Progressive lenses OK for pilots?

skyfish wrote:
I want to get current on my VFR Single Engine Land license but my eyes
are not what they used to be. The strength I need for good far vision
makes it so I can't read charts in the cockpit without taking them off.

I have exactly the same problem. I have progressive bifocals that
pretty much just take out the distance correction in the near vision
part.

The only problem I have is that the first pair I got had the break point
where the near/far transition occurs in an inconvenient place. You
should find an optician with a clue to set this appropriately.

I've been flying with them for a year now without problems.
My old single vision I'd have to lift up to look at the chart
(and as a matter of fact, I'd put them up on my head when in
IMC (nothing to look at in the distance anyway).

"skyfish" wrote:

I want to get current on my VFR Single Engine Land license but my eyes
are not what they used to be. The strength I need for good far vision
makes it so I can't read charts in the cockpit without taking them off.

I figured I would try a progressive lens ...

I had progressive lenses when I started flying, but I found they produced
some subtle distortions that I found bothersome. I changed to trifocals,
with the middle range adjusted for panel distance. They work fine.

--
Dan
C172RG at BFM

skyfish wrote:
I want to get current on my VFR Single Engine Land license but my eyes
are not what they used to be. The strength I need for good far vision
makes it so I can't read charts in the cockpit without taking them off.
[snip specifics about progressive lenses]

I almost flunked my last medical due to not having bifocals. I finally
went to the eye-doctor and got some, but when I mentioned I am a pilot
he told me he dosen't recommend progressive bifocals for pilots. He
cited several of the concerns you did about distortion of peripheral
vision, etc. I got normal bifocals and have been fine. They do take
some getting used to, not least of which is that I don't have to take
my glasses off to read something. It's a habit that I've been working
at breaking.

Hope that helps,
John Stevens
PP-ASEL

Instead of progressive lenses, go for normal, old style bifocal lenses. The
progressive style means there is no nasty line to be seen by your friends in
your face, but you loose an area in the lens that has no useful vision for
flying as the lens changes from near to far vision in a gradual change.

See your eye doctor to check your current script and get a set made to suit
the aircraft you like to fly, so you can see the dash and out the window
without turning your head. Measure the distance from your eyes to the dash
to allow your doc to get the distance set right for you. A good eye doc will
do a second check using his test lenses with your eyes set to this distance
rather than just calculating a standard adjustment to the main script. He
will also allow for different positions of the lens for close work and
distance work, for example for me the distance between the centre of the
lens for distance is 64 mm and for close work is 62 mm. Just due to
different angles to the subject. When fitting the new frames they can mark,
with a felt pen, the centre of your eyes on the dummy lens they put in the
display glasses so the prescription lens can be accurately placed when
making them. This method is better than just measuring "inter-ocular
distance", and a decent glasses provider will do this for you.

You want to have normal vision of the outside world and your ASI and Tacho
and so on when you want it without having to change focus with your eyes.
You want to be able to see both without thinking about it so you can easily
control your plane's speed, revs and where it is on landing.

You may want to draw a rough outline of where the dash is on your old pair
of glasses with a whiteboard marker pen which can be rubbed off later. Sit
in your plane and then walk round looking like an idiot with black lines on
your specs. I know I got few funny looks, but the end result has been worth
it. The final glasses were made to suit me and have a small area of close
correction focussed perfectly at the dash and plenty of look outside at the
real world vision.

I also have a pair of close work glasses made for computer work as a full
screen view without any distance correction. Allows me to work the computer
and read the paper easily. I tend to use these for pre-flight planning when
doing lots of map work etc..

A cheap framed second pair of glasses for the cockpit is cheap insurance for
those moments that a screw falls out......

I have the modern antireflection coating and find it helps, and also suggest
you spend the extra $5.00 per lens to have the edges polished as this
reduces the glare around the edge of your vision.

Transition tint lenses that change with the available light help me, but if
you fly a high wing plane (or other with a roof) you won't have as much UV
light that causes the tint to darken, so just like when driving the car,
they won't go to full darkness.

I changed eye docs on a pilot friend's recommendation, and the new one gives
a better script with all his fancy modern gear compared to the previous one
with his fingerprint and dust covered test lenses.

Hope this helps,
Pete

"skyfish" wrote in message
0...
I want to get current on my VFR Single Engine Land license but my eyes
are not what they used to be. The strength I need for good far vision
makes it so I can't read charts in the cockpit without taking them off.

I figured I would try a progressive lens because I thought it would
eliminate the extra task of taking my glasses off to look at a chart
(less work load is good right?), but I'm concerned about a few things:

1) the distortion of my peripheral vision for the top part of the lens,
let alone the bottom part.

2) the narrowness of the "corridor" that forces me to turn my head for
every single thing I want to look at... flight instruments and radios
are far enough apart to require a head turn.

3) can't view the entire width of a 81/2 piece of paper. I can only get
good focus on about 1/3 of it. The beginning and ends of the sentence
will be out of focus.

4) how much of my attention will be on getting my glasses to work vs.
looking out the window or at my instruments.

Any thoughts, ideas or personal experience you would care to relate
would be very much appreciated.

Thanks in advance.

On 2006-11-17, skyfish wrote:

I figured I would try a progressive lens because I thought it would

1) the distortion of my peripheral vision for the top part of the lens,
let alone the bottom part.

2) the narrowness of the "corridor" that forces me to turn my head for

Any thoughts, ideas or personal experience you would care to relate
would be very much appreciated.

I've had progressive lens for many years now and would never buy anything
else. I fly (VFR and IFR), play the piano and organ, as well as the usually
activities requiring different focal lengths and have no problem with any of
them.

If you wear glasses now, there may be an adjustment period, since your head
must move a very small amount for the correct portion of the lens, but this
will become unnoticed in a short period of time.

However, you should be aware that many companies produce several grades of
these progressive lens. The less expensive lens of several companies reduce
the width of the close focus range which is located at the bottom of the
lens. This might give a problem with the narrow focus range you mentioned.
But the more expensive of the range (I know a company who produces 3
different lens.) widens this area and you notice very little distortion at
the edges. This is a very important point!

The other important point is that they mark the correct pupil distance
before grinding the lens. This, fortunately, is done by most companies with
an electronic device and rather correct. My first pair was done with a
grease pencil and the results were less than favorable!

Some people can't adapt to these lens, as atested by some of the posts here,
but others, like me, really have no problem. Find a company who will
guarantee the lens and will exchange for a standard bi/trifocal set if you
are unsatisfied.

....Edwin
--
__________________________________________________ __________
"Once you have flown, you will walk the earth with your eyes
turned skyward, for there you have been, there you long to
return."-da Vinci http://bellsouthpwp2.net/e/d/edwinljohnson

I have the same problem (lack of accomodation). My solution is to have
a single vision lens (distance) in the left eye, and a bifocal in the
right eye (distance and sort-of-near).

Mainly I want good distance vision. I make a lot of use out of the High
Resolution Wraparound Plexiglass display common to most spam cans, and
distance vision is what is best there. The only reason I use near
vision is to see my charts. I have it set up so that the line is a few
millimeters lower than normal, and I do =not= put my reading
prescription there, but rather, a prescription for whatever it takes to
see the charts ON MY LAP. A stronger lens (bigger difference between
near and distance) makes an annoying visual break at the line, and my
approach plates are probably in my lap anyway.

I've tried it with the stronger lens... no go.

It takes a little getting used to the half and half thing (and my
optician wouldn't do it at first - I had to get my doctor to
specifically say on my prescription that I could get what I wanted).

I then have a =separate= pair of glasses for computer distance vision,
and had a set of clip-on +2 lenses made for reading. They were more
expensive than another set of glasses just for reading, but they are
much easier to carry around.

Jose
--
"Never trust anything that can think for itself, if you can't see where
it keeps its brain." (chapter 10 of book 3 - Harry Potter).
for Email, make the obvious change in the address.

Oh, one other thing. Big lenses.

Don't get little lenses. You need all the room you can get.

Jose
--
"Never trust anything that can think for itself, if you can't see where
it keeps its brain." (chapter 10 of book 3 - Harry Potter).
for Email, make the obvious change in the address.

Maybe this should be its own topic, but anyone have any success with either
an AME or the FAA getting approval for monovision lenses? (For those non
familiar, monovision implies correcting one eye for distance, one eye for
close. After several days, the brain 'figures it out'. ) I have
lived/functioned for about 6-7 years wearing one contact lens (to correct
distance). I think monovision can work equally well with either glasses or
contacts.

IIRC, about ten years ago there was an accident involving a plane which
crashed on final. It was blamed on the pilot's use of monovision. The FAA at
that time said 'no' to monovision. But also since that time doctors have
gotten better & smarter about its use. It seems the perfect solution for the
'mature' pilots who are losing distance vision, can correct for it, but then
once corrected, can no longer read (without further correction - bifocals or
switching glasses).

I wonder if those in the aviation medical community have caught up.
"skyfish" wrote in message
0...
I want to get current on my VFR Single Engine Land license but my eyes
are not what they used to be. The strength I need for good far vision
makes it so I can't read charts in the cockpit without taking them off.

I figured I would try a progressive lens because I thought it would
eliminate the extra task of taking my glasses off to look at a chart
(less work load is good right?), but I'm concerned about a few things:

1) the distortion of my peripheral vision for the top part of the lens,
let alone the bottom part.

2) the narrowness of the "corridor" that forces me to turn my head for
every single thing I want to look at... flight instruments and radios
are far enough apart to require a head turn.

3) can't view the entire width of a 81/2 piece of paper. I can only get
good focus on about 1/3 of it. The beginning and ends of the sentence
will be out of focus.

4) how much of my attention will be on getting my glasses to work vs.
looking out the window or at my instruments.

Any thoughts, ideas or personal experience you would care to relate
would be very much appreciated.

Thanks in advance.

pgbnh wrote:


IIRC, about ten years ago there was an accident involving a plane which
crashed on final. It was blamed on the pilot's use of monovision. The FAA at
that time said 'no' to monovision. But also since that time doctors have
gotten better & smarter about its use. It seems the perfect solution for the
'mature' pilots who are losing distance vision, can correct for it, but then
once corrected, can no longer read (without further correction - bifocals or
switching glasses).

Monovision contacts are still right out as far as the FAA is concerned.
Monovision LASIK (and the like) are OK.
I don't know how the FAA would feel about a monocle.

Margy got LASIK'd a while back, she now has bifocal reading glasses
(clear on top, reading correction on bottom).

I wonder if those in the aviation medical community have caught up.
"skyfish" wrote in message
20...
I want to get current on my VFR Single Engine Land license but my eyes
are not what they used to be. The strength I need for good far vision
makes it so I can't read charts in the cockpit without taking them off.

I figured I would try a progressive lens because I thought it would
eliminate the extra task of taking my glasses off to look at a chart
(less work load is good right?), but I'm concerned about a few things:

1) the distortion of my peripheral vision for the top part of the lens,
let alone the bottom part.

2) the narrowness of the "corridor" that forces me to turn my head for
every single thing I want to look at... flight instruments and radios
are far enough apart to require a head turn.


All progressive lens are not created equal. Many of the low cost store
brands like you would get at the major chains have a very narrow mid
range corridor. The Varilux brand has a much wider corridor, though
the more correction you need, the narrower it gets.

Don