Can a polished trailer cause a fire???

[Gene]

After several years of never getting to wash or polish our trailer, I now realize that was wise and I wasn't lazy. Of course, the finish on newer ones never does shine up like a vintage one. We used to polish it, but polishing something the size of a whale was never fun.

Gene

[Antique Pedaler]

Our polished Bambi II has melted holes in 2 poli patio mats. So I make it a point out in the open to park with the curb side to the east to avoid the hot pm sun.

[StarckMad]

This seems to be a true safety hazard! Has anyone contacted NHTSA? Great business idea: anti buffing. 😏

[StarckMad]

This seems to be a true safety hazard! Has any contacted NHTSA? Great business idea tho: anti buffing!

[m.hony]

I did see an episode of CHiP's where the reflection from a large mirror being transported on a glass truck blinded the driver of another truck and caused him to crash.


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[Jaxon]

When we had our '67 Safari, I was always grateful while driving at night for the highly polished exterior... never had anyone follow too closely for too long... 😏

[FreshAir]

I ruined my Airstream doormat from the concentrated sunlight from my shiny Trade Wind.

[HowieE]

i do not question that the suns rays can be concentrated to the point of starting a fire but I can envision the optical path you describe.

buffed aluminum exterior reflected the sun through a concave curved shaped window and focused perfectly on the ground where my hose was laying...

The trailer exterior is basically convexed and thus would disperse the suns rays. Where was the concaved window with respect to the exterior of the trailer that it could converge to rays?

[OTRA15]

Thank you HowieE, as I never understood the original post's geometry either, which is why I suggested a defective hose at first.

[ArtisanAir]

When windows are closed yes the trailer is convex, in which will disperse the rays. On a 67 the windows have a curve profile also. When the windows are open (parallel to the ground) , the light is refracted through the window and out the concave side (underside or inside) of the window causing a focal point on the ground next to the trailer. The origin of the reflection was on the top curve of the trailer. By using our hand we would block portions of the trailer until the focal point diminished giving us the origin of the reflection. We then found out it only focused when the window was open.

[HowieE]

There is a difference between a window and a lens. A curved window with parallel surfaces will not bend light, by convergence or divergence. If it would you would have some very strange effects when you looked into or out of your trailer.

[InsideOut]

Originally Posted by 47WeeWind

Artisan Air:

You are on the right track. Friends of mine have melted jaggy lines across the plastic "grass blades" on their artificial turf mats during bright sunny days here in Colorado. The sun reflected from, and was focused by, the open polished interior of their curved aluminum "door-within-a-door" on 1964 and earlier Airstreams. I haven't yet seen anything ignite, but the focused sun rays certainly were hot enough to melt plastic into one long linear valley on the mat. Polish that door interior enough and you won't need a separate sun oven.

Hey! I resemble that remark Fred!!! We've not started a fire...but killed some grass, melted our patio mat (more than once... ) & fried an egg! Literally...



Shari

[ArtisanAir]

It may not be a lens but here is what I believe makes sense, information provided by livescience.com


Refraction

Refraction is the bending of light rays. Normally, light travels in a straight line, and changes direction and speed when it passes from one transparent medium to another, such as from air into glass.
In a vacuum, the speed of light, denoted as "c," is constant. However, when light encounters a transparent material, it slows down. The degree to which a material causes light to slow down is called that material's refractive index, denoted as "n." According to Physics.info, approximate values of n for common materials are:
Vacuum = 1 (by definition)
Air = 1.0003 (at standard temperature and pressure)
Water = 1.33 (at 68 degrees Fahrenheit or 20 degrees Celsius)
Soda-lime crown glass = 1.51
Sapphire = 1.77
71-percent lead flint glass = 1.89
Cubic zirconia = 2.17
Diamond = 2.42
These numbers mean that the speed of light is 1.33 times slower in water and 2.42 times slower in diamond than in a vacuum.
When light passes from a region of lower n, such as air, through a surface into a region of higher n, such as glass, the light changes direction. This means its path is closer to perpendicular, or "normal," to the surface. When the light passes from a region of higher n to the region of lower n, it bends away from the "normal" direction. This is what causes the submerged part of a spoon in a glass of water to appear to bend when you put it in water.

[ROBERT CROSS]

Can a polished trailer cause a fire???


Probably

Bob

[perryg114]

Its not refraction, it is simple reflection from a concave mirror that focuses the light.

Refraction is the bending of light through a transparent material. You have to have a difference of index of refraction between two substances like air and water or air and glass. Different wavelengths are refracted differently and that is the cause of rainbows and colors from prisms.

Perry

[ArtisanAir]

Geez this thread turned into a debate. Where is Bill Nye when you need him. Regardless the reason behind it the topic was can a trailer catch things on fire...

This is the biggest problem with this forum, everyone knows everything.... or so they think. So when they try to debunk the topic, it makes people loose interest. I thought it was a interesting, now I'm done even thinking about the over analyzed event... I may or may not be correct on how I explain it. That's not my specialty. thank you to those who could stay on topic

[OTRA15]

As threads here go, this one stayed way more "on topic" than most IMO. Healthy debate is one of the best parts of this forum. If anyone starting a thread has a preconceived notion for parameters to limit debate, it might be good to post them up-front?

And then stand aside for the razzle dazzle of healthy debate!

And thank you for clarifying the geometry of the open window. I learned something else new today.

Happy trails!

Peter

[HowieE]

Yes. All to often posts have replies based on opinion rather than science.

To address the original question "Can an Airstream Cause a Fire". That is an Airstream out in the sun. In a word NO. The scientific reasons have been stated above but have failed to dissuade some.

[Ray Eklund]

Now that ArtisanAir accepts responsibility that his trailer can damage private property and acknowledges that this is indeed fact from personal research: Are the Airstream Engineers aware of these issues and are these trailers licensed as AirToasters, without any proper certification from the National Institute of AirToaster Engineers?

Should signs be posted around this trailer to protect the public when parked?

I have heard people starting on fire from Spontaneous Combustion, as well. Would these individuals be in danger, if they owned a highly polished vintage Airstream trailer or casually walked near an AirToaster?

Does a 34' Airstream contain more hazardous surface area to reflect solar energy than a 19 foot?

Should these AirToasters be banned from buying fuel at a Service Station without providing fire protection?

Many unanswered questions.

What is the minimum liability insurance required by the National Forest Service and Bureau of Land Management in the event this fire hazard on wheels is connected to a fire, or two from AirToasting wildlife and dry grass?

[ArtisanAir]

Originally Posted by Ray Eklund

Now that ArtisanAir accepts responsibility that his trailer can damage private property and acknowledges that this is indeed fact from personal research: Are the Airstream Engineers aware of these issues and are these trailers licensed as AirToasters, without any proper certification from the National Institute of AirToaster Engineers?

Should signs be posted around this trailer to protect the public when parked?

I have heard people starting on fire from Spontaneous Combustion, as well. Would these individuals be in danger, if they owned a highly polished vintage Airstream trailer or casually walked near an AirToaster?

Does a 34' Airstream contain more hazardous surface area to reflect solar energy than a 19 foot?

Should these AirToasters be banned from buying fuel at a Service Station without providing fire protection?

Many unanswered questions.

What is the minimum liability insurance required by the National Forest Service and Bureau of Land Management in the event this fire hazard on wheels is connected to a fire, or two from AirToasting wildlife and dry grass?

You just made my day