BRISBANE VALLEY FLYER November- 2020
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35 785 BRISBANE VALLEY FLYER November- 2020 www.wattsbridge.com.au www.bvsac.org.au Watts Bridge Memorial Airfield, Cressbrook-Caboonbah Road, Toogoolawah, Q’ld 4313. Rob Knight (Editor) Tel: 0400 89 3632 Vintage Aircraft, Fleet 2, built 1928, attending Watts Bridge Vintage Aircraft Fly‐In. Peter Ratcliffe (Pres.) 0418 159 429 Ian Ratcliffe(Treasurer) 0418 728 328 Vern Grayson (Vice Pres.) 0431 465 874 Jackie Daley (Secretary) 0438 783 740 - Brisbane Valley Flyer - From the Club Pre Covid‐19 Hello everyone, Just a couple of notices this month. Note that they are quite important so be sure that you take a note of them. Notice ‐ 1 Please be aware that the next BVSAC Meeting will take place on the Second Saturday of November i.e. on the 14th of November at the usual time. Notice ‐ 2 The BVSAC Christmas Party is scheduled to be held on the second Saturday in December. That date being the 11th of December. All the best Peter Ratcliffe BVSAC President Page 2 Issue 86 November – 2020 - Brisbane Valley Flyer – The Improbable Turn By Rob Knight WARNING: this article is blunt. I am not PC, and i am certainly not softening my prose. I need to get a message across that just might save your life in a moment of high stress. The name of this article says it all. If you attempt to turn back to land on the departure runway subsequent to an engine failure after take‐off, especially at low altitude, statistically your very survival is improbable. I was totally dismayed when I recently read an article published in an aviation journal promoting a 180 degree return to the runway following an engine failure after take‐off. The writer advocated that pilots experiencing an EFATO1 to seriously consider turning back to the departure runway as an alternative to restricting their choice of landing options to an arc ahead of the aeroplane. If the article had been presented as one man’s opinion/suggestion, a man who is a professional pilot, very experienced, and with substantial resources to examine the action and operate under an umbrella of pre‐ planned and controlled circumstances. I would have found the piece much more relevant and, perhaps, even an acceptable point of view. But it wasn’t and I don’t because it wasn’t. It was a pilot with no apparent instructing experience who had not seen how people handle stress under pressure, using statistics to make his point of view and lecture others on his flawed logic. Such logic that could/would cause a fatality that may not otherwise occur. In other words it was BS. A real EFATO is, perhaps, the worst nightmare of every pilot. The aeroplane will be heavy, short on altitude and ultimately short on time because there will be up to 5 seconds of bewilderment and delay as the realization of what has happened sinks in and the first remedial action undertaken. An EFATO is really an exercise in time management ‐ the aircraft is low, and slow, (and will get slower until a corrective nose attitude can be achieved). The success (or otherwise) of a real EFATO depends entirely of the efficient use of the time available before the aeroplane descends onto the ground. From the pilot’s seat, by the time of total realization that the engine has failed has sunk in, the high nose attitude without power will have robbed the aeroplane of considerable airspeed and the nose attitude must substantially change to maintain airspeed. Pilot’s as humans have a primeval urge in threatening situations to return to their last place of safety and, this being behind them and on the runway, pushes the instinctive reaction button to turn back to safety. While in a very, very few circumstances this may be possible, the actual occasions where it is appropriate are miniscule in number, and there are libraries of statistics dictating the failures to achieve this are almost inevitably fatal. The reasons why, in theory, a turn‐back which might be achievable in theory is not likely to succeed in practice lie in our own very human frailties. The several seconds delay in our recognising a problem and then responding is a time delay and, as stated above, time is short. Also, under the stress of the situation, the precision flying needed to carry out a successful turn‐back is unlikely to be available under that stress. 1 Engine failure after take‐off. November – 2020 Issue 86 Page 3 - Brisbane Valley Flyer - The virtually inevitable result is not a safe landing, but a successful low‐altitude, non‐intentional descending turn stall/spin instead. The extremely steep nose attitude needed to maintain speed in a tight, steep descending turn is not something many pilots anticipate at that instant, and almost all pilots that I have flown with would be reluctant to see the windscreen completely filled with the world as will be required. With the unexpected visual appearance of the attitude necessary to carry out the step descending turn, slip or skid is often not recognised, and any example of either will further increase the danger of the manoeuvre. I have been informed by the uninformed that it’s merely a matter of wind, or more specifically, a strong headwind component, when the failure occurs that decides on the success or otherwise of a turn‐back. Right? Even if there is no tailwind on the runway, the airspeed at the flare will NO, It’s WRONG! still be raised by the factor of the gradient experienced. In most cases a strong headwind will see the aeroplane with a shorter return distance to the runway because of an increased angle of climb in the wind gradient. But, but, but ‐ this will be more than offset by the higher ground speed the aircraft will have on its return, and, if a gradient is indeed present, the airspeed control issues that this will raise will need addressing. See the September 2020 issue (No 84) of the BVSAC Flyer for the effects of wind gradient on airspeed. To prove these points for myself, in 1974, whilst a line Instructor at the Waitemata Aero Club at Ardmore, New Zealand, Maurice Parsons, another instructor and I took out a Victa 100 to experiment. We hoped to ascertain a reasonable minimum height necessary to achieve a successful turn‐back after an EFATO. Our findings were that, for us, two professional pilots, experienced, and very current on type, we needed to be at least 400 feet above the runway elevation to have any chance of successfully returning to the runway at all. The two primary issues were: 1. Not wasting altitude achieving the nose attitude to maintain the required 70 kias, and 2. Actually getting the nose down far enough to achieve to maintain that speed during the turn. We found that the whole windscreen had to be filled with ground to maintain 70 kias in the steep descending turn necessary to get back to the runway and, for students and PPLs at least, this was likely to be too intimidating for them to realistically achieve. Thus, any attempt below at least 400 feet above the runway literally doomed the aircraft and its occupants. We settled on teaching no turn‐back on climbout below 700 feet above the runway. Once established on the crosswind leg, a return to the runway was as safe as any other field selected at low level because of the extra altitude and the reduced heading change required to return to the runway. We also tried it in a PA28‐140 with similar results. I must add, though, that we did the Cherokee testing with just the two of us in it for safety reasons, but agreed that the turn‐back on climbout was to be discouraged and was only to Page 4 Issue 86 November – 2020 - Brisbane Valley Flyer – be carried out after turning crosswind. This would be safe and quite appropriate for that aircraft type based on our experience on the PA28 with a full load. Conventional pilot training takes into account the shortage of time available to respond to the recognition of an EFATO by deliberately overlearning the procedure to adopt in the event of its occurring. The purpose of overlearning is to produce an automated reaction that best uses the time available by minimising delays after the initial surprise or shock of the failure and enhancing the decision‐making process. This, once the realisation has sunk in that a real EFATO has occurred, the subsequent actions are delivered from rote learning and no thought process is required. There is no time for a written checklist, and no time to even think about it. Just time for a set of practiced actions. As a retired professional pilot, I believe that it is a better decision, in most circumstances, to make a controlled landing onto less than hospitable terrain, than to run the risk of stalling and spinning in an attempt to return to the runway should my engine fail after take‐off. In my flying life I have had three EFATOs. As an instructor, one failure was the disconnection of the carburettor heat cable in a Cessna 150 and ZK‐CSW could not maintain height with two up and full tanks with the resulting over‐ rich mixture. I did not turn back – I landed on the cross runway. The second was in a Piper PA38‐112 Tomahawk ZK‐PAH where we noticed the mechanical fuel pump had failed before there was any change in the engine. When the electric pump was turned off at 300 feet in the climbout we saw the pressure drop on the fuel pressure gauge.