I've read the posts on Progressive lenses and Bi / Tri focal lenses. And I
have both.
I need glasses for distant vision correction and have since my early teen
years. For years I flew in the USAF with prescribed contact lenses, or
regular single prescription lenses to correct for distant vision and the
younger eyes can adjust just fine for up close work.
But we age, and now I have to correct for near vision.

The eyes are too old to make that forced correction on their own and can no
longer adjust from the distant to near with my "distant" corrective lenses..
For most of my work, I wear the contacts and keep reading glasses handy for
computer and reading. Now the time has come that I cannot read a VFR chart
or a standard sized approach chart without reading glass assistance if I
have my contacts on.

I know many pilots that have fine distant vision, but use the half high
reading glasses in the cockpit.

I have used bifocals and find them workable, I am able to read the glass
cockpit panels with no problems at the intermediate range.
I have progressives, I have found from driving a car with the progressive
lenses that the periphery vision is blurred.. not as clear as looking out
the sides of my bifocal lenses. This gives me concern that if flying with my
progressive lenses that distant objects (aircraft) in the periphery will not
be clear and in focus and could easily be missed. I find that I have to look
directly at what I want to see and then adjust my view vertically with the
progressive to find the clearest picture. Not what I want to be dealing with
while flying.

A fellow pilot prefers the bi focal, with the line, he knows which part of
the lenses he is using to see out the window, and to see his instrument
panel. His glasses are adjusted, so that at normal sitting position, the
line of his bifocal is right at the line of the glare shield.

B


"Kirk Ellis" wrote in message
...

Before I ask my question thought I'd throw out a few words on my
background. After nearly a lifetime of pent up desire to fly I finally
got my PPL in 1998 at the young old age of 45. Last week I just turned
55 and unfortunately in the last ten years I have been able to log
only about 140 hours total. I have not been able to afford to fly as
much as I'd like. But that's finally beginning to change and I am
getting ready to transition from the Archer III which I last flew
more than 15 months ago to a DA40 with the G1000. Admittedly I've got
some catchin' up to do.

Now to the real reason of the post. For the last 5 years I have been
good with distant and intermediate vision albeit I have had a
restriction to carry glasses for up close reading. But these last 5
years have seen a slight decline in my distant vision as well as the
intermediate due to both presbyopia and astigmatism. Now I need
correction for all three vision distances, close up, intermediate and
infinity.

I have been to an optometrist who speciallizes in vision correction
for pilots and he has suggested progressive lenses to handle all 3
vision tasks. However, what he is prescribing is contrary to the AOA
information I see online that warn pilots to NOT use progressives for
flying due to distortion affects. I understand about the distortion
because I have been using progressives for over a year for other
tasks.

I asked about bifocals, but the eye doc said that's not a good thing
because of glare coming off the separation line and yet the AOA
recommends bi-focals and even tri-focals as the preferred solution for
pilots. I hear from some people that tri-focals are very annoying and
bifocals work better.

But how do you resolve the need for 3 focal distance with only
bifocals?

What I found interesting in the 3rd class vision requirements is that
if your far sight is not at least 20/40 you HAVE to wear glasses. If
your near sight (16 inches) is not at least 20/40 you just have to
carry the glasses with you. But there is no requirement for the
intermediate vision at around 30' - 32" which is right where the glass
panels sit in the DA40.

Seems that with glass cockpits becoming the norm the intermediate
distance is much more important. I still don't completely undersand
why the intermediate with a third class did not have any restrictions.
I assume they thought the hands on the standard analog instruments
where easy enough to see.

But the glass displays have so much digital information on them, that
it's not so easy for me to see the smaller print in focus without some
correction. I will need 3 way correction, but I am not all that
enamored of using trifocals. I think I can live with Bi-focals unless
the glare, as my doc mentioned, is a real problem. But they would have
to be set for intermedaite and distance to make sense to me in a glass
cockpit. However, what about the times you need to focus at the 16"
distance to read sectionals and charts? Perhaps an extra set of
bifocasl that has distance and near and you just switch.

It doesn't seem there is any optimal solution to this delimma and
those 2 pair is the only way I can figure to solve the problem. It's
just double the money and I am still concerned about the glare aspect
of bifocals the doc mentioned.

So what do other pilots opt for in vision correction in this glass
cockpit era?

Kirk



Kirk
PPL-ASEL