Spectacle lens design for helicopter pilot.

**iiiiisoptom** · 08-30-2010, 03:05 AM

Recently, a patient came in who is a 54 year old helicopter pilot. He is currently wearing a multifocal lens design (R&L +0.50 Add +2.50), but requires clear distance vision in the horizontal merdian, and as well in the right inferotemporal field for visual landing approaches. He has an instrument console at @45 degrees below the horizontal at @65cm, and also another intrument console @20 degrees above the horizontal at @30cm. Manifest refraction R +0.75/-0.75x122 L +0.50/-0.25x55 Add +2.50 @40cm.
I am thinking of putting him into a 28FT Bifocal Add +1.75, high set, into a large aviator style frame, so there is adequate inferotemporal field. I have not had great experience with occupational reverse segmented lenses ( for the superior near field), and would ask anyone who has had success when prescribing these lenses.

Many Thanks.

**kat** · 08-30-2010, 12:53 PM

Have you asked your optician what they would do?

**drk** · 08-30-2010, 01:07 PM

kat, you're rude. This guy's from Australia, so leave your petty inter-professional squabbling here in the U.S.

I think double-D is the way to go, mate.

**Robert Martellaro** · 08-30-2010, 02:37 PM

Plenty of good ideas here.

http://www.optiboard.com/forums/show...ear-For-Pilots

http://www.aoa.org/x5353.xml

I would think that you have no choice but to use a double D for the overhead panel.

Or a monocle.

I imagine that a helicopter pilot will look down during the landing and might need to see under or around the seg. Maybe one of the pilot forums can provide additional insight. Good luck.

**Judy Canty** · 08-30-2010, 03:35 PM

Originally Posted by drk

kat, you're rude. This guy's from Australia, so leave your petty inter-professional squabbling here in the U.S.

I think double-D is the way to go, mate.

...and you thought nothing was happening on OB! :shiner:

**drk** · 08-30-2010, 03:38 PM

Yeah, thanks kat!

She probably doesn't like the Wiggles or Paul Hogan either.

(Maybe it was Mel Gibson?)

**Ory** · 08-30-2010, 07:13 PM

Pick up a +1.75 fresnel lens. Cut a few 28 mm segs, and have him experiment by sticking them on the demo lenses of the frame he picked out while sitting in the cockpit. Once he finds the best location you can see if you would be best served with a double D or custom cemented segs.

**kat** · 08-30-2010, 07:20 PM

actually, I was really just wondering what his/her optician had suggested, then I was going to suggest a Double D or Double tri. Thanks, Drk

**uncut** · 08-30-2010, 08:34 PM

I couldn't help but notice his high add +2.50 and wonder what he/she has been using up til now....... and is this a Lasik patient?

I know that the request of OP is for a spectacle answer, but the contact lens fitter in me wonders whether a custom fitted RGP multifocal lens might be the best form of vision correction for this occupation.

**drk** · 08-30-2010, 09:40 PM

kat! We cartoon avatars must stick together :)

**rbaker** · 08-31-2010, 12:49 AM

Originally Posted by Robert Martellaro

Plenty of good ideas here.

http://www.optiboard.com/forums/show...ear-For-Pilots

http://www.aoa.org/x5353.xml

I would think that you have no choice but to use a double D for the overhead panel.

Maybe one of the pilot forums can provide additional insight. Good luck.

I have over 3000 hours of rotor wing time most of which was as a Marine Aviator and long before I became presbyopic and an additional 11,000 hours of fixed wing time about half of which while wearing multifocal lenses. PAL's are the least functional lenses for this application and flat top bifocals or trifocals are my lenses of choice. A double D would probably work just fine in this case.

**iiiiisoptom** · 08-31-2010, 08:28 PM

Thanks for all the constructive input guys. I did in fact ask "my" optician (we call them optical dispensers here), but as he had no experience with lenses for helicopter pilots, he had less clues than I did. I too was a bit surprised by the high (+2.50) Add for a 54 year old, but even though he gets 6/6+ or better acuity in each eye, he does have some evidence of macular pathology, which may be why he was originally ( not by me) prescribed this Add. He has currently been wearing a basic ( not free form) multifocal lens design, but has had to make significant postural adjustments when flying!!! Makes me wonder how safely/effectively he has been doing so to this point! My original thought was for a 28FT bifocal, and then when being informed about the overhead panel, for the occupational reverse segment. As I said, I have no experience in prescribing these for helicopter pilots, and wanted to know from those who do, or who in fact actually wear them when flying a chopper.

Thanks again. This place is the font of all (optical) knowledge :cheers:

**uncut** · 08-31-2010, 09:01 PM

If I could design an ultimate spectacle lens for this occupation, it would be a 35mm round, double smart-seg!

**Victa** · 09-01-2010, 05:45 AM

We have done a couple of pairs of specs for pilots lately. The option we went for was the double D, but they were put into a frame called a "High Rise" with an adjustible sliding bridge (Raises and lowers the frame front on the Client).

This may work for the chopper pilot, as he will be able to move the lower seg out of the way when required.