Plane Truths and Knee-jerk Reporting

beaverNow that the wreckage of the Beaver floatplane has been fished out of the waters of Jerusalem Bay, in Sydney’s Hawkesbury River system, it will be only a short time before the Australian Transport Safety Board investigators determine that the plane stalled at a low level and went into an incipient spin. The crushed noses of the two floats indicate that the Beaver dived almost vertically to the bottom of the bay. While the front of the plane including the cabin has been crushed, the rear fuselage and tailplane are almost intact.

There’s nothing like an air accident to reveal the ignorance and lack of experience in what passes for daily journalism today.

A clutch of ABC tyros repeatedly referred to the crash as a ‘ditching’ – the technical term for a pilot setting an aircraft down on water in an emergency as carefully as possible.  But that was eclipsed by a Channel 9 report that had police divers hoping to recover the ‘black box’ – a device not carried, or required to be carried, in such a light aircraft. The Guardian reported that Sydney Seaplanes had been operating joy flights for eighty years.

When the Sydney Morning Herald turned up the fact that the floatplane, registered VH-NOO, had been written off as ‘destroyed’ 21 years ago when in its previous incarnation as a crop-duster landplane, VH-IDI, it was the signal for the ignorant to pontificate about the dangers of ‘old’ aeroplanes. ‘Destroyed’ in the ATSB summary merely meant that the plane had suffered substantial damage when it flipped onto its back and was no longer airworthy. It was certified recoverable by an aeronautical engineer, and was neither too difficult nor expensive to re-construct to certifiable condition.

What is more than likely is that aircraft in the Sydney Seaplanes fleet of Beavers and Cessna Caravans were maintained to standard and as good as new for the light duty sight-seeing tasks they are called upon to perform. From witness descriptions, engine failure and aircraft break-up in mid-aid could immediately be ruled out as causes of the accident, which claimed six lives.

The dive to the water immediately after making a banking turn to the right strongly suggested a stall common to the Beaver type.

beaver II

Like the venerable DC-3 Dakota of even greater vintage, the Beaver has had an enduring place in civil and military aviation. Designed and built by De Havilland Canada as a rugged short-take off and landing (STOL) aircraft for the Canadian outback, the Beaver quickly earned its place worldwide. A total of 1,657 planes were built, and 980 of them were supplied to the U.S. Forces. Some went also to the British Army before production ended in the mid-1960s. VH-NOO was among the last off the line, first taking to the air in 1964.

In any air accident, the place to start is with the flight manual, often referred to as pilot’s notes. The manual sets out all the specifications, dimensions, fittings and instruments of the aircraft — and, importantly, advice on its flying characteristics. For the Beaver, the relevant numbers specify normal operating speed limit is given as 243kph, landing speed of 72kph and stalling speed with flaps up (as in normal flight) of 96kph.

Paragraph 4.11 helps to explain the Beaver’s popularity with pilots and why hundreds remain in use:

“Stability is good about all axes. The aircraft is easy to fly and is docile down to the stall. Controls are normally effective throughout the airspeed range. The aircraft can be trimmed to fly hands-off from climb to maximum speeds.” 

But there’s a warning in Paragraph 4.11.5:

“The stall is gentle at all normal conditions of load and flap and may be anticipated by a slight vibration which increases as flap is lowered. The aircraft will pitch if no yaw (sideways swing) is present. If yaw is permitted, the aircraft has a tendency to roll. Prompt corrective action must be initiated to prevent the roll from developing.”

As every pilot knows, there is an inherent relationship between speed, angle of bank and the load factor the airframe can withstand. The tighter the turn, the greater the angle of bank has to be, the more stress on the structure, particularly the wings. But because the wings are no longer horizontal, the lift generated by the inner (lower) wing is reduced, and that wing may stall. The Beaver Manual gives pilots a neat table which warns to beware of steep turns.

What it all means is the steeper the turn, the higher the speed has to be to avoid a stall. And as both increase, so does the load factor, which may reach the design limit for the plane.

When Nat Nagy, director of the Australian Transport Safety Bureau, was interviewed on television, he was at pains not to draw comparisons with other Beaver accidents. But there is no doubt this is one of the first things his investigators will look at. They will know, as I was soon able to learn, that in Canada there were twelve similar accidents in which Beaver floatplanes stalled, spun and crashed. A total of 31 people lost their lives and another 19 were injured.

The most recent accident, in August 2015, was analysed in great detail by the Transportation Safety Board of Canada in Report A15Q0120.  This summary quote seems apposite to the Sydney Seaplanes crash:

“In the controlled conditions of certification, the stalling of the DHC-2 was described as gentle. However, as is the case of many other aircraft, a stall in a steep turn under power triggers an incipient spin with few or no signs of an impending stall, and the flight path changes from horizontal to vertical. In low-altitude flight, stalling followed by incipient spin, no matter how brief, prevents the pilot from regaining control of the aircraft before impact with the ground.”

It’s only fair to point out that in the Canadian accident cited above, the pilot lost control while circling at a dangerous and illegally low level at a spot where a family of bears had been seen  All indications are the Beaver that crashed into Jerusalem Bay was only banking, and not necessarily steeply. The questions to be answered relate to the speed and power setting for the angle of bank.

In their investigation, the Canadians had the benefit of the pilot’s GPS device which had recorded the position of the aircraft every five seconds on the last twenty flights he had made. From it, they were able to construct a three-dimensional graph of the flight, and calculate his likely angle of bank. They were also able to compare his fatal flight with previous trips.  They found he had flown almost exactly the same route many times before; only the last time he banked a little too steeply, and stalled.

So one of the critical things for a pilot to watch in his turns is his air speed. The airspeed indicator in a Beaver is a dial in which the needle moves clockwise from zero mph at the 12 o’clock position to 250 mph at 11.30. But the gradations are not evenly spaced. For most of the instrument, there are marks every 25 mph, but between 0 and 75 mph the gradations are compressed. This makes it difficult to easily read speeds in the critical stalling zone. Several observers have commented on this and asked if it contributes to a pilot’s lack of awareness of his speed.

Several public statements have appeared to the effect that the investigators hope to recover video or photography from the passengers’ phones, but this is unlikely to help. What they will be looking for include: the position of the flaps (flaps are lowered for takeoff; if still down, they reduce the risk of stalling in a turn); the needle of the turn and bank indicator; the reading on the airspeed indicator; the throttle setting and any GPS recording. They may also try to find where the passengers were seated; three of them were heavy men who could have affected the centre of gravity if sitting in the rear seats.

In 2009, the U.S. Federal Aviation Administration (FAA) suggested that the Beaver’s stall characteristics in an “aft CG “(centre of gravity) condition are unstable and unpredictable, and that what it called ‘flight excursions’ with an aft CG are often unrecoverable at low altitude. These, and many other clues will give the ATSB much to work on to determine the cause of the crash.

Geoffrey Luck, a pilot and former ABC journalist, wrote memorably in 2014 for Quadrant Online of his own brush with death as a novice aviator. Follow this link to his memoir, Down to the Wire

  • [email protected]

    What an adventurous life! Is there anything Geoffrey Luck has not done? From drilling tunnels in the Snowy Mountains to novice aviator he had the endurance to survive as an ABC journalist and retain his common sense.

  • ianl

    Thanks Geoffrey – informative and concise, as I respectfully wish all factual reports to be.

    Given your journalistic background and experience, are there any actions you know of that may dampen or mute the tendency of the MSM to publish speculative, ignorant rubbish and so misinform the equally unknowing public ? Completely removing that tendency is mission impossible; Murdoch (I think) voiced the aphorism that there is no requirement for the MSM to educate the public, so of course they don’t.

  • Geoffrey Luck

    ianl – The problem is that journalism today is populated by bimbos and beardless youths, fresh out of university studies of politics and sociology. In television they are trained principally to recite police facts or a public relations handout in a piece to camera without fluffing. There are no old journalists to supervise their output, no sub-editors, and no other way of imparting knowledge or wisdom. The public is thus condemned to perpetual juvenile amateurishness in any story more complex than a shark attack. And that will be distorted by concern for the shark!

    • ianl

      I rather feared that as the truth. And yet they are paid in 6 figures, with some aspiring to 7.

      I was thinking of the episode you described losing a drillhole in Snowy 1.0. I’ve lost more than I care to count – once, stubbornly, I lost three (3) drillstrings 350m down in a row on a China project before I finally admitted I could *not* drill that fault zone. The exploration budget suffered quite some damage from that, as did my geoscientific ego … oh well.

      • Tricone

        350m? That’s a post hole to me!

        Not that any journalist these days would come anywhere near a driller when doing a scare story about drilling. I guarantee a Green party member or proxy will be first and last person to speak on camera other than the “reporter”.

  • [email protected]

    It’s not a new phenomenon. I have twice been directly involved in accidents/incidents which, more than 50 years ago, were reported in the MSM, once in the tabloids and once by the ABC. In both cases, the reports got every salient detail wrong, including my name. After a career in the ADF, the Australian media has consistently misreported almost every single matter with which I had any personal familiarity. The best advice I ever received was never to believe anything you hear and only half of what you see.

    • Jody

      My son worked as a journalist before going into politics. He said the major news outlets largely stole their ‘news’ stories from other journalists and newspapers. He regularly had Channel 9 and the ABC phone him about a story he’d written. He quickly became bored with journalism.

    • Druemac

      That may leave you one eyed!..but yes a very good article

  • Tony Tea

    Michael Crichton’s novel, Airframe, is all about an air incident and is an excellent read.

    • [email protected]

      Great book.

    • [email protected]

      Michael Criton! An opportunity to remind everyone about Michael Crichton’s comment on the Gell-Mann Amnesia effect.
      Very apposite in this case:

      “Briefly stated, the Gell-Mann Amnesia effect is as follows. You open the newspaper to an article on some subject you know well. In Murray’s case, physics. In mine, show business. You read the article and see the journalist has absolutely no understanding of either the facts or the issues. Often, the article is so wrong it actually presents the story backward—reversing cause and effect. I call these the “wet streets cause rain” stories. Paper’s full of them.
      In any case, you read with exasperation or amusement the multiple errors in a story, and then turn the page to national or international affairs, and read as if the rest of the newspaper was somehow more accurate about Palestine than the baloney you just read. You turn the page, and forget what you know.”

      Journalists with incurious ignorance on every page.

  • [email protected]

    An excellent article by someone who has done some easily available research, but if a journalist did the same research they would not have the story the beardless editor asked for! The Grumman which crashed into the Swan last year was doing the same thing, a low speed steep turn. Now at thirty thousand feet, this would not be a problem, but with no air under you!

  • Doc S

    Banking or doing a turn at low or insifficient altitude and low or insufficient speed resulting in a stall is pilot error. An aircraft with known propensity for stalling at low speed is a technical fault or limitation of the aircraft design but the combination of both is a certain recipe for disaster and well known since the beginning of aviation. These are facts readily discernable to even the most incurious and pedestrian of journalists. It shouldn’t take a veteran journalist with experience and knowledge of aviation such as Geoffrey Luck to spell it out but such is the parlous state of journalism today that its the only way anything factual actually gets reported (i.e. virtually never). Pity the ABC (or any other media organisation for that matter) no longer appear to have journos of Geoffrey’s calibre.

  • [email protected]

    I was a pilot and from the initial description from a witness in one of the first reports, I came to the same conclusion as you, as would most pilots I recon. I have always found the media deficient in their lack of understanding of air crashes and I I found your description of journalists spot on.
    Thank you for the detail.
    Andrew McIntyre

Post a comment