Tuesday, 26 November 2019

MOTION SICKNESS CAN KILL…


Most readers will probably be thinking “No it can’t. Don’t be absurd!” I hope so because if not there might not be enough curiosity to encourage you to read on.

Good. You at least have persevered. Absurd it may be but nevertheless, I stand by my statement. Clearly, I haven’t died from motion sickness, or anything else just yet, so I need to tell my story of how motion sickness could have taken, and in fact very nearly took, my life and the life of at least one other. Dramatic enough? A bit too much? Stay with me.

I have had a sulky and slightly green-tinged relationship with motion sickness for as long as I can remember. Ignoring those early queasy rides in the claustrophobic rear seat of my step-father’s Ford Zodiac in the 1960s, weaving and rolling along the windy lanes of the Isle of Wight’s chalk Downs, my first full-on encounter was with mal de mere, zeeziekte or seasickness as the sick-bag provided helpfully explained in 3 languages.

Actually, before we cast into historic oblivion those memories of mildly nauseous, pre-seatbelt era jaunts across the Island, I should perhaps explain the purpose of our journeys. If indeed it really qualifies as a ‘purpose’. My step-father was a curious man, in every aspect of that adjective. Confining our attention to the sort of curiosity that is said to kill cats or to elongate the nose of the elephant’s child (check out Kipling if you are scratching your head), he wanted to know how other people lived.

Obviously, he could visit friends and relations, and note their choice of house, furnishings, garden landscaping, clothes, even partners. But that limited his insatiable curiosity to people he knew and that was far from enough for ‘Jack’. He wanted a much larger sample of the population from which to illustrate his dinner time anecdotes on the habitual idiosyncrasies of our fellow Isle of Wight residents.

Hence, after weekend lunches at our home near the centre of the Island we would head out on a random spoke towards the coastal periphery, in search of new domestic pastures to explore. Mother and step-father in front, brother and occasionally step-sister in the back we would emerge from the driveway on another bizarre quest.

The way it worked was Jack would look for a grand gateway or house sign out in the countryside. I should explain that his curiosity did not extend to how suburban people lived. Once the target was identified he would simply sweep up the drive until we reached the front of whatever house appeared at the end. Handbrake on, engine off he would clamber out (he was a very large curious man) and look about as if a little perplexed.

Eventually an owner or two would appear and ask, “Can I help you?”
“Oh” Jack would reply, “I’m so sorry, we were heading for [insert fictitious location] but must have taken a wrong turn”.
To cut a long, and in my childhood oft repeated, story short, this almost invariably ended with us sipping tea and nibbling cake in the kitchen/parlour/drawing room of the strangers’ house before we kids went to play in the garden with inevitable dogs and the adults had a tour of the property. Curiosity satisfied, at least until next weekend. Now I’ve got that off my chest we really can ignore that first gentle brush with motion sickness and get back to the real thing.

The aforementioned multi-lingual sick-bag was to be found in a cramped inside cabin on the Dutch cruise liner Neu Amsterdam. Mother, brother and I were, for some reason now unclear to me, making our way from Southampton to the Irish port town of Cobh by way of the second leg of the ship’s trans-Atlantic voyage from Rotterdam to New York. Quite why we didn’t take the train and ferry or fly as we had done before I don’t recall.

Ship-board life seemed rather grand until we met an enormous Atlantic swell in the Channel and the great vessel began to sway like an inverted pendulum. Meal services were curtailed, water slopped heavily out of the swimming pools, Mother threw up her false teeth over the ship’s rail and I retreated to the little cabin to wallow in self-pity. Lying in my narrow bunk I was utterly incapacitated by the effects of the ship’s movement and quietly prayed for death; or at least a speedy arrival in Ireland. That’s the thing about motion sickness and me, the instant the motion stops the symptoms disappear. Rather like childbirth (so I’m told) I seem to forget the hours of hell in an instant and become immediately willing to subject myself to a another, similar ‘moving’ experience.

So in part, that is how I came to my next, rather more sustained and significantly more unpleasant, experience with the restless sea. For yet another forgotten purpose, when I finished school I was determined to join Father and brother in the English West Country. As a commercial fisherman. Now with hindsight this can be seen as a questionable choice for someone evidently predisposed to seasickness but with the blithe and blinkered determination of male teenage, I went west. Almost literally, or so it felt.

If you have never experienced the rearing deck of crab fishing boat, tossed on a raging sea, tormented by winds that whip spray from the wave crests, driving it into eyes and ears, as a cold grey dawn rises to the east of some remote place a hundred miles south of the Devon coast, I probably don’t have words adequate to describe it. Seasickness is a psychological malaise as much as a physical one and the torment knew no bounds. In an environment where the men were tough and laughed in the face of adversity, it was an added misery to be the sickly kid barely able to contribute to the task of catching crustaceans and even less able to justify a share of the proceeds from the catch. Especially awkward that as soon as the catch was landed and we hit the pub, I felt fine.

Suffice to say that I have since dabbled in offshore yacht racing (a mix of becalmed boredom and storm-driven chaos), served as an apprentice in the Royal Navy and navigated ships in the Merchant Navy, so there have been plenty of other aquatic experiences that have challenged my semi-circular canals. But none of them can support my assertion that motion sickness can kill. What this catalogue of deeply unpleasant episodes did reveal is that some of us can be ‘desensitised’ from the undesirable effects of the condition. After the first predictably nauseous 24 hours at sea the symptoms would vanish and I could spend the rest of each voyage reading books, eating meals and doing my job just like a real seafarer. Of course, I did begin to suffer from ‘land sickness’ when returning from a long spell at sea but that is another story.

Having learned of my vulnerability to motion sickness, my next adventure was not the obvious choice. I decided that I needed to become a pilot. Not just any pilot but a military pilot. Not just any military pilot but one of the ones who flies jets. The ones who roar around the place at airshows making lots of noise, pulling lots of g-s, before turning on a sixpence and coming back to do it again. It turns out that isn’t all they do either; they spend some time hurtling through the twisting valleys of Wales or chasing each other around the sky in mock dog-fights. Mostly because it’s good fun. Unless you get airsick of course…

I started my flying career on a fairly sedate jet trainer – capable of 300 knots through the air but nevertheless sedate in comparison to what was to come. However, there was a new problem I hadn’t bargained for. I discovered I was a bit of a party animal in what was, to be frank, ‘party town’. A horde of young aspiring fighter pilots all vying for the attention of; well of anyone who would pay them attention. Drinking alcohol appeared to be an essential element of every activity except flying. There was even a beer fridge in the squadron crew room and a polished stainless steel Harvey Wall-banger bucket hanging from a bracket on the wall. I suspect those days have gone.

0700 AM met brief with a raging hangover could be a bit of challenge in itself but a 45 minute general handling sortie of steep turns and stalls, seated cheek-by-jowl next to a vigilant and critical instructor, was a whole new game.
“Feeling OK today Gillespie?”
“Hundred and ten percent Sir! Ready to give it a thrashing.”
Apparently, hangovers are also a form of emetic and I learnt my lesson quickly, after sheepishly carrying a soggy sick bag back to the line office. Motion sickness wasn’t going to kill me just yet.

The rest of the basic flying training went well from what I recall, apart from a 300 knots encounter with a seagull just above the Northamptonshire countryside. With surprising inertia for a bird it peeled open the metal nose of the aircraft, turned itself into mince and obliterated the entire of my windscreen. Fortunately, there was a colleague in the other seat who could still see and safely flew us home.

Non-hangover induced airsickness, the real thing, turned up early in the next phase of training. Very early. With good reason the first scheduled sortie of most flying courses is something of a demo flight; no specific exercises just a chance for the instructor to show how the new aircraft type performs. With far less good reason most instructors seem to interpret this loose sortie plan to mean ‘throw the aeroplane around at the very limits of its performance to see just what the student is made of’. Mercifully, in the new aircraft the student sat in front of the instructor not beside him but it was still tricky to disguise retching and vomiting into a paper bag whilst upside down at 500 knots.

This was the first of a number of unfortunate events and, although we discovered that I was far less prone to sickness when doing the flying myself, it was only a matter of time before lost and curtailed sorties raised a question mark over my career. The doctors tried medication but as I suspected, the tablets were placebos and had no noticeable effect. Turns out you can’t take conventional travel sickness pills and fly jets; who knew? Something about drowsiness.

At some point I remembered the desensitising effects of prolonged exposure to motion at sea, perhaps that could help? Alarmingly, the Doc’s response was to suggest a spell on the centrifuge at the Institute of Aviation Medicine! Kill or cure. That sounded horrific so I hastily proposed an alternative period of daily exposure to flying similar manoeuvres but as a ‘passenger’ in the back seat. Plenty of sorties flew with only one seat occupied so this was viable and eventually the bosses were persuaded to give it a try. The quid pro quo was that I was suspended from training for the duration. Seemed a bit drastic to me but I had no choice – it was that or the centrifuge.

And it worked. I had a bit of a struggle for the first day or so but it didn’t matter because I wasn’t trying to fly as well as vomit. Just like at sea, I soon lost sensitivity to the rolling, spinning, looping and generally hurtling around and within weeks I was allocated a place on the next course. Just with the proviso to ‘keep him flying’. A few months later the course was complete and I was awarded my ‘wings’, now officially a pilot. Albeit one rather prone to motion sickness. Still not dead though.

Predictably, between the advanced flying course and the next phase of tactical weapons training there was a gap in flying. What happens in a gap? I become re-sensitised to motion and the whole thing begins again. This course was designed to take well-trained pilots and teach them how to fight; same plane so not much new there but the exercises were more aggressive, more dynamic, more sickness inducing. One might expect this to have been a course too far for me but contrarily, the worse it got the more determined I became to keep going. And my bosses had spent a lot of time and money on me by then so they had no incentive to let me go.

The solution? Same again: suspended from training, sat in the back, daily flying, short period of struggle then sorted. The time between courses was a bit longer this time so they dreamed up ‘useful’ things for me to do while I waited for the next course to start. I was taught how to aerial tow an air-to-air gunnery target for example. Bearing in mind there were weapons students loosing off live rounds of ammunition a few hundred metres behind my aircraft, hopefully destined for the ‘flag’ target, it wasn’t my favourite option. Rather better was leading the ‘cine weave’ exercise, as the pursuers fought to keep my aircraft in their gun sight as I banked and rolled ahead of them. No live ammo but the collision risk was significant.

I was beginning to enjoy myself and getting very comfortable with the aircraft. One morning I was assigned to fly in the back seat with one of the instructors, on a ‘bounce’ sortie. Two other similar jets had been tasked with a low-level simulated bombing mission, following a route through the Welsh countryside to attack a couple of targets. ‘Low-level’ for a training flight was constrained by a 250 feet minimum separation distance, meaning they had to stay at least 250 feet above the ground and anything attached to the ground. The same rule applied to us and it was our job to find them, ‘attack’ them and stop them hitting their targets.

We knew their planned route, which was very helpful and perhaps slightly unrealistic, and we knew they would be flying at 420 knots, or 7 miles a minute, so we could work out where they would be at any given time. Before take-off the front-seater and I agreed the best spot for our ambush would be in valley to the northeast of the town of Carmarthen. The attack pair set off and after short time we barrelled down the runway, took off and banked steeply out over the Bristol Channel, as we had so many times before.

Things happen fast at 400 plus knots and soon we flashed over the Welsh coast at the Gower Peninsula. No time to admire the view, we had planes to catch! Leaving Carmarthen to our right we banked around the outskirts and dropped down into a valley to the north of the town, perfect cover for our attack. The aircraft did not have a radar altimeter but from experience I judged that we were spot on our minimum separation distance of 250 feet above the valley floor, with trees and fields whipping past on either side. My estimate was later proven to be eerily accurate.

Visibility was a bit misty but as I looked out to our left, I saw the dark angular webbed outline of an electricity pylon, perched on the ridge line above us. Quickly looking to the right, I saw a similar pylon silhouetted against the pale grey sky behind it. Chances were that there was something joining these two together.

I just had time to shout “Pylons!” before something dark flicked past the canopy and our little cockpit world lit up in great blue flash of light. This was followed immediately by the illumination of just about every warning light the instrument panel had, accompanied by a deafening a cacophony of bells and horns. Something clearly wasn’t as it should have been.

The instructor pulled back on the control column sending us almost vertically skywards, gaining precious altitude in case our one engine was damaged. As we shot up, the pilots of our target aircraft just a few miles away had seen the bright flash of light and broke off their mission to investigate. What they saw was our jet trailing a plume of what they thought was smoke and told us on the radio. It later turned out to be a fine mist of hydraulic fluid leaking from the damaged wing but the message had the effect of focusing our attention even more, if that were possible. We discussed whether we would need to eject, and I nervously tightened my straps in anticipation.

But wait a minute, the engine was still running, the aircraft was still flying and it was responding correctly to the controls. Perhaps we weren’t going to die. Thoughts turned to other things.
“We’re going to be in trouble for this”, groaned my colleague.
I was a bit offended by the ‘we’ part but it wasn’t the time to argue. After assessing the damage and finding what bits of the aircraft were still working, we headed to the nearest available military airfield. Miraculously we were soon parked on the runway and clambering out of the cockpit to some very welcome terra firma. It looked as if someone had taken a giant can-opener to our wings.

The subsequent board of enquiry determined that the aircraft had hit and severed the top three cables between the pylons, at 70 degrees of right bank and about 440 knots. The left wing took out the top cable and the right wing took care of the pair below. Clearly, we hadn’t maintained the requisite separation from the cables! Lucky for us, geometry showed that in normal conditions the lowest point of the cables would be 246 feet above the valley floor. The bosses seemed to think that was an acceptable margin of error.

So did I die? No. But it was frighteningly clear that if we had been wings level at impact and any of the cables had struck the cockpit canopy, it would have taken the canopy off and both our heads with it. I understand that’s usually fatal. And was motion sickness to blame? Well I was only in that seat, at that time, flying down that valley because of my recurring airsickness, so I think so, yes… Motion sickness can kill!

Wednesday, 20 November 2019

SEE & AVOID - A SOUND COLLISION AVOIDANCE STRATEGY?


ICAO standards and consequently most regulatory jurisdictions state that pilots have an obligation to be ‘vigilant’ so as to see and avoid other aircraft – here is an example:

US FAA Regulation 14 CFR Part 91.113 (b) states:

…vigilance shall be maintained by each person operating an aircraft so as to see and avoid other aircraft


In many ways this has come to be seen as the last line of defence in collision prevention but we know that it fails. We need to understand why this is – what are the limitations to see and avoid?



Firstly, there are significant physical obstructions to a pilot’s line of sight, in the shape of the aircraft’s own structure. In fact a pilot’s field of view as permitted by the size and shape of the cockpit windows, only constitutes a small portion of the total sphere of airspace around him or her. In some aircraft the wings may also present a further external obstruction to their view. Moving one’s head may help mitigate for things like window posts but nothing will permit observations below, above or behind the aircraft. Pilots must understand that these are effectively blind spots to any see and avoid strategy.



We are well aware from eyesight tests that human vision varies substantially from one person to another. It is also true that an individual’s own visual acuity can vary with time of day, fatigue, light conditions etc. Those of us of a certain age also know that our eyesight deteriorates with the passing years… The likelihood of actually seeing a conflicting aircraft, even if it is within the field of view, is highly dependent upon the visual acuity of the observer and there is no consistent means to predict that.

We also know that the sensitivity of the retina varies across its surface. The point at which the lens focuses the image, the Fovea, is the most sensitive to colour and definition but this diminishes as distance from the Fovea increases. Our peripheral vision, what we see ‘out of the corner of the eye’ is relatively insensitive and is actually best at detecting motion across the arc of vision. This is recognised in the design of road traffic signals, which use not only a change of colour but a change of light source position to attract our attention – rather like the wig-wag lights on taxiways.

Another inherent visual factor is empty field myopia. At rest or in the absence of something to focus on, our eyes focus at approximately half a metre distance. This means that when looking at an empty sky, we may inadvertently be focused much too close and thereby compromise the ability to see another aircraft in the distance. Other effects like dirt on the windscreen can ‘trap’ the focus of the eye. It may be necessary to deliberately choose objects in the distance to draw the focus out to where the targets might be.

Pilots will be familiar with the effects of glare from a low bright sun – it is quite simply impossible to look in that direction let alone search for aircraft. Fighter pilots have always taken advantage of this to attack ‘out of the sun’. To make it worse pilots may be tempted to use sun visors or even charts and newspapers to block out the glare, thereby increasing the area physically blocked from view. Glare may also interact with atmospheric effects like dust, haze, mist and precipitation to increase their effect on the prevailing visibility. Whilst we know that VFR includes 5 kilometres of visibility, this can vary dramatically in different directions with the atmosphere and the light. 



See and avoid may not be so hard if all we had to do was look out of the window. Unfortunately, or perhaps fortunately, pilots have many other things to do and cockpit workload often increases in the same places that traffic density increases. This allows less and less time for looking for aircraft precisely when there may be more to see. As with all cockpit activities pilots must be careful not to become so absorbed with one task as to forget to carry out another task, such as looking out.


There are a number of techniques recommended for more effective visual scanning. As well as moving the head, pilots can divide the field of view up into segments and scan each in turn in a systematic fashion. In the case of 2 pilots they might choose to search their ‘half’ of the sky. Focusing on objects in the distance may help avoid empty field myopia. Operators should research the various scan techniques and train the ones most suited to their operation and environment.


Finally let’s look at a couple of characteristics of distant visual targets. Firstly, the diagram on the left demonstrates that geometrically an aircraft on a collision course will maintain the same position in the field of view as it gets closer. This means that there will be no angular movement of the target across the field of view and therefore our peripheral vision will be less likely to detect it until it is very close. The aircraft that is going to hit you may be the hardest to see.

On the right is a diagram that shows the visual arc described by an aircraft closing head on. This model is based on a closing speed of 600 knots but even if we halve that, it indicates that a target may only describe an arc of half a degree in our vision, when only 6 seconds from impact. It is still only 1 degree at 3 seconds, when the ‘avoid’ part is out of the question.

Monday, 23 September 2019

WHAT A GIRL (OR GUY) WANTS...

Looking at this representation of Maslow's hierarchy of human needs, would it be fair to say that most of us in the aviation industry (in the wealthy West at least) have taken care of the bottom 3 layers? We can probably expect to have food and shelter, a job with an income and some kind of family or community group to belong to.
If so, that means we are all principally motivated to a greater or lesser extent by a desire for RESPECT, RECOGNITION and STATUS. Why does that matter? Well it also means that those around us have similar motivations, and perhaps if we deliver them their needs they will probably deliver for us.

Worth a thought.

Tuesday, 2 July 2019

SPECIAL CONDITION FOR VTOL AIRCRAFT - EASA's EXPLANATION

Why a Special Condition?

EASA has reviewed more than 150 VTOL project configurations, at different stages of maturity, all aiming at addressing a potentially new market. The available data shows that there are a wide variety of configurations with limited common characteristics except for a VTOL capability and distributed propulsion. Despite having design characteristics of aeroplanes, rotorcraft or both, in most cases EASA was not able to classify these new vehicles as being either a conventional aeroplane or a rotorcraft as covered by the existing certification specifications.

Applying either the certification specifications for aeroplane or for rotorcraft, depending on whether they are rather an aeroplane or rather a rotorcraft, and only adding some modifications would not ensure equal treatment. These new types of vehicles are designed to address the same new market – even though not always the same segments. However CS-23 and CS-27 have significant differences, especially in terms of system Safety Objectives and Operational aspects. EASA opinion is that it would not be fair to treat applicants differently based on the regulatory starting point (CS-23 or CS-27) as it would probably favour some configurations, thus preventing potentially innovative concepts to compete on the market.

Instead, EASA favours to use objective based certification requirements, which provide the necessary flexibility to certify innovative state-of-the-art designs and technology, to establish a common set of conditions for the certification of these new concepts. Therefore EASA developed this VTOL Special Condition extensively based on CS-23 Amendment 5, which is also largely harmonised with the FAAs Part 23, integrating elements of CS-27 and new elements where deemed appropriate. Accepted Means of Compliance (AMC) will be developed and, when considered necessary, the most significant ones may be consulted publicly.

The establishment of a common set of conditions will enable a fair competition and clarity for future potential applicants. In addition, it will enable EASA to consider all vehicles with a Certification Basis based on the VTOL Special Condition as “Special Category” aircraft. This classification will provide greater flexibility in the Operational regulatory framework by enabling to tailor requirements to this type of aircraft rather than having to use aeroplane or helicopter regulations. 

Thursday, 20 June 2019

SAFETY PERFORMANCE INDICATORS... WHAT?

We have all learnt about safety management systems (SMS) and the 4 principal components - Safety Policy & Objectives, Safety Risk Management, Safety Assurance and Safety Promotion. Buried in Safety Assurance, within the sub-element Safety Performance Monitoring & Measurement are things called safety performance indicators or SPIs.

Most organisations have actually defined SPIs and slavishly track them at SAG and SRB meetings. But many don't really understand what SPIs are and what they should be doing for the business, so actually a lot of the effort is wasted on meaningless data.

Take a look at the diagram below - see how it shows SPIs as the very foundation of an integrated safety management plan:




Gates Aviation offers a one-day training course for aviation organisations, which clearly explains and demonstrates how to set useful and effective SPIs (and KPIs) that really answer the question:

"How good is our safety performance?"


Tuesday, 9 April 2019

PILOT TRAINING - ARE WE GETTING IT RIGHT?


The steering wheel of my old Reliant Scimitar motor car once came off in my hands while I was driving. That was certainly unexpected and the people who sold it to me would probably have said it couldn’t happen. But it did, and I had to figure out how to steer the vehicle while stopping in a safe (ish) place. I got lucky I suppose.



My thanks to Skybrary for https://bit.ly/2ImYXYY - a summary of the Preliminary Report on the investigation into the crash of B737 MAX 8 on 10 March 2019.

The way I read this summary (and I’m sure I’ll be corrected if I’m wrong), the aircraft was technically flyable, although not in a way the pilots had ever seen before and certainly not in a way they had trained for. In fact, they did manage to fly it for a while, overcoming the efforts of the automation to pitch the aircraft down into a suicidal dive, by nose-up elevator and electric stabiliser trim inputs. But eventually it won…

If we go back 10 years to AF447, the pilots were also presented with something they had never seen and had never trained for. The aircraft was technically flyable and operated to design but they couldn’t work out what was happening and correct it. The Air Asia A320 that crashed in 2014 was flyable, although the captain’s well-intentioned actions had caused the flight control systems to revert to ‘alternate law’. The pilots would have seen alternate law in the simulator but never with a sudden and unexpected onset.

I would be prepared to stake a substantial bet that each of these crews could have easily and competently managed an engine failure on the preceding take-off (and any other take-off). That’s what we have trained them for. But these other random, unexpected and potentially startling conditions are not trained and are therefore far more difficult to manage, just like my steering wheel incident.

So perhaps it is time be a bit more imaginative and a bit less optimistic when designing flight training profiles and show pilots some more extreme and unusual flight conditions.

Wednesday, 2 January 2019

WHY DO WE HAVE TO WAIT FOR A FATAL ACCIDENT?

The following bullet points are taken from the investigation report on a fatal turboprop accident in Nepal in 2017. The sad fact is that all of the listed operator deficiencies could easily have been identified and rectified in advance. No need for people to die and aircraft to be destroyed...

Think about getting a fresh and independent pair of eyes to review your operational safety performance.


My thanks to Skybrary for the text.