Conspiracy theory

8897

Name withheld by request

Conspire (verb) of events or circumstances, seemingly to be working together to bring about a particularly negative result.

That word conspire went through my head for days after this particular close call. It did so because it accurately described an accumulation of factors leading to the incident. And it also helped me shift blame away from things I could have done, and back onto the events themselves.

It was a blisteringly hot day in the Sydney basin. The forecast said it was due to flirt with 40 degrees by late afternoon, and it was already climbing towards the mid-30s as my passengers and I headed out to our Piper Cherokee at Bankstown. The plan was for a scenic flight to Katoomba and the Three Sisters, before returning to Bankstown via Camden.

We were heavy; 3 POB, full fuel, and some hefty camera bags to add to the mix. Knowing this I diligently completed the weight and balance and performance charts, to find out we were just within limits. With flight plan in hand we headed out to the aircraft, and I enjoyed showing my passengers the walk around.

The departure from Bankstown was uneventful, and I soon relaxed as we set course for the Blue Mountains. The Three Sisters appeared, and water was glinting in the sunshine as it cascaded down the magnificent Wentworth Falls. It was one of those moments you relish as a pilot, when your passengers are beaming at the experience you are giving them. With photos complete we set course for Camden, planning a touch-and-go before heading home.

As we descended back into the Sydney basin, my thoughts turned to the Camden approach. It’s always impressive for passengers if you fly the low-level entry to the zone, following the river, and then a touch-and-go on runway 10 which is grass. I thought about the climb performance we had achieved at Bankstown and decided that the short-grass runway at Camden would present no problem, especially during a touch-and-go. So it was this I requested from ATC, and my wish was granted.

Now that we were down low, it was clear that it had become more turbulent since leaving Bankstown. We passed through areas of rising and descending air which required active altitude maintenance, and my passengers were noticeably quieter than they had been before. The approach looked great until about 300 feet, when we entered a smooth, wide thermal. It wasn’t as rough as the others, almost imperceptible as we first entered it, but steadily it reduced my rate of descent and the grass runway appeared to fall away beneath me. No problem I thought. Reduce power to idle, lower the nose to maintain airspeed, a little sideslipping, and we were almost back on the ideal descent path. Almost.

We landed long, floating more than I would have liked, and eventually touched down a few metres to the right of the centre. Regain centreline, flaps up, full power and we began our acceleration once more. Slowly. Perhaps too slowly? I looked at my ASI and the needle was creeping clockwise. Not so slowly that I thought about aborting the take-off, but it was slower than felt comfortable, or perhaps normal. Finally, after what felt like an eternity, we hit the magic 60 knots and I squeezed back on the yoke, teasing the Cherokee into the air.

To say that the climb performance was below-par was an understatement. I checked my airspeed—79 knots for best rate of climb—and looked ahead to the end of the runway and the trees beyond it which were getting bigger by the second. Why is the performance so different to that I had at Bankstown? I couldn’t understand it. I checked the throttle, ramming it against the stops, and realised that I now had to establish best angle of climb if I wanted to avoid turning the three of us into a statistic. I raised the nose to the correct attitude. The airspeed reduced to 63 knots, and only then did I dare to look out to my left to see the tops of the trees next to the Nepean river pass by about 50 feet below us. I can remember seeing a tinny on the river, and being able to make out the name on the front of the boat. That is how close we were.

Once more my eyes scanned my instruments for any sign of trouble, and then I saw it. Carburettor heat ‘on’. My heart sank. I reached down and flicked the lever back up, and immediately things improved; the engine tone picked up and the rate of climb improved. I couldn’t believe the difference that an extra 100 RPM was making on this marginal day. As we climbed away and set course for Bankstown, I began to see how it happened.

The approach was normal until 300 feet, and then the smooth, fat thermal began to conspire against me. The thermal must have chosen that specific point as it knew that I always do my final checks at 300 feet; the checks when I turn my carburettor heat off. On any other day I would not have ended up with such a reduced safety margin, but the density altitude was also conspiring against me. The aircraft had conspired against me too, choosing this particular flight to be close to MTOW. Then the runway conspired against me, being short in length and with a surface of grass, adding to a take-off roll that was already extended due to the float on landing, conspiring against me …

It took a few days for me to realise that the only real conspiracy theory was in my mind. As I mulled over my close call that day, it was becoming clear that every single one of those multitude of factors was manageable. I should have planned more carefully before requesting a short-grass runway on a hot and humid day. I should have gone around early, rather than continue with an unstable approach. I should have initiated a best angle of climb sooner that I did. And I shouldn’t have allowed myself to be distracted from those critical 300 foot checks.

There is a quote which says, ‘conspiracy theories are the refuge of the disempowered’. While this incident was a valuable lesson in how a multitude of different threats and errors can quickly escalate into an undesired aircraft state, the biggest lesson of all was coming to terms with the fact that I was empowered to manage all of them better.

10 COMMENTS

  1. As always a combination of things to cause a problem. Excellent article. Interestingly, the Cherokee POH calls for carb heat only when carb icing indicated, not as a routine. I suspect at 40C, there was no indication of carb icing. First error, be familiar with the operation of the aircraft.

  2. Too true to the poster above, amazing those that shouldn’t have ticket to drive a lawn mower!!. The problem started way back then this driver did his last bi-annual. He obviously is of low experience, there was the first hole in the cheese. Second the tester from his last chk should have been more thorough. I’ve seen this too many times. A BFR (or whatever new feel good word there is for it) doesn’t test the pilot properly, to many under the table passes goes on in this industry and CASA are clueless!!. Too many slip thru the net like this guy who could have easily cancelled the tickets of a few human beings that day. Biggest sign here was the heat!! Why the hell would you want/need to do flying amongst the hills during the heat of the day in a gross loaded under performing SE plane? Big mistake. The beauty about Pvt. flying is you don’t have to go! If you must go do it at sunrise, spectacular time anyway!
    This goose was lucky, this time! I hope those Pvt drivers reading this take note!

  3. Don’t behead the man please. Look at the system. If not him, someone else may. Thanks for the share. Lots of learning value.

  4. I disagree with Richard – applying carb heat only when us mere mortals believe climatic conditions require it is just asking for trouble. No matter what the POH advises, apply carb heat at every reduction from cruise power. Just remember to remove carb heat, prior to asking for full power, particularly when other factors are “conspiring” to make very hp count..

    • Humidity can have a huge effect and does not have to be even very cold sometimes carbicing can happen at very inopportune moment s it is ice in the carbie and the formation dui to the pressure reduction in the throat and humid air

  5. It takes self-realisation, humility, time, and a genuine desire for all of us to learn from others’ mistakes, to contribute an article like this author. To describe the author as a “goose” or suggest he/she lacks competence reflects poorly on Walter….unless of course Walter has never made a an error.

    Thank you author. As a medium hour, 25 year PPL, I learnt from your article.

  6. Good article, especially for the purpose of this forum. Hindsight and reflection on factors leading to potentially negative outcomes is how we learn. Richard’s comments are valid, whereas Walter’s are why author’s names are ‘withheld by request’. It is easy for master pilots who have never made a mistake. Please don’t discourage people from relating their experience for our benefit.

  7. Thank you for this article. Yes we all learn. I suspect behind his insulting ways even Walter may learn. Walter uses Prof James Reason’s swiss cheese model who also notes that the worst accidents happen to the best people. Maybe Walter is not as good as he suggests he is and so we have to wait until he makes his big mistake.

  8. It takes a certain degree of courage to share a story like this, and I greatly appreciate the author doing so. I learned something that hopefully I will not have to learn through personal experience.

    I do not think this is an appropriate forum for the sort of criticisms that have been made, as it will only discourage people from sharing their experience – and if that happens, we all lose an opportunity to learn.

  9. Can Walter write an article on his perfection and truthfully state he has never made a mistake in his time flying? His horrible comments contribute nothing towards pilots learning from the mistakes of others.

Comments are closed.