Contact lenses vs Glasses

[AlexDeltaCharlie]

Hello all,

Just looking for some opinions on which type of corrective lenses are better for flying. I'm mildly short sighted and when flying I carry a normal pair of spectacles and a set of Aviator-shaped prescription sunglasses with large lenses. Flying under an overcast layer today I wore my normal clear spectacles and I really started to notice that my lookout for other traffic was struggling. My instructor pointed out another aircraft out the left window, and it took me a while to spot it myself. I suspect it was in my peripheral field of vision during the scan but I hadn't seen it because of not looking at it through my glasses. It occurred to me that because of the limited corrected field of vision through my spectacles my scan outside of the cockpit was not as effective as I'd previously thought, and that were I flying solo it would be possible to not see a conflicting aircraft altogether.

I've been looking into (excuse the pun) contact lenses recently and I was wondering whether they were a better choice for flying. Does anyone have any opinions of flying with contacts? Do they provide better peripheral vision, or is it better to invest in clear glasses with larger lenses? I really struggle with touching my eyes so it'd take a lot of getting used to I suspect, so do they provide a big benefit over spectacles?

ADC

[thing]

I may be wrong here but I thought you couldn't fly with contacts. I'm wondering whether I have blind spots in my varifocals. I took a non pilot passenger up the other day and he spotted two (non-radar notified) a/c before I did. I'm OK with 'movement against the background' targets, it's the non moving ones I have trouble picking up and they are the ones that kill you.

I took off from a small non controlled airfield yesterday and came close enough to a helo while climbing through 500 ft which I presume was doing line inspections for me to go 'Bugger.'

[riverrock83]

For airline work - contact lenses wouldn't work for most people (I suspect) due to the dryer air in the pressurised hulls causing them to dry out pretty quickly and become uncomfortable. You'd need to be constantly blinking to keep them moist. It is the advice to passengers so I presume it will be the same upfront! However, you don't have this issue in a typical GA plane...

See Guidance on Using Contact Lenses by Pilots | Medical | Personal Licences and Training (http://www.caa.co.uk/default.aspx?catid=49&pagetype=90&pageid=9243) for official (and surprisingly comprehensive) advice.

I wear prescription glasses / sunglasses in a plane but have tried contact lenses on the ground in the past. I've tried monthly ones and daily ones but the job I do (staring at a computer screen all day) meant that my eyes were stinging at the end of the day's work, so they just didn't work for me. They also had a habit of coming out at the most inopportune moments...

Also - it depends on whether you have slight astigmatism as well as distance correction (many people do without realising it). Glasses tend to correct this as well without you realising it while contact lenses don't. I found that I could see with a slightly better clarity with clean :O lenses than I could with contacts.

One other thing - no one likes the idea of putting things in their eyes but you soon get used to it - its not as bad as you think it is! There are a couple of different techniques so if you go for them - don't be afraid to try and find what works for you. I found a different technique to the one I was "taught" in the shop was quicker and easier for me - but everyone is different.

[vulcanpilot]

If you feel comfortable in "touching your eyeballs", which believe me, a lot of people aren't, then contacts are far superior to any form of spectacles, for so many reasons.

I've been using soft lenses now for something like 30 years, and now have silicon hydrogel high water content, high O2 permeable, extended wear lenses. Mine even correct for astigmatism (toric) and I wear for a week at a time, with one night per week off (yes, I keep them in overnight).

Lenses are ridiculously cheap these days, with a years worth of lenses costing about £130, plus the checkup/care costs.

The benefits of contacts are many, but include 'full peripheral vision' correction, not having to look through or past the edges of spectacle frames, less aberration (vertical lines are vertical, not slightly curved), no 'back of lenses' glare or reflection, and you can use an off-the-shelf pair of sunnies.....

Easy option is to ask your optician for a trial pair of lenses. But remember, if you do opt for contacts, you'll still have to carry a spare pair of spectacles and this will be endorsed on your medical - not sure how I'd deal with this though on the very, very unlikely event that a lens fell out in-flight, as I'd have to take the other lens out or I'd not be in any better position putting my specs on:ugh:

[thing]

So you can def wear contacts for flying then? I was under the impression that you couldn't. I'm of the 'carry a spare set of spectacles when flying' set as well.

[rans6andrew]

I have a couple of pairs of varifocal glasses, one set are sunglasses, and hate them both for anything beyond reading in bed. The distortion of the field of view, which changes as you move your head, is something I never got used to but the biggest downside is the amount of the scenery which is hidden behind the frames. I have worn my glasses for driving, once, I was quite un-nerved at road junctions when I was unsure whether there was something coming along which the frames were hiding. I also wore them for flying, twice, never again. The loss of peripheral vision caused me two scarey landings.

I took to contact lenses easily. Driving confidence restored so I tried them for flying, problem solved. Peripheral vision regained, no need to move the head to get what you want to see in the focal "sweet spot", no distortion of field, no need to buy prescription sunglasses ..... I have 30 day replacement soft lenses which I wear for up to 18 hours per day and rarely feel dry or tired eyes.

Works for me.

Rans6....

[Ds3]

I guess I'm luckier than most, but I wear contacts (for medium level short sightedness!) and very rarely have any issues with them, GA, commercial (as a passenger), or otherwise. In fact, 99% of the time I'm not even conscious I'm wearing them.

I wear the type that you stick in then forget about for 30 days (aside from taking them odd for a clean once every couple of weeks), even over night. The key is getting them in cleanly and quickly first time, then once in they're fine. Putting them in is no issue at all, you very quickly get used to the sensation of doing so, which really isn't much of a big deal.

On a commercial plane, they can get a tiny bit dry over an extended period of time, although this really applies to anywhere air conditioned. It's never been bad enough for me to feel the need to put drops in, so can't be all bad. For GA I have no issues at all, 20/20 vision all round and makes it much easier to take sunglasses on and off when required.

[thing]

Thanks for that, I have to take my glasses off to reverse the car (I only need them for close up work really) because the frames get in the way. What about when you go for the av med, can you still wear contacts or do you have to wear glasses.

[peterh337]

Glasses tend to correct this as well without you realising it while contact lenses don't

Is that really true?

I don't know - a real Q.

Most people who need correction do have some astigmatism, and in fact in a lot of cases (myself included) correcting the astigmatism alone (which on glasses is done with a cylindrical surface on the back of the lens) improves vision so much that no other correction is required to pass 20/20. In fact, glasses which didn't correct astig would be hardly worth having in my case.

On spotting other planes, I know this is not the often trotted out story, but actually they are hard to spot. Lookout is far less effective than most people think, and it is not for no reason that the RAF, following some fatal mid-airs, have just spent a vast amount (my guess: £20-25k per aircraft) fitting TCAS to all their Grob trainers. And these are the cream of the cream - instructors or pilots under training.

[thing]

On spotting other planes, I know this is not the often trotted out story, but actually they are hard to spot. Thank God, I thought it was just me. I've lost count of the times I've been told about traffic and asked if I'm visual with it yet. I'm always honest and say 'No contact' whereas everybody else seems to see a/c 200 miles away. I guess they might be fibbing a bit then.

[CharlieDeltaUK]

Another vote for contact lenses from me.

One point not mentioned so far: if you use contact lenses to correct your vision for short sight, you can in middle age find that you also need help with reading, and that means wearing specs. There's a lot of negative stuff (including on this thread) about varifocals etc. When I noticed I needed glasses (on top of my contact lenses) to read charts in my lap, I saw an optician who works near Brize Norton and had experience of advising pilots. Net result was a rather expensive pair of specs but they are engineered in all respects perfectly for flying. Optical technology has moved on.

The key thing is finding an optician who understands the demands of flying.

Re the question about how to use specs if you lose just one contact lens: you have two choices. You may find that you can function not too bad with one lens, but stereo vision can be a problem. So, you have a bit of time to sort yourself out, but don't try landing! At a push, reach for your specs and simply push out the lens which corresponds to the eye which has a contact lens still remaining. I've worn contact lenses for years and I never did get the hang of getting out lenses without a mirror - so don't fancy trying in the cockpit. I'll risk vandalising my specs to keep safe.

[abgd]

There's an interesting Australian report regarding pilot lookout:

www.atsb.gov.au/media/32918/limit_see_avoid.pdf

On page 9 there are theoretical reasons given why sea-and-avoid should only work a small percentage of the time. Arguably they're a bit pessimistic (e.g. in the circuit, you can to some extent predict where aircraft will come from, look in those spots, and improve your chances substantially; in the cruise, most conflicting aircraft are likely to be at your level, so you could see most but not all of them with a much narrower scan than the 180x30 degree scan specified).

Peripheral vision is good at motion detection, but it's the stationary, small aircraft that you're likely to collide with that you have to look out for, and you will see them best with your central vision that has good acuity. By the time they're large enough to be picked out in your peripheral vision, it's probably too late. So personally I'm sceptical that small-framed glasses would be that detrimental to lookout. Also, you can turn your head as well as your eyes, so the frames shouldn't cause 'blind-spots' to the same extent as pillars in the canopy may.

That said, there may be other times when peripheral vision is important - e.g. landing.

I used to wear contacts with wraparound glasses for hang-gliding, because it was much simpler and cheaper to update my prescription than to get prescription sports glasses made regularly. I found that the wind got in my eyes when I used regular spectacles. As someone with a real phobia of putting things in my eyes, it took me a lot of practice before I managed to get them in consistently, but I eventually got on well with them. I haven't felt a need for them recently though.

I've also asked opthalmologists (a profession that, like piloting requires both eyes) whether they would personally consider having laser treatment or using contacts... The answer has generally been 'no'.

[L'aviateur]

I use Acuview Moist Dailies, never have problems with dry eyes and very comfortable. Also carry a few spares in the car and a set of specs. I absolutely hate wearing specs.

As for earlier posting about whether contacts are allowed, well there is no prohibition for them in the rules and when I went for my Class 1 at Gatwick they had no problems with them.

[peterh337]

I've lost count of the times I've been told about traffic and asked if I'm visual with it yet

Enroute, perhaps 90% of contacts reported by a radar unit are never spotted - even if you have a plane full of pilots all looking for it.

This could be partly because I always fly as high as possible, and the majority of reported contacts are non-transponding and thus "level unknown" and they are usually flying very low. But for example I did a little local yesterday and got a contact reported at 5 miles. In the haze, one would not spot a 747 at 5 miles, and spotting a spamcan at 5 miles is very very hard at the best of times unless the contrast is excellent. In hazy wx, say 5k vis, most reported contacts will not be visible within the criteria for ATC telling you about them.

There is some apparently very good new laser surgery which corrects both distance and near vision but a friend of mine researched it and found it is banned by the CAA.

[Redbird72]

I believe he actually said that the contact lens will flatten the eye out a bit, but I'm not convinced I heard him correctly.

That part is true, the lense slightly flattens the eye and can alter your uncorrected prescription. I found that, when swapping regularly between contacts and glasses, I needed a slighly different glasses prescription & when I needed my "natural" eyesight to be tested, I was told to leave off the contacts for 10 days first.

I had a reasonable degree of astigmatism, and my contacts completely corrected it.

[peterh337]

There are contact lenses which you wear at night which will gradually partially correct small errors.

Might be handy for somebody who is just outside the uncorrected vision limits and who needs to get their initial CAA medical ;) though I was told by one optician selling them that a reputable optician would not supply them to somebody who was -6.5 or whatever.

[Cobalt]

There is some apparently very good new laser surgery which corrects both distance and near vision but a friend of mine researched it and found it is banned by the CAA.

If you are talking about someone who is both near-sighted (myopic) and suffers from age-related far-sightedness (presbyopia), I presume he means the KAMRA implant.

I am not surprised it is "banned" for pilots. This implant is a ring implanted in the cornea that narrows the pupil opening. The "pinhole effect" makes the image projected to the retina sharper (a theoretical pupil with a diameter of almost zero would project a sharp image without a lens!), but it makes the eye unsuitable for anything but good light conditions, and hence is normally only implaned in one eye.

If the choice is this or a pair of reading spectacles, I go for the latter.

[peterh337]

If it narrows the pupil opening, you might want to first photoshop any pics you put up on internet dating sites ;)

[It flies]

I have used both. In my experience both can be made to work very well. Contact lenses probably have the edge in sharpness but not by a large amount. In sunny weather the need for sunglasses negates the advantage of not wearing spectacles anyway.

The easiest way to try contacts is to use daily disposable lenses. These are the very thin foil type lenses. Putting them in just takes some practice. It's not that difficult. Any optician can show how to do it correctly. Even disposables are available with a correction for astigmatism. They are a bit harder to put in as they have direction markers on the lens. They work very well but are fairly expensive when used daily.

[AlexDeltaCharlie]

Thanks for all the replies, made for some interesting reading! It sounds like contacts would be worth a try. I've found some sites on the Web with advice on getting over the blink reflex as well which I think might take a bit of practise!

ADC

[peterh337]

They cannot possibly correct -7 to 0, from what I was told. That is about 5 times what they can do.

No doubt the CAA medical department is wise to anyone trying to use these to sneak under the limit anyway.

There is no way for the CAA or anybody else to tell you wear them at night. They also work slowly - over weeks or months.

[peterh337]

That's an interesting article...

However, they say

the effect of overnight OK lenses on corneal shape is temporary, and wears off over a few days if the lenses are not worn. To maintain the optical effect, lenses must be re-inserted and worn every night (or in some cases, every 2nd or 3rd night).

which is a quite different timescale to what I was told by one optician in Brighton selling them; he said the timescale they work on is weeks, not days.

Scarring is surely only from infections?

There is another aspect of this: if you sleep on your side, and the pillow pushes against your eye, that could squash the eye in the same way. I normally sleep on the RH side and sure enough my right eye has much more astig than the other. I wonder if anybody else notices this. It might explain why it sometimes appears that one's last eye test was duff; the resulting glasses don't work properly despite having spent a few hundred quid on them. Of course opticians normally blame crap eye tests on Specsavers... :E

[BackPacker]

I'm wearing hard contacts (-1.5 or thereabouts) and have been doing so for about 20 years. No problems when flying at all - even aeros.

Due to distortions at the edges of the frame I get a headache within 15 minutes if I switch to glasses so I have not worn those for a long time. In bed, with my lenses removed, I don't try to watch TV, but read a book instead (or watch the iPad).

On commercial airliners, or on hot days, I do get a bit irritation from the dry air. But that doesn't just mean my eyeballs are dehydrated - it means my whole body is dehydrated. So I use it as a sign to drink more, and that usually solves the problem. (It introduces another problem but that's not the subject of this thread.:})

My medical specifies that I need to bring a spare set of spectacles too when flying. I have substituted this with a spare set of lenses when I'm flying aeros. Easier to carry in my pants pocket - the glasses case would be quite a hazard if dislodged from the pocket when flying aeros. And of course I typically don't have a problem with two lenses at the same time. So I can simply replace the one that gives a problem, while leaving the other in place. But to be honest, with only -1.5 I can still see pretty decent shapes in the distance and I can probably land the plane just fine if it's just one lens that's missing. (Note that carrying spare lenses instead of spare glasses may not be legal, depending on the interpretation of the regulations and the interpretation of the word "spectacles". But common sense in this case tells me that it's probably safer, in my particular situation, to carry spare contacts instead of spare glasses.)

Hard contacts do take a week or two to get used to if you've never worn them before. But in the long run they're relatively cheap and pretty easy to maintain.

[cyberkryten]

I've been wearing contacts for 20 years (daily ones).

For the medical, I needed a prescription which also stated I've been wearing the lenses "constantly and successfully for over 8 hours for a period of at least one month" so if you aren't currently wearing lenses, then it may take a while before you can get to that stage.

I also have a Medical cert which states I must "carry a spare set of spectacles" - note that it says spectacles so I'm not sure that Backpacker's substitution of other contact lenses is acceptable (though his cert may be worded differently)??

To be honest, if I lost a lens in flight then it is _way_ easier to pop out the other lens and put on glasses (both of which for me are a one handed operation) than to find a very small lens packet, open it without dropping the lens (both hands needed), check the lens isn't inside out, and then try to insert the lens (again both hands and not clean ones, increasing the chance of irritants on the lens)...

[tulong]

I actually have had similar experience, but not necessarily with flying. It was reffing basketball. I am a contact lens wearer, but I got an eye irritation and couldn't wear my contacts. So I had to wear my glasses when reffing the basketball game and it was so difficult. I couldn't see anything out of my peripheral and there were times when I just couldn't see what I needed to. So I understand to a degree the frustration you are feeling.

Don't let being worried about touching your eye stop you from trying contacts. I promise you'll be able to overcome it and after a few weeks you'll wonder how you ever struggled in the beginning.

Also, as previously mentioned there is so many new developments in the world of contact lenses that even if your eyes are dry like mine, there are special contacts to help keep in moisture. But it is true that my eyes get dry on planes, and when your eye gets dry the eye gets a little irritated, but I am only wearing the Acuvue 2, not like the Acvue Oasys (http://www.ezyvision.co.nz/Acuvue_Oasys) or other contacts specially designed for dry eyes.

Some people who have astigmatism do see better with glasses than with contacts, but then again, their are contacts designed specifically for astigmatism (toric lenses). But it just depends on you.

If one of your contacts happens to pop out while you are flying you can just pop out the other one (as you practice taking them in and out you'll get the hang of taking them out quickly) and put on your glasses, or you can just fly with only one in for a short time until you can take care of it.

Advice: always carry your glasses, contact solution, and a contact case with you wherever you go and have them handy. You never know when you'll need it.