Collins and Civil Aviation Safety Authority - [2017] AATA 2564

Collins and Civil Aviation Safety Authority [2017] AATA 2564 (6 December 2017)

Division:GENERAL DIVISION
File Number: 2017/0169
Re:Eric Collins
APPLICANT

AndCivil Aviation Safety Authority
RESPONDENT

DECISION

Tribunal:Deputy President Bernard J McCabe
Member D K Grigg

Date:6 December 2017
Place:Brisbane

The Tribunal affirms the decision under review.

...............................[Sgd]......................................

Deputy President Bernard J McCabe

CATCHWORDS

CIVIL AVIATION – conditional class 2 medical certificate – medical standards - examination of medical evidence – imposition of safety pilot condition for public safety – likelihood that applicant would become incapacitated during flight – held applicant does not meet the medical standard relevant at the time – decision of the respondent affirmed

LEGISLATION

Civil Aviation Act 1988
Civil Aviation Safety Regulations 1998

CASES

Bolton v Civil Aviation Safety Authority [2013] AATA 941
Hall and Civil Aviation Safety Authority [2004] AATA 21
Miller and Civil Aviation Safety Authority [2012] AATA 92
Mulholland and Civil Aviation Safety Authority [2007] AATA 1952
Neal v Secretary, Department of Transport (1980) 3 ALD 97
Re Window and Civil Aviation Safety Authority [1999] AATA 525

REASONS FOR DECISION

Deputy President Bernard J McCabe & Member D K Grigg
6 December 2017
BACKGROUND

Mr Collins is a 77-year-old farmer and the owner of a Cessna 182 which he uses for private flying primarily between his home in Tully and a property at Lakeland Downs. He has been flying regularly since 1992. Mr Collins told the Tribunal that he currently flies approximately 50 hours per year primarily between his 2 properties which involves a 1-hour flight time.[1] He also drives freight trucks.
[1] The Tribunal notes that the medical certificate application form completed by Mr Collins on 10 November 2014 indicated that he had flown 60 hours in the previous 6 months, which equates to 120 hours per annum: Exhibit 1, T Documents, T 8, page 16, MRS Online Medical Examination Report completed by Mr Collins on 10 November 2014. The medical certificate application form completed by Mr Collins on 30 November 2015 indicated that he had flown 28 hours in the previous 6 months, which equates to 56 hours per annum: Exhibit 1, T Documents, T 22, page 43, MRS Online Medical Examination Report completed by Mr Collins on 30 November 2015.
In 2007 Mr Collins had surgery to repair his mitral valve[2] and every year he is examined by a cardiac specialist to satisfy the Civil Aviation Safety Authority (“CASA”) that he is medically safe to fly. Mr Collins says he has a full heart check every 12 months and has had no issues and that no one has ever suggested to him that there was an increased chance of a stroke because of the mitral valve repair.
[2] Exhibit 1, T 6, page 12, Report of Dr Jacobs dated 3 October 2014.
On 7 October 2014 Dr Michael O’Rourke, Cardiovascular Specialist, reviewed Mr Collins’ electrocardiogram (“ECG”) results taken on 3 October 2014, and reported that Mr Collins was “doing very well with the biological mitral prosthesis and with his general health” and that “he is fit and well to continue with his flying and with recertification as a pilot from a medical point of view”.[3]
[3] Exhibit 1, T 7, page 14, Report of Dr O’Rourke dated 7 October 2014.
On 20 November 2014, as a result of his satisfactory medical examination, CASA issued Mr Collins with a Class 2 Medical Certificate.[4]
[4] Exhibit 1, T 9, page 22, Letter from CASA to Mr Collins dated 20 November 2014.
Mr Collins told the Tribunal that in or around early 2015 he was having nosebleeds while flying in cold temperatures so he decided to stop taking aspirin (because he thought that was the cause).
Mr Collins said that on 24 June 2015 he had been shopping at a hardware store when he “felt funny”. He said he ended up driving 40km home and decided he better go to his doctor the next day. He said he told his doctor what had happened and the doctor suggested he be checked. Mr Collins decided to be checked in hospital. On 25 June 2015 Mr Collins was admitted to hospital following an episode of hemianopia (a type of vision loss) and confusion.[5] While in hospital an MRI and a CT scan of Mr Collin’s brain, and an ECG, was performed to determine the cause of Mr Collins’ presenting symptoms. The tests demonstrated that “there is quite a large area of abnormal restricted diffusion seen inferiorly in the right occipital lobe consistent with evolving ischaemic infarct” and that Mr Collins had suffered a “acute right occipital ischaemic infarct” (a stroke).[6] Dr Hugh McAlister, Cardiologist, reported that the mitral valve repair was functioning normally and that no cardiac cause for the neurological event was suspected.[7]
[5]        Exhibit 1, T 12, page 27, Report of Dr Armstrong (Intern at the Mater Hospital Pimlico).
[6]        Exhibit 1, T 10, page 24, MRI Report of Dr Withey dated 26 June 2015.
[7]        Exhibit 1, T 11, page 26, Echocardiogram Report of Dr McAlister dated 26 June 2015.
While in hospital Mr Collins was reviewed by Dr Craig Costello, Neurologist. Dr Costello reported that:[8]

(a)the MRI of his brain confirmed the acute ischaemia;
(b)this event happened whilst Mr Collins was on aspirin; and
(c)the event was cryptogenic in origin.
[8] Exhibit 1, T 13, page 29, Report of Dr Costello dated 30 June 2015.

Unknown to Dr Costello at that time, Mr Collins says that he had in fact stopped taking aspirin. Dr Costello said Mr Collins could not drive for one month and should have formal visual fields tests documented prior to returning to driving.[9]
[9] Exhibit 1, T 13, page 29, Report of Dr Costello dated 30 June 2015.
Dr Ian Reddie, Eye Surgeon, conducted a visual field test on Mr Collins on 28 July 2015 and reported that the results showed Mr Collins had left superior quadrantanopia and that it did not represent any great impediment to his holding a private driving license.[10]
[10] Exhibit 1, T 14, page 30, Report of Dr Reddie dated 28 July 2015.
Professor O’Rourke reviewed Mr Collins again on 2 October 2015. Mr Collins told Professor O’Rourke that he was “adamant” that the stroke occurred when he was not taking aspirin. Professor O’Rourke reported that Mr Collins had no symptoms or signs relevant to his cardiovascular system and that he remained very fit and active and that he would be happy for him to maintain his pilot’s licence but “from a neurological point of view, Eric may be best waiting for 12 months from the date of his occipital infarct before he flies alone again”.[11]
[11] Exhibit 1, T 18, page 38, Report of Professor O'Rourke dated 2 October 2015.
On 23 October 2015 Dr Costello reported that Mr Collins had fully recovered from his stroke, had no abnormality in his visual fields and that he was continuing on his appropriate post-stroke therapy medication. Dr Costello notes that he was now aware that Mr Collins was not on aspirin at the time of his stroke and that Mr Collins had ceased taking aspirin when he was travelling in cold climates. In Dr Costello’s opinion, the risk of Mr Collins having a recurrent stroke was low, given Mr Collins was 3 months post his stroke and that he had remained on his post-stroke medications. Dr Costello reported that if Mr Collins maintains strict compliance with his medication he should be able to return to flying his private plane but that the final certification of this will be up to his Designated Aviation Medical Examiner (“DAME”) as per CASA guidelines.[12]
[12] Exhibit 1, T 20, page 40, Report of Dr Costello dated 23 October 2015.
Mr Collins told the Tribunal that after his stroke he was prescribed a different medication, not aspirin, which softens the arteries rather than just thinning the blood. He says he only needs to be medically managed by a general practitioner, everything is stable, he only needs specialised review for the purposes of CASA licensing, and that all he has to do for his conditions is take the medication.
On 30 October 2015 Mr Collins applied for a renewal of his Aviation Medical Certificate Class 2 License.[13] In his application, Mr Collins reported to CASA that he had ceased taking aspirin and that he had a cerebellar infarct in June 2015 which was completely resolved without functional loss.[14]
[13] Exhibit 1, T 21, page 41, Application for Aviation Medical Certificate Declaration dated 20 October 2015.
[14] Exhibit 1, T 22, pages 42 – 48, MRS Online – Medical Examination Report completed by Mr Collins dated
30 November 2015.
Upon receipt of Mr Collins’ Aviation Medical Certificate renewal application, CASA determined that, as a result of his stroke, Mr Collin’s application required a complex case management review (“CCMR”).[15]
[15] Exhibit 1, T 24, page 52, Letter from CASA to Mr Collins dated 7 January 2016.
On 6 January 2016 the CCMR considered Mr Collins’ medical reports and the scientific literature regarding the frequency of stroke recurrence after cryptogenic strokes and decided that the risk of a recurrent stroke was unacceptable.[16] As a result of the CCMR, CASA determined that because of his condition (i.e. occipital ischaemic stroke (cryptogenic type)) Mr Collins did not meet the medical standards set out in Table 67.155 of the Civil Aviation Safety Regulations 1998 (“CASR”).[17] In CASA’s opinion, Mr Collins’ condition presented an unacceptable risk of in-flight incapacitation because there was increased risk of stroke recurrence and post-stroke seizure which could lead to an acute or subtle in-flight incapacitation. CASA said it would consider reviewing the risk assessment after 12 months post the date of the stroke.[18]
[16]       Exhibit 1, T 23, pages 49 – 51, Complex Case Management Report dated 6 January 2016.
[17]       Exhibit 1, T 25, page 53, Letter from CASA to Mr Collins dated 13 January 2016.
[18]       Exhibit 1, T 25, pages 53 – 55, Letter from CASA to Mr Collins dated 13 January 2016.
Mr Collins advised CASA that he accepted CASA’s decision and would reapply when the 12 month mandatory period had expired.[19] CASA advised Mr Collins that after the completion of the 12 month grounding period he would need to undertake a new medical certificate application examination and provide a report from his neurologist and cardiologist.[20]
[19] Exhibit 1, T 26, page 56, Letter from Mr Collins to CASA dated 20 January 2016.
[20] Exhibit 1, T 27, pages 57 – 58, Letter from CASA to Mr Collins dated 3 February 2016.
Formal notice of CASA’s decision to refuse to issue Mr Collins with the Aviation Class 2 Medical Certificate was provided on 10 February 2016.[21]
[21] Exhibit 1, T 28, pages 59 – 61, Letter from CASA to Mr Collins dated 10 February 2016.
On 20 June 2016 Dr Costello completed Mr Collins’ 12 month review and reported that:[22]

(a)since the stroke, Mr Collins had not had any further clinical neurological deficits;
(b)the prognosis for recurrent stroke is highest in the first year and his current risk of stroke, estimated by a variety of risk calculators, was found to be 5% over the next 4 years and 10% over the next 10 years, which is lower than the average of 18% for his age group over 10 years;
(c)Mr Collins’ risk of post stroke epilepsy was highest in the first year and is typically quoted between 5 and 9% in total; and
(d)if Mr Collins has ongoing vascular risk factor monitoring and management there would be no requirement for any further input from Dr Costello unless required by CASA.
[22] Exhibit 1, T 29, pages 62 – 63, Report of Dr Costello dated 20 June 2016.

On the 17 October 2016, 15 months after his stroke, Mr Collins was reviewed by Dr Costello again. Dr Costello reported that:[23]

(a)Mr Collins had not had any new neurological symptoms and remains asymptomatic;
(b)Mr Collins was continuing his medication; and
(c)there was no change in Mr Collins’ risk level, since his review in June 2016.
[23] Exhibit 1, T 33, page 71, Report of Dr Costello dated 17 October 2016.

On 21 October 2016 Professor O’Rourke reported that Mr Collins had completely recovered from his stroke and that the episode occurred after he stopped his antiplatelet therapy (aspirin) and that, from a cardiological viewpoint, he was fit to have his flying licence renewed.[24]
[24] Exhibit 1, T 34, page 72, Report of Professor O'Rourke dated 21 October 2016.
On 24 October 2016 Mr Collins had a vision assessment by Dr Mark Chiang, Opthamologist, which showed “left superior quadrantanopia secondary to right occipital stroke”. Dr Chiang reported that there was no problem with Mr Collins flying from a vision point of view.[25]
[25] Exhibit 1, T 35, page 73, Report of Dr Mark Chiang dated 24 October 2016.
On 4 November 2016 Mr Collins applied to CASA again for an Aviation Medical Certificate Class 2.[26]
[26] Exhibit 1, T 38, page 93, Application for Aviation Medical Certificate Declaration dated 4 November 2016.
On 7 November 2016 CASA proposed to issue Mr Collins with a Class 2 Medical Certificate subject to the condition that “the holder to fly with safety pilot only” (“Safety Pilot Condition”) on the grounds that Mr Collins did not meet the applicable medical standards, as set out in Table 67.155, due to the risk of recurrent stroke or post stroke seizure.[27] The requirements of the Safety Pilot Condition are that the aircraft flown by Mr Collins must be configured with side-by-side seating in the cockpit and the aircraft must have a full set of dual flying controls.[28]
[27] Exhibit 1, T 39, pages 94 – 95, Letter from Doctor Mike Seah, Senior Aviation Medical Officer at CASA, to Mr Collins dated 7 November 2016. Pursuant to CASR 67.195, a person who does not meet the relevant medical standard can be issued a certificate to exercise the privileges of their licenses subject to any condition considered necessary by CASA.
[28] Exhibit 1, T 39, page 97, Requirements of a Co-Pilot and/or Safety Pilot Condition on a Medical Certificate.
On 18 November 2016 Mr Collins lodged an objection to CASA’s decision to impose the Safety Pilot Condition.[29]
[29] Exhibit 1, T 41, page 99, Letter from Mr Collins to Dr Seah, CASA, dated 18 November 2016.
Upon receipt of Mr Collins’ objection CASA determined that his application required a CCMR.[30]
[30] Exhibit 1, T 44, page 102, Letter from CASA to Mr Collins dated 7 December 2016.
On 7 December 2016 the CCMR considered Mr Collins medical reports and the scientific literature regarding the frequency of stroke recurrence after cryptogenic strokes and agreed with the CASA proposal to impose the Safety Pilot Condition on Mr Collins’ Aviation Medical Certificate Class 2 due to the increased risk of cardiovascular accident recurrence.[31] Dr Mike Seah, Senior Aviation Medical Officer at CASA, then wrote to Mr Collins and explained that, while his medical evidence supported his application for a Class 2 Medical Certificate, in accordance with CASA’s clinical guidelines[32] the indicative outcomes for a medical certificate following a stroke state:[33]
o   Applicants with residual impairment, unacceptable current risks and/or risk of myocardial infarction may not meet the required standard for medical certification
o   If a certificate can be issued, permanent annual requirement cerebrovascular and cardiovascular risk assessment may be required
o   If the certificate can be issued, permanent Multi-Crew (Class I) or Safety Pilot (Class 2) restriction may be required
[31]       Exhibit 1, T 45, pages 104-108, CCMR dated 7 December 2016.
[32]              Exhibit 1, T 46, pages 109 – 110, Letter from Dr Seah to Mr Collins dated 7 December 2016.

In Dr Seah’s opinion, based on the medical reports:

(a)Mr Collins had a confirmed ischaemic stroke/cerebrovascular accident;
(b)Mr Collins still has a visual field defect, quadrantanopia, as a result of the death of brain tissue affected by the stroke; and
(c)there was an increased risk of further stroke or cardiac events particular with increasing age; and, therefore

Mr Collins Class 2 Medical Certificate should have the Safety Pilot Condition.

On 14 December 2016 CASA decided to issue Mr Collins with a Class 2 Medical Certificate with the Safety Pilot Condition (“CASA Decision”).[34]
[34] Exhibit 1, T 48 and T 49, pages 112-117, Letter from CASA to Mr Collins re issue of Medical Certificate and Medical Certificate.
On 9 January 2017 Mr Collins applied for a review of the CASA Decision by this Tribunal. Mr Collins submits that the Safety Pilot Condition should not have been imposed because his medical condition and prognosis, including the risk for a future cerebrovascular accident, was not high enough to make the Safety Pilot Condition necessary to preserve the safety of air navigation.[35]
[35] Exhibit 1, T 1, pages 1-2, Application for Review dated 9 January 2017.
A refusal by CASA to grant a certificate is a reviewable decision and an application may be made to the Tribunal for review.[36] The Tribunal has jurisdiction to review the CASA Decision pursuant to section 25 of the Administrative Appeals Tribunal Act.
[36] Sections 31(1)(b) and 31(2), CA Act.

LEGISLATIVE BACKGROUND

CASA is obliged, by virtue of section 9A of the Civil Aviation Act 1988 (Cth) (“CA Act”), to regard the safety of air navigation as the most important consideration in the exercise of its powers and the performance of functions. The Tribunal is under the same obligation given it stands in the shoes of CASA.
Pursuant to the CA Act, a person must not perform any duty that is essential to the operation of an Australian aircraft during flight times if the person does not hold a current “civil aviation authorisation” that authorises the performance of that duty.[37] A “civil aviation authorisation” is defined in section 3(1) of the CA Act to include a certificate under the regulations and includes a medical certificate.
[37] Section 20AB(1), CA Act.
A person holding a civil aviation licence is required to hold a current medical certificate appropriate to the class of licence. Regulation 61.410 of the CASR provides the holders of private pilot licenses, such as Mr Collins, must hold a class 1 or class 2 medical certificate.
Part 67 of the CASR governs the issuing of medical certificates and regulation 11.056 allows the issue of a medical certificate subject to “any condition [such as the Safety Pilot Condition] that CASA is satisfied is necessary in the interests of the safety of air navigation”.
Pursuant to the provisions of regulation 67.180(1) of the CASR, CASA must issue a medical certificate to an applicant who meets the requirements of regulation 67.180(2).
Relevantly here, pursuant to regulation 67.180, in order for a medical certificate to be issued Mr Collins must meet the “relevant medical standard”, or, to the extent to which the applicant does not meet that standard, is not “likely to endanger the safety of air navigation”.[38]
[38] Regulation 67.180(2)(e), CASR.
The relevant medical standard for a Class 2 Medical Certificate is Medical Standard 2 which is the medical standard set out in Table 67.155 of the CASR.[39] Table 67.155 provides relevantly as follows:
[39] Regulation 67.010, CASR.

Item	Criterion
Abnormalities, disabilities and functional capacity
2.1	Has no safety-relevant condition of any of the following kinds that produces any degree of functional incapacity or a risk of incapacitation: (a) an abnormality; (b) a disability or disease (active or latent); (c) an injury; (d) a sequela of an accident or a surgical operation
2.2	Has no physical conditions or limitations that are safety-relevant
Nervous system
2.7	Has no established medical history or clinical diagnosis of: (a) a safety-relevant disease of the nervous system; or (b) epilepsy; or (c) a disturbance of consciousness for which there is no satisfactory medical explanation and which may recur

Regulation 67.015 of the CASR provides that a medically significant condition is “safety-relevant” if it “reduces, or is likely to reduce, the ability of someone who has it to exercise a privilege conferred or to be conferred, or perform a duty imposed or to be imposed, by a licence that he or she holds or has applied for”.
Regulation 67.010 of the CASR defines medically significant condition as including, relevantly:
(a) any of the following (no matter how minor):
(i) any illness or injury;
(ii) any bodily infirmity, defect or incapacity;
(iii) any mental infirmity, defect or incapacity;
(iv) any sequela of an illness, injury, infirmity, defect or incapacity mentioned in subparagraph (i), (ii) or (iii)
(our emphasis)

ISSUES FOR THE TRIBUNAL

The issues for determination by the Tribunal are:

(a)does Mr Collins meet the medical standard set out in Table 67.155 of the CASR; if no,
(b)is the extent to which Mr Collins fails to meet the relevant medical standard “likely to endanger the safety of air navigation” within regulation 67.180(2)(e)(ii) of the CASR; and, if yes,
(c)can any conditions be imposed under regulation 11.056 of the CASR which would ameliorate the threat to the safety of air navigation.

DOES MR COLLINS HAVE AN ESTABLISHED MEDICAL HISTORY OR CLINICAL
DIAGNOSIS OF A SAFETY-RELEVANT DISEASE OF THE NERVOUS SYSTEM:
ITEM 2.7(a), REGULATION 67.155

To satisfy Item 2.7(a) of Medical Standard 2, which is relevant here, Mr Collins must have “no established medical history”, or “clinical diagnosis”, of “a safety-relevant disease of the nervous system”.
According to CASA, Mr Collins does have an established medical history of right occipital stroke with neurological deficit and has a safety relevant condition as per item 2.7 of Table 67.155.[40]
[40] CASA’s Statement of Facts and Contentions dated 1 June 2017, para 25; Exhibit 7, Statement of Dr Seah dated 1 June 2017.
Mr Collins accepts that a stroke is a safety relevant disease of the nervous system and therefore satisfies part 2.7(a) of Table 67.155.[41] However, Mr Collins argues that because he:

(a)presently does not have a stroke he does not have a present clinical diagnosis; and
(b)has only had one occurrence of stroke, this does not qualify as an “established medical history”.[42] Mr Collins supplied no authority for this submission.
[41] Closing Submissions of the Applicant dated 19 October 2017, para 9.
[42] Closing Submissions of the Applicant dated 19 October 2017, paras 9-14.

However, there is Full Federal Court authority, in Neal v Secretary, Department of Transport (1980) 3 ALD 97 (“Neal”), which specifically addressed what constitutes an “established medical history” in the context of the Air Navigation Regulations (which were in force prior to the establishment of the Civil Aviation Safety Authority and the predecessor to the CASR). In Neal one of the issues was whether an applicant for a pilot licence had an “established medical history or clinical diagnosis” of psychosis when he had had only one episode.[43] The applicant argued, as Mr Collins does here, that an established medical history meant an established history of more than one episode. Franki J held (at 101) that the expression “established medical history” does not require a series of incidents. Lockhart J held (at 104):[44]
In my opinion the expression “established medical history” means a medical history which is proved, established or confirmed. There is no necessity for a number or series of episodes or events to occur before there is an “established medical history”. Nor did I see any warrant for requiring a series of episodes or incidents before there could be said to be “a psychosis”. These conclusions are reinforced when it is remembered that the purpose of the medical standards prescribed by the Orders is to require minimum standards of health of persons seeking a licence to fly aircraft. It is not only the safety of the pilot that attracts the concern of the Government; but the safety of other persons flying aircraft or otherwise affected by the movement of aircraft.
The expression…“established medical history” …[is] not [a] mere term… of art. [it]…must have a fixed meaning and not one that varies according to the facts of a given case. What constitutes an established medical history of a particular patient or a particular psychosis may, of course, be a matter for evidence; but the meaning of those expressions is not variable.
[43] Paragraph 3.3 of the Physical Standards set out in section 47.1 of the Air Navigation Orders.
[44] See also Sheppard J, (1980) 3 ALD 97, at 109.
Accordingly, the fact that Mr Collins has had one stroke means he has an established medical history of a safety relevant disease of the nervous system and therefore does not meet the medical standard in Item 2.7 of Table 67.155. It is therefore necessary for the Tribunal to consider whether the extent to which Mr Collins fails to meet that standard is likely to endanger the safety of air navigation.
Given that a significant part of the hearing, and Mr Collins’ contentions, relate to whether Mr Collins meets the medical standard in Item 2.1 of Table 67.155, the Tribunal will also consider whether Mr Collins also fails to meet the medical standard in Item 2.1 of Table 67.155.

DOES MR COLLINS HAVE A CONDITION: ITEM 2.1, REGULATION 67.155
What is a “condition”?

The term “condition” is not defined in the CASR.
However, as noted by Deputy President PE Hack SC in Bolton v Civil Aviation Safety Authority [2013] AATA 941 (“Bolton”), at [28]:
Given that "safety-relevant" is defined in reg 67.015 of the CASR by reference to "a medically significant condition" it must be used in the sense of a state of health.
In Bolton the Tribunal determined that while Mr Bolton had a risk of a condition, he did not presently have a relevant condition.[45] Mr Collins submits, relying on Bolton, that in order to satisfy Item 2.1 of Table 67.155, he must have a presently known condition, not the prospect of having one in the future.[46]
[45] [2013] AATA 941, at [28].
[46] Closing Submissions of the Applicant dated 19 October 2017, para 22.
Mr Collins accepts that he had a condition (a stroke) in the past, but says he does not presently have a condition and therefore it is not safety-relevant.[47]
[47] Closing Submissions of the Applicant dated 19 October 2017, paras 19-24.
Mr Collins contends that there is no condition and that, as in Miller and Civil Aviation Safety Authority [2012] AATA 92, there is no sequela. In Miller the applicant had a haemorrhagic cerebrovascular accident (stroke) and the concern was the residual effect and that the applicant might have neuropsychological issues. The Tribunal granted Mr Miller’s licence on the condition he undertake a flight test to satisfy an instructor that to the extent there are any residual effects they did not impair his capacity to fly. The Tribunal said:
[at 12]: The fact that Mr Miller had a haemorrhagic cerebro-vascular accident or, as it is commonly referred to, a stroke, clearly indicates he had a medically significant condition whether or not there is a sequela to his injury. However, all of the medical reports before us indicate that Mr Miller has made a very good recovery following his stroke and therefore the injury, by itself, can no longer be regarded as being safety-relevant. The only issue is whether he experiences a sequela of his injury in the form of cognitive deficits; and, if so, whether that sequela is safety-relevant.
CASA contends that Mr Collins does presently have a safety-relevant condition (a visual field deficit) and that he does not meet the requisite medical standard and therefore the imposition of the Safety Pilot Condition is appropriate.[48]
[48] Exhibit 1, T46, page 109, Letter from CASA to Mr Collins dated 7 December 2016.
Four medical practitioners gave evidence both by way of report and oral evidence during the hearing:

(a)Dr Cameron, Neurologist, with a Diploma in Aviation Medicine;
(b)Dr Todman, Neurologist, Fellow at the Mayo Clinic, Fellow of the American Academy of Neurology and visiting consultant at Greenslopes Hospital (where he helped develop Brisbane’s first acute stroke unit);
(c)Professor Somerville, Consultant Neurologist specialising in epilepsy, Chair of the Driving Committee of the Epileptic Society and Association of Australian and New Zealand Neurologists; and
(d)Dr Seah, Senior Medical Officer at CASA, who made the CASA Decision.
Medical Evidence – Does Mr Collins have a condition?
Dr Cameron

According to Dr Cameron, Mr Collins had a cerebral infarct (a stroke), as indicated by an MRI, which is a cerebrovascular disease.[49]
[49] Exhibit 2, Report of Dr Cameron dated 9 March 2017; Exhibit 3, Report of Dr Cameron dated 22 May 2017.
Dr Cameron explained to the Tribunal that an ischaemic stroke “can be caused by a blood clot or embolism (blocked blood vessel)” and that an “infarct” means a “lack of blood supply to portion of brain which dies which is what you can see in the MRI”.
Dr Cameron said the cause of Mr Collins’ stroke was unknown and explained to the Tribunal that:
The problem here is that something dislodged from his heart and jammed the artery…it may have come from the mitral valve or the aorta valve. Here a bit of muck, platelets or thrombis has dislodged between left side of heart and jammed – may have come from heart valve or aortic valve or somewhere… [Mr Collins] might have arterial disease in his carotid artery
Dr Cameron accepted that, as per Dr O’Rourke’s assessment,[50] one of the possible causes of the stroke was that Mr Collins stopped taking aspirin. However, Dr Cameron went to say that the clot “may not have come from the mitral valve and may have come from anywhere in his arterial system”.

Dr Todman
[50] Exhibit 1, T 18, page 38, Report of Professor O'Rourke dated 2 October 2015.

In his report of 22 August 2017, Dr Todman said Mr Collins has a past history of a condition, i.e. stroke, but that he does not have a “current condition which would affect his aviation safety”.[51] However, during cross-examination Dr Todman agreed Mr Collins has a cerebrovascular disease as a result of having had a stroke. He then said, “His stroke was a consequence of his cardiac condition, whether he also has cerebrovascular disease has not been determined”. When asked if Mr Collins suffered from a neurological sequela of his stroke by having had quadrantanopia he responded, “On examination he does not have a visual field deficit, but on testing there is a slight gap in his vision, but it is not of any functional consequence”. Dr Todman concluded that the likely cause of Mr Collins’ stroke was related to his heart condition (the mitral valve repair) and temporarily coming off medication.

Professor Somerville
[51] Exhibit 6, Report of Dr Todman dated 22 August 2017.

In Professor Somerville’s report of 24 March 2017, he noted that Mr Collins’ stroke “has resulted in a mild restriction of his visual fields” and that the stroke was not a transient ischaemic attack “as there was a persistent neurological deficit (albeit not clinically significant)”.[52]
[52] Exhibit 4, Report of Dr Somerville dated 24 March 2017.
Professor Somerville told the Tribunal he thought the cause of the stroke was uncertain but said it was “very likely that the stroke resulted from an embolus from the mitral valve” and that ceasing his aspirin medication may have contributed.

Dr Seah

Dr Seah told the Tribunal:

(a)the “condition” is that part of Mr Collins’ brain that produced a stroke;
(b)a stroke is a medically significant condition and resulted in Mr Collins having a neurological defect (i.e. left superior quadrantanopia which is a measurable field defect) as detected by the MRI;
(c)there was also a primary condition, the defective mitral valve, which was repaired; and
(d)the event of the stroke is a condition, and the “dead bit of brain” is also a condition.

Dr Seah agrees with the other medical specialists that the likely cause of the stroke was a clot originating from Mr Collins’ mitral valve repair and the cessation of aspirin but said he cannot be certain.

Conclusion on “condition”

Whether the condition is the stroke, the neurological defect or the mitral valve repair, the expert witnesses all ultimately accepted that Mr Collins has a condition. There is no dispute that Mr Collins now has left superior quadrantanopia and has a mitral valve repair condition that will always be present.
The Tribunal also notes the report of Dr Jacobs dated 3 October 2014. Dr Jacobs had performed various cardiac tests to check the progress of Mr Collin’s mitral valve repair and found that Mr Collins had “very mild mitral incompetence”.
In the circumstances, the Tribunal finds that Mr Collins has a “condition” for purpose of part 2.1 of Table 67.155.

Medical Evidence – Does Mr Collins have a safety relevant condition?

Rule 67.015 of the CASR provides that a medically significant condition is “safety-relevant” if it “reduces, or is likely to reduce, the ability of someone who has it to exercise a privilege conferred or to be conferred, or perform a duty imposed or to be imposed, by a licence that he or she holds or has applied for”.
In Re Window and Civil Aviation Safety Authority [1999] AATA 525 (“Re Window”) Deputy President Forgie said at paragraph 60:
"Having regard to the need to protect public safety while having regard to a person's entitlement to pursue his or her ambitions, we consider that the word "likely" means a "substantial or real and not a remote chance". That is not a matter which can be assessed on statistical likelihood and certainly does not mean "more likely than not", "odds on" or "a more than 50% chance of a thing happening". To adopt those latter three meanings would, in our view, be to place too little weight on the protection of public safety and too much on an individual's entitlements
In Hall and Civil Aviation Safety Authority [2004] AATA 21 (“Hall”) Deputy President RP Handley said at paragraph 45:
"As the Tribunal stated in Re Windows (supra), the assessment of what is "likely" cannot be based on statistical likelihood. In this context, it is a matter of weighing up the requirements of air safety with the applicant's interest in the safe exercise of the privileges and performance of the duties associated with holding a private pilot's licence…When issues of air safety are under consideration, a small risk may be sufficient to trigger the need to take appropriate action to address the risk. This was the case here"
The CASR do not specifically prescribe any particular level of risk. The Tribunal noted this in Mulholland and Civil Aviation Safety Authority [2007] AATA 1952, and, after referring to Re Window and Hall, said:
[65]Whether Mr Mulholland has a high risk or a low risk of losing consciousness while flying an aircraft is simply irrelevant. The fact is that he has a risk of incapacitation which is significantly different to the remainder of the aviator population who do not suffer from syncope or any other safety-relevant medical condition. In our view the risk of incapacitation is real and not an imaginable or fanciful risk nor is it a remote risk.
Mr Ribbans, Counsel for Mr Collins, conceded that the consequence of a stroke inflight would have a catastrophic result and the fact of stroke would be a safety-relevant condition, however he submits that Mr Collins only has a risk. Therefore,
Mr Collins submits, if the “risk of a stroke is the condition” you can take into account the risk of it occurring while inflight. Mr Collins says it is at the low end of the range.
To determine this question involves making an assessment of the risk. Is the risk that Mr Collins will have a recurrent stroke real or remote?

The “1% Rule”

There is a generally accepted guideline in international aviation that a 1% annualized risk of incapacitation is the acceptable level of risk. This rule is set out and explained in the International Civil Aviation Organisation (ICAO) Manual of Civil Aviation Medicine. ICAO is a United Nations agency established in 1944 which governs the Convention on International Civil Aviation, the Chicago Convention, of which Australia is a Member State.
Article 37 of the Chicago Convention provides that:
Each contracting State undertakes to collaborate in securing the highest practicable degree of uniformity in regulations, standards, procedures, and organization in relation to aircraft, personnel, airways and auxiliary services in all matters in which such uniformity will facilitate and improve air navigation.
To this end the International Civil Aviation Organization shall adopt and amend from time to time, as may be necessary, international standards and recommended practices and procedures dealing with:
…
(d) Licensing of operating … personnel;
…
and such other matters concerned with the safety, regularity, and efficiency of air navigation as may from time to time appear appropriate
Dr Seah explained that:

(a)the 1% rule is a measure derived from simulation studies conducted in 1984 by the UK Cardiology Association as a tool to measure risk and is an estimate measure against which regulators calculate risk;
(b)the 1984 studies found that 1 in 400 incidents resulted in a theoretical simulated crash and the pessimistic view was to round that down to 1 and 100;
(c)other than the 1% rule there is no other standard against which to measure risk;
(d)CASA allows for a 2% annualised risk of incapacitation, rather than 1%, for Class 2 licenses because of the different profile of flying, namely private and non-commercial;
(e)The 2% risk guideline takes into account the number of flying hours in a year.

Dr Cameron agreed, on questioning, that the 1% rule is not inflexible but noted that while other limits, such as 2% have been suggested, the 1% rule has been accepted around the world. He explained that the 1% rule is a guideline and opined that “if there were no guidelines you would have different doctors coming up with different conclusions about who could fly.”
Based on the evidence above, the Tribunal sees no reason why it should abandon the 1% rule, or 2% rule as adopted by CASA as a guideline in cases concerning Class 2 Medical Certificates. In any event, as was made clear in Mulholland, there is no 1% rule. What is necessary is that there is a real, not remote risk. However, the internationally accepted guideline can play a useful, if not critical, exercise in assessing risk and in ensuring consistency in decision making concerning air navigation safety.
Further, pursuant to section 11 of the CA Act, CASA must perform its functions in a manner consistent with the obligations of Australia under the Chicago Convention.
The Tribunal considers that the “1% rule” or 2% rule used by CASA for Class 2 Medical Certificates, which has been accepted by this Tribunal previously,[53] is a useful guide when making assessments of what is “likely to endanger the safety of air navigation” and conforms with CASA’s overarching obligation to “regard the safety of air navigation as the most important consideration”.
[53] See Hazelton and Civil Aviation Safety Authority [2010] AATA 693; Daw and Civil Aviation Safety Authority [2015] AATA 1002.

Medical Evidence
Dr Cameron’s Assessment of Risk

On 9 March 2017 Dr Cameron provided an assessment of Mr Collins based on the available medical documents. In Dr Cameron’s opinion, due to Mr Collins’ cardiovascular accident:[54]

(a)the risk of further stroke over the next 4 years is elevated compared to that of the general population;
(b)there was an increased risk of developing seizure activity and epilepsy over the next 5 years; and
(c)the risk was above the 1% per annum accepted to hold the flying license.

[54] Exhibit 2, Report of Dr Cameron dated 9 March 2017.

On 22 May 2017 Dr Cameron provided a further report and said the studies indicate that the annual risk of a recurrent cerebrovascular event was 4% which is above the 1% accepted risk.[55]
[55] Exhibit 3, Report of Dr Cameron dated 22 May 2017.
In forming his opinion Dr Cameron referred to various studies in the medical literature which have shown an increased risk of seizure activity following stroke. Dr Cameron explained that:

(a)the literature considered involve long term studies of a variety of people and shows the risk of recurrent stroke following an initial event;
(b)the studies deal with specific events such as CVA and the risk of recurrence, the sample sizes are large but confined;
(c)in the Hankey (1998) study the age group of the study at which the first stroke occurred was 75 to 84. In his opinion the Hankey study was the “best study” and shows the risk of further strokes in Mr Collins’ age group, and that Hankey is frequently quoted in neurology;
(d)Hankey found that if someone has had a stroke, then over the next 5 years they have a 1 in 6 chance of having another one compared to the general population, (which Dr Cameron says is quite high) and that “a significant risk factor for recurrent stroke was the age at which the first stroke occurred between 75 and 84 years of age which appears to be significant here”;[56]
(e)the So El et al (1996) study showed a high incidence of seizure activity following a stroke;
(f)the Burn (1997) study (which Dr Cameron says is a well-used study throughout neurology) showed that there is an increased risk of seizure over the following 5 years of around 4.2% and that haemorrhagic strokes had a greater risk or recurring than embolic strokes;
(g)according to the studies the annualised risk of a recurrent stroke is 2 – 4% over 5 years.
(h)he had never seen any study which says there is no risk of a further stroke after an initial stroke event. The risk is highest in the first few years then drops;

“all studies say there is a risk but some say the risk is high and it is less significant in others. But all the studies show a higher risk. His treating neurologist, Dr Costello, also gave him increased risk (5% over 4 years which is approximately 1.25% per year, higher in first years)”.
[56] Exhibit 2, Report of Dr Cameron dated 9 March 2017.

Regarding the risk of Mr Collins having a recurring stroke Dr Cameron said:

(a)Even before the stroke Mr Collins was at a risk of a stroke because of his mitral valve repair and that whilst taking aspirin would have reduced the risk, it would not have taken him back to the risk of that of a normal person;
(b)Mr Collins did not have a lot of usual risk factors, such as smoking, obesity and excessive alcohol use, and that the risk is the artificial valve which will not go away;
(c)in his opinion the existence of the previous embolic stroke and the mitral valve replacement increases the risk of Mr Collins having a recurrent stroke and means he is at a much higher risk of having a recurring stroke than people who do not have Mr Collins’ history;
(d)Mr Collins’ annualised risk of having a further stroke is around 4%, certainly way above the 1% rule;[57]
(e)the problem is that Mr Collins is 77 years old, and according to Hankey, the annual risk for that age group is around 16% i.e. a 1 in 6 risk of having further event over next 5 years (and he has had 1 event already) which is above what CASA accepts, and you “don’t want this in aviation”;
(f)studies show the risk is 2-4%;
(g)the risk can be reduced by taking anti-coagulant medication but because Mr Collins had had a mitral valve repair he was at risk of having a stroke. The risk would only be reduced, not completely ameliorated, and would not be reduced to the risk of a normal person with a normal heart valve. Even taking his medication Mr Collins is still above the 1%;
(h)he has never seen an article that someone with a mitral valve replacement is never at risk of having another stroke.
[57] Exhibit 3, Report of Dr Cameron dated 22 May 2017.

In relation to the other medical opinions provided, Dr Cameron said:

(a)Regarding Dr Costello’s report where he said the risk of a further stroke was lower than the average of 18% for the Mr Collins’ age group, Dr Costello neglected the fact that Mr Collins has already had a stroke and was quoting populations who had not had an incident of stroke;
(b)Professor Somerville is an epileptologist, not a specialist in strokes, and therefore his opinion should be given less weight;
(c)When Professor Somerville expressed the view that, if Mr Collins experienced a further stroke it would probably have same mechanism as the first, “he means an embolic disturbance from the heart”;
(d)He disagrees with Professor Somerville that risk is not such as to disqualify from flying. He respects his opinion on epilepsy, but says he has no formal training in aviation to understand what the 1% rule is about;
(e)Dr Todman did not provide any reference to support his assumptions and he did not believe there are any studies which support Dr Todman’s view that Mr Collins’ risk of stroke, given the lapse of time, is the same as that of the general population.

Dr Cameron was asked about CHA₂DS₂-VASc Score for Atrial Fibrillation Stroke Risk (a tool used to assess coronary artery risk) and when asked if Mr Collins had a risk of 3% would that be too high? Dr Cameron said “Yes”.
In summary, in Dr Cameron’s opinion:

(a)given his age and the fact of a previous stroke, he has a 1 in 6 chance of having a further stroke;
(b)“in my opinion, based on papers, reports and experience, Mr Collins is above accepted aviation rule. He is above 1%, probably 4%, can’t say how far above 1% but probably 4%”; and
(c)he would be worried if his daughter was flying with Mr Collins.
Dr Todman’s Assessment of Risk

Dr Todman provided two reports in which he reported that in his opinion:[58]

(a)the risk of Mr Collins having a recurrent stroke was low and similar to persons of the same age; and
(b)the future stroke risk was 2 – 3% over the next 4 years.
[58] Exhibit 5, Report of Dr Todman dated 7 March 2017; Exhibit 6, Report of Dr Todman dated 22 August 2017.

Dr Todman told the Tribunal:

(a)the main risk is Mr Collins’ heart valve surgery as Mr Collins does not have the other risk factors for stroke;
(b)the mitral valve repair gives an elevated risk, but it is a lower risk than if the valve had been replaced;
(c)Mr Collins has a modest increase in risk compared to someone at his age, considering:
(i) the length of time since his stroke;
(ii) the probable cause (ceasing aspirin);
(iii) he has had no further symptoms; and
(iv) he is taking new medication which has a stronger anti-clotting property;
(d)Mr Collins’ annualised risk would be less than 4%, likely to be 1-2%, which is only a modest increase compared to other persons of his age;
(e)his risk is low but not 0% if he is taking the medication;
(f)a previous stroke is a marker of risk factor and Mr Collins is at increased risk of further stroke because he has had a stroke;
(g)age is an independent risk factor and Mr Collins has a higher risk than somebody younger; and
(h)flying is not a risk factor;

Dr Todman said his opinion was based on a global assessment and clinical impression. In Dr Todman’s opinion, reference to the medical literature has its limitations because it is a bundling together of a wide variety of people with a wide variety of causes. Dr Todman is not aware of any paper that looks at risk of someone in Mr Collins’ case who is in a stable condition after mitral valve surgery, comes off aspirin and has a mini stroke. Dr Todman said “analysing the particular circumstances of a person’s case is the most appropriate way to reach a conclusion about a risk. Extrapolation from literature is always imprecise”.
In Dr Todman’s report of 22 August 2017 he reports:[59]
I am in general agreement with Dr Cameron’s reports…the papers that he states regarding stroke prevention are all accurate and pertinent to some degree.
[59] Exhibit 6, Report of Dr Todman dated 22 August 2017.
In summary, Dr Todman said:

(a)Mr Collins’ annualised risk of having a recurrent stroke is likely to be a lot less that 4% and more likely to be 1-2% per annum;
(b)If Mr Collins takes his medication it would reduce the risk but the risk is not zero, “the risk would remain even if he did take the medication”.
Professor Somerville’s Assessment of Risk

At the hearing, Professor Somerville told the Tribunal he has “not undertaken any specialist aviation medicine studies, however, he is Chair of Driving Committee of the Epileptic Society and Assoc. of Aust/NZ Neurologists and issue of fitness to drive is something he deals with a lot and there are a lot of parallel issues with flying.”
On 24 March 2017 Professor Somerville, Consultant Neurologist, provided a report and referred to studies:[60]

(a)undertaken by the American Heart Association and American Stroke Association which indicated a 3-4% risk of recurrent stroke;
(b)by the National Clinical Guidelines for Stroke by the Royal College of Physicians which showed a 26% risk of recurrent stroke over 5 years; and
(c)which showed risk ranges between 5%-10%.
[60] Exhibit 4, Report of Professor Somerville dated 24 March 2017.

Regarding the medical studies referred to by Dr Cameron, Professor Somerville said:

(a)studies are only indicative - they give “ballpark figures” and a range of outcomes;
(b)the van Wick Study (Lancet 2005) indicates that the “annual risk of stroke was about 5% immediately after the first stroke, 1-2% three years after, and 12% over the next 5 years”;
(c)“An assessment of someone’s fitness to fly is different to the assessment of risk of recurrent stroke. To assess Mr Collins’ risk you need to look at the figures from the literature and see if there are features in his case which would imply a higher or lower than usual risk.”;
(d)In Professor Somerville’s opinion, from the studies he considered the more optimistic range is risk of 1-2% and a pessimistic range is around 3-4%. However, he said there is not a lot of difference in ranges from the reliable studies - the figures are very similar. In Professor Somerville’s opinion “it is hard to argue between 2 and 4%”.

Regarding the risk of Mr Collins having a recurring stroke, Professor Somerville said:

(a)taking medication would reduce the risk but he was uncertain to what degree;
(b)Mr Collins had a mild stroke, however that does not mean lower risk of recurrence;
(c)factors that bring about stroke are relevant to the risk of recurrence;
(d)given that it had been 2 years since his stroke, and risk falls with passage of time without seizures, he would “guess probably 1% or something like that”, “1-2% as ballpark”.

Professor Somerville said he was not aware of the validated tool devised by the National Institute for Stroke and Applied Neurosciences at Auckland University and when informed by Ms Swain on behalf of CASA that when using that tool, taking into account someone of Mr Collins’ age and sex with no risk factors, it calculated the risk at > 3% per annum, Professor Somerville said he “can’t argue given the data between 2 and 3%”.
In summary Professor Somerville said “because of the small number of hours exposed to risk, [Mr Collins] would appear to have a very low risk of coming to harm”.
Professor Somerville considered that the 1% rule did not take into account the time a person is exposed to risk. However, during his oral evidence he acknowledged that he was not aware that the rule takes flying time into account.

Dr Seah’s Assessment of Risk

Dr Seah said he holds a fellowship to the Australasian College Of Aerospace Medicine and is qualified to make risk assessments.
At the hearing, Dr Seah explained that when an application comes to CASA, the medical conditions are assessed in accordance with the medical standards in the CASR. If there is doubt or concern, the case is referred to CCMR for a review and recommendation. A risk assessment is made by the CCMR based on medical reports and literature.
Dr Seah agreed that determining whether a condition is safety-relevant involves an assessment of risk and requires assessing an individual’s circumstances.
Dr Seah said when dealing with an applicant who has a history of stroke, CASA primarily looks at the neurological impact of the stroke. The risk of future stroke is a relevant consideration.
In Dr Seah’s opinion the risk of Mr Collins having a recurring stroke cannot be ignored. He told the Tribunal that:

(a)validated risk calculations include factors such as age, sex, blood pressure medication, previous stroke occurrence and that using the validated tool devised by the National Institute for Stroke and Applied Neurosciences at Auckland University the risk for Mr Collins, excluding taking into account whether he was taking any blood pressure medication, was 13.74% in the next 5 years that is 2% annualised;
(b)taking aspirin reduces the risk but it does not ameliorate and there are no means to measure how the risk would be ameliorated by Mr Collins taking his anti-coagulant medication
(c)Regarding the opinions of Dr Todman and Professor Somerville:
(i) he disagrees with Dr Todman and Professor Somerville and says there is no basis for their opinion and notes that they do not provide adequate references to the literature for their assertions;
(ii) randomised controlled trials are the highest level of evidence whereas opinion evidence is the lowest level.

In Dr Seah’s opinion, the opinion of Dr Cameron (of an approximate 4% risk) should be preferred because it is based on the literature and on the available evidence, it is the best information available to assess Mr Collins’ risk.
Dr Seah believes the Safety Pilot Condition is necessary and reasonable. He said the aviation perspective might be different to the medical perspective because there are consequences for aviation safety and CASA must consider the safety of the pilot and the passengers.

CONSIDERATION

Relevance of 1% or 2% rule

In relation to the 1% rule, Mr Collins submits that it is based on studies/tests in relation to commercial pilots. However, as referred to above, CASA has adopted a 2% rule as a guideline in cases concerning Class 2 Medical Certificates and the internationally accepted guideline can play a useful, if not critical, exercise in assessing risk and in ensuring consistency in decision making concerning air navigation safety.
In relation to the studies, opinions and averages on which CASA relies, and previously referred to by Dr Cameron and Professor Somerville, Mr Collins submits they are not accurate when applied to him because he does not have the normal risk factors that other persons considered in those studies may have. However, as CASA submits, randomised controlled trials are the highest level of evidence whereas opinion evidence is the lowest level. Further, there must be some basis upon which a medical opinion on risk can be derived. Dr Cameron’s opinion, and to some extent Professor Somerville’s, were derived and guided by the medical studies. There was no criticism of the methodologies or results of these studies, only the applicability to Mr Collins. Further, there was no in-depth analysis of the studies provided by Mr Collins to justify the Tribunal’s dismissing the relevance of the opinion of the medical experts that were guided by them.
An assessment of risk must be made somehow. The Tribunal agrees with the submission of CASA that the body of evidence from the randomised trial studies provide the best information available to assess Mr Collins’ risk. Dr Todman did not refer to the available literature or provide any real guidance for how he came up with his assessment of risk other than to say it was based on a “global assessment and clinical impression”.
In relation to CASA’s reliance on the medical literature, Mr Collins did not criticize the merits of the studies but rather sought to distinguish his case from those studied. However, as Dr Cameron pointed out, the Hankey study was based on persons in Mr Collins’ age group who had had one previous stroke. All the medical practitioners accepted that the study results were guidelines and that Mr Collins had to be assessed individually, however, the Tribunal sees no foundation in an argument that those studies cannot be considered by the medical experts in arriving at their opinion. It is certainly preferable to an opinion which has not been based on an analysis of the current medical findings. Doctors Cameron, Todman and Professor Somerville all accepted that the studies provide ranges and were, at least to a degree, pertinent to an assessment.

Weight to be given to the opinions of Dr Cameron and Dr Seah

Mr Ribbans contended that because Dr Cameron had not seen Mr Collins in person, his opinion should not be given as much weight as that of Dr Todman and Professor Somerville.[61] Dr Cameron told the Tribunal that while it is always preferable to see the patient, Mr Collins had already been seen by neurologists and had tests already, and that it was “highly improbable he would find something on examination which the other specialists have not found”, and he had everything he needed in order to form an opinion. While in some cases the lack of a physical examination may be relevant to an assessment of the weight to be given to an opinion, in this case the Tribunal does not consider this reduces the weight that should be given to Dr Cameron’s opinion. All the medical opinions have been primarily based on the fact of stroke, the fact of the quadrantanopia, the fact of the mitral valve repair and/or the medical literature, and not on any personal examination of Mr Collins. A consideration of those factors did not require Mr Collins to be examined in person.
[61] Closing Submissions of the Applicant dated 19 October 2017, paras 25-32.
Mr Ribbans also contended that the opinion of Dr Seah is not relevant given that he was the original decision maker and was not a specialist neurologist. The Tribunal accepts that Dr Seah is not a neurologist and, as decision maker at CASA, not impartial. However, his evidence regarding how CASA arrived at his decision is not controversial and his evidence can also be seen as CASA’s submissions in support of its position. The Tribunal will consider Dr Seah’s opinion in that light.

Conclusion on Risk

Mr Collins submits that the risk of a recurring stroke is remote and that the risk of his having a recurrent stroke while flying to and from his own properties is an almost non-existent risk to persons on the ground.
Mr Collins says his stroke was a product of a discrete event, i.e. blood clot from an unidentified cause, which took place during a time when he was not taking aspirin. If he had been taking aspirin he submits there is no greater risk than any other general member of the population. However, that is not borne out by the medical evidence.
The medical experts agreed that:

(a)Mr Collins is always at a risk of a stroke because of his mitral valve repair;
(b)whilst taking aspirin may reduce the risk of a recurrent stroke, it would not take him back to the risk of that of a normal person;
(c)Mr Collins does not have a lot of usual risk factors, such as smoking, obesity and excessive alcohol use;
(d)the existence of the previous embolic stroke and the mitral valve replacement increases the risk of Mr Collins having a recurrent stroke and means he is at a much higher risk of having a recurring stroke than people who do not have Mr Collins’ history;

(e)age is an independent risk factor and Mr Collins has a higher risk than somebody younger; and
(f)the risk is that Mr Collins could have a recurrent stroke at any time even if he is taking anti-coagulants.

While the medical experts varied on whether the percentage of annualised risk was 1%-2%, 2%-3% or 4%, they all, including Dr Todman, agreed Mr Collins is at an increased risk of stroke. Whether it is a 1%, 2%, or 4% risk, is not of statistical significance (as Professor Somerville said).
In the circumstances, remembering CASA’s overarching obligation to regard the safety of air navigation as the most important consideration in the exercise of its powers and the performance of its functions, the Tribunal finds that the extent to which Mr Collins fails to meet the Medical Standard is likely to endanger the safety of air navigation.[62]
[62] CASR 67.180(2)(e)(ii).
The issue to determine is whether any condition, such as the Safety Pilot Condition, can be imposed which would ameliorate the threat to the safety of air navigation.

IMPOSITION OF A SAFETY RELEVANT CONDITION

Mr Collins submitted that his health is better than in other cases where a Safety Pilot Condition has been imposed.
Mr Collins also argued that due to his limited flying time his risk of inflight incapacitation was lower and that this should be taken into account. Mr Collins also suggested that alternative conditions restricting him from having any passenger without a licence other than his wife or restricting his flight paths to less built-up areas would ameliorate the risk.[63]
[63] Closing Submissions dated 19 October 2017, para 52.
However, each case has to be assessed on its own set of circumstances. Mr Collins and CASA accept that a stroke inflight would most likely be a catastrophic and potentially fatal event. The risk of stroke is there, regardless of the number of hours flown or who a potential passenger is.
Dr Cameron told the Tribunal that:

(a)if Mr Collins had another stroke he may have focal issues or convulsing and blanking out which would make him totally incapacitated to fly;
(b)if someone has a stroke:
(i) their alertness and perception can be impaired, yet they may not realise;
(ii) they can become amnesic or inattentive and may not know;
(iii) confusion can also mean they do not know they are impaired;
(c)the initial presentation of a stroke could be subtle;
(d)given Mr Collins said he “felt funny” after the stroke and ended up driving 40km home and decided he better go, constituted dangerous driving.

Dr Todman told the Tribunal that symptoms of stroke are diverse but common symptoms are weakness on one side of the body, loss of vision and slurred speech, all of which would have adverse consequences on a person’s ability to fly an aircraft.
Professor Somerville said if Mr Collins had a stroke he:

(a)could suffer paralysis, numbness, visual impairment and difficulty speaking;
(b)might become paralysed or numb down one side, double vision, incoordination, difficulty speaking or difficulty with vision; and

that, depending on what happened, it may impair his ability to fly an aircraft.

In the circumstances, the Tribunal finds that the Safety Pilot Condition would appear to be the only condition which will ameliorate the risk posed, particularly having regard to CASA’s overarching obligation to regard the safety of air navigation as the most important consideration in the exercise of its powers and the performance of its functions.[64]
[64] Mulholland and Civil Aviation Safety Authority [2007] AATA 1952, at [66]-[67].

DECISION

The Tribunal finds that Mr Collins fails to meet the applicable medical standard and that there is a likelihood that he will endanger the safety of air navigation, and that given that he may have a further CVA and the repercussions of such an event, the imposition of the Safety Pilot Condition to ameliorate that risk is appropriate.
The decision under review is affirmed.

I certify that the preceding 125 (one hundred and twenty-five) paragraphs are a true copy of the reasons for the decision herein of Deputy President Bernard J McCabe and Member D K Grigg

..............................[Sgd].......................................
Associate
Dated: 6 December 2017

Date of hearing: Date last submissions received:	12 October 2017 2 November 2017
Advocate for the Applicant:	Mr Ribbans
Solicitors for the Applicant:	International Aerospace Law & Policy Group
Advocate for Respondent:	Ms Swain, Principal Lawyer Litigation and Enforcement Section, Civil Aviation Safety Authority