Radiation Exposure in Sailplanes

A few years back I had the opportunity to visit the Mecoplex Stand at
the Friedrichshafen Aero during which I asked about the problem of
radiation exposure and was assured that their canopy materials
absorbed both UVA and UVB to a very high degree (approx.98%). In
support of this they mailed me a copy of their catalogue
substantiating this claim. I am sure they will provide the same info
to anyone interested.

Lorry

At 06:42 12 February 2011, Lorry wrote:
A few years back I had the opportunity to visit the Mecoplex Stand at
the Friedrichshafen Aero during which I asked about the problem of
radiation exposure and was assured that their canopy materials
absorbed both UVA and UVB to a very high degree (approx.98%). In
support of this they mailed me a copy of their catalogue
substantiating this claim. I am sure they will provide the same info
to anyone interested.

Lorry

And we would want to do this because?...................

On Feb 11, 11:42*pm, Lorry wrote:
A few years back I had the opportunity to visit the Mecoplex Stand at
the Friedrichshafen Aero during which I asked about the problem of
radiation exposure and was assured that their canopy materials
absorbed both UVA and UVB to a very high degree (approx.98%). *In
support of this they mailed me a copy of their catalogue
substantiating this claim. *I am sure they will provide the same info
to anyone interested.

Lorry

It all depends on which canopy one has. My Ventus B, with original
canopy, failed a UV test miserbly with testing equipment from a local
college.

On 2/12/2011 7:29 AM, Bob wrote:
On Feb 11, 11:42 pm, wrote:
A few years back I had the opportunity to visit the Mecoplex Stand at
the Friedrichshafen Aero during which I asked about the problem of
radiation exposure and was assured that their canopy materials
absorbed both UVA and UVB to a very high degree (approx.98%). In
support of this they mailed me a copy of their catalogue
substantiating this claim. I am sure they will provide the same info
to anyone interested.

Lorry

It all depends on which canopy one has. My Ventus B, with original
canopy, failed a UV test miserbly with testing equipment from a local
college.

Exactly what was the failure? All UVA transmitted? All UVB also
transmitted? I'm very curious, because my poking around the Internet
indicates finding plastic that will transmit UVB usually involves paying
quite a bit extra for plastic with that ability.

--
Eric Greenwell - Washington State, USA (change ".netto" to ".us" to
email me)
- "Transponders in Sailplanes - Feb/2010" also ADS-B, PCAS, Flarm
http://tinyurl.com/yb3xywl
- "A Guide to Self-launching Sailplane Operation Mar/2004" Much of what
you need to know tinyurl.com/yfs7tnz

On Feb 12, 10:35*am, Eric Greenwell wrote:
On 2/12/2011 7:29 AM, Bob wrote:

On Feb 11, 11:42 pm, *wrote:
A few years back I had the opportunity to visit the Mecoplex Stand at
the Friedrichshafen Aero during which I asked about the problem of
radiation exposure and was assured that their canopy materials
absorbed both UVA and UVB to a very high degree (approx.98%). *In
support of this they mailed me a copy of their catalogue
substantiating this claim. *I am sure they will provide the same info
to anyone interested.

Lorry

It all depends on which canopy one has. *My Ventus B, with original
canopy, failed a UV test miserbly with testing equipment from a local
college.

Exactly what was the failure? All UVA transmitted? All UVB also
transmitted? I'm very curious, because my poking around the Internet
indicates finding plastic that will transmit UVB usually involves paying
quite a bit extra for plastic with that ability.

--
Eric Greenwell - Washington State, USA (change ".netto" to ".us" to
email me)
- "Transponders in Sailplanes - Feb/2010" also ADS-B, PCAS, Flarmhttp://tinyurl.com/yb3xywl
- "A Guide to Self-launching Sailplane Operation Mar/2004" Much of what
you need to know tinyurl.com/yfs7tnz


According to the gizmos, ALL UV was getting through. I guess is
someone wants some plastic that transmits lots of UV, they should
consider purchasing old S/H canopies. Still sounds like an expensive
option to me!

On Feb 12, 9:35*am, Eric Greenwell wrote:
On 2/12/2011 7:29 AM, Bob wrote:

On Feb 11, 11:42 pm, *wrote:
A few years back I had the opportunity to visit the Mecoplex Stand at
the Friedrichshafen Aero during which I asked about the problem of
radiation exposure and was assured that their canopy materials
absorbed both UVA and UVB to a very high degree (approx.98%). *In
support of this they mailed me a copy of their catalogue
substantiating this claim. *I am sure they will provide the same info
to anyone interested.

Lorry

It all depends on which canopy one has. *My Ventus B, with original
canopy, failed a UV test miserbly with testing equipment from a local
college.

Exactly what was the failure? All UVA transmitted? All UVB also
transmitted? I'm very curious, because my poking around the Internet
indicates finding plastic that will transmit UVB usually involves paying
quite a bit extra for plastic with that ability.

--
Eric Greenwell - Washington State, USA (change ".netto" to ".us" to
email me)
- "Transponders in Sailplanes - Feb/2010" also ADS-B, PCAS, Flarmhttp://tinyurl.com/yb3xywl
- "A Guide to Self-launching Sailplane Operation Mar/2004" Much of what
you need to know tinyurl.com/yfs7tnz

I got an amazing sun tan under that old ASW19 canopy. But nothing of
the sort with my DG800.
Anecdotal evidence may be indicating the canopy material of the 80's
and earlier simply let this radiation through?

On 2/13/2011 8:41 AM, db_sonic wrote:

I got an amazing sun tan under that old ASW19 canopy. But nothing of
the sort with my DG800.
Anecdotal evidence may be indicating the canopy material of the 80's
and earlier simply let this radiation through?

Anecdotal evidence can be the best kind sometimes...it's from the real world!

I remember in 1972 or 1973 Wil Schuemann coming into the office one Monday
looking like a negative raccoon: pale around the eyes with thin pale stripes
from eyeball corners to his ears, and considerably redder everywhere else on
his face. He'd gotten that way soaring his ASW-12 (in MD, but I don't remember
whether in wave) wearing glass sunglasses and the usual goofy hat.

My subsequent under-canopy experience mostly in the intermountain west has
never replicated his. If it happens it must be possible...

Regards,
Bob W.

On 2/13/2011 8:41 AM, Bob Whelan wrote:
On 2/13/2011 8:41 AM, db_sonic wrote:

I got an amazing sun tan under that old ASW19 canopy. But nothing of
the sort with my DG800.
Anecdotal evidence may be indicating the canopy material of the 80's
and earlier simply let this radiation through?

Here's some more anecdotal information: I put 3000 hours on sailplanes
built between 1969 and 1984, and did not get sunburned doing it.


Anecdotal evidence can be the best kind sometimes...it's from the real
world!

Only if you assume it's reported accurately and completely, which it
rarely is - not even mine.

I remember in 1972 or 1973 Wil Schuemann coming into the office one
Monday looking like a negative raccoon: pale around the eyes with thin
pale stripes from eyeball corners to his ears, and considerably redder
everywhere else on his face. He'd gotten that way soaring his ASW-12 (in
MD, but I don't remember whether in wave) wearing glass sunglasses and
the usual goofy hat.

How long was he in the sun before and after the flight? An hour rigging
the glider, and an hour waiting in the line for a tow, can be ten times
the exposure you get under a canopy during a 5 hour flight.

While there might seem to be a pattern of old canopies passing UV and
new ones don't, I'm skeptical until I read a report, with transmission
vs wavelength charts, of measurements on a number of old and new
canopies; alternatively, a report from the manufacturer of canopies back
then that the plastic used did transmit more UVB and a chart showing it.

--
Eric Greenwell - Washington State, USA (change ".netto" to ".us" to
email me)

I've posted this before and hope I'm not boring everyone.

Using an excellent and expensive Crawford UV meter and testing a whole
line-up of gliders one day there was a distinct pattern of older
gliders passing UV and newer gliders not. Eric, one of these days
I'll be out at EPH the same time as you are and we can do some
research on the line-up out there, but we won't get wavelength charts

My sense of this issue is that higher quality plastics have more
chemicals in them to protect the plastic itself from UV damage and
that it is protecting us as an unintended consequence. Most plastics
used in the lighting industry are very good UV filters, for example
the lenses on under cabinet fluorescent fixtures usually are very good
even on the cheapest fixtures. On the other hand there is a very
nice, small German under cabinet fluorescent (Hera) that I used to
light part of a rare book collection and ended up having to add UV
film. UV film is cheap so it was no big deal.


Brian

On Feb 13, 8:41*am, Bob Whelan wrote:
On 2/13/2011 8:41 AM, db_sonic wrote:

Anecdotal evidence can be the best kind sometimes...it's from the real world!

I'd distinguish anecdotal from empirical evidence. The latter implies
some sort of controlled experiment where the causes, effects and
exogenous variables can be measured and related, the former doesn't
and therefore is often suspect - sometimes to a very great degree.

The Wil Schuemann story falls into the anecdotal category - and it's
suspect because no one measured how much time he spent in the sun
while not under the ASW-12's canopy.

I'd be more inclined to trust experimental UV transmissivity tests on
real canopies.

9B