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The Downwind Turn - What Isn't Covered in the PPL Syllabus

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The Downwind Turn - What Isn't Covered in the PPL Syllabus

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Old 2nd Feb 2017, 20:17
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The Downwind Turn - What Isn't Covered in the PPL Syllabus

I am continually amazed to discover what I don't know. Quite often there is the joy of discovery of something new. Other times there is perhaps frustration at discovering something that I should have known. The tragic Mallard crash demonstrated to me that I have been flying on thin ice, so to speak, because I never appreciated up to now the dangers of uncoordinated flight and optical illusions flying close to ground.

Of course I know that stalling speed increases with bank angle and associated load factor. I know it is a trap to get caught with a tail wind on base, however no one has ever put together the scenario for a stall/spin accident for me, not in the classroom and certainly not in the air. I suspect other PPL holders may have had the same experience - a bit of theory and the demonstration of a power off spin at 4000 ft together with the admonition "don't do this".

Wouldn't it be better if we at least demonstrated a stall leading to an incipient spin of the base to final turn? Shouldn't we all know the warning signs and traps that are waiting for us? Shouldn't we be able to identify the mistake and recover instantaneously? I think we should.

Instead all I got was seventy knots on base, make a nice coordinated turn to final. Nobody ever explained, let alone demonstrated " this is what will happen to you if you do X instead of Y".

Where is CASA on this? Where is there some thought leadership on training?
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Old 2nd Feb 2017, 21:00
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Page 190 of the 1994 book Stick and Rudder: An Explanation of the Art of Flying :
"Almost all fatal flying accidents are caused by loss of control during a turn!"

70 years later: CASA, ATSB, NTSB say similar to the FAA:
"Loss of Control-Inflight remains the top fatal accident category in GA ... and occurs most often .. while turning.”

A lot going on in the USA however in Australia just diddly squat when CASA asked about future safety challenges for FlightPlan2030 my answer was the same as it has been for the previous 70 years.

I recall a recent ATSB report of a stall/spin accident following an engine failure guessed to be card icing. It shouldn't have been fatal. CASA simply cautioned pilots about the dangers of carb icing with no mention of avoiding a stall/spin.

Part 61 introduces greater scope of advanced stalling exercises in ab initio training - one CFI told me that his instructors probably wouldn't do it as they'd be scared. With CASA's new definition of aerobatics (why depart from ICAO, EASA and FAA?) anything beyond a straight stall really requires an aerobatic/spin training endorsed instructor now.

Anyway sunfish - you're free to seek further training - that thought is still free in this country.
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Old 2nd Feb 2017, 21:42
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There is an thread running here in the Private Flying Forum.
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Old 2nd Feb 2017, 22:07
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Wouldn't it be better if we at least demonstrated a stall leading to an incipient spin of the base to final turn? Shouldn't we all know the warning signs and traps that are waiting for us? Shouldn't we be able to identify the mistake and recover instantaneously? I think we should.


When I used to do the advanced stalling lesson I tried to simulate that exact scenario (albeit at 3,500' min AGL) ie set the A/C up in the approach configuration eg 1500 RPM and 20deg flap, put it into a descending turn eg base to final, overbank the turn and keep pulling back on the control column until...Woohoo..! Certainly got the students attention, especially when you got a wing drop in the opposite direction to the turn. Then followed up with a climbing turn eg upwind to xwind, again pulling back until the inevitable happens. After the student has done these a couple of times and shown they can recover safely, followed by a reminder about how difficult it would be to recover in time if this happens at low level eg in the circuit, they would hopefully have a healthy respect for the potential danger and avoid the situation. Obviously the co-ordinating of the turns including climbing & descending turns had already (hopefully) been covered.


Is this advanced stalling not taught anymore..? It used to be part of the syllabus I thought.
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Old 2nd Feb 2017, 22:08
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In defence of the instructing of the instructing fraternity, I don't believe I was left suffering any illusions about the dragons that lurked behind uncoordinated turns close to the ground. A floor of 3,000' agl + 500' feet for a a simulated base to final turn at low speed, a deliberate stall whilst skidding and then once it was all squared away, a significant tap on the altimeter, now reading somewhat less than 3,000' - I got the point. Of course this was in a time and place where we were taught to spin and recover - funnily enough despite the use of what are now considered unsuitable aircraft, I am not aware of a single accident arising from the practice, but that's an argument for another day.
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Old 2nd Feb 2017, 22:25
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All my students were trained about this.
In addition to initial training the new owner/operator of new aircraft types should do their own slow speed testing with suitable altitude, I do this with any new types I fly.
Of course many are now too scared of stalling (or spinning!) to have any idea how their aircraft fly!
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Old 2nd Feb 2017, 23:48
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One thing I don't recall ever being taught is the powerful visual illusion that comes from making turns at low level when a high wind is blowing, and the effect that illusion can have on control inputs.
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Old 3rd Feb 2017, 00:04
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Yes because DOT/CAA/CASA have always believed it to be highly dangerous to fly at low level and thus forbid people from learning about it under instruction at ab initio stage.

It's also illegal to fly in cloud on instruments, but we teach that to VFR students as a get out of trouble.

Then it is legal to fly below 500' due stress of weather, where illusions of the type that "may" have caused this crash are likely. But CASA won't let you train for it?
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Old 3rd Feb 2017, 00:48
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sunfish , the downwind turn is not on the PPL syllabus because there is no such thing .
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Old 3rd Feb 2017, 01:03
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Interesting stuff after 2:10

Not downwind turn, but base turn to final relevant.
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Old 3rd Feb 2017, 01:23
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the downwind turn is not on the PPL syllabus because there is no such thing
???? I'm afraid you'll need to be a little more fulsome explaining that.

rjtjrt, a good reminder. No idea what is on the syllabus these days, and don't know what was on the syllabus when I trained in the early 60s, but we did stalls power on and off straight ahead, power on in a climbing turn, power off in a descending turn, though don't recall the recovery being as dramatic as in the video. Memory cell fade perhaps, because I sure know the danger - stall, spin as video instructor comments upon.
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Old 3rd Feb 2017, 01:38
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Oh good, another downwind turn thread.....
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Old 3rd Feb 2017, 01:47
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Please read this first before posting...

Dragons of the downwind turn - Australian Flying

Or this...

https://foxbatpilot.com/2014/06/17/t...own-wind-turn/

Or this...

http://www.flyingmag.com/pilots-plac...d-turns-really

Or this...

http://www.recreationalflying.com/th...downwind.3962/

This one has pictures...

http://www.gbfs.co.za/images/Dragons.pdf
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Old 3rd Feb 2017, 01:51
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Originally Posted by IFEZ
Is this advanced stalling not taught anymore..? It used to be part of the syllabus I thought.
Not only was I taught this, but had to demonstrate stalling in a descending turn in approach config as part of my flight test - a while ago, but not all that long ago.
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Old 3rd Feb 2017, 02:05
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Wouldn't it be better if we at least demonstrated a stall leading to an incipient spin of the base to final turn? Shouldn't we all know the warning signs and traps that are waiting for us? Shouldn't we be able to identify the mistake and recover instantaneously? I think we should.
No.


What is the problem you are trying to solve? Are there dozens of these events every year?
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Old 3rd Feb 2017, 03:19
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it was covered in the PPL syllabus in the UK in the lesson "operations at minimum level" which included turns around a point. There is no such lesson in the Aus syllabus and the closest you get is the precautionary search and landing exercise.

What students need is to understand how a series of bad decisions will lead to a scenario where a stall can happen and how to stop the "swiss cheese" holes lining up. It's not going to happen at 3500 feet with plenty of warning and then a sudden yank and boot on the controls out of nowhere and then a shove forward to solve it. Completely unrealistic.

It's going to happen when everything is turning to sh#t VFR into IMC, turnback after EFATO, optical illusions at low level in strong winds, badly handled go-around, idiots showing off with low passes and pull ups etc but most of all disorientation, not believing what is happening, brain playing tricks on you. Learn to recognise and rectify a deteriorating situation before it is too late. Human factors. Then learn what it looks sounds and feels like and how the aeroplane if trimmed right will recover pretty well on its own.

Lots of youtube vids of analysis of loss of control accidents in light aircraft which are much more informative than some of the "particle a" type pre-flight briefings.
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Old 3rd Feb 2017, 08:54
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Shouldn't we be thinking, well before reaching base leg, about what wind to expect there?
If tailwind, a slightly wider base turn is best, to allow for the higher groundspeed. Also there is a higher possibility of overshooting final, so I'd better turn final a bit earlier than usual. If that all fails, am I going to incur the wrath of ATC for infringing the counter-rotating circuit? Will I be able to resist the urge to markedly increase the bank angle to solve all my problems?
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Old 3rd Feb 2017, 10:40
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What is the problem you are trying to solve? Are there dozens of these events every year?
It's one of the biggest killers in US GA, accounting for 25% of fatal accidents.

http://eaavideo.org/video.aspx?v=1997693826001

https://www.aopa.org/asf/publication...m?article=4023

Ease into the Base-to-Final Turn | Flying Magazine

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Old 3rd Feb 2017, 11:00
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It's one of the biggest killers in US GA, accounting for 25% of fatal accidents.
None of your links verify that statement. do you have a link that shows the numbers. I find it hard to believe that this is a problem that requires a solution. The syllabus seems robust enough to me.
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Old 3rd Feb 2017, 11:28
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None of your links verify that statement. do you have a link that shows the numbers.
Icarus, I cant give you a link, but some years ago I looked at all the fatal accidents that were available on the ATSB web site. About 115 between 1990 and 2004 (call it 15 years). The accident reports wont call it a spin accident but the description always ends up like "low speed loss of control followed by ground impact in steep nose down attitude".

Of those 115 fatal accidents, 31 were stall/spins which lines up with Megans figure of 25% for the US. It's about 2* per year.

Further, of those 31;
2 were badly loaded aircraft
2 were visibility related (one night, one cloud)
3 were during aeros
9 followed after engine problems (mechanical issues or fuel, including one purposeful shut down)
15 were perfectly good aeroplanes where things just got out of hand.


*2 per year does not include gliders, which are less than GA, but one happens every few years. I have no data at all for RAAus (which would have to be similar to GA)

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