Who is the pilot in command? A faulty assumption leads to an accident
Maralinga is a 3,000 sq km section of desert in South Australia. The British Government tested atomic weapons there in the 1950s. In the 1990s, the Australian government completed a successful decontamination of the site. Though my main work was based in Canberra, I needed to visit the Maralinga site about four times a year. I was an owner of a Cessna 172 and I used it to travel to and from the job. Canberra to Maralinga is approximately 2,000 km and I would always go via a different route and enjoy different scenery. Sometimes I would take my two young boys. We enjoyed my flights to Maralinga.
Over the years, I began to tire of CASA inventing mandatory ways for me to spend my money, such as:
Unnecessary maintenance directives,
Insisting I pay for security passes when I already had higher level passes for my work,
Escalating tower charges, etc.
At an air show at Narromine I met a friend who had recently built a Savannah aircraft. It’s a two-seat, short field performer, could land in a farmer’s paddock or on clay pans in the desert. I flew back to Tumut with him and I liked the Savannah. I agonised for a week and then I ordered a kit for $60,000. There would be a three month wait.
About then I had a month of work at Maralinga. I flew there in the 172. By then the main work had finished and the site was mostly in mothballs. I was the only person on site.
Maralinga is now deserted, but once hosted bombers.
I heard there were two Western Australian men then at the Brisbane Savannah agent’s hangar finishing off a new Savannah. They would soon be flying it home to Perth. I contacted them and invited them to overnight at Maralinga and they accepted and arrived a few days later.
When I meet new people there is a silent computer in the back of my head that assesses them. Are they talking sense, is their story credible? We all do that, though some may not admit to it. Mick and Jim were about my age, they were jovial, their speech was a bit rough, but they had a lifetime of experiences. They quickly fixed a generator that had been giving me trouble. I was very impressed by their knowledge and skills. I quickly dismissed my reservations and developed a confidence in their judgement.
We agreed we would fly a few circuits in the Savannah after lunch.
They were good company and we got on well—maybe too well. When we went to the airfield to fly the circuits, there was much joking and laughing about operating the Savannah, a small aircraft, from an 8,000-ft runway that had been built for nuclear bombers. The weather was perfect, we were in high spirits, but there was no discussion about our respective licences and experience or check procedures. We were just a couple of pilot mates going for a fly—what could go wrong? With hindsight, there was a lot that could go wrong.
As we arrived at the plane Mick said, “Dave you take the left seat.” I remember thinking that he wouldn’t have offered me the left seat unless he knew what he was doing, because flying from the right requires reversing your hand reactions and although not hard, it does require practice.
As we taxied out, Mick gestured to me to also have my hands on the controls and to make some of the control inputs, which I did. We taxied to the end of the runway, checked the oil temp, and commenced our takeoff roll. At about 200 ft, Mick took his hands off the controls and gestured to me that it was all mine. On reflection, there had been no discussion about lift-off speed or rate of climb or anything like that. Our start-up and takeoff had been more like a committee environment, with both of us making control inputs at our own discretion.
In comparison to my Cessna, I found the Savannah to be very light and to fly like a feather. Small changes in the controls caused significant changes in the flight and I had difficulty holding a steady height. Being unused to the centre stick, my movements were a bit jerky. I purposely did a very long downwind to allow a long final and I overran my turn out of base. I was feeling very uncomfortable and as soon as I had it roughly aligned on the runway, I decided that the safe thing to do was to hand control to an experienced Savannah pilot. So I said, “You take it, Mick. You have control.” To avoid any misunderstanding I placed my hands in my lap.
Mick looked very surprised. He had assumed I would fly the whole circuit, but he took control. My best estimate is that we were at about 300 ft above the ground when I passed control to Mick.
I was relieved that the plane was then under the control of a pilot with Savannah experience, but I soon realised that Mick was having his own troubles as he pulled off too much throttle and then over-corrected and we climbed momentarily before he pulled off too much throttle again. He was clearly getting flustered and making mistakes and he started swearing and shouting about the jumpy throttle. I did not know whether he was shouting at himself or whether he wanted me to make throttle inputs, but I considered that the last thing we needed was two pilots making inputs so I purposely left my hands on my lap and kept quiet as we continued a crazy up and down descent.
Then in response to one of his shouts and his hand gesturing for me to rotate the left side throttle friction nut, I completely loosened the left side friction nut. Out of all that chaos and a few more over-corrections by Mick, he managed to make a smooth touchdown and I was very relieved as we ran along the runway for a few metres.
Then suddenly the engine was at full power and the plane was climbing steeply. At about 40 ft, the engine suddenly went to idle revs and we nosed over and dived towards the runway at about 45 degrees. It all happened so very quickly. The nose wheel came up through the cabin floor and we skidded along the runway on the bottom of the fuselage with a collapsed left wing and the propeller making a sickening noise as it smashed itself to pieces on the runway.
Small, slow airplanes are still plenty fast enough to be dangerous.
The Savannah was badly damaged but not a write-off. Like most small planes, it was uninsured. After some discussion we decided I would fly Mick to Kalgoorlie in my 172 (about 1000 km west of Maralinga) and Dick would catch the train to Perth and bring back his truck to take the damaged Savannah home to Perth. As we flew to Kalgoorlie, Mick did not seem to want to talk about the accident but I was able to learn later from Jim that although Mick was licensed and had flown the Savannah from Brisbane, he did not have much flying experience prior to that.
Three days later Mick arrived back with his truck and we loaded the plane. We agreed that I would contribute to the repair costs and they departed.
It was not until about a year later, when I was assembling the throttle controls on my Savannah, that I realised what was a major factor in the accident. The Savannah has two push rod throttles, one on each side of the instrument panel but linked together forward of the panel. Each throttle has a hand operated friction nut and the flying pilot has his friction nut set at firm and the other side friction nut set at loose. If the friction nuts are set in reverse, it causes the throttle to operate in jumpy increments.
The Savannah has a Rotax engine with a safety spring on the carburetor so that if the throttle linkage breaks, the carburetor goes to full open throttle. This enables the pilot to fly on to an airfield and then turn off the fuel or the ignition and glide down and do a safe landing.
When Mick and I entered the Savannah, there would have been normal firm friction on the left throttle nut and nil friction on the right throttle nut. When Mick took control, he was operating the right throttle and it responded in jumpy increments, causing him to continually overcorrect the throttle. After he had me loosen the left friction nut, his control improved and out of all that chaos he managed a good smooth touchdown.
It is easy to now identify the many mistakes that we all made:
- When Mick said, “Dave, you take the left seat,” I wrongly assumed that Mick would not have said that unless he had significant right seat control experience. I should have questioned that. I now think he had so little general flying experience that he did not appreciate that flying the Savannah from the right side would be different.
- Because Mick knew that I had ordered a Savannah kit, he wrongly assumed I had significant Savannah flight experience and would fly all of the circuit. I only had two hours as a Savannah passenger.
- Mick was surprised and unprepared when I passed control back to him. He found himself, at short notice, having to use his left hand on the control stick and his right hand on a jumpy throttle. This was something he was not ready for and it flustered him.
- When Mick eventually achieved a smooth touchdown, he felt so relieved that he let go of all of the controls. That is poor technique; a pilot should always maintain control, in the air and on the ground.
- Neither Mick nor I were aware that if both of the throttle friction nuts are loose and the throttle is released, the carburetor immediately goes to full power, which it did.
- The Savannah has a high lift wing and as soon as the engine went to full revs, the Savannah leapt into the air and began an uncontrolled steep climb. At that stage Mick or I could have pushed the stick forward and initiated a go around and sorted things out. Neither of us had the presence of mind to do that. Mick reacted by pulling off the throttle and we plummeted to the ground.
The way I see it there were two main factors in this accident.
- Every pilot, from their first lesson onwards, gets it drummed into their heads that they must do their daily checks. This included, among other things, knowing how the controls work and the ability and experience of your fellow pilot. We failed badly on that fundamental check.
- There was also a human factor. I had not seen another person for over a week, so I was looking forward to their visit. When we all got on so well, it induced an almost festive feeling in the air, like being on holiday. I do not offer it as an excuse. But that good feeling in the air partly explains how a normally boring, cautious pilot like myself dropped my caution. I neglected the fundamental checks. It may explain it—but nothing excuses—the negligence of the mistakes that we made that day.
Also of interest: Remote Flying in Australia – a Pilot’s Perspective
‘Who is the Pilot in Command’ is from Air Facts Journal
