VISION THREAD (other than colour vision)
niknak
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Your frustration is completely understandable, but for advice, please go back to the CAA Medical Department.
Whatever your problem may be, if you treat them with respect, they will do their utmost to assist you and get you back to the standard you require.
I can speak from personal experience, if you do what they need of you, they will do their best for you, but you should bear in mind that they are the Regulator and technically, they are not obliged to do anything more than advise you of the requirement.
Whatever your problem may be, if you treat them with respect, they will do their utmost to assist you and get you back to the standard you require.
I can speak from personal experience, if you do what they need of you, they will do their best for you, but you should bear in mind that they are the Regulator and technically, they are not obliged to do anything more than advise you of the requirement.
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I've emailed them tonight regarding the matter and said that I am willing to do anything that is required of me to gain my Class 1 Medical so that I may procede to CPL after my PPL... Thanks for your advice... If anybody else can share their experiences with me I would appreciate some "pick me up" as this has come as a major blow to be at present.
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Astigmatism
Hello NurseToPilot,
As you say, your right eye at -3.25 is the problem with the renewal limit being -3.00.
You might be aware that a new set of medical standards are about to be applied (1st or 4th Dec) which include new eyesight requirements on Class 1s. Dioptre limits for myopia have been extended, but for hyperopia they remained the same. Limits for astigmatism remained the same, -2.00 for initial issue and -3.00 for renewal. However, the wording has now been changed to allow the medical examiner to exercise discretion and allow a pilot with astigmatism of beyond 3.00 diopteres to be certified fit to fly commercially.
You mention a deviation on your class 2 that is removed when you get your PPL; the same thing happens with the Class 1 and a CPL. The deviation route to a full medical was an initiative argued by the CAA at the JAA medical sub-committee meetings to assist with harmonisation of medical standards across the EU.
There was some talk a few weeks ago about the CAA stopping medicals with deviations, but this may have been rumours. The CAA have said that they are not aware of any imminent changes that would affect their ability to issue deviations other than transition of licensing powers to EASA, which (I think) will not happen for at least 12 months yet.
Obviously I can't talk for the CAA, but you're specs prescription indicates that you're outside of the current limits for a deviation. It is difficult to measure astigmatism accurately (subjectively, anyhow) and so it may well be possible for you to get a specs prescription for your right eye which is -3. However, given that the new limits now allow some judgement on astigmatism at renewal, the CAA may be OK with 3.25.
Keep pushing with the CAA - I can understand how you might be feeling, but I persevered for 9 years from initally applying for a class 1 and actually getting one, all as a result of excess astigmatism. I spent most of my late teens and early twenties feeling disappointment that I would never be able to fly commercially, but I now have a chance. Don't give up. If the CAA say no, just remember that things can change.
Would be good to hear how you get on. Drop me a message if I can offer any other advice. Good luck
waterpau
As you say, your right eye at -3.25 is the problem with the renewal limit being -3.00.
You might be aware that a new set of medical standards are about to be applied (1st or 4th Dec) which include new eyesight requirements on Class 1s. Dioptre limits for myopia have been extended, but for hyperopia they remained the same. Limits for astigmatism remained the same, -2.00 for initial issue and -3.00 for renewal. However, the wording has now been changed to allow the medical examiner to exercise discretion and allow a pilot with astigmatism of beyond 3.00 diopteres to be certified fit to fly commercially.
You mention a deviation on your class 2 that is removed when you get your PPL; the same thing happens with the Class 1 and a CPL. The deviation route to a full medical was an initiative argued by the CAA at the JAA medical sub-committee meetings to assist with harmonisation of medical standards across the EU.
There was some talk a few weeks ago about the CAA stopping medicals with deviations, but this may have been rumours. The CAA have said that they are not aware of any imminent changes that would affect their ability to issue deviations other than transition of licensing powers to EASA, which (I think) will not happen for at least 12 months yet.
Obviously I can't talk for the CAA, but you're specs prescription indicates that you're outside of the current limits for a deviation. It is difficult to measure astigmatism accurately (subjectively, anyhow) and so it may well be possible for you to get a specs prescription for your right eye which is -3. However, given that the new limits now allow some judgement on astigmatism at renewal, the CAA may be OK with 3.25.
Keep pushing with the CAA - I can understand how you might be feeling, but I persevered for 9 years from initally applying for a class 1 and actually getting one, all as a result of excess astigmatism. I spent most of my late teens and early twenties feeling disappointment that I would never be able to fly commercially, but I now have a chance. Don't give up. If the CAA say no, just remember that things can change.
Would be good to hear how you get on. Drop me a message if I can offer any other advice. Good luck
waterpau
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If you are a pilot flying an aircraft with EFIS the Health & Safety (Display Screen Equipment) Regulations 1992 cover this and whilst they do not relate specifically to aircraft the Civil Aviation (Working Time) Regulations 2004, Regulation 6, which applies to all aircrew, both flight and cabin crew, requires all employers to provide adequate health and safety arrangements for all employees.
The DSE Regs state:
"display screen equipment" means any alphanumeric or graphic display
screen, regardless of the display process involved.
IIRC, ATC Radar operators are specifically mentioned in the guidance document L28 but I am certain these regulations would also apply to EFIS operators, however, coal powered aircraft with iron dials are a different story.
The CAWTR 2004 would then refer back to Reg 5 of the DSE Regs, which entitles any person, being a display screen equipment 'user', i.e. an employer using display screen equipment for a significant part of the working day, to undertake eye examinations at suitable intervals (usually every 2 years).
Section 9 of the Health & Safety at Work Act 1974 expressly forbids any employer from levying or permitting to be levied any charge against an employee for anything done in the course of his employment which is connected with his health and/or safety.
Eye tests are normally done by larger companies under Eye Voucher schemes but smaller companies just reimburse the examinee the cost. The cost of any spectacles is also required to be met by the company - this only extends to the basic specs; any special frames, etc. have to be paid for by the examinee.
If a company required any individual to have more frequent eye tests owing to a stipulation in any Ops Manual, I believe that these tests would also be covered under the DSE Regs and the company responsible for the costs.
If you are in doubt, check with the CAA's health and safety adviser who is responsible for the regulation and enforcement of this area, e-mail at [email protected] or check with your own company's H&S Manager.
HTH
2close
The DSE Regs state:
"display screen equipment" means any alphanumeric or graphic display
screen, regardless of the display process involved.
IIRC, ATC Radar operators are specifically mentioned in the guidance document L28 but I am certain these regulations would also apply to EFIS operators, however, coal powered aircraft with iron dials are a different story.
The CAWTR 2004 would then refer back to Reg 5 of the DSE Regs, which entitles any person, being a display screen equipment 'user', i.e. an employer using display screen equipment for a significant part of the working day, to undertake eye examinations at suitable intervals (usually every 2 years).
Section 9 of the Health & Safety at Work Act 1974 expressly forbids any employer from levying or permitting to be levied any charge against an employee for anything done in the course of his employment which is connected with his health and/or safety.
Eye tests are normally done by larger companies under Eye Voucher schemes but smaller companies just reimburse the examinee the cost. The cost of any spectacles is also required to be met by the company - this only extends to the basic specs; any special frames, etc. have to be paid for by the examinee.
If a company required any individual to have more frequent eye tests owing to a stipulation in any Ops Manual, I believe that these tests would also be covered under the DSE Regs and the company responsible for the costs.
If you are in doubt, check with the CAA's health and safety adviser who is responsible for the regulation and enforcement of this area, e-mail at [email protected] or check with your own company's H&S Manager.
HTH
2close
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Eye eye!!
Hi i wonder if anyone can help solve this puzzle?
Am currently working towards my PPL, and looking to start ATPL g/school next summer, and going the whole hog!!
I had my class 2 medical done about 2 months ago, and everything was fine, apart from my right eye being a little bit weaker than my left.
The CAA doctor told me that, due to this it would restrict me from gaining a class 1 medical certificate, and would have to get glasses or contact lenses e.c.t
But today i went into vision express for an eye test, and they carried out various tests, of which all were fine, they could see my right eye was slightly weaker, but they said my vision is better than 20/20 both eyes, and both can resolve as much detail when one eye is covered up???
They said that they could see NO reason why i wouldn't be able to gain a class 1, so why when i had my class 2 done, was i told that i wouldn't pass a class 1 becuase of my right eye??
Any help would be much appreciated
Lee
Am currently working towards my PPL, and looking to start ATPL g/school next summer, and going the whole hog!!
I had my class 2 medical done about 2 months ago, and everything was fine, apart from my right eye being a little bit weaker than my left.
The CAA doctor told me that, due to this it would restrict me from gaining a class 1 medical certificate, and would have to get glasses or contact lenses e.c.t
But today i went into vision express for an eye test, and they carried out various tests, of which all were fine, they could see my right eye was slightly weaker, but they said my vision is better than 20/20 both eyes, and both can resolve as much detail when one eye is covered up???
They said that they could see NO reason why i wouldn't be able to gain a class 1, so why when i had my class 2 done, was i told that i wouldn't pass a class 1 becuase of my right eye??
Any help would be much appreciated
Lee
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increasingly PPRUNE should be known by another name, more consistent with the point of view of the european and UK pilot.
By the way, in the USA the same physician who takes your blood pressure also checks your vision for the FAA required medical certificate.
he also takes an EKG ( ecg to some)
checks your ears
has you hop up and down on one leg
and all that jazz.
And we have to pay for it ourselves at my major airline. For a first class (captain requires) the cost can range up to 130 US dollars every 6 months. It takes less than half an hour assuming you have had some water to drink prior to arrival. ;-)
By the way, in the USA the same physician who takes your blood pressure also checks your vision for the FAA required medical certificate.
he also takes an EKG ( ecg to some)
checks your ears
has you hop up and down on one leg
and all that jazz.
And we have to pay for it ourselves at my major airline. For a first class (captain requires) the cost can range up to 130 US dollars every 6 months. It takes less than half an hour assuming you have had some water to drink prior to arrival. ;-)
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Ghost Rider,
It sounds like the AME may have got this wrong. AME's are not eye specialists, unlike the optometrist.
The best way to solve this would be to go to Gatwick and have your Class 1 medical.
You should really do this before undertaking any advanced training, including ATPL GS, otherwise, if the medical turns up something you were unaware of you may be burning a large amount of cash for nothing.
You will have to pay for the medical up front but you can ask for the eye test first and if you fail that you can stop the medical there and then and be reimbursed the fee (less the eye test cost).
HTH
2close
It sounds like the AME may have got this wrong. AME's are not eye specialists, unlike the optometrist.
The best way to solve this would be to go to Gatwick and have your Class 1 medical.
You should really do this before undertaking any advanced training, including ATPL GS, otherwise, if the medical turns up something you were unaware of you may be burning a large amount of cash for nothing.
You will have to pay for the medical up front but you can ask for the eye test first and if you fail that you can stop the medical there and then and be reimbursed the fee (less the eye test cost).
HTH
2close
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David
A good post and it reflects my experience of the Holmes Wright test some 6 years ago. As usual the CAA does not seem to be using the tests in the manner that they were originally designed to be used, Holmes and Wright, whoever they were designed the lanterns but I am almost sure that the validity of the results achieved by a person would be based upon carrying out the test in a particular way. I understand that it is common in research that they would validify the findings and therefore the ability of the lantern to produce correct results using by prescribing the method in which the test is carried out. This is usually the method and 'rules' that have been used during research and hence those used to produce results demonstrating the validity of the test.
Anyway.......the JAR manual states the following in relation to the Holmes Wright lantern, and if what you say is correct the test certainly hasn't been carried out in accordance with this. An extract for the manual is as follows:
The Holmes-Wright lantern has an aperture size of 1.6 mm, corresponding to a visual angle of 0.9 minutes of arc. The light intensity is 2 000 m-candelas for demonstration, 200 m-candelas for daylight testing and 20 m_-candelas for testing in complete darkness. [The latter not used by City University or by the UK CAA.] The lantern is easy to use. The examinee is placed in front of the lantern at a distance of 6 metres.
Five different colours are presented: two red, two green, and one white light stimulus in nine different combinations, each presenting two colours (which may be identical in some of the presentations). The 2 x 9 fixed stimuli are presented for two to three seconds each and the examinee must identify the colour of each without delay. If all colours are correctly identified, the lantern test has been passed. If the examinee makes two or more errors, the lantern test has not been passed and the examinee is classified as colour unsafe. If the examinee makes one mistake or shows uncertainty during the test run, the lantern test is re-performed by executing two consecutive
A good post and it reflects my experience of the Holmes Wright test some 6 years ago. As usual the CAA does not seem to be using the tests in the manner that they were originally designed to be used, Holmes and Wright, whoever they were designed the lanterns but I am almost sure that the validity of the results achieved by a person would be based upon carrying out the test in a particular way. I understand that it is common in research that they would validify the findings and therefore the ability of the lantern to produce correct results using by prescribing the method in which the test is carried out. This is usually the method and 'rules' that have been used during research and hence those used to produce results demonstrating the validity of the test.
Anyway.......the JAR manual states the following in relation to the Holmes Wright lantern, and if what you say is correct the test certainly hasn't been carried out in accordance with this. An extract for the manual is as follows:
The Holmes-Wright lantern has an aperture size of 1.6 mm, corresponding to a visual angle of 0.9 minutes of arc. The light intensity is 2 000 m-candelas for demonstration, 200 m-candelas for daylight testing and 20 m_-candelas for testing in complete darkness. [The latter not used by City University or by the UK CAA.] The lantern is easy to use. The examinee is placed in front of the lantern at a distance of 6 metres.
Five different colours are presented: two red, two green, and one white light stimulus in nine different combinations, each presenting two colours (which may be identical in some of the presentations). The 2 x 9 fixed stimuli are presented for two to three seconds each and the examinee must identify the colour of each without delay. If all colours are correctly identified, the lantern test has been passed. If the examinee makes two or more errors, the lantern test has not been passed and the examinee is classified as colour unsafe. If the examinee makes one mistake or shows uncertainty during the test run, the lantern test is re-performed by executing two consecutive
runs of the nine presentations. No errors or mistakes are allowed during this second run.
I wonder what Mr Holmes and Mr Wright criteria were to claim the validity of the lantern? Bet you it is not the same as the CAA!!!!
I wonder what Mr Holmes and Mr Wright criteria were to claim the validity of the lantern? Bet you it is not the same as the CAA!!!!
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eye eye
Thanks very much 2close, what you've said is what i thought!! Im going to book my Class 1 medical a.s.a.p before i embark on further professional training
Thanks Lee
Thanks Lee
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You mentioned that your astigmatism is outside the limits. This prescription also shows excessive anisometropia. The difference between your eyes is 3.75 dioptres; the Class 1 initial limit is 2.0 dioptres, and the "soft" limit for renewal is 3.0 dioptres.
For reference, the JAA has now published Amendment 5 to JAR-FCL 3 [PDF, ~750 KB].
Last edited by LastMinute; 1st Dec 2006 at 02:08.
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Color Blindness Test, Dont Worry!
COLOR BLINDNESS TEST, DONT WORRY!
I was down at the CAA a few months ago for an unrelated reason. I was in the the doctors office who is the head man down at the unit.
He told me that the CAA will accept ant type of colour blindness test that is accepatble to any JAR country (apparently there a 3 types) He also logged on on his computer and showed me the City test which he said the CAA had paid for the research and this is the test they will eventually want to use and they want all the other JAR countries to follow suit. The new test simulates the colours/hues pilots will come accross in glass cockpit aircraft.
I havnt read all the previous posts so i am sorry if i have duplicated what has already beed said. This Doctor I might mention is one of the most helpful, friendly individuals I have met at the CAA and is very approachable.
So if you have a problem make sure you speak to him he also said we try here to enable people to get a licence not prevent them from having one.
So dont take to much notice of some of the negatives on here as with anything go straight to the horses mouth rather than the other end which appears on here regulary.
SEE you around!
I was down at the CAA a few months ago for an unrelated reason. I was in the the doctors office who is the head man down at the unit.
He told me that the CAA will accept ant type of colour blindness test that is accepatble to any JAR country (apparently there a 3 types) He also logged on on his computer and showed me the City test which he said the CAA had paid for the research and this is the test they will eventually want to use and they want all the other JAR countries to follow suit. The new test simulates the colours/hues pilots will come accross in glass cockpit aircraft.
I havnt read all the previous posts so i am sorry if i have duplicated what has already beed said. This Doctor I might mention is one of the most helpful, friendly individuals I have met at the CAA and is very approachable.
So if you have a problem make sure you speak to him he also said we try here to enable people to get a licence not prevent them from having one.
So dont take to much notice of some of the negatives on here as with anything go straight to the horses mouth rather than the other end which appears on here regulary.
SEE you around!
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Hi, this might help you
"The Spectrolux lantern has twelve vertical pairs of combinations of red, green, or white lights, with two different intensities and hue of each color. The difference in luminance is relatively large in some of the pairs of lights, for example, white (413 cd · m-2) and green (27 cd · m-2), and two whites-the only large difference being in luminance (416 and 50 cd · m-2). A total of 2 runs of the 12 pairs were carried out in the same order each time, and every color had to be named correctly (as 'red,' 'green,' or 'white') to pass. No demonstration of colors prior to the test was given, but subjects were advised of the colors they could expect."
Taken out of this Text:
http://www.ingentaconnect.com/conten...0005/art00001l
regards
G/A
"The Spectrolux lantern has twelve vertical pairs of combinations of red, green, or white lights, with two different intensities and hue of each color. The difference in luminance is relatively large in some of the pairs of lights, for example, white (413 cd · m-2) and green (27 cd · m-2), and two whites-the only large difference being in luminance (416 and 50 cd · m-2). A total of 2 runs of the 12 pairs were carried out in the same order each time, and every color had to be named correctly (as 'red,' 'green,' or 'white') to pass. No demonstration of colors prior to the test was given, but subjects were advised of the colors they could expect."
Taken out of this Text:
http://www.ingentaconnect.com/conten...0005/art00001l
regards
G/A
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I'm afraid this isn't going to help cheer you up, but...
You mentioned that your astigmatism is outside the limits. This prescription also shows excessive anisometropia. The difference between your eyes is 3.75 dioptres; the Class 1 initial limit is 2.0 dioptres, and the "soft" limit for renewal is 3.0 dioptres.
You mentioned that your astigmatism is outside the limits. This prescription also shows excessive anisometropia. The difference between your eyes is 3.75 dioptres; the Class 1 initial limit is 2.0 dioptres, and the "soft" limit for renewal is 3.0 dioptres.
I dont mean to be argumentative and im OBVIOUSLY trying everything i can to get round this and make it so the only way i can SEE it in my mind is to put it down on paper... I make the DIFFERENCE between my two eyes 2.75... cos we're NOT adding together the figures here but merely measuring the distance between two points....
see image below... It seems to make sense to me...(but i am desperate now)
even on a calculator you would work it out as follows:
(-3.25) - (-0.50) = -2.75
Last edited by NurseToPilot; 2nd Dec 2006 at 00:52.
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N2P:
Your left eye correction is 2.00 dioptres (the spherical component alone) along the 22.5° axis and 2.00 + -3.25 = -1.25 dioptres (spherical plus cylindrical component) along the perpendicular (112.5°) axis. So the worst error for this eye is 2.00 dioptres. (That is the "deviation from emmetropia in the most ametropic meridian" referred to in JAR-FCL 3 3.220(b).)
Your right eye correction is -1.25 dioptres along the 180° axis and -1.25 + -0.50 = -1.75 dioptres along the perpendicular (90°) axis. So the worst error for this eye is -1.75 dioptres.
Your degree of anisometropia is the difference between the two worst cases - i.e., 2.00 - -1.75 = 3.75 dioptres.
I should point out that I am not an optometrist so I may be completely wrong on this. But this is what I believe the numbers mean. Sorry it's bad news for you. (If it's any consolation, I can't even get a Class 2 due to my short sight being beyond the limits. Looks like I'll stay a wannabe until they relax the limits a bit more...)
Your left eye correction is 2.00 dioptres (the spherical component alone) along the 22.5° axis and 2.00 + -3.25 = -1.25 dioptres (spherical plus cylindrical component) along the perpendicular (112.5°) axis. So the worst error for this eye is 2.00 dioptres. (That is the "deviation from emmetropia in the most ametropic meridian" referred to in JAR-FCL 3 3.220(b).)
Your right eye correction is -1.25 dioptres along the 180° axis and -1.25 + -0.50 = -1.75 dioptres along the perpendicular (90°) axis. So the worst error for this eye is -1.75 dioptres.
Your degree of anisometropia is the difference between the two worst cases - i.e., 2.00 - -1.75 = 3.75 dioptres.
I should point out that I am not an optometrist so I may be completely wrong on this. But this is what I believe the numbers mean. Sorry it's bad news for you. (If it's any consolation, I can't even get a Class 2 due to my short sight being beyond the limits. Looks like I'll stay a wannabe until they relax the limits a bit more...)
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oh well... i tried.
I find the rules rediculous... The whole point of wearing contacts/ glasses is to "correct" your vision... So if you can see 20/20 WITH correction where is the problem?
One would never fly without wearing his / her corrective lenses
I find the rules rediculous... The whole point of wearing contacts/ glasses is to "correct" your vision... So if you can see 20/20 WITH correction where is the problem?
One would never fly without wearing his / her corrective lenses
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The JAA Manual of Civil Aviation Medicine gives some explanation of why there are limits. It's all to do with the optical effects induced by correcting lenses.
Chapter 13, section 4.3 "Spectacle correction of ametropia" states:
Actually I think the UK CAA is keen to get the "irrelevant" limits abolished. But bear in mind that there are 32 other member states of the JAA that get to vote on the standards, and not all of them agree.
Chapter 13, section 4.3 "Spectacle correction of ametropia" states:
One of the reasons for setting an upper limit is the optical aberrations caused by correcting lenses. These optical errors increase with increasing lens power and towards the edge of the lens. With modern materials used in high-quality correcting glasses problems are most unlikely to occur inside the range of ±5·0 dioptres.
Distortion of the image due to peripheral angular magnification narrows the effective visual field.
The prismatic deviation gives rise to double vision in myopes and a ring scotoma in hyperopes.
In anisometropia, the refractive state is different in the two eyes. When corrected with glasses, these give a dissimilar magnification – a condition known as aniseikonia. The illusion created is particularly disturbing during the initial stages of wearing anisometropic spectacles; it is better tolerated when the glasses are prescribed at a young age. As a general rule, an anisometropia of 3 dioptres can be tolerated; if problems arise, a special evaluation as to the practical applicability is necessary.
Distortion of the image due to peripheral angular magnification narrows the effective visual field.
The prismatic deviation gives rise to double vision in myopes and a ring scotoma in hyperopes.
In anisometropia, the refractive state is different in the two eyes. When corrected with glasses, these give a dissimilar magnification – a condition known as aniseikonia. The illusion created is particularly disturbing during the initial stages of wearing anisometropic spectacles; it is better tolerated when the glasses are prescribed at a young age. As a general rule, an anisometropia of 3 dioptres can be tolerated; if problems arise, a special evaluation as to the practical applicability is necessary.