THE WAIT

I have a clock. It has been six days and nights since I was last chained down and my controls locked.

I don’t like being chained down. I don’t like the nightly condensation. Moisture beads over my skin and seeps into little cracks, causing powdery corrosion where it sits. The steel cables running from my cockpit become rusty, as do the hinges holding the control surfaces to my airframe. My electrical connections degrade and can suddenly fail in flight. Even the main spar running inside my wings can be fatally weakened by prolonged condensation.

More insidiously, each day/night cycle adds more moisture to the internals of my engine and to my oil. A cold mist coats my moving parts, leading to pitting and microscopic cavities.

The corrosion has three bad effects on my engine – surface wear, structural weakness and parts sticking together.

Firstly, surface wear. My cam lobes corrode; then the valves don’t seat properly and my engine loses power. My once-shiny cylinder walls and piston rings become scaled with rust and don’t seal anymore, further reducing my engine power. Corrosive gases penetrate past the worn rings and dissolve into my oil reservoir, becoming new agents of corrosion. Oil blows past the other way and disappears into thin air with the exhaust, compromising the constant swash of lubrication and cooling essential to my ongoing health.

Secondly, corrosion causes structural weakness. One of my tappets might fail, causing the valve to get out of rhythm with the engine or even worse, force the pushrod out of shape, leading to total loss of power in that cylinder and other damage.

Thirdly, parts stick together when they get rusty. One of my valves might become stuck, get too hot and disintegrate, the bits getting sucked into the cylinder, the upwards stroke of the piston suddenly curtailed as it strikes the trapped metal fragments near top dead centre, causing the connecting rod beneath to snap in two, which leads to a catastrophic cacophony of whirling metal within the crankcase. Within seconds, my engine is destroyed.

To minimise engine corrosion, my powerplant needs to run hot for at least an hour a week so that it can burn off all the accumulated moisture.

UNCHAINED AT LAST

After six days and nights, I am glad when at last the chains are run out of my tie-down points. It is not yet midday by my clock, yet my aluminium skin is radiating heat.

The little shroud slips off my pitot tube. A familiar weight steps up onto my right wing. Canvas slides off and there’s an instant blaze of radiation onto my Perspex. The weight steps off and my side luggage door is opened. Three heavy shapes land on the carpeted floor before my luggage door is closed and locked again. I am not used to having so much weight in my luggage area. I am leaning uncomfortably backwards. The main weight steps back onto my wing and the cabin door is opened. The weight settles onto one of my front seats.

My storm window is unlatched. The pitch trim wheel is run all the way back and forward and then set back to the neutral position. My lateral trim wheel is spun right and left and back again. My master switch and pitot heat are both turned on. My electric gyro starts spinning up, all three undercarriage lights show green and my fuel needles flicker across the gauges.

The weight lifts off the seat, moves out of the cabin and steps off my wing for the second time. After a brief delay, the stall warning tab out on my wing is moved up and down and my stall warning audible alarm squeals in response. Then I feel a brief cool touch on my pitot tube under the left wing. The weight returns to my cockpit and my pitot heat and master switch are switched off again. The flap handle is hoisted three clicks so that my flaps extend forty degrees down.

The weight exits my cockpit. The flaps on the right wing are pushed down to the stops and released. My ailerons are exercised up and down from the right-side and my controls react in the correct sense. Up-towards, down-away. My airframe is rocked forward and aft from the wingtip. My fuel drain is operated. The right fuel cap is unlatched and a small amount of fuel returned into my right tank before being closed up again. The oil filler cap is raised. My dipstick is unscrewed and lifted before being returned and screwed back again and the filler cap snapped back into place.

The touch runs along my propeller blades. My alternator belt springs back after being pressed. The fuel, ailerons and flaps are exercised on the left side as they were on the right. The trailing edge of the horizontal stabiliser on my tail is tilted up and down. My controls react in the correct sense. Up-back, down-forward. My vertical stabiliser is pressed to and fro.

Now two new weights climb onto the wing, one by one, and push down on my two rear seats. The original weight climbs in, followed by a second and heavier weight. These two weights settle themselves into the front seats. The combined weight in my luggage area and on my four seats adds up to a discomforting amount of downwards pressure on my main wheels, my fuel tanks being full also. My side door is pulled shut and latched. The seatbelts are run out and clipped fast. My brake pedals are pressed down.

START

My master switch is turned on. Then the booster fuel pump. My throttle is opened wide and the mixture lever moved from lean to rich, held there for a couple of seconds while a squirt of priming fuel enters my cylinders before the mixture lever is moved back to lean. My throttle is returned to the idle position. The key turns and my starter cranks.

My magnetos deliver 20,000 volts to the spark plugs, igniting the fuel and driving my four pistons into a continuous blur of motion within the cylinder block, the lobes of the overhead camshaft pressing the pushrods out against their springs to open the intake and exhaust valves at precisely the right moment in the combustion cycle, a thousand times a minute. The connecting rods translate the up-and-down motion of the pistons into rotating my crankshaft and my propeller spins, the stream of air providing welcome relief to my hitherto rapidly warming Perspex cockpit and hot fuselage skin.

Upon starting, my mixture lever is open fully rich and my throttle trimmed down to 1000rpm. My booster fuel pump is turned off, with my engine-driven pump now doing the work of delivering fuel from my left wing tank into the cylinders. My radios are turned on and my autopilot flicked into test mode. The altimeter and directional indicator are set. A finger runs along the two rows of electrical fuses – all are correctly indented. The test button for my three red annunciator lights is briefly pressed. My autopilot is tested with a sequence of button pushes, my controls moving obediently via the servo motors. My fuel booster pump is cycled while the fuel selector is moved from L to R so that fuel is now being drawn from the right wing tank. My engine keeps running without interruption and I am reassured that both left and right fuel lines are clear. My cabin is getting hot and the ventilation fan is set to full speed.

TAXI AND RUNUP

The pressure on my brake pedals releases, the throttle is pushed forward but nothing happens. The throttle has to be pushed wide open before the warm ground begins slowly rolling under my overloaded tyres. The rudder pedals are jockeyed back and forth, my nosewheel turning as commanded.

After a couple of minutes, pressure returns to my brake pedals causing my brake pads clamp down on the brake disk and the ground to stop rolling under my tyres. My storm window is closed. The booster fuel pump is turned on. The pressure on my brake pedals increases and my throttle is advanced until my engine gauge shows 2000rpm. The alternate air lever is cycled down and up. My mixture control is leaned back until my engine rpm drops then restored to the fully rich position. My propeller pitch control is cycled three times, with warm oil flowing back and forth through my constant speed controller and my propeller blades biting off more or less air, the rpm slowing down and speeding up in response. Each set of magnetos is switched off and back on in turn, with my engine speed dropping by less than 100rpm in each case. My throttle is moved back to idle, then set to 1000rpm. My control stick is fully exercised – left and right, forward and back.

The push-to-talk radio button is pressed. The pressure on my brake pedals disappears, my throttle is advanced – advanced some more – advanced to full – before I eventually feel the gritty ground moving under my wheels again. The ALT button on my transponder is pressed and my wingtip strobes are turned on.

TAKE-OFF

My wheels bump onto a new smooth surface and the rudder pedals swing me through ninety degrees. I have never felt so heavy. The air is hot and thin.

I wish the mixture control was pulled back, it is set too rich for the low density air. I know that with proportionately so much fuel in the mixture, my combustion will run out of oxygen on each cycle and I won’t be able to reach full power.

The throttle is pushed fully forward and, after a pause, the smooth surface starts to roll slowly underneath my tyres. The weights are all pressing down on my seats and luggage compartment floor. My engine labours under its overly rich mixture. My wings don’t produce as much lift as normal because of the thin air. My tyres begin to rotate faster but not yet fast enough for takeoff. My control stick is pulled back and I briefly lose contact with the smooth surface, only to fall back heavily. I cannot yet support myself in the thin air. I am too slow. After a few seconds, my control stick is pulled back again. Again I cannot support myself. I fall back and continue to roll, seemingly forever. I need more speed. On the third attempt, I lurch upwards and manage to perilously support myself on a cushion of air just above the surface. I need to be kept there for a few seconds more to gain enough speed to climb. But the control stick is suddenly jerked upwards again. My propeller and wheels are struck with an onslaught of small impacts. Mercifully this ends as quickly as it begun.

But my speed has been reduced by the impacts, there is too little lift and I cannot keep flying. I suddenly pitch forward and drop down, my left wing dipping in a stall. Within a few seconds, this wing is struck with tremendous force and snaps off. My fuselage starts to cartwheel left before being struck by the same hard surface. The shockwave ripples through my whole frame, causing my fuselage to concertina and buckle. My engine comes to a sudden stop, the propeller surrounded by inert matter. My instrument panel is thrown awry and the front seat weights smash into it. The luggage weights fly forwards and smash the rear seats down on top of the rear seat weights. My right wing is brought to a sudden halt and my tail folds in half as the force of the impact reaches my rear. Fuel is pouring out both wings. A second huge shockwave strikes all my stricken parts and I feel the intense heat of combustion happening where it shouldn’t – outside my engine. My plastics melt almost immediately. Then my outer skin starts to curl back from the intense heat. My spirit soars aloft from the incandescent fireball; I will never again be chained down.

ATSB Accident Report

Collision with terrain involving Piper Arrow III, VH-ABC, 540m east of Hot and High Airport, NSW on 1 April 2021

Investigation number: AO-2021-999

Summary:

The aircraft departed from Runway 10 with four people and three sets of golf clubs plus full fuel on board. It was on a flight to Ritzy Airport and the adjacent 18 hole golf course. According to eye witnesses, the take-off ground roll was noticeably long and involved three separate lift-off attempts before VH-ABC finally managed to climb to about 20 ft agl and appeared to stay in ground effect until an approaching treeline forced a further climb attempt which ultimately failed, the aircraft clipping the treetops before stalling and spinning into the ground. The aircraft rapidly caught fire. All the occupants of the aircraft died in the accident and the aircraft was destroyed.

Probably cause:

The probable cause of the accident was a failure to maintain control of the aircraft when in close proximity to the ground.

Contributing factors include:

• The aircraft being an estimated 130kg overweight, reducing aircraft acceleration and lengthening the ground roll needed to attain sufficient airspeed for takeoff.
• The high density altitude due to an ambient temperature of 37 degrees Celsius, further reducing aircraft performance and lift, thereby further lengthening the calculated ground roll to 1020m, considerably more than the 850m available.
• An out-of-limits centre of gravity caused by excessive weight in the baggage hold, reducing aircraft stability.
• The pilot’s apparent failure to take the above factors into consideration prior to departure.

What could have avoided the accident:

• Offloading the golf clubs (perhaps hiring golf clubs at the destination instead) as well as offloading some of the fuel to bring the total weight under maximum gross weight, whilst still having sufficient fuel to reach the destination including reserves.
• Departing earlier in the day when the ambient temperature was lower, thereby reducing the high density altitude effect on the aircraft performance.
• Leaning the mixture to compensate for the thinner air so as to attain the maximum engine performance available.
• Performing a shortfield take-off as per the manufacturer’s recommendations, with 2 notches of flap and holding onto the brakes until the engine had reached full power before releasing.