So why can’t I seem to fly with my prescription glasses?

[Missa]

Ok, So why can’t I seem to fly with my prescription glasses? Is it all in my head or does this have some medical biases?

I have an asymmetrical stigmatism that was uncorrected for 30 years. After getting regular headaches which aspirin had no affect on, starting behind my eyes, after working at the computer all day… the doctor said eye strain and the optometrist said I had only a slight nearsightedness in one eye but an asymmetrical stigmatism that could be causing the eye strain. I got the prescription for glasses and told that I could wear them or not wear them as I cared to, but I should wear them for three days straight to re-train my eyes to seeing the world the way everyone else did. I decided to try the glasses. Man, those three days were like walking through a carnival fun house. Everything slanted down and to the right. When I went shopping the first day I saw these really cool stools, they looks like standard wooden stools with a modern flair, the top was off set from the base. I wondered how they could be stable so walked up and touched one…BOOM… all of a sudden they were just regular stools… it was FREAKY. Slowly the funhouse effect when away and after the three days I really can’t see the difference between glasses on or glasses off (but now I only get headaches when I forget my glasses at home). In those three days I also learned not to look over or under the glasses and that glasses and showers don’t mix well. I now only wear my glasses in front of a computer or if my eyes are tired reading a book, but for nothing else. (I really hate the halo affect driving after dark).

But I digress…

When I first got my glasses I thought that my prescription glasses with the sun clips on would be great to fly in as I have the lightweight bendable titanium frames so they would not interfere with the headset. Where they were good for not interfering with my headset, after my instructor at the time adjusted the plane into what appeared to me to be a right wing low attitude I asked him what he was doing that for. He said he was leveling the wings (which is why he didn’t stay my instructor), I put the plane in “level” and asked if it was level to him… nope. I thought about it for a while and remembered back to the three ‘fun house’ days where things started looking right only after I gave myself some other input then just my sight. I figured that in the plane where I couldn’t touch the horizon I couldn’t get that other input to correct for my “corrected” vision.

Flash forward to this weekend when my sunglasses lost a screw. I didn’t have time to replace it and the only back-up sun glasses I had were my prescription sunglasses. I had an instrument lesson on Monday and figured since I trying to keep all the lines on the instruments lined up instead of keeping that distant horizon lined up it should be ok. But I couldn’t do it, I was all over the place and couldn’t keep the attitude indicator from rolling all over the place. My instructor therefore covered it… (hum first partial panel work) but I still had a LOT of trouble keeping my heading and altitude and was getting frustrated. I finally took off my glasses… and Melissa the decent instrument pilot magically returned (once the sun was kept out of my eyes with note pads binder clipped onto the visor).

So, Moral of the story… is there something going on here that explains why I can’t fly straight with my glasses on? My theory is that it deals with the inner ear inaccuracies, with only part time use of my glasses, the fact I’ve been compensating for the stigmatism for several years uncorrected and having no other way to discern which way is level… but how is that effecting me in instrument flight? My only concern is where I currently pass my medical w/o glasses, as I age if I become dependent on them to pass my medical, what good is it because I can’t seem to fly with them?

Missa
-wow, this is so much longer then I thought it was...

 

[Len Lanetti]

(I really hate the halo affect driving after dark).

Anti glare coating on the lens may help with the halo affect.

I think your best bet would be to talk to your dispensing optometrist about the vision requirements of flying the plane. Possibly a flying optometrist will respond to your post. Some of the things I would mention to your optometrist would be the requirement to use peripheral vision, the ability to easily go from seeing a chart to the panel to scanning for traffic (not always in that order). Take distance measurements from your eyes to the panel to provide the optometrist as well as bring an assortment of the charts you have to read.

It sounds like you are new to wearing glasses. I don't know enough to say this for certain but the "straight objects appear curved" phenomenon you describe doesn't sound right to me. If I picked up a new Rx for my glasses and experienced what you described I'd figure either I had too much to drink and need a cab ride home or there was a problem with the lenses.

Len

 

[Ken Ibold]

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It sounds like you are new to wearing glasses. I don't know enough to say this for certain but the "straight objects appear curved" phenomenon you describe doesn't sound right to me.

This is common and due to the astigmatism. I had profound astigmatism when I was younger, and in the early 80s had RK (then VERY experimental), which corrected it pretty well -- until I started sliding downhill in my early 40s.

When I bit the bullet and accepted a middle-ager's bifocals, my first few landings were darned near crashes. Then when riding from the airport with my dad driving, I noticed the curb looked 3 feet higher through my lenses than out the side of them (My glasses have rather small lenses) simply due to the refractions necessary to correct the astigmatism.

I think if your glasses are new you'll get used to them and fly well. For me, it took about a month before I really felt comfortable wearing them.

 

[RotaryWingBob]

This is common and due to the astigmatism. I had profound astigmatism when I was younger, and in the early 80s had RK (then VERY experimental), which corrected it pretty well -- until I started sliding downhill in my early 40s.

When I bit the bullet and accepted a middle-ager's bifocals, my first few landings were darned near crashes. Then when riding from the airport with my dad driving, I noticed the curb looked 3 feet higher through my lenses than out the side of them (My glasses have rather small lenses) simply due to the refractions necessary to correct the astigmatism.

I think if your glasses are new you'll get used to them and fly well. For me, it took about a month before I really felt comfortable wearing them.

That pretty well matches my experience, Ken. I have astigmatism as well, but no longer notice the distortion.

Here's a twist though. I cannot make a decent touchdown in a helicopter with bifocals on. I guess the reason is that they obstruct my peripheral vision at the bottom. So I have a set of regular glasses and sunglasses without the bifocal portion. Makes reading charts and stuff interesting...

 

[Len Lanetti]

This is common and due to the astigmatism.

Ken,

This is interesting as I have an astigmatism as well. Based on the difference in the curve of the right lens vs the left lens in my glasses I would say the astigmatism is significant in my right eye. That said, I've never noticed the straight objects appear curved problem. Possibly this is because I've been wearing glasses since before I can remember and my brain adapted to the visual input long ago.

Len

 

[Missa]

My glasses are not that new, I've had them about a year now, however I wear them only when I'm at the computer or maybe reading a book in the evening after working all day. Currently I do not need them to read charts, placards, checklists, the AFD etc. in the airplane. They are strictly computer associated headace prevention. I only tried them in the airplane because the arms were VERY thin and I was having trouble with the $15 Meijer sun glasses I was using. I decided not to use them and bought a pair of seringeti's that solved the pressure problem.

I do have anti-glare coating on my glases the 'halo' effect I was refering to is the illumination of the edge of the glasses caused by the ambient light. I feel like a raccon and it's distracting to me. Several of my glasses wearing freinds say you get use to it... but luckly I can read street sings without them so I don't wear them to drive.

Missa

 

[Missa]

Also, the Doctor told me to expect the 'leaning' (not curving) of eveything not only do I have a stigmatism but it is asymmetrical, the axis of the curivature of my lens is not vertival/horizontal but at an angle to the vertical (not common)... My football is leaning to one side.

Missa

 

[bstratt]

There is definitely an adjustment period involved in "retraining" the eyes. It takes my eyes about 30 seconds when switching from my glass 'glasses' to my plastic prescription sun glasses.

I would hazard a guess that you're not wearing them enough. Wear them every waking hour of every day for a couplke of weeks and see if that's fixing the problem. If that doesn't, then go back to the Doc.

 

[Jeff Oslick]

How big are your lenses? You might want to discuss with your optometrist whether a larger lens would help by giving better peripheral vision.

I wear contacts (have for many years), and only wear my glasses at home for less than an hour a day. I have a slight astigmatism that isn't corrected by my contacts, but is by my glasses, and definitely feel that I would have a bear of time trying to fly with my glasses because of the peripheral "bending" at the edge of the lens (though I do carry them while flying in case of a problem with the contacts).

Jeff

 

[dwh]

What you have described sounds like when I first got glasses in the third grade. They may have put a prism in the lens to compensate for the astigmatism. It takes several days to get past the flat surfaces looking curved. I only need glasses first for a weak eye muscle and then became nearsighted. You will probably have to wear the glasses all the time because your mind is translating what is being seen. What was flat looked curved and then it become flat again. Simialr to some one who only has vision in one eye. I have just gotten bivocals (no line) and have yet to try and land with them. They have created a distortion that is slowly leaving as well. The best suggeestion I can give you is that you need to always wear the glasses maybe with out the clip on sun glasses because they may be polarized lens that maybe having some affect as well.
Dale H.

 

[Len Lanetti]

Missa,

Another poster mentioned contacts. I had good luck with hard contacts even with my astigmatism and they did not cause the halos when driving at night. YMMV

Soft contacts did not work for me due to my astigmatism.

Len

 

[gibbons]

Soft contacts did not work for me due to my astigmatism.
Len

On the other hand, I've worn soft extended lenses for years - some with astigmatic correction (weighted) and some without. I've had good luck with contacts.

Chip

 

[bbchien]

Ok, So why can’t I seem to fly with my prescription glasses? Is it all in my head or does this have some medical biases?

I have an asymmetrical stigmatism that was uncorrected for 30 years.

Astigmatism is a "funny bunny". Imagine if you will a bowl in which someone has drawn a straight line- down one side, obliquely across the bottom and up the other. Now put a ripple in the near-to-bottom of the bowl. The line rides up across the ripple. But if the ripple isn't purpendicular to the line, the line will actually travel sideways up the ripple and back the other way down to rejoin the rest of the line. This is your plumb line across your retina.

Now over the years with your astigmatism as it was your brain adjusted for the cylindrical bulge in the retina. Your brain compensated for the slight diagonal across the ripple and back the other way. Now you change the formula in adult life and Viola!, brain can't cope.

Most of my astigmatic pilots make two pairs of every prescription. Heck, you can't get an aviation hamburger for the cost of the second pair. And, I'm not talking Maui Jims, here, I'm talking Lenscrafter's 2 for ones. Sure beats walking home when your primary pair fails. I have two, as well.

In clincial psychological testing, when subjects are made to wear inversion prisms (everything looks upside down) they stumble around for a few days hitting everything. On or about the fifth day they walk normally. The brain learns to cope. The trouble is, you can't go back and forth between systems.

That is why monovision burned in correction (one near, one far) is certifiable, butmonovision contacts are not. No telling what the brain will do if you can change systems, e.g, take them in and out. Like the AA captain did, landing in the rabbit at LGA ten years ago.

 

[Missa]

Ok, not sure if I got the answer I was looking for... I do not nor do I intend to wear my glasses for anything other then the computer. I take them off even when I walk to the bathroom (if I remember). Reading between the lines: This should not cause me a problem as long as I don't wear them in flight and can do all necessary flight tasks, and pass the medical without them. (as it hasn't so far)

If I even come to need to rely on them for any of the above, I have to start wearing them all the time. And once properly adjusted to this "new" way of being, I should be fine as well.

Other then the brain does funny things I'm still not sure why I couldn't seem to hold straight and level flight in reference to just instruments with them on, but could when I took them off (my normal state of being unless I'm sitting in front of a computer). It just seems weird and I'm a curious sort of person.

Missa

 

[bbchien]

Right on all counts. I think that the bottom line is that the brain uses peripheral cues to process what it sees. Change the cues erratically and it becomes a Zoo. FAA doesn't care so long as you can pass the ride and read the chart, and actually HAVE peripheral vision.

 

[gismo]

Normally, astigmatism correction is done by combining cylindrical correction with the spherical one. The goal of the cylindrical correction is to get the light rays coming from a point to all land on the same spot on your retina. Without the cylindrical correction some rays end up displaced along the axis where the correction is needed. Unfortunately AFaIK there is no way with a single lens system to achieve cylindrical correction for focus without introducing some geometric distortion due to the different magnification on and off the cylindrical axis. IOW lines at angles other than 90 degrees from your correction axis will not appear to have the same angle between them to you compared to a person with no astigmatism. Fortunately the brain is pretty good at morphing the image on your retina into what you expect something to look like.

BTW contact lenses correct for astigmatism in an entirely different (non-refractive) manner. Basically they force the cornea to lose much of it's aspherical shape and resulting astigmatism. If your astigmatism is primarily due to the shape of your lens and cornea, as opposed to shape distortion of the retina surface itself, this might work quite well. You might want to try them to see if that method suits you better. My eyesight correction is also primarily astimatic in one eye and this works for me much better than any glasses I ever had.

 

[Missa]

NO Contacts, NEVER NEVER NEVER NEVER NEVER NEVER NEVER NEVER NEVER NEVER NEVER NEVER NEVER NEVER NEVER NEVER NEVER NEVER NEVER NEVER NEVER NEVER NEVER NEVERNEVER NEVER NEVER NEVER NEVER NEVER NEVER NEVER NEVER NEVER NEVER NEVER !!!!!!

I have this thing about stuff touching my eyes.... Because of this when I was in first grade I had a very BAD trip to the optomitrist. My mom, dad and the nurse all had to hold me down while the doctor tried to put drops in my eyes to dialate them. I put up such a fuss and was screaming bloody murder the whole time that the doctor then decided not to un-dialte them and let them go back on their own. I didn't go back to the optomitrist untill about 18 years later when I was having headaches in collage... Luckly my eyes hadn't changed a bit which he said was good. On that visit he asked if I was doing a lot of reading... Hum, week before finals in Engineering... only about 18 hours a day Doc. Well, I could give you a persciption of this little correction you need or you could try to take a few minutes and focus at a distance when reading. (poor uninsured collage student took the cheep "try this" method). About 7 years later I finally took the perscription but only for when I work at he computer... now, he wants me to come see him every year.

Missa

 

[Len Lanetti]

NO Contacts, NEVER NEVER NEVER NEVER NEVER NEVER NEVER NEVER NEVER NEVER NEVER NEVER NEVER NEVER NEVER NEVER NEVER NEVER NEVER NEVER NEVER NEVER NEVER NEVERNEVER NEVER NEVER NEVER NEVER NEVER NEVER NEVER NEVER NEVER NEVER NEVER !!!!!!

Missa,

FYI...you're not 5 anymore. :<)

Try contacts you might like them. One great benifit you can wear any cool looking sunglasses you want and still be able to see to read.

Len

 

[Missa]

Missa,

FYI...you're not 5 anymore. :<)

Try contacts you might like them. One great benifit you can wear any cool looking sunglasses you want and still be able to see to read.

Len

No, I'm not 5, but I still have trouble letting people, even those I trust, touch my eyes... and have not been able to do it myself.

Seeing that I can read without my prescription glasses on* I can wear any cool sunglasses I like and am able to see and read.

Missa
*the only time I would need to have my vision corrected in the sun would be if I were to spend 5-8 hours on my computer in the direct sunlight... seeing that at work I don't sit near the window and at home the computer is in the basement. I'm not sure this would ever happen.

 

[Len Lanetti]

No, I'm not 5, but I still have trouble letting people, even those I trust, touch my eyes... and have not been able to do it myself.

Seeing that I can read without my prescription glasses on* I can wear any cool sunglasses I like and am able to see and read.

Missa,

Whoops. Sorry I must have missed the part about you not needing your glasses to read.

You know now, of course, that to put drops in your eyes the bottle or dropper shouldn't actually touch your eye.

For me, putting contacts in is 1,000 times easier to tolerate as compared to getting my retna checked each year by the eye doc.

Len

 

[Missa]

Missa,

You know now, of course, that to put drops in your eyes the bottle or dropper shouldn't actually touch your eye.

Len

Yes, but to put a contact in or get a chip out I would have to touch my eye...I am :~princess Queen of the saftey glasses!

Drops are still a problem becaue of the fluid in the drop touching my eye... when I HAVE to it's usually a fight with myself I have to hold my lower lid down and try to drop as the top lid trys despratly to keep open/closed(reflex) and it's usually half the drops end up on my face...

Missa
Still not intrested in puchasing something I don't think I'll ever be able to put in let alone get out...

 

[Greebo]

Hmm... totally unrelated, but I see we have a problem with the princess smiley.

 

[Len Lanetti]

Yes, but to put a contact in or get a chip out I would have to touch my eye...I am :~princess Queen of the saftey glasses!

Missa,

When you put the contact in you are touching the contact and then the contact makes contact with your eye. So, technically, you are not actually touching your eyeball. :<)

To take my hard contacts out I just held the skin at the outside corner of my eye a little more to the outside and the contact would pop out.

As I've worn glasses for about 95% of my lifetime waking hours the biggest fear I had when wearing contacts was not having my glasses on to protect my eyeballs. This really manifested itself when I learned to fence.

Len

 

[Missa]

Missa,

When you put the contact in you are touching the contact and then the contact makes contact with your eye. So, technically, you are not actually touching your eyeball. :<)

Ok, ok... but i hate it when ANYTHING touches my eye.... get it now?

This really manifested itself when I learned to fence.

Len

Ooo fencing how cool! something I've always wanted to learn....

Missa

 

[Greebo]

Ok, ok... but i hate it when ANYTHING touches my eye.... get it now?

So have you ever considered contact lenses?











Sorry - I had to...

 

[Missa]

So have you ever considered contact lenses?

Sorry - I had to...

Why I autta! <smack!> :zap!: :zap!: :zap!:

Pain....

Missa

 

[Len Lanetti]

Dueling

Ooo fencing how cool! something I've always wanted to learn....

Missa,

It is very neat...the whole Erol Flynn, 3 Musketeers mystique when you fight with the foil. Saber is neat too, for me, less style but more aggressive...Darth Maul, Quin Quon Gin like.

Len

 

[Missa]

Re: Dueling

Missa,

It is very neat...the whole Erol Flynn, 3 Musketeers mystique when you fight with the foil. Saber is neat too, for me, less style but more aggressive...Darth Maul, Quin Quon Gin like.

Len

The whole fairy tail/damsel in distress mystique is what makes fencing attractive and cool...

Missa
-Of course, my fairy tails all end with the damsel kicking the bad guy's A$$...

 

[Ghery]

Most of my astigmatic pilots make two pairs of every prescription. Heck, you can't get an aviation hamburger for the cost of the second pair. And, I'm not talking Maui Jims, here, I'm talking Lenscrafter's 2 for ones. Sure beats walking home when your primary pair fails. I have two, as well.

My second pair is in a hard case in my flight bag. If I had a third pair, they'd be in the center console of my Jeep. I am going back to larger lenses next time. My current pair just doesn't provide the coverage that the ones in my flight bag do without having to turn my head.