression is that direct sun on to my person feels a little less hot through a blue tinted canopy.

On Tuesday, April 21, 2020 at 12:50:20 AM UTC-4, 2G wrote:
On Monday, April 20, 2020 at 2:26:27 AM UTC-7, wrote:
On Monday, April 20, 2020 at 5:49:26 AM UTC+2, Paul wrote:
Question: Is it possible to tint a canopy like a car, for example, using automotive window tinting material? I know some canopies are tinted a bluish color, but what about a dark black tint?

Thanks,

It's poorly advertised but Mecaplex offers an IR-blocking tint which I've ordered after some hassle.
As a fraction of light blocked:
Colour / Visible / IR
Standard grey / 76% / 74%
IR blocking grey / 77% / 47%
Blue / 78% / 78%

Sunlight is about 45/55 visible/IR(?), so my napkin math suggests assuming 1000W/sqm:

(450 * 0.76) + (550 * 0.74) = 749W
(450 * 0.77) + (550 * 0.47) = 605W
- ~25% cooler than typical tinted for no loss in visibility.

I don't know what fraction of either is blocked by an untinted canopy in comparison? Approximately 0% or more?

You don't need an IR blocking tint as acrylic blocks UV all by itself:

Some UV, not all. Acrylic blocks UV-B, so you don't get a sunburn. But it still lets significant UV-A through, which can cause deeper skin damage. Best to cover exposed areas with opaque material.

direct sun on to my person feels a little less hot...

It would actually feel a lot less hot if those areas of your person were covered with sun protective material.

You miss my point gbfwi. I said nothing about the UV protection characteristics of canopy materials. I was stating that the reason tinted canopies are sold on gliders is not to do with additional UV filtering. For that I always wear full length UV protecting clothing, hat and sun shade gloves + factor 50 when gliding.

On Tuesday, April 21, 2020 at 6:23:20 AM UTC-4, wrote:
You miss my point gbfwi. I said nothing about the UV protection characteristics of canopy materials.

Sorry, I misunderstood when you said "acrylic blocks UV".

On Sunday, April 19, 2020 at 10:49:26 PM UTC-5, Paul wrote:
Question: Is it possible to tint a canopy like a car, for example, using automotive window tinting material? I know some canopies are tinted a bluish color, but what about a dark black tint?

Thanks,

For what it is worth, I flew an SHK with a Roy Poquette supplied dark tinted canopy for several years and didn't know sun heating under a canopy until I switched to a clear canopy in a standard cirrus. dramatic difference!
Scott