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DA42 LN-PFM down in Norway

In the meantime another fatal DA42 accident in training environment…

LDZA LDVA, Croatia

You don’t get many points for a spin in a competition AFAIK. I also think one single turn gives more points than 2 for instance. Anyway, that’s what I have heard. I don’t fly competition aerobatics, and have no immediate plans

As Emir posted above, the DA-42 obviously has a procedure to get out of a spin which looks very standard, and certainly can be practiced in any aerobatic plane. Would that have helped? no one knows for sure, but judging by the outcome, it’s not really possible to do anything that should make it worse.

And then there are these subtle things. If you haven’t spun for years and by accident enter a spin, I am not sure if you are even able to figure out which way you spin. If you eventually do, and you do what the POH say, then the plane will not react immediately. It takes some time before the spin stops. More than enough to make you think that nothing is happening and you try something else. Why didn’t they get out of the incipient spin is perhaps a better question, because that is a much more straight forward thing to do. Why did they make the situation worse instead of making it better? Did they start with a flick roll and tried to “recover” from it?

Beats me. When flying aerobatics we always were a chute, for whatever that is worth. A better option would certainly be BRS.

The elephant is the circulation
ENVA ENOP ENMO, Norway

The tendency to flat spin is typical of an MEP, while RoD is less than a normal spin, it still is around 5,000 fpm.

Also please note upright spins are typical in Sport and Intermediate competition sequences, usually of the 1 1/2 turn variety, but occasionally the more subtle 1 1/4 turn. These are Aresti manoeuvres and flat spins are not, but flat spins might be displayed in the unlimited category. Advanced you have inverted spins.

Oxford (EGTK), United Kingdom

LeSving wrote:

One plane entered a normal spin that later developed into a flat spin. The other did not.

Both planes entered a spin. One plane continued spinning until it hit the ground. The other managed to transition into a flat spin, and later hit the ground.

The difference could be that the one which entered flat spin tried to use differential power to exit the spin.

LDZA LDVA, Croatia

They spun for the 30 seconds before ending up in the woods, initially 10 000 ft/min and then 3700 ft/min descent.

This is also interesting. The other report mentioned steady 8000 ft/min descent. Flat spin is characterized by a relatively slow rate of descent. One plane entered a normal spin that later developed into a flat spin. The other did not.

Both planes entered a spin. One plane continued spinning until it hit the ground. The other managed to transition into a flat spin, and later hit the ground.

Both FIs failed at preventing the initial spin to happen in the first place. They failed at recovering from the incipient spin. They failed at recovering the developed spin. One made it worse by transition to a flat spin, which miraculously also saved their lives btw.

I mean, when it quacks like a duck…

The elephant is the circulation
ENVA ENOP ENMO, Norway

Airborne_Again wrote:

The aircraft inadvertently entered a flat spin

Which is the key point. How do you do that? and why ? Perhaps the same problem as “inadvertently” entering IMC when VFR ? A plane does not all by itself, all of the sudden, enter a flat spin.

The elephant is the circulation
ENVA ENOP ENMO, Norway

This post from an old thread is highly relevant to this discussion: (I don’t link to the actual thread as it derailed almost immediately to questions about flight training safety in general.)

Fly310 wrote:

I came to think of this after reading the spin recovery thread.
Recently the final report was released of an accident with a DA42 that belonged to a flight school in Sweden. The report is in english and here is a brief summary(spoiler!) before you read the full report:

Date: 2016-01-22, 7 pm(so it was dark)
Aircraft: DA42 Twinstar
Occupants: One instructor and two students
Weather: Low overcast at about 400 ft up to 2000 ft

They were at 4500 ft and the instructor was demonstrating deep stall. Initially 25-30 degrees pitch up with a 30 degree bank to the left. Before approaching the stall full power was applied and the stick was taken further back.The aircraft inadvertently entered a flat spin which the instructor was not able to recover from despite using differential power. They spun for the 30 seconds before ending up in the woods, initially 10 000 ft/min and then 3700 ft/min descent. And this is the amazing part, they all survived with non lethal injuries!

The aircraft was pierced by a tree and spun around it whilst the wings kept hitting nearby trees in the rotation which slowed everything down. The student in the back was tossed out of the aircraft when the tree pierced it and was the one with least amount of injuries. An amazing outcome of what usually is a lethal accident for all occupants.

ESKC (Uppsala/Sundbro), Sweden

RobertL18C wrote:

Practising precision spinning in an aerobatic type might build resilience, but may not prepare an FI for understanding the difference between incipient spin recovery, and spin recovery from a stable fully developed spin.

It certainly will. Spin is not a real aerobatic maneuver according to most aerobatic pilots (perhaps an inverse flat spin is, I don’t know). The only “difficult” part about a spin is to count the number of turns and exit at the right point, and this is not seen as “difficult enough” for the higher classes. For me as an amateur it is though

Incipient spin and spin are both good warm up practices. It get’s you in the mood and brushes off some rust. To control the aircraft at the very edge of incipient spin is a basic skill you learn before anything else actually. Idle power, stick fully aft, then prevent the plane from flipping by using rudder only. Very easy in a C-172 because you don’t have to do anything. Much more difficult in an aerobatic plane because it is designed to flip over and spin in that condition, and will do so in an instant. It’s very much like balancing a broom or similar. Recovering from the first flip is usually very easy though, and when rusty/new you will do that a lot You basically end up upside down, pointing down at low speed, and all you have to do is to let go of the back pressure.

Another thing is that maneuvers often go bad/wrong, and you end up in an awkward position. Out of speed, upside down, pointing half upward for instance. Then what do you do? The only thing to do is to release all pressure on the stick and rudder, get the lowest wing pointing down, and let the aircraft recover itself. An aircraft will not stall at zero G.

RobertL18C wrote:

The regulators and accident investigators should spend some time digging further on the root causes of this unfortunate accident.

It probably will be discussed at several places.

The elephant is the circulation
ENVA ENOP ENMO, Norway

POH:

Steps 1 to 4 must be carried out immediately and simultaneously.
1. POWER levers IDLE
2. Rudder full deflection against direction of spin
3. Elevator (control stick) fully forward
4. Ailerons neutral
5. FLAPS UP

When rotation has stopped:

6. Rudder neutral
7. Elevator (control stick) pull carefully
8. Return the airplane from a descending into a normal flight attitude. Do not exceed the ‘never exceed speed’, Vne = 194 KIAS.

END OF CHECKLIST

LDZA LDVA, Croatia

@Emir thank you.

1. I learned that the VEBS is related to accelerated stalls and not intended to prevent a deep stall (ie unrecoverable due to tail-plane blanking), although arguably this maybe semantics as you may need to carry out an accelerated stall to enter deep stall risk territory?
2. I was surprised at the ‘incipient spin’ recovery technique in the SOPs and wonder whether this is quoted from the POH? ’If a wing drops, which often happens due to poor pilot technique where the airplane is out of balance at the stall, or aileron input is being used, we must somewhat alter our stall recovery. Once the wing stalls, aileron input will not stop the roll, it will worsen the situation, in these cases the rudder should be used to prevent the nose of the airplane yawing. If the wing drop is not promptly recovered, a spin may develop. Excessive rudder should not be applied (to level the wings through the secondary effect of rudder) as this may cause a stall and flick manoeuvre in the opposite direction to the initial roll (wing drop).
3. I also note the SOPs do not emphasise eliminating all symptoms of the stall in the stall recovery first action, and do not discuss the concept of a safe speed before applying, smoothly power for the recovery.

I am sure the incipient spin technique, which I hope is the ATO SOP and not Diamond POH, is written with the best of intentions, but it is a ‘potage’ of concepts not explained correctly and arguably wrong: No memory items; not focusing on the need to centralise all controls promptly at the first indication of un-commanded yaw (discusses roll, when the un-commanded yaw is causing the wing drop and incipient spin); fails to call for ensuring power has been reduced to idle (we have not one but two gyroscopes and torque/propeller effect conditions, especially if applying troglodite regulator imposed incorrect CPL stall recovery technique of applying full power before eliminating all stall symptoms and below safety speed); when stabilised, roll level and recover smoothly from ensuing dive; apply smooth power and establish gentle climb.

Practising precision spinning in an aerobatic type might build resilience, but may not prepare an FI for understanding the difference between incipient spin recovery, and spin recovery from a stable fully developed spin.

The regulators and accident investigators should spend some time digging further on the root causes of this unfortunate accident.

Oxford (EGTK), United Kingdom
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