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Dropping an Otter

Dropping an Otter 12 October 1984

1984 was a good year for me to drop things. I told you about killing Bond in January of that year, but it was in October that a more disastrous fall is recorded in my log book.

A pilot in the mountain kingdom of Lesotho took off from an airfield at an altitude of about 10,000 ft above sea level. He was flying a Twin Otter, which is a very reliable and iconic workhorse of an aeroplane with two engines and a seat capacity of twenty. Shortly after take off, the aircraft suffered an engine failure. The pilot should have been able to fly away from that situation on the remaining engine, but he made the mistake of turning back too sharply and too soon to land on the runway he had just left and could not maintain altitude in the turn. The result was the aircraft crashed.

Insurance assessors sent to examine the wreck determined that if the Otter could be recovered without further damage, it was financially worth it. The margins were tight, however. An expert team, contracted by the insurers, was sent from Canada to carry out the aircraft’s recovery to a place where it could be repaired. To truck the machine out by road and take it to the capital, Maseru, was out of the question. The single track, rock strewn mountain road would probably have inflicted even more damage on the wreck. The only other way to move the machine to Maseru was to lift it out by helicopter, and the only helicopter powerful enough to do it at that altitude was a Bell 412. I wanted to use ours, which was better equipped, but the Lesotho authorities insisted on using a government machine. As the Lesotho pilots had no experience in cargo slinging, I was asked to do the job using their machine, registration number LPF-24, (Lesotho Police Force).

The team of Canadian riggers, our engineer, Mo, and myself got together in Johannesburg before going to Lesotho. We had a disagreement over the steel cable they’d made. This sling would link the Otter to the cargo hook under the helicopter’s belly. I said it was too short and the looped end should have a metal eye inserted to prevent it from fraying. The rigger scoffed at the idea and claimed they had done plenty of helicopter lifts, and their slings without eyes had always worked.

I had the impression he had consented to a change of sling, but when we got to the mountain airstrip, miles from anywhere, with all the money having been spent so far on this recovery, I found they had not altered the strop at all. To go back to Johannesburg and construct another sling would be a major hold up and would stretch the insurance company’s patience – after all they were paying for all this.

Like a fool, I gave in and accepted that we were forced to use his sling, short and without the eye I’d requested.

Another problem was the police helicopter I was to fly. It had a cargo hook, but it was not equipped with a mirror which allows the pilot to watch the load beneath him. As some loads behave in hazardous ways when subjected to airflow, a mirror is an essential piece of safety equipment – the pilot might have to jettison the load if it becomes dangerous in flight in order to save the helicopter.

Again, the pressures of the situation: the remoteness, time was short, the expense, they all mounted to push me into accepting the situation.

To prepare the Otter, the Canadians had removed the wings with the engines and the heavy nose landing gear. So what was left was an empty fuselage including the tail fin.

After a trial lift which showed the fuselage was hanging tail low, they adjusted the rigging and we tried again. Remember, I couldn’t see the load without a mirror.

I had no idea what speed I would be able to make on the trip back to Maseru, but guessed I could do 80 knots. The fuel required for this speed meant there wasn’t much time to play with, and more fuel would make me too heavy.

Mo, the engineer, was to follow me in a light aircraft and tell me how the Otter was behaving, at least in the early stages of the flight. I lifted the fuselage, it was hanging well and so I took off. I could feel the drag of the load as I accelerated. We reached 60 knots and then Mo warned me that the tail fin of the fuselage was rising and getting close to my tail rotor (a longer sling would have obviated that). If 60 was the maximum, then was there enough fuel for the extended time it would take?

The weather was good, with a layer of broken cloud at 11,000 feet. I flew above this to avoid having to dodge mountain peaks en route. The shadow of the helicopter and the load beneath with a halo of a rainbow around it was visible on the top of the cloud. Since all was now stable, Mo in his much faster little aeroplane went ahead to Maseru to receive me.

Intending to descend through one of the many holes in the cloud layer, I reduced power. Instantly, the load swung. Reducing the rate of descent made no difference. The slightest downward movement caused the fuselage to oscillate and the helicopter rocked gently from side to side. It wasn’t uncomfortable and I had to get down, so I accepted it. Pilots are very reluctant to jettison loads unless it’s really necessary – it’s a pride thing, I suppose. However, when I saw the load out to my right and almost level with me, it gave me a fright. Then it was out to the left and I thought seriously about jettisoning the thing. If it wasn’t allowing me to descend without that extreme swing I wasn’t sure I could make Maseru before my fuel ran out.

Safety of the aircraft is paramount. I was fully within my rights to jettison the load, but I didn’t, I hung on, descending ever so slowly and hoping to get down without disastrous consequences.

Then the swing stopped. I looked out at the shadow and saw the load was no longer there. It had gone. I’d lost it, but I was alive and could easily make Maseru. I knew what had happened, of course. The swinging had caused the loop in the cable, which had no protective eye, to fray and break.

From another military helicopter we found the wreck not far from a village. It was finished, its back was broken and from being a borderline financial prospect, it was now a total loss (the cost of a used Twin Otter today is upwards of $3 million).

Worse, from my perspective, was that although the cable was frayed and would have failed eventually, it hadn’t, and so the suspicion that I had released the load mounted and I was worse than the worst in the eyes of the insurers and the Canadians.

The insurers wanted to sue for their loss, but back in the hangar in Johannesburg we took the cargo hook from our own Bell 412 and linked it to a similar cable to the one that had held the Otter. We proved that at least 4 times out of 5, that such a thin cable without an eye and under conditions of no load can detach itself from the helicopter’s hook. To explain: when the load was vertical its full weight was on the hook. When at the top of its swing out to the side of the helicopter there was no load on the cable, the loop would open and it would unlatch the hook’s gate. I don’t want to get too technical here, so please accept the explanation. Mo will bear me out, won’t you?

The lesson I learned from this was never to succumb to pressure to do things the easy way when you know you’re right. And I would never fly another load without a mirror.

Publishing news is that I’ve been plotting the sequel to Thirty-Four and have at last begun to write it. Months of work ahead on that one. I’ll keep you posted.

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