Swan river incident

[facthunter]

That aileron isn't going to help anything, and never would. It's over by then anyhow. There are no black boxes involved here . You might get something from any GPS that were carried. The position of the controls tells a lot. I always watch them when any aircraft is doing anything interesting. The various videos will provide the main info to investigate this unfortunate occurrence. We can only learn from it, now. A difference with a twin with wing mounted engines and fuel tanks in the wing is roll inertia . Harder to start a roll and harder to stop it .Nev

 

 

[Methusala]

The essential message here is to use the rudders. I have been involved in ultralight aviation for 35 years and have flown many types but all of them have been "low performance" and mostly tailwheel. Modern utility aircraft are designed to be easy and instinctive to fly. Differential aileron gives the pilot the idea that rudders are used on the ground to steer when taxiing. I know that this statement simplifies things a bit but I remember a female GA pilot who landed in a Grumman Traveller and asked whether she could do a circuit in the Thruster. Immediately after take off I became alarmed at her aircraft control. I asked her when she was going to get on the rudders. She exclaimed that she wasn't used to flying with rudders and would I do it for her. I quickly shouted,"my airplane" and completed the circuit. Every aircraft flies uniquely and requires correct technique to be operated safely. Air Force and airlines invest a lot of time and money in familiarising their pilots with the equipment. Don

 

 

[cscotthendry]

Sad, 10 news just reported he texted friends that he expected poor performance from the the aircraft due to the heat. It's probably hard to tell yourself on such a nice day that it's a no go. Horrible to watch and know it's not going to recover.

I think this is the secret to the incident. It was reportedly very warm that day (I heard 42 deg) and the loss of performance and increased stall speeds would have been insidious and hard to predict. Couple that with low level maneuvering for a landing or a touch and go and it wouldn't take much of a mistake, just a moments inattention, to take the aircraft out of the safe flight envelope. Also, on some of the video I've watched, it looks a little like the tail kicks up as though he was trying to tighten the turn with the rudder, just before the wing drops. I could be wrong with this, but if it is the case, coupled with the high temps, that could easily result in the dreaded base/final turn wing stall.

Whatever the cause, it's still a sad outcome for the loss of life and a vintage flying machine.

 

 

[Fishla]

Stall speeds don't change if our density altitude is higher (warmer temp) do they?

 

IAS stall speed remains the same. Our TAS has increased (and our groundspeed too) though.

 

The engines might not be developing as much power (though not sure just how much less such temperatures would cause).

 

Yes? No?

 

I know that the 4 H's (High, Hot, Heavy, Humid) reduces performance but I've not learned exactly how to quantify it...

 

 

[pmccarthy]

A factor not mentioned is the crowd lines for the display, which may have been both shorelines. If so, he would have been forced into a very tight turn, like getting caught in a valley.

 

 

[Captaincoop]

How would the flight path of the aircraft as depicted have taken him into low level windshear?There's a lot of opposite (right) aileron in there, and no rudder. As I said earlier, instinctive, but very detrimental if the aircraft is stalled. If it was a left engine failure the immediate application of right rudder would be expected too, as any multi-engine pilot would know. Yet there is none.

 

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My point is that ALL possibilities must be considered. Those are just some of the things that need to be looked at rather than making a decision based on just looking at the video (which of course will help) As a qualified air accident investigator, I can say that there are many things to be looked at besides the "apparent" obvious stall.

As for low level wind shear in the depicted photo, that is way past the point at which I am referring. I meant that it is one POSSIBLILITY that the aircraft encountered undershoot shear leading to the flight path in the frame you have chosen. Out of the hundreds of approaches I have flown into Perth, (in daylight) it is very rare I have not experienced low level overshoot and undershoot shear. The altitude at which the aircraft appears to stall looks to be 250-300ft if that. Right where the shear is common. The early info is the it was hot and gusty on the day.

 

As any multi engine pilot knows, full (or worse partial) engine failure on the inboard engine is very hard to recognise, particularly if there is strong drift at low level. At that level in a high drag aircraft, identifying the dead engine when already flying slowly in the few seconds he has may simply prove too late, particularly if the aircraft is close to VMCA and so far back on the drag curve.

 

I've have found it difficult to identify the failing engine at 200ft with full flap at approach speed, and that was on a straight in approach, in a turn it's even worse.

 

If , however, you feel you have the whole thing sorted, ring ATSB and see what they say

 

 

[Captaincoop]

Stall speeds don't change if our density altitude is higher (warmer temp) do they?IAS stall speed remains the same. Our TAS has increased (and our groundspeed too) though.

 

The engines might not be developing as much power (though not sure just how much less such temperatures would cause).

 

Yes? No?

 

I know that the 4 H's (High, Hot, Heavy, Humid) reduces performance but I've not learned exactly how to quantify it...

Quite right. Temperature affects take off performance (weight and or distance) but once airborne stall IAS remains the same. Engine power is decreased abut at low level like that there would still be plenty of power available.

 

 

[dutchroll]

As for low level wind shear in the depicted photo, that is way past the point at which I am referring. I meant that it is one POSSIBLILITY that the aircraft encountered undershoot shear leading to the flight path in the frame you have chosen. Out of the hundreds of approaches I have flown into Perth, (in daylight) it is very rare I have not experienced low level overshoot and undershoot shear. The altitude at which the aircraft appears to stall looks to be 250-300ft if that. Right where the shear is common. The early info is the it was hot and gusty on the day.

I know what Perth is like - I spend half my life flying in and out of it - but I honestly don't care who has done the most approaches.

He was filmed maintaining a roughly level, tight-ish turn over the Swan River until the point control was lost. If you can explain how that'll put you in undershoot shear I will have learned something today.

 

If , however, you feel you have the whole thing sorted, ring ATSB and see what they say

Why on earth would I do that? I'm not trying to substitute myself for the investigation. I'm simply stating observations and suggesting a highly probable cause. Yes, that could be wrong, but if you're a qualified accident investigator you'll know there are very few accidents worldwide fitting this description and set of circumstances which are not simply "pilot lost control of aircraft with insufficient altitude to recover". There may be contributing factors of course.

By the way, yesterday an ATSB spokesman stated they already "had a good idea of the crash cause" - and they haven't done a detailed wreckage examination yet. Their words, not mine.

 

 

[Captaincoop]

I know what Perth is like - I spend half my life flying in and out of it - but I honestly don't care who has done the most approaches.He was filmed maintaining a roughly level, tight-ish turn over the Swan River until the point control was lost. If you can explain how that'll put you in undershoot shear I will have learned something today.

 

Why on earth would I do that? I'm not trying to substitute myself for the investigation. I'm simply stating observations and suggesting a highly probable cause. Yes, that could be wrong, but if you're a qualified accident investigator you'll know there are very few accidents worldwide fitting this description and set of circumstances which are not simply "pilot lost control of aircraft with insufficient altitude to recover". There may be contributing factors of course.

 

By the way, yesterday an ATSB spokesman stated they already "had a good idea of the crash cause" - and they haven't done a detailed wreckage examination yet. Their words, not mine.

I just don't think we should condemn the pilot before the facts are known. Yes it may well be what we all suspect, but at least give the poor bugger the benefit of the doubt.

I don't follow what you are saying re windshear? It occurs at any level as you know, and if one were flying low and slow near the stall then undershoot or a sudden loss of airspeed is going to tip the scales against you? Unless you mean you have to be changing altitude to encounter windshear? Im sure you would have encountered undershoot shear (be it straight and level or even in tightish turn) on a windy day?

 

 

[Garfly]

Every stall spin tragedy (whether this be one or not) reinforces the recent call from the FAA, and others, for small plane operators to consider installing angle-of-attack indicators.

 

From the FAA's "Pilot's Handbook of Aeronautical Knowledge" 2016 edition.

 

"An
 AOA indicator can have several benefits when installed in a General Aviation aircraft, not the least of which is increased situational awareness. Without an AOA indicator, the AOA is “invisible” to pilots. These devices measure several parameters simultaneously and determine the current AOA providing a visual image to the pilot of the current AOA along with representations of the proximity to the critical AOA. These devices can give a visual representation of the energy management state of the airplane. The energy state of an airplane is the balance between airspeed, altitude, drag, and thrust and represents how efficiently the airfoil is operating."

 

 

[bTW, for those who don't know it, this great book is available as a free download:

 

https://www.faa.gov/regulations_policies/handbooks_manuals/aviation/phak/media/pilot_handbook.pdf ]

 

And then there's this from Fred Scott in an article in Aviation Safety Magazine (June 2011):

 

"If you think a low-level stall/spin accident can’t happen to you, then ask why it is that neither training nor great experience are sufficient in every case ... pay particular attention to the table listing the types of pilot certificates involved in such accidents. Note the proportion of airline transport and commercial pilots, along with flight instructors ...

 

If you never plan to fly slow, close to the ground, then you may not wish to consider installing an AoA indicator. Of course, flying slowly and close to the ground is something we do every time we land or take off. The stall warning system will only tell us a stall is about to happen. By then, it might be too late."

 

Flying AOA - Aviation Safety Article.pdf

 

Flying AOA - Aviation Safety Article.pdf

 

Flying AOA - Aviation Safety Article.pdf

[vixen]

Of course all pilots know that in an aircraft accident there is almost never just one reason - usually the good old chain of events..

 

I wonder if the sun was a contributing factor here... he's flying into it and as the wing drops a significant reflective flash of the sun can be seen on the windscreen. As he started to tighten the turn was he momentarily blinded and lost his horizon reference? Plus (as Dutch alluded to) - the startle factor. (love that Dutch!).

 

I guess we'll never know but I suggest there are a lot more chain links to this tragedy than a simple "he stalled it turning finals".

 

 

[SDQDI]

Definitely more links.

 

If the near miss was as close as it appeared that would be enough to rattle anyone add anything else on top of that and it's not hard to get overloaded.

 

 

[JEM]

Definitely more links.If the near miss was as close as it appeared that would be enough to rattle anyone add anything else on top of that and it's not hard to get overloaded.

Just curious- Was the Cessna operating as part of the airshow or as a separate joy flight op. If separate would both aircraft have been using the airshow discrete frequency citybase 127.9 ? Are these frequencies monitored/recorded officially or by enthusiasts?

 

Maybe transmission recordings will help the investigation.

 

 

[facthunter]

Perth is not known as the windy city for no reason. I've probably flown in and out of it more than any other place, and you can get seriously difficult approach situations in some of the gusts. I've even had mini cyclone (dust devil without the dust) that caused the most scary situation I've ever been in . IF such conditions were there on the day it will be known to enough people for that to come out in the process of looking into this. The waves on the water look as if it's coming from over the trees, but not very strong velocity. Nothing in any Vid gave indications of encountering turbulence. The close call with the Cessna Caravan would have upset me. Nev

 

 

[Yenn]

In a stall spin event would an angle of attack meter be any help?

 

From what I know of them they are mostly part of the pitot system and as such would only give A of A at one point.

 

In a stall spin event one wing would be at a higher angle of attack than the other so would a meter necessarily show the highest A of A?

 

 

[Jaba-who]

Just curious- Was the Cessna operating as part of the airshow or as a separate joy flight op. If separate would both aircraft have been using the airshow discrete frequency citybase 127.9 ? Are these frequencies monitored/recorded officially or by enthusiasts?Maybe transmission recordings will help the investigation.

Read an AVweb article which says they were both listed as a joint display at the same time.

 

 

[Old Koreelah]

In a stall spin event would an angle of attack meter be any help...

The last thing a pilot needs in that situation is another gauge to look at. An audio warning might be more help.

 

 

[storchy neil]

that's two more gauges neil

 

 

[Oscar]

that's two more gauges neil

Not necessarily. We bought an inexpensive kit from the USA, and upon request, the kit maker not only added a take-off for the audio but a small piezo tweeter. As I understand it, the FAA requirements for stall warning is that it shall provide the pilot with a stall warning that does NOT require inside cockpit vision, so an audio horn or a stick shaker or a pre-stall buffet strip arrangement are all, I believe, satisfactory.

 

 

[Virago]

https://www.facebook.com/video.php?v=1380861511955930Another video of the accident, at the start it looks like it collided with the Cessna float plane which immediately turns back and lands.

 

condolences to the pilot and pax family and friends

While it may look like a collision, the Mallard is very much larger than the Cessna Caravan float plane therefore the Caravan (which appears to be larger) is much closer to the camera.

 

 

[Virago]

I've watched a bunch of different views of it too.There's really only one way you can interpret what happened here, and it's already been said. Very sad.

 

Tight manoeuvring at low level and slow speed - you've just gotta keep an eye on your energy level and be careful of g application. There are no second chances, unfortunately.

The ground temperature on the day was around 41 degrees, so there's a density altitude issue involved as well.

 

 

[facthunter]

The Mallard is not a particularly underpowered aeroplane. It was designed to operate with 2 pilots with around 10 passengers. The biggest problem with a flying boat is unsticking it from the water. Maybe that was why the touch and go as was reported was to be done. Nev

 

 

[Garfly]

Rather than continue the discussion about AoA indicators here, I've started a new thread in General Discussion.

 

I'd like to see if some of our recreational flyers have had experience with them and if they think they're of use.

 

 

[Chris SS]

The passenger posted a video on social media taken prior to the flight from various postions in the cabin.

 

The last 6-8 seconds of the video seem to put her in the front left seat?

 

 

[UltraFlash]

I was at the airshow and witnessed the accident first hand - the point of impact was 400m from where I was sitting. This was the worst 5 seconds I've ever experienced, as I saw the turn tighten with what appeared to be the application of left rudder, then the airspeed dropped off and then over it went. I knew from the start of that turn, as soon as the wing went over there was nothing that could be done.

 

In response to some of the questions, as I was sitting at a different angle to the 3 videos doing the rounds I can say the caravan and the Mallard weren't close on the first touch and go - would have been 100-200m apart. The steep climbing turn from the caravan did get my attention though. The incident happened on the third attempted touch and go, and the previous two were both too high, so it did seem that the third attempt was done lower and slower, presumably to come out on final with less height and energy to perform the touch and go in the limited space between the landing area and the narrows bridge.

 

Also there were crowd lines on both sides of the shore as well as hundreds of boats to the east, restricting the space to make the turn to base and final.

 

The incident happened when the aircraft was flying East and was turning through north when it banked over, so the sun wouldn't have been an issue.

 

The other part I hadn't had any explanation of was the fact that both aircraft appeared to finish their sequence and left the display area via the standard departure over the narrows, then south towards Canning bridge. Then, I saw the mallard make a left turn, flying over South Perth and onto this turn where the incident occurred. Until the start of the turn, I was wondering why he had flown back.