Air Safety-Two Kinds of Pilots

Anyhow, back to the point of my own story. At the time it happened I was flying for a small charter outfit based at Adelaide’s Parafield Airport, where I’d accumulated something over 1,000 hours on their well maintained Twin Comanche. At this stage my total time was more than 3,000 hours, so I wasn’t exactly a new chum.

The aircraft had been chartered by the Government Department then responsible for Aboriginal welfare to take a couple of minor Departmental pooh-bahs on a round of visits to several isolated Aboriginal community centres. The planned three day trip promised to be interesting, well off the usual beaten tracks, and I was looking forward to it.

On the appointed morning, my two passengers turned up with their luggage as planned, and we were airborne, on track for Ceduna, a few minutes after 0900 hours local time. The weather was fine and quite mild, despite the moderate nor-westerly airstream ahead of an approaching weak front, and as usual when a high lies over South Australia, the air was crystal clear – the sort of day when you feel you could almost reach out and touch the peaks on the horizon.

The wind was right on the nose for our first leg, but we still made good a ground speed of 140 knots, and by 1000 hours we had crossed both gulfs and were looking down on the little town of Cleve. Forty five minutes later, the blue water of Streaky Bay lay ahead and a little to port, contrasting welcomingly with the grey brown Eyre Peninsula landscape, with the capes and islands of the far west coast visible in the distance beyond. At 1115 hours we touched down on Ceduna’s Runway 29 and taxied in to where the local Air BP agent was waiting to refuel us.

Awelcome “cuppa” with the Flight Service staff of happy memory and we were on our way again, climbing out over the cobalt waters of Murat Bay, on track this time for Yalata Mission, another 100 nautical miles to the north west.

Any useful radio aids were now behind us, but visual navigation, at least on this leg, posed no problem, – it was hardly more than a matter of keeping the Eyre Highway and the Bight on our left. The Yalata strip, set in dense scrub close to the eastern extremity of the Nullabor Plain and only 30 miles short of the Head of the Bight, held no terrors, and a few minutes after landing we were sitting down to vast helpings of roast mutton and baked potatoes (no vegetables) in the mission house kitchen, presided over by an able middle aged Aboriginal woman.

The meal over, I was left to my own devices for a couple of hours while my pooh-bahs attended to affairs with local community leaders. Joined then by a third passenger, it was back to the airstrip in a dusty, battered Toyota Land cruiser for our late afternoon flight north to Coober Pedy for refuelling again, then on to the Aboriginal community at Indulkana near the Northern Territory border. Here we were to drop our third passenger before returning south as far as Marla Bore for our first overnight stop.

This time, on a north easterly heading into the very centre of “remote area” South Australia, with only a transistorised NBD at our first destination and few en route landmarks, I really had to navigate – what the Americans like to call “pilotage”. With the WAC chart on my knee I kept check of our progress continuously, so that at any point I could say, “we are there”.

Shortly after half way, the Wilkinson Lakes lay abeam in the distance to port, confirming we were at least close to track, and a little later the unmistakable twin lakes formation of Phillipson and Wirrida was showing on the horizon ahead. And lo and behold – there was the ADF needle unambiguously pointing the way to the ancient, erosion worn hills of Coober Pedy!

My passengers were met, after we’d overflown the settlement and landed, by an official of some sort who turned up in a mud encrusted Land Rover, and they talked business while I attended to the refuelling with the local agent.

On the flight north I’d noticed a few patches of large cu developing into what looked like cu-nimbs out to the west, presaging the arrival of the expected weak front, but they seemed fairly scattered and I did not expect the change to bring any significant weather. But now as I checked the fuel tank drains, I noticed the sky to the north east had become quite dark

After we had taken off, it was plain to see that the weather all around us was deteriorating – there were now large patches of cloud to the north and north west as well, from which rain was falling.

Neither Indulkana nor Marla Bore boasted NDBs, but this was of little consequence on the leg we were now flying – both were signposted by the very visible “iron compass” – the standard gauge railway running north from Tarcoola to Alice Springs! With so much thunderstorm activity in the making, the ADF would probably have been confused anyway.

For a time, flying at 2,500 feet, we were able to avoid the worst of the weather by weaving between some of the now angry looking patches of cloud and rain, encountering occasional pockets of sharp turbulence as we did so. The changein flying conditions had not escaped my passengers, their set expressions now reflecting their inner feelings. Soon after passing abeam Mt Willoughby homestead, about 80nm north of Coober Pedy, we flew directly into continuous heavy rain. With forward visibility dramatically reduced, I was thankful for the presence of the railway line, just visible out of the corner ofmy eye offthe port wing, leading us in a geometrically straight line towards our northwestern destinations.

The relatively new settlement of Marla B<lre hove into sight through the rain and as we passed over, I saw that patches of its graded gravel airstrip had become miniature lakes – we wouldn’t be landing there for the night, that was for sure!

As we pressed on towards Indulkana, the rain abated temporarily and dimly, only a few miles to port at about our own altitude, I made out the unmistakable blue black, cigar shaped clouds of a vicious line squall. It was high time to give it away!

Swinging the aircraft around on to a sou-easterly heading, I turned to my passengers, offering them the choice ofgoing back to Coober Pedy or diverting to Oodnadatta. They opted for the latter – though not included in their itinerary for this trip, a call on the community there would still be useful.

I Oodnadatta,just over 100nm to the east, and in only a few minutes we flew out of the pre-frontal weather into clear, late afternoon sunlight. Ahead ofus in the distance, beyond the weathered remnants of what millions of years ago was a great tableland, stretched the north and south branches of Neales Creek, their broad dry courses clearly etched across the red landscape by the trees : flourishing in the creek beds. On the far horizon, the convergence of the two branches pointed to the position of Oodnadatta.

Half an hour later, I at last picked out the tiny collection of buildings set on the eastern edge of the Neales,their presence fantastically shrunk to ant like proportions by the majestic scale of the outback vista. We descended, joined the circuit, and landed smoothly into the light nor-easterly on Runway 04 – clearly no harbinger of the approaching front had yet penetrated as far as Oodnadatta.

A visiting Departmental radio technician drove us across the mile of parched gibber plain that separates the aerodrome from the pioneer settlement, dropping us at the Transcontinental Hotel, a rambling bungalow of a building distinguished only by the sign on its iron roof.

We were out of luck A survey party hadjust “come in from outback” that afternoon, the jovial overweight publican told us, and all his accommodation was taken. But he’d be glad to give us a meal about 6. 30pm.

Have you an air safety story to tell? Particularly one with a lesson that might save other pilots from making a similar error of judgement? If you have, write to Macarthur Job, cl- Australian Aviation, PO Box 3105, Weston Creek, ACT 2611. Contributors to this series are assured their anonymity will be fully respected!

We fell back on the local Aboriginal community “hostel” a few doors down the line of ramshackle buildings facing the township’s wide unpaved main street. A former railway ganger’s house, it had been transferred to the Department responsible for Aboriginal welfare after the old narrow gauge line to Alice Springs had been abandoned. The “hostel” had no staff and was merely a place where visitors could cook, eatand sleep. It was going to be a rough night -there were old mattresses to lay on the floor, but no blankets or bed linen. The one consolation was that the weather was mild. Didthis have any bearing on what was to happen late the following day?I’m sure it didn’t help.

After we had eaten at the Transcontinental – a hearty meal of steak, served with chips and salad vegetables, unimproved by their long haul from Adelaide – we were visited at the hostel by local Aboriginal community leaders for a couple of hours, then it was finally time to turn in.

Somehow, despite the basic amenities and the hardy species of mosquitos they breed at Oodnadatta, I managed some sleep. Somewhere around midnight, the front we had fled from in the late afternoon caught up with us and rain drummed on the iron roof for the rest of the night. It was still raining lightly when we awoke in the morning, but by the time we were trekking through the mud to the Transcontinental for our breakfast, the sun had broken through.

The publican greeted us with more news we could do without. “You can take yer time gents – drome’s closed ‘cos of the rain,” he told us as we took our places in the little dining room. And it wasn’t only the aerodrome that was affected – the main roads out of Oodnadatta to the south and west were impassable and likely to remain so for the next couple of days at least.

More to kill time than anything else, I wandered down the “street” after breakfast to where the southern outskirts of the settlement border the eastern boundary of the aerodrome. The red mud clung to my shoes in layers more than an inch thick and I marveiled at how quickly this remote inland could become a vast quagmire. But the old established runways looked all right. In fact I was surprised that they were affected by the rain at all – their appearance gave the impression they’d been sealed in the distant (wartime?) past. Fervently I prayed the sun would dry things out quickly; there was a charter flight to Tasmania awaiting me when I got back to Parafield and I certainly didn’t fancy another night in the doubtful comforts allotted to us.

A mid morning telephone call to the aerodrome groundsman confirmed that nothing had changed. Neither was his tone encouraging of any compromise for the sake of our departure later in the day. I decided it was useless to argue on the telephone; better to go out to the aircraft late in the day, packed and ready to leave, and see what personal pleas could achieve.

My passengers had things they could do with the local community, but for me the day passed slowly. After taking in the few sights the historic settlement had to offer, I took tea with the AIM nurses at the little hospital founded by Flynn of the Inland, then sat down in the Transcontinental to revise our flight plan.

The passenger from Yalata had decided that, as I couldn’t get him to Indulkana, he’d get me to drop him at Coober Pedy on our way south again; he was confident he’d get a ride back to Indulkana from there the next day. After that we’d continue back to Ceduna as planned for our final overnight before returning to Parafield. The changed circumstances meant that, even at best, we’d be in the dark from Coober Pedy to Ceduna, but that was of no consequence in the fully IFR Twin Comanche.

Finally it was time to try for our departure. At 1630 hours we got a lift back to the aerodrome in the AIM hospital Land Rover and I loaded our gear and preflighted the aeroplane. By this time it was becoming overcast again and the groundsman grumbled that the runways were still too soft. But he agreed to take his yellow Departmental five tonner out on to the movement areas to have a look

It wasn’t the wisest decision. Driving up Runway 04 about 200 metres east of the intersection with 13, the heavy vehicle’s wheels broke through the surface crust and it became bogged. He strolled back, muttering “What didI tell you” as he passed us on his way to the equipment shed.

I said nothing. Instead I walked out via the taxiway to the nearby threshold of Runway 13 and along the runway itself. The eastern side seemed quite firm – certainly firm enough for our aircraft.

I reported back to the groundsman, tactfully pointing out that our Twin Comanche was a lot lighter than his truck! When he demurred, I looked him in the eye and he countered by saying he would call Alice Springs for instructions. This he did from the old Flight Service office, the OIC at Alice Springs pointing outit was a matter for the pilot, but commenting that the weather wasn’t too good.

I took the microphone and said: “Read me the forecast. ” He did and it didn’t seem too bad if we left at once. Although the wind behind the front was generally light, low cloud was expected to roll in and to complicate matters the Coober Pedy NDB was temporarily out. But if we could beat it into Coober Pedy before dark we should be right. If we didn’t – well we could always divert to Leigh Creek. I read out my flight plan for Coober Pedy and Ceduna, and he accepted it without further ado.

Hurrying back to the aircraft, I hustled the passengers aboard, started the engines, and tax to the threshold of Runway 13, hoping against hope that the surface crust would hold. I ran up the engines into the wind on the runway itself to avoid unnecessary manoeuvring then, holding the control wheel back to take the weight off the nose leg, I opened the throttles gently, alert for any sign of bogging.

The ground was obviously heavy and we gathered speed slowly at first. With the control wheel still well back, I gently lifted the machine off as soon as it would fly, holding itjust above the ground as we accelerated – this was one time when takeoff safety speed had to be compromised. But all was well, the undercarriage came up as we crossed the upwind fence, and we were on our way.

Already the cloud base was closing in and we flew to Coober Pedy visually at 500 feet, my passengers remarking at the lunar like landscape speeding close beneath us. Where the Oodnadatta-Coober Pedy road crosses Arkaringa Creek, 40nm south west, we spotted a laden semi trailer bogged up to the axles in mud. We could do no more than waggle our wings in salute as we flashed past.

Touching down at Goober Pedy just as the last rays of the sun were shafting through a break in the cloud to the west,we dropped our passenger, and took off again immediately. As the aircraft settled into the climb in the gathering dusk, I heaved a sigh of relief – all should be plain sailing from here on, I thought.

How w rong I was! About 20 minutes later, now cruising at 6,000 feet in near darkness above cloud with the anti collision, navigation and instruments lights on, the generator warning lamp for the port engine suddenly illuminated. For a moment I thought about returning to Goober Pedy, but with the NDB there not operational, I decided firmly against it. The ammeter did not appear to be indicating any discharge and I felt the best thing to do was to continue to Ceduna as planned.

A little later however, I was alarmed to notice that the generator warning light for the starboard had also come on, though only faintly. As a precaution, I turned off all the aircraft’s electrics with the exception of the VHF COMM and the instrument lights. Again I could do without the ADF, at least at this stage of the flight. Better conditions were forecast for the coast and I should be able to pick up Ceduna’s rotating light without difficulty.

This proved to be so about an hour later, and I turned on the nav lights again, let down into the circuit for a landing on Ceduna’s illuminated Runway 11 and, as usual on the downwind leg, selected the undercarriage down. As I did so, the instrument and nav lights suddenly went out and I found myself flying in almost pitch darkness with only the two generator warning lamps glowing at me.

There was no sign that the undercarriage had extended – apart from no visual indications, there had been no characteristic “thump” – so I recycled the selector. Again there was no result, except that the lights came on momentarily each time the selector passed through the neutral position.

Instructions for Emergency Extension of Landing Gear

1. Reduce power airspeed – not to exceed 100mph.

2. Place landing gear selector switch in centre “off” position.

3. Disenga§e motor – raise motor release arm and push forward through full travel.

4. Remove gear extension handle from stowage. If left socket is not in clear position, place handle in right socket. Engage slot and twist clockwise to lock handle. Extend handle and rotate forward until left socket is in clear position. Remove handle and place in left socket. Lock and extend handle. Rotate handle forward fu//travel to extend landing gear. Green light on panel indicates landing gear down and locked.

Note:

Reducing power and rocking gear extension handle will aid in manually extending the landing gear. Do not retract with handle in socket Do not re-engage motor in flight

Realising there was insufficient power left in the battery to lower the undercarriage, and that what was left was being drained even from the lights each time I attempted to energise the undercarriage motor, I calledFlight Service and told them I would have to lower the wheels manually. In preparation for doing so, I climbed back to 2,000 feet and positioned the aircraft to the north of the field where I was clear of the circuit area but could see the town and aerodrome lights. While I was still communicating with Flight Service, their signal faded and I found I was talking to myself.

As the instrument lighting was still holding, I turned on the cabin lighting to see what I was doing, but as a precaution I also took out the aircraft’s handed it to the front seat passenger.

Removing the undercarriage electric motor access panel from the cabin floor between the two front seats, I studied the directions placarded on its underside. They read:

Attempting to follow the steps one by one, I located the motor release arm, raised it and pushed it forward until I felt firm resistance – a position not much beyond the vertical. Then I unclipped the emergency extension handle and locked it into the right hand socket of the undercarriage retraction torque tube. Having done this, I eased the power back on both engines and gradually reduced our airspeed. Finally, when I had the aircraft trimmed to fly level at 90 knots, I pushed forward on the handle as instructed. It refused to budge!

Unlocking the handle again, I fitted it into the left hand torque tube socket and tried again, but still it refused to move, even when I pushed hard with both hands.

By this time it seemed to me that the cabin lighting was becoming dimmer. Not wanting to lose the instrument lighting on top of our other troubles, I promptly switched off the navigation and cabin lights again and had the front seat passenger turn on the torch and hold it for me while I went through the placarded instructions again, checking that I had followed each correctly. I pushed hard on the motor release arm again and it seemed to be as far forward as it would go; I tried again with the handle in each ofthe torque tube sockets, but nothing would give. I just couldn’t see what I was doing wrong!

All this time of course, I was still trying to fly the aeroplane as well, but we were all over the sky. At one stage I looked up from what I was doing to see we were in a 45 degree bank and the airspeed was settling back towards 70 knots – a decidedly unhealthy situation in aTwin Comanche! Finally I saw it was no good. Mindful of the Lockheed Tristar that flew into the ground in Florida at night simply because the flight crew were all preoccupied with investigating why the green nose leg light had not come on when the undercarriage was lowered, I decided I had no alternative but to land wheels up.

After packing things away, informing my passengers what we were about to do, and instructing them to tighten their seat belts, I turned on the navigation lights once again and did a low run over the apron in front of the Flight Service building to alert them. Then, with my heart beating noticeably faster than usual, I positioned the aircraft on a wide base leg and made a long shallow flapless approach.

The touchdown itself was surprisingly smooth and we slid to a stop on the lucerne covered runway after only about 150 metres. Only the propellers were damaged. After all the tension and anxiety, it was almost an anti climax.

* * *

When the air safety people and one of our company engineers arrived from Adelaide the next day, they found that the voltage regulators for both engines had coincidently developed quite separate faults. The aircraft’s battery had progressively discharged as a result,so that by the time we arrived over Ceduna, there was insufficient power left to energise the undercarriage motor. The problem With the emergency undercarriage extension system proved to be nothing more than an excessively stiff motor release arm which had prevented me moving itforward to the fully disengaged position. In flight in the dark, while trying to control the aircraft at the same time, I had moved the motor release arm forward only to the point where excessive force became necessary to push it further. Although I thought this was the fully forward position, it had still not disconnected the undercarriage mechanism and so I was unable to move the emergency extension handle.

On the ground in the calm light of day, we found that, despite the stiffness of the motor release arm, it was possible, even if only by pushing very hard, to force it through to its full travel where it disengaged the motor.

All this of course is a case of being wise after the event. But why, it might be asked, was a commercial pilot with a 1,000 hours on a particular aircraft type not thoroughly conversant with the operation of its emergency undercarriage extension system?

The answer, dear reader, is the idiosyncrasy of the Twin Comanche’s undercarriage system. On most aircraft types, the emergency undercarriage extension system is demonstrated and practised during endorsement training. On the Twin Comanche this is simply not possible- once lowered using the emergency system, the undercarriage cannot be retracted again in the air. Instead the aeroplane has to be landed, jacked up in the hangar, and the mechanism reset by a LAME, a task involving expensive workshop time. One’s familiarisation with the system is thus limited to written and verbal instruction.

The message of my experience is plain – with any emergency aircraft procedures, make sure you know what the words mean, if necessary checking out exactly what to do with a licensed engineer experienced on that system. Darkness and failing electrics hardly provide the ideal environment in which to discover your lack of familiarity with your aeroplane!