Air Safety – Flying an Ice Block

The task was quite simple. I had to take some computer tapes to Melbourne. My flight plan was equally non-inspiring; in fact it reminded me of a typical cross-country navex I used to endure whilst a flying instructor.

Although now working for a charter operator and usually flying twin-engined IFR aircraft, I had to admit that, in these circumstances, it didn’t seem I had made much progress in my aviation career. But it was all hours in the log and valuable experience.

I planned Sydney/Canberra/Corryong/Eildon Weir/Essendon at 8000ft. Sydney to Canberra passed uneventfully and being a well trained, although newly, instrument-rated lad I dutifully checked my weather for the next legs at Canberra. It looked really good – a nice steady tailwind would give me a ground speed of about 150 knots (freezing level 6-7,000ft). That would make up for the longevity of the C182. I had a twinge of conscience about cruising just above the 7800ft Lowest Safe Altitude, but it was only momentary as I would be in the clear all the way.

About thirty or so minutes out of Canberra, cruising A080, I just occasionally started brushing the cloud tops and decided it was time to make life easier and ask for a clearance to 10,000ft. Approaching my newly assigned level after a cruise climb, the tops were still growing. How about 11,000ft non-quadrantal?

I hadn’t made it anywhere near eleven before it was obvious that the weather was quite a bit different to what was on the forecast. No problems, that’s why one holds an instrument rating. In addition, it was a nice smooth day and I would be able to add some actual IFR to my growing log.

A greater Being than I must have been tuned in and decided to jolt me out of my complacency- all of a sudden I was flying this big ice block. Thick rime everywhere; windscreens, spats, liftstruts, wings and aerials and getting thicker all the time. It formed quicker than you could say longitudinal dihedral. Anybody with even a rudimentary knowledge of aircraft knows that an ice block has the aerodynamic characteristics of, well what else, an ice block and I didn’t like the flavour. The airspeed was bleeding off quickly and my elderly charge started to descend. By the time I had increased power to climb power, the best I could achieve was 85 knots indicated and a steady 250ft per minute down.

To say that I had my heart in my mouth would be an understatement. I called Flight Service and told them that due to severe airframe icing, I required a lower level- no problem. FS are so helpful with such requests.

At this stage I was suffering from a terminal case of sweaty palms.

The old bird was fitted with one of those slipstream-operated anti-bug devices on the pilot-head and, of course, this friendly, if agricultural device had no anti-ice heating. I must admit with some hindsight that I couldn’t imagine what any normal self-respecting bug would be doing up there with me in those conditions anyway.

It just seemed like the final straw on the Superior Being’s part that he proceeded to demonstrate how much trouble I was in by cultivating this 15-centimetre stalagmite (or was it a tite?) from the fly-trap mechanism up past the front of the pilot intake like a sort of gnarled witch’s finger; like the one that gave you the shivers when you were dragged along to see Snow White.

Unconsciously, I started to edge to the west of track away from the high ground but Melbourne Control bobbed up and verbally chastised me for drifting off track. Could you believe it, I muttered an apology and re-intercepted my planned heading.

The 250ft per minute in the direction of down was steadily eroding the altitude and I wished I was back in my old job in the grocery shop eating chocolate biscuits and smiling at little old ladies.

I had been dutifully obtaining clearances as we sank through successive levels. However, I gained some sort of perverse enjoyment out of informing the controller, who told me that clearance at a lower level was unavailable because I would be outside controlled airspace, that I had little to do with where the ‘bloody thing’ was going and they had better tell the aeroplane.

Somewhere between seven and six thousand the ice started to melt off and the stall warning started crying like a baby (it had obviously been iced over previously). I managed to maintain altitude arid my composure for a while. Then I knew I must have done something to offend the Great Architect of Nature, the aircraft packed on another lot of ice – some sense of humour. The stall warning was screaming continuously to keep me company. Lowest Safe Altitude had long since gone and I knew I was going to die.

I fought the aircraft down from about 6,500-6,000ft to between 4,500-4,000ft and figured that I would probably come into contact with terra firma at any minute when the ice started to melt. It came off the prop and slabs of it started sliding over the windscreen and, more importantly, the vertical speed indicator was reading zero.

Almost at the same time, we broke out of the cloud into the clear. I was able to identify my position, with some assistance from Melbourne, as being in the vicinity of Taggerty about 8nm south west of Eildon. In the sixteen years since this incident occurred, I have often mused over how lucky I was to survive and have reflected on how I could have improved my chances. I have also wondered how close I came to ending the flight as a Bureau of Air Safety Investigation accident statistic.

There is not word of exaggeration in the above story except I probably haven’t been able to convey the terror.

Since it happened, I have looked at maps of the terrain and wondered. The stress of the situation compressed time and it seemed that everything happened at once.

Having to confront the task of preparing this story has reawakened the memory and I have endeavoured to retrace my descent profile to answer the questions mentioned above.

I have calculated that I picked up the first batch of ice just south west of the Corryong aid. At a reduced ground speed of about 125-130 knots and a rate of descent of 250ft per minute I figure my descent was temporarily arrested by the loss of the first batch of ice at about 6,500ft only 10 miles short of The Hump (5,653ft)­ Mt. McLeod (5,050ft) high ground.

The second batch of ice must have been picked up about 15 minutes later at 6,000ft in the vicinity of Mt. View. Looking at my track from here to Taggerty, I descended to 4,000ft passing country which goes up to 4,9OOft!

If I had not lost most of the first batch of ice when I did, my crash site would have been located on the eastern side of Anderson Peak.

The Lessons

What did I learn from this experience? Firstly, it taught me that there are certain things you don’t do in a single engine, fixed gear aeroplane, particularly in winter, like flying over the highest country in Australia enmeshed in cloud. IFR in single engine aeroplanes of the type specified runs a close second.

Third, as soon as the problem occurred I should have referred to a WAC and headed West young man. In fact, my colleagues have asked whether I had a WAC at hand. I certainly had one in the aircraft, but under the pressure of the situation, I must admit it didn’t enter my head to seek it out. In any case, irrespective of the fact that the flight was IFR, I was well aware that the country was a good deal flatter and lower to the west of track, so why didn’t I declare an emergency and dial up an aid such as Albury?

Looking back now with the benefit of hindsight, broader experience and greater knowledge, it is hard to believe anybody could be so dumb and still remember to breathe. Why did I stick to that track when with the height in hand and good radio communications, a diversion to the flat country could have been accomplished with very little drama at all?

I hadn’t heard of ‘human factors’ in those days or of the channelling of attention under stress. The only thing I did right was to keep flying the aeroplane.

Sequel

Returning to Sydney that night a very chastened and much wiser pilot I flight planned way out around the flat country below the 0° level. Was Huey pleased with me?

Well maybe, but he certainly wasn’t finished with me because for two hours he turned on torrential rain and the worst carburettor icing I have ever encountered in my twenty-three years of flying. But that’s another story.

In flying particularly, complacency breeds contempt and contempt for the equipment and the environment often kills. We should all review our attitude to our flying and avoid placing ourselves in situations where we have to learn ‘on the job’.