What is the conventional wisdom on fiberglass top trailers? I've never had
any experience with one. Should I keep it this way and stay away from it by
all means? Or is it OK, really, and not much worse than Al top? How long do
they last and how much maintenance require? What are the pros and cons of
each? I'd think that metal is more durable and virtually maintenance free,
while glass may be a bit lighter. Anything else? Thanks! -- Y

Yuliy Gerchikov wrote:
> What is the conventional wisdom on fiberglass top trailers? I've never had
> any experience with one. Should I keep it this way and stay away from it by
> all means? Or is it OK, really, and not much worse than Al top? How long do
> they last and how much maintenance require? What are the pros and cons of
> each? I'd think that metal is more durable and virtually maintenance free,
> while glass may be a bit lighter. Anything else? Thanks! -- Y

My fiberglass trailer is only 29 years old so I can't comment on
durability. :-) It did get repainted about 5 years ago.
Some claim UV light can penetrate a fiberglass top and that the
accumulated irradiation of the glider will cause damage to the ship. I
used to fly at Boulder, CO where all of the trailers are parked oriented
nearly east-west exposing a long southern face to the Colorado sunshine.
Trailers occupy the same spot for years on end, and, not that I've
taken a poll, but I've never heard of any ships with damage to the top
of one wing and the bottom of the other, or one side of the fuse or fin
due to a fiberglass top.

Shawn

"Shawn" <sdotherecurry@bresnannextdotnet> wrote:
> Some claim UV light can penetrate a fiberglass top and that the
> accumulated irradiation of the glider will cause damage to the ship. I
> used to fly at Boulder, CO where all of the trailers are parked oriented
> nearly east-west exposing a long southern face to the Colorado sunshine.
> Trailers occupy the same spot for years on end, and, not that I've taken a
> poll, but I've never heard of any ships with damage to the top of one wing
> and the bottom of the other, or one side of the fuse or fin due to a
> fiberglass top.

Could it be because sun in Colorado in summer shines straight DOWN? ;)
Seriously though, can fiberglass top be painted with aluminum silver (inside
or outside) for added UV protection?

> Shawn
--
Y

Yuliy Gerchikov wrote:
> What is the conventional wisdom on fiberglass top trailers? I've never had
> any experience with one. Should I keep it this way and stay away from it by
> all means? Or is it OK, really, and not much worse than Al top? How long do
> they last and how much maintenance require? What are the pros and cons of
> each? I'd think that metal is more durable and virtually maintenance free,
> while glass may be a bit lighter.

Better check with the manufacturer - I think the aluminum Cobra trailer
top is lighter than a fiberglass top.


--
Change "netto" to "net" to email me directly

Eric Greenwell
Washington State
USA

"Eric Greenwell" > wrote in message
...
>> I'd think that metal is more durable and virtually maintenance free,
>> while glass may be a bit lighter.
>
> Better check with the manufacturer - I think the aluminum Cobra trailer
> top is lighter than a fiberglass top.

Gee, there goes the only advantage I could think of... :)

> Eric Greenwell
--
Y

In article >, Yuliy Gerchikov
> writes
>What is the conventional wisdom on fiberglass top trailers? I've never had
>any experience with one. Should I keep it this way and stay away from it by
>all means? Or is it OK, really, and not much worse than Al top? How long do
>they last and how much maintenance require? What are the pros and cons of
>each? I'd think that metal is more durable and virtually maintenance free,
>while glass may be a bit lighter. Anything else? Thanks! -- Y
>
>
I don't know what the conventional wisdom (equals what other
people think) re glassfibre top trailers is, but perhaps my experience
might be helpful.

We had a trailer which was built of G.R.P on a steel tube frame.
Not a lift top design, more of a box. Our syndicate kept our wooden
glider in this for over 20 years, it was always dry. We couldn't tow
much more than 60mph with it, behind a Volvo 245.

Ten years ago we bought a more modern sailplane in a very
convenient, all metal lift top trailer. It tows much better, no problems
even at 70. But in the UK climate, it gets very damp in there,
particularly when it suddenly gets warmer after a cold snap.

I think the advantages of the more modern trailer outweigh the
disadvantages.



--
Mike Lindsay

Yuliy Gerchikov wrote:
> What is the conventional wisdom on fiberglass top trailers? I've never had
> any experience with one. Should I keep it this way and stay away from it by
> all means? Or is it OK, really, and not much worse than Al top? How long do
> they last and how much maintenance require? What are the pros and cons of
> each? I'd think that metal is more durable and virtually maintenance free,
> while glass may be a bit lighter. Anything else? Thanks! -- Y
>
>
My trailer is a 1971 Manufacture glass fibre top, steel tube chassis with a ply
floor. It as thus far endured 35 years of the South African sun without
significant deterioration of the (phenolic resin) glass.

The steel tubes had some surface rust, which I treated two years ago, and at the
same time repainted the glass with 2K. The paint job was largely for cosmetic
reasons as a previous owner had ripped a hole in the side and repaired it with
duct tape and textured wall paint...

The part of the trailer that is disintegrating is the plywood floor.

I seriously doubt there is any meaningful penetration of UV - the gel goat and /
or paint will stop this. I for some obscure reason you have a transparent glass
top, then it would be advisable to paint or gel coat it.

For what it is worth the glider stays dry and cool in the glass trailer, and it
tows pretty well. I can't vouch for an aluminium trailer, but my trailer grosses
out at 650Kg (weighed on a bridge) with a standard cirrus, and nothing else in
it. Said Cirrus is 212Kg so the trailer is 438Kg.

Tows easily behind a 1600cc (77Kw) hatchback, as the glass is streamlined.
(Hint - trailers with sharp corners are much more affected by crosswinds)

One disadvantage of the older glider trailers is the partial hinged top. This is
clumsy to open and the supports get in the way. The newer designs with their
full pop tops are far superior.

--
Bruce Greeff
Std Cirrus #57
I'm no-T at the address above.

Comparing modern Cobra trailers the glass top is less expensive and
(subjective) looks better than the metal top. I would also expect the
glass top to be easier to repair in the event of minor damage. I have
no concern about UV penetration of the glass top. It is double
skinned.

The downside of the glass top is that the the finish does not seem to
last no matter how often it is polished and waxed. The dealer that
sold me my ship suggested it would be cheaper to repaint the top in 5
years that to have paid for the metal top. We'll see.

If buying a used trailer you should look for a problem common to both
types of top. The base of the top is a special aluminium (there I
said it) extrusion that carries the retainers for the wing spar
fittings. If the top is closed with the wing fittings not fully
forward the retainer hits the fittings and the side rail extrusions can
be badly damaged. I have seen several trailers with this problem,
including one that was delivered that way from the (sailplane) factory.

Andy (GY)

Comparing modern Cobra trailers the glass top is less expensive and
(subjective) looks better than the metal top. I would also expect the
glass top to be easier to repair in the event of minor damage. I have
no concern about UV penetration of the glass top. It is double
skinned.

The downside of the glass top is that the the finish does not seem to
last no matter how often it is polished and waxed. The dealer that
sold me my ship suggested it would be cheaper to repaint the top in 5
years that to have paid for the metal top. We'll see.

If buying a used trailer you should look for a problem common to both
types of top. The base of the top is a special aluminium (there I
said it) extrusion that carries the retainers for the wing spar
fittings. If the top is closed with the wing fittings not fully
forward the retainer hits the fittings and the side rail extrusions can
be badly damaged. I have seen several trailers with this problem,
including one that was delivered that way from the (sailplane) factory.

Andy (GY)

Comparing modern Cobra trailers the glass top is less expensive and
(subjective) looks better than the metal top. I would also expect the
glass top to be easier to repair in the event of minor damage. I have
no concern about UV penetration of the glass top. It is double
skinned.

The downside of the glass top is that the the finish does not seem to
last no matter how often it is polished and waxed. The dealer that
sold me my ship suggested it would be cheaper to repaint the top in 5
years that to have paid for the metal top. We'll see.

If buying a used trailer you should look for a problem common to both
types of top. The base of the top is a special aluminium (there I
said it) extrusion that carries the retainers for the wing spar
fittings. If the top is closed with the wing fittings not fully
forward the retainer hits the fittings and the side rail extrusions can
be badly damaged. I have seen several trailers with this problem,
including one that was delivered that way from the (sailplane) factory.

Andy (GY)

Comparing modern Cobra trailers the glass top is less expensive and
(subjective) looks better than the metal top. I would also expect the
glass top to be easier to repair in the event of minor damage. I have
no concern about UV penetration of the glass top. It is double
skinned.

The downside of the glass top is that the the finish does not seem to
last no matter how often it is polished and waxed. The dealer that
sold me my ship suggested it would be cheaper to repaint the top in 5
years that to have paid for the metal top. We'll see.

If buying a used trailer you should look for a problem common to both
types of top. The base of the top is a special aluminium (there I
said it) extrusion that carries the retainers for the wing spar
fittings. If the top is closed with the wing fittings not fully
forward the retainer hits the fittings and the side rail extrusions can
be badly damaged. I have seen several trailers with this problem,
including one that was delivered that way from the (sailplane) factory.

Andy (GY)

Y,

I own two Cobra trailers -- one fiberglass topped, the other aluminum.
The fiberglass trailer is only 5 years old but is already dull and
oxydized (it spent two years in Colorado and two in Arizona). It needs
a day or two of work with a polisher and buffing compound. The aluminum
trailer is 2 years younger but still looks brand new after three years
in Arizona. Given a choice between the two, if I was ordering new, it
would be the aluminum.

-ted/2NO

Shawn wrote:
> Some claim UV light can penetrate a fiberglass top and that the
> accumulated irradiation of the glider will cause damage to the ship.
>
> Shawn
Have any of "some" ever done a transmission spectra of the material?
Fat chance. Even window glass cuts of about 400 nm.
...lew...

Yuliy Gerchikov wrote:
> What is the conventional wisdom on fiberglass top trailers? I've never had
> any experience with one. Should I keep it this way and stay away from it by
> all means? Or is it OK, really, and not much worse than Al top? How long do
> they last and how much maintenance require? What are the pros and cons of
> each? I'd think that metal is more durable and virtually maintenance free,
> while glass may be a bit lighter. Anything else? Thanks! -- Y
>
>

No UV is going to be able to penetrate the fiberglass top. This is a
myth. One plus for the fiberglass is that there are no seams and I do
know of one aluminum topped trailer which developed a leak when it
rained. Probably a bad data point, but if you have a seam, it is a
place that can leak later in life...

Comparing modern Cobra trailers the glass top is less expensive and
(subjective) looks better than the metal top. I would also expect the
glass top to be easier to repair in the event of minor damage. I have
no concern about UV penetration of the glass top. It is double
skinned.

The downside of the glass top is that the the finish does not seem to
last no matter how often it is polished and waxed. The dealer that
sold me my ship suggested it would be cheaper to repaint the top in 5
years that to have paid for the metal top. We'll see.

If buying a used trailer you should look for a problem common to both
types of top. The base of the top is a special aluminium (there I
said it) extrusion that carries the retainers for the wing spar
fittings. If the top is closed with the wing fittings not fully
forward the retainer hits the fittings and the side rail extrusions can
be badly damaged. I have seen several trailers with this problem,
including one that was delivered that way from the (sailplane) factory.

Andy (GY)

Yuliy Gerchikov wrote:
> "Shawn" wrote:
>
>>Some claim UV light can penetrate a fiberglass top and that the
>>accumulated irradiation of the glider will cause damage to the ship. I
>>used to fly at Boulder, CO where all of the trailers are parked oriented
>>nearly east-west exposing a long southern face to the Colorado sunshine.
>>Trailers occupy the same spot for years on end, and, not that I've taken a
>>poll, but I've never heard of any ships with damage to the top of one wing
>>and the bottom of the other, or one side of the fuse or fin due to a
>>fiberglass top.
>
>
> Could it be because sun in Colorado in summer shines straight DOWN? ;)

Nah, just feels that way when you haven't used enough sunscreen.
Boulder straddles the 40th parallel, the highest the sun gets at the
summer solstice, is 73.5 deg above the southern horizon, and that's the
cloudy season. All those fair weather cu's :-)

> Seriously though, can fiberglass top be painted with aluminum silver (inside
> or outside) for added UV protection?

Don't see why not, but what for?

Shawn

Having had two makes of lift top trailer - one with
a seamed aluminium top and one GRP - if I were going
to get another then it would have a one-piece metal
top with optional factory insulation - like Cobra offer.




At 18:54 08 January 2006, Gary Emerson wrote:
>Yuliy Gerchikov wrote:
>> What is the conventional wisdom on fiberglass top
>>trailers? I've never had
>> any experience with one. Should I keep it this way
>>and stay away from it by
>> all means? Or is it OK, really, and not much worse
>>than Al top? How long do
>> they last and how much maintenance require? What are
>>the pros and cons of
>> each? I'd think that metal is more durable and virtually
>>maintenance free,
>> while glass may be a bit lighter. Anything else? Thanks!
>>-- Y
>>
>>
>
>No UV is going to be able to penetrate the fiberglass
>top. This is a
>myth. One plus for the fiberglass is that there are
>no seams and I do
>know of one aluminum topped trailer which developed
>a leak when it
>rained. Probably a bad data point, but if you have
>a seam, it is a
>place that can leak later in life...
>

Lew Hartswick wrote:
> Shawn wrote:
>
>> Some claim UV light can penetrate a fiberglass top and that the
>> accumulated irradiation of the glider will cause damage to the ship.
>> Shawn
>
> Have any of "some" ever done a transmission spectra of the material?
> Fat chance. Even window glass cuts of about 400 nm.

Not that I've heard. UV measurement inside trailers has been discussed
here before too.
Why bother if after nearly forty years of glass ships in glass trailers
hasn't shown obvious damage. Lots of crazed finishes in old gliders in
metal trailers too.

Shawn

Marc Ramsey wrote:
I had yet another trailer
> with glass on steel frame, the gelcoat deteriorated, so I had it sanded
> and repainted in white automotive acrylic. Within a year or two it was
> obvious which parts of the glider were facing upwards in the trailer, as
> those parts were distinctly yellower. I've seen a glider which had
> badly crazed gelcoat just in those areas that face upward in its

Now you've done it. Ruined a perfectly good discussion with data. ;-)

Good to know, thanks.

Shawn

Lew Hartswick wrote:
> Shawn wrote:
>
>> Some claim UV light can penetrate a fiberglass top and that the
>> accumulated irradiation of the glider will cause damage to the ship.
>> Shawn
>
> Have any of "some" ever done a transmission spectra of the material?
> Fat chance. Even window glass cuts of about 400 nm.
> ...lew...

I suspect some UV gets through fiberglass cloth, it is a woven material,
after all. Not all fiberglass trailer tops are created equally. Some
are a few layers of glass supported by a steel tube frame, some are free
standing glass/foam/glass sandwiches. Some have gelcoat on the outside,
some are painted with polyurethane or acrylic. Some have dark opaque
paint on the inside, some are just left bare.

I had a trailer with a sandwich top, polyurethane on the outside, pretty
grey spackle paint on the inside. I could read a book by the light that
came through the top when I was closed up inside (the glider was also
painted with polyurethane, however, no gelcoat to damage). I had
another trailer with a sandwich top, gelcoat outside, thick dark gray
paint inside, it was totally dark inside. I had yet another trailer
with glass on steel frame, the gelcoat deteriorated, so I had it sanded
and repainted in white automotive acrylic. Within a year or two it was
obvious which parts of the glider were facing upwards in the trailer, as
those parts were distinctly yellower. I've seen a glider which had
badly crazed gelcoat just in those areas that face upward in its
fiberglass top trailer.

An aluminum top protects the glider from UV, even without paint. If I
were to roll the trailer with the glider inside, I'd rather have an
aluminum top. If I lived in a damp warm area, I'd rather have a
fiberglass sandwich top with dark paint on the inside, as there would
likely be a lot less condensation inside the trailer...

Marc

Marc Ramsey wrote:

> Lew Hartswick wrote:
>
>> Shawn wrote:
>>
>>> Some claim UV light can penetrate a fiberglass top and that the
>>> accumulated irradiation of the glider will cause damage to the ship.
>>> Shawn
>>
>>
>> Have any of "some" ever done a transmission spectra of the material?
>> Fat chance. Even window glass cuts of about 400 nm.
>> ...lew...
>
>
> I suspect some UV gets through fiberglass cloth, it is a woven material,
> after all. Not all fiberglass trailer tops are created equally. Some
> are a few layers of glass supported by a steel tube frame, some are free
> standing glass/foam/glass sandwiches. Some have gelcoat on the outside,
> some are painted with polyurethane or acrylic. Some have dark opaque
> paint on the inside, some are just left bare.
>
> I had a trailer with a sandwich top, polyurethane on the outside, pretty
> grey spackle paint on the inside. I could read a book by the light that
> came through the top when I was closed up inside (the glider was also
> painted with polyurethane, however, no gelcoat to damage).

This is also true of your canopy, but it still stops almost all the UV.
The amount of visible light that penetrates is not a good indication of
the UV shielding. I believe the resins used in composite construction do
a good job of filtering, but I don't have any data for them.

> I had
> another trailer with a sandwich top, gelcoat outside, thick dark gray
> paint inside, it was totally dark inside. I had yet another trailer
> with glass on steel frame, the gelcoat deteriorated, so I had it sanded
> and repainted in white automotive acrylic. Within a year or two it was
> obvious which parts of the glider were facing upwards in the trailer, as
> those parts were distinctly yellower. I've seen a glider which had
> badly crazed gelcoat just in those areas that face upward in its
> fiberglass top trailer.

This discoloration and crazing might also be caused the heat and
dampness in the trailer. The upper foot or so inside a trailer can be
very hot in the summer sun, much hotter than the outside air temperature.
>
> An aluminum top protects the glider from UV, even without paint. If I
> were to roll the trailer with the glider inside, I'd rather have an
> aluminum top. If I lived in a damp warm area, I'd rather have a
> fiberglass sandwich top with dark paint on the inside, as there would
> likely be a lot less condensation inside the trailer...

Also my sentiments, though I would also consider an aluminum top that I
insulated.

--
Change "netto" to "net" to email me directly

Eric Greenwell
Washington State
USA

Eric Greenwell wrote:
> Marc Ramsey wrote:
>>
>> I had a trailer with a sandwich top, polyurethane on the outside,
>> pretty grey spackle paint on the inside. I could read a book by the
>> light that came through the top when I was closed up inside (the
>> glider was also painted with polyurethane, however, no gelcoat to
>> damage).
>
> This is also true of your canopy, but it still stops almost all the UV.
> The amount of visible light that penetrates is not a good indication of
> the UV shielding. I believe the resins used in composite construction do
> a good job of filtering, but I don't have any data for them.

True, but it a trailer which admits no visible light is also likely
blocking UV, a trailer that admits visible light may (or may not) be
also passing UV.

>> I had another trailer with a sandwich top, gelcoat outside, thick
>> dark gray paint inside, it was totally dark inside. I had yet another
>> trailer with glass on steel frame, the gelcoat deteriorated, so I had
>> it sanded and repainted in white automotive acrylic. Within a year or
>> two it was obvious which parts of the glider were facing upwards in
>> the trailer, as those parts were distinctly yellower. I've seen a
>> glider which had badly crazed gelcoat just in those areas that face
>> upward in its fiberglass top trailer.
>
> This discoloration and crazing might also be caused the heat and
> dampness in the trailer. The upper foot or so inside a trailer can be
> very hot in the summer sun, much hotter than the outside air temperature.

Except one could also make out the shadows of the wing saddles, etc.,
which is why we concluded it was UV damage.

>>
>> An aluminum top protects the glider from UV, even without paint. If I
>> were to roll the trailer with the glider inside, I'd rather have an
>> aluminum top. If I lived in a damp warm area, I'd rather have a
>> fiberglass sandwich top with dark paint on the inside, as there would
>> likely be a lot less condensation inside the trailer...
>
>
> Also my sentiments, though I would also consider an aluminum top that I
> insulated.

I wasn't offered that option with the last trailer I bought, but it
sounds like a good one...

Marc

Marc Ramsey wrote:

>>> I had another trailer with a sandwich top, gelcoat outside, thick
>>> dark gray paint inside, it was totally dark inside. I had yet
>>> another trailer with glass on steel frame, the gelcoat deteriorated,
>>> so I had it sanded and repainted in white automotive acrylic. Within
>>> a year or two it was obvious which parts of the glider were facing
>>> upwards in the trailer, as those parts were distinctly yellower.
>>> I've seen a glider which had badly crazed gelcoat just in those areas
>>> that face upward in its fiberglass top trailer.
>>
>>
>> This discoloration and crazing might also be caused the heat and
>> dampness in the trailer. The upper foot or so inside a trailer can be
>> very hot in the summer sun, much hotter than the outside air temperature.
>
>
> Except one could also make out the shadows of the wing saddles, etc.,
> which is why we concluded it was UV damage.

What glider was this? Discoloration from two years exposure indicates a
really poor quality gel coat. The exposure during flying must have
caused considerable yellowing, too.

--
Change "netto" to "net" to email me directly

Eric Greenwell
Washington State
USA

Eric Greenwell wrote:
> Marc Ramsey wrote:
>> Except one could also make out the shadows of the wing saddles, etc.,
>> which is why we concluded it was UV damage.
>
>
> What glider was this? Discoloration from two years exposure indicates a
> really poor quality gel coat. The exposure during flying must have
> caused considerable yellowing, too.

A DG-101 (now owned by a friend). Actually, the gel coat has stood up
remarkably well, with no obvious crazing 20 years after it was built,
but the different shades of yellowing were visible under shop lights...

Marc

Comparing modern Cobra trailers the glass top is less expensive and
(subjective) looks better than the metal top. I would also expect the
glass top to be easier to repair in the event of minor damage. I have
no concern about UV penetration of the glass top. It is double
skinned.

The downside of the glass top is that the the finish does not seem to
last no matter how often it is polished and waxed. The dealer that
sold me my ship suggested it would be cheaper to repaint the top in 5
years that to have paid for the metal top. We'll see.

If buying a used trailer you should look for a problem common to both
types of top. The base of the top is a special aluminium (there I
said it) extrusion that carries the retainers for the wing spar
fittings. If the top is closed with the wing fittings not fully
forward the retainer hits the fittings and the side rail extrusions can
be badly damaged. I have seen several trailers with this problem,
including one that was delivered that way from the (sailplane) factory.

Andy (GY)

UV transmission, through the laminate of a fiberglass trailer top, is
not an issue in regard to degrading the finish of a glider stored
inside. The titanium dioxide pigment in the exterior white gel coat of
the trailer top absorbs most of the energetic UV bandwith. The
remaining longer wavelength radiation is dispersed within the laminate
matrix.

The affects of the UV bandwith are:

UV-A
- Wavelength - 400 - 315 nm
- Has a slight affect on polymers.
- Transmits through window glass
- Does not transmit through white gel coat (TiO2)

UV-B
- Wavelength - 315 - 280 nm
- Highly energetic - degrades polymers
- Filtered out by window glass

UV-C
- Wavelength - <280 nm
- The most energetic band
- Filtered out by atmosphere

So don't lose any sleep over this speculative issue. However, keeping
the trailer cool and well ventilated is worth the effort.

Bob




Marc Ramsey wrote:
> Eric Greenwell wrote:
> > Marc Ramsey wrote:
> >> Except one could also make out the shadows of the wing saddles, etc.,
> >> which is why we concluded it was UV damage.
> >
> >
> > What glider was this? Discoloration from two years exposure indicates a
> > really poor quality gel coat. The exposure during flying must have
> > caused considerable yellowing, too.
>
> A DG-101 (now owned by a friend). Actually, the gel coat has stood up
> remarkably well, with no obvious crazing 20 years after it was built,
> but the different shades of yellowing were visible under shop lights...
>
> Marc

Seems like the answer might depend on the particulars
of the trailer. My 3-year-old Cobra has a glass top
that is black on the inside and zero visible light
gets through.

I bought it because I though it was more attractive.
I also was paranoid about leaks opening up on the
seams as it accumulated open/close cycles and road
miles - not that I have any evidence of that actually
happening.

9B

Andy Blackburn wrote:
> Seems like the answer might depend on the particulars
> of the trailer. My 3-year-old Cobra has a glass top
> that is black on the inside and zero visible light
> gets through.
>
> I bought it because I though it was more attractive.
> I also was paranoid about leaks opening up on the
> seams as it accumulated open/close cycles and road
> miles - not that I have any evidence of that actually
> happening.

After a 100,000 miles on my Cobra trailer, including a trip to Alaska,
and thousands of open/close cycles, the seams are still in perfect
condition. The newer trailers have about one-half the amount of seam
that my 10 year old trailer does, because they redesigned the front end
in a lovely way a few years ago, and now (in my opinion) it looks just
as nice as the fiberglass top.

--
Change "netto" to "net" to email me directly

Eric Greenwell
Washington State
USA

> What is the conventional wisdom on fiberglass top trailers?

Thanks for all the responses. Some of the thoughts mentioned here did not
occur to me before. -- Y

My all glass trailer (LAK T-5) is in it's 5th year of Arizona and
California sunshine with the only obvious degradation being the
fenders, which are faded and show a significant amount of deep surface
chaulking and the vinyl stick-ons which are starting to peel. The
inside is painted and the top doesn't seem to transmit visible light.
I gave it the WX treatment a few years ago, but haven't repeated it.
The tires showed sidewall checking after 3 years sufficient that they
had to be replaced.

Looking at the row of trailers where I fly, I'd have to say that the
older aluminum ones seem to age better than the glass, though. My
semitrailer was reskinned with aluminum with a baked-on finish which
has lasted 12 years with no apparent flaws other than dents and
scratches.

Ray Warshaw