Voepass Flight 2283, a large passenger plane, crashes in Vinhedo, Brazil

No. Not trained for that AT ALL.
 
TrueCourse said:
I don’t think anyone can say at this point that there was no effort get out of it. All we see is a video of it in a flat spin. What percentage of heavy turboprops are certified to recover from a flat spin? Probably none.
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Thanks.

What you're telling me is that I should not fly in such planes since as we saw, they will spin and they can't be recovered.

I would think though that if they pull the power, they're flying a glider and if CG is within limits, the nose down stick should respond.
 
Himayeti said:
Thanks.

What you're telling me is that I should not fly in such planes since as we saw, they will spin and they can't be recovered.

I would think though that if they pull the power, they're flying a glider and if CG is within limits, the nose down stick should respond.
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The spin dynamics of a multiengine transport airplane are very different from those of a glider.
 
Juan Browne (Blancolirio, linked above) says a (flat?) spin in this airframe may be un-recoverable. He cites the weight of the engines and insufficient rudder authority.

HHH

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Himayeti said:
AI agrees:


Which tells me I should not fly in these planes if safety is a concern?
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The question begs. It seems to me that if a big aircraft, be it an ATR 72, a 737 Max or an Airbus can't get out of a spin yet it can enter a deadly one, as we've seen in the recent past, they would all have serious design faults regarding the CG envelope.

There have been a few recent glider accidents where they spun, they were irrecoverable, and all were due to an improper CG.
 
Himayeti said:
Which tells me I should not fly in these planes if safety is a concern?
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I've no experience flying anything that big, but I suspect any transport-category aircraft can get into a non-recoverable situation of some sort or other.

Whatever the aircraft, you are trusting the pilots to keep the aircraft within the envelope. It almost always works.
 
Warmi said:
I believe a plane like ATR 72 may actually not be recoverable in certain spin scenarios ( depending on COG configuration ) ….
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Of course it isn't. It was a flat spin. Not recoverable unless you can shift the CG.

Hunter Handsfield said:
Juan Browne (Blancolirio, linked above) says a (flat?) spin in this airframe may be un-recoverable. He cites the weight of the engines and insufficient rudder authority.
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So we need JB's opinion, really? The rudder authority in a flat spin is zero in any aircraft, not just an ATR.
 
dmspilot said:
So we need JB's opinion, really? The rudder authority in a flat spin is zero in any aircraft, not just an ATR.
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Nobody "needed" anything, including condescending comments. I was only replying to a couple of posts before my own.

HHH
Screen Shot Airports Landed.png
 
Any anti-ice solutions for turboprops like ATR such as hot leading edges? De-ice boots allowing ice formation is only option?
 
Himayeti said:
Air France accident over the ocean in Brazil also hit the water with a flat spin.
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AF 447 was not a flat spin, not even a deep stall. They held the 330 in a stall until it was too late to recover.
 
Rein Hart said:
Any anti-ice solutions for turboprops like ATR such as hot leading edges? De-ice boots allowing ice formation is only option?
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I seem to recall them considering doing hot leading edges on the Dash 8 Q400, it has enough excess power to provide acceptable performance even when supplying the anti-ice system. Even you don't get the leading edges hot enough it's even worse than boots.
Most turboprop regional aircraft are not exactly over powered, so boots are the easy/cheap solution.
 
dmspilot said:
So we need JB's opinion, really? The rudder authority in a flat spin is zero in any aircraft, not just an ATR.
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It's not zero in any aircraft and in the case of the ATR it should be more effective in an upright flat spin than many other aircraft, as practically none of the rudder is blanked by the elevator.
 
Spinka said:
It's not zero in any aircraft and in the case of the ATR it should be more effective in an upright flat spin than many other aircraft, as practically none of the rudder is blanked by the elevator.
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Okay, then read it is "negligible." Why do you believe elevator blanketing is the important factor? The Piper Tomahawk should be great at flat spins then.
 
Himayeti said:
Agreed. Let me know how you obtain this kind of information before you get on a plane...
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The one crew I can think of that’s spun a transport category airplane is dead, so if you pick a crew that’s not dead, you should be safe from spins in transport category aircraft.
 
dmspilot said:
Okay, then read it is "negligible." Why do you believe elevator blanketing is the important factor? The Piper Tomahawk should be great at flat spins then.
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I didn't say it's "the important" factor. You made a blanket statement regarding rudder authority.
The anatomy of spins in different aircraft are highly complex and there are many factors involved.
In something like the ATR-72 with T-tail and those wing mounted big props even more so.
 
AV8R_87 said:
So... one more thing to consider.

Brazilian ATC is run by the military, and from past incidents/accidents in that area it looks like you can get into a lot of trouble if you deviate from their instructions.
That might explain the crew's actions.

canso.org

DECEA - CANSO

DECEA - CANSO Member
canso.org canso.org
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Getting into trouble would have been the better alternative in this case. Hell even if they started shooting at you, that would still have been the better option.
 
AV8R_87 said:
Easy after the fact.
When an ATC deviation gets you into a very likely loss of job situation, you might tend to minimize the danger that your current icing situation poses.
I'm not saying it's the correct decision, but they did operate in an environment that is not your typical FAA-land.
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Local culture is definitely worth taking into consideration; there has been more than one first officer in SE Asia that watched the captain fly the plane into the ground without saying a word because you just don’t question authority over there. But I would guess this was just icing on a level they had never experienced and didn’t respect. There’s a picture on PPRUNE of an Airbus that landed at their destination that same day with the windshield completely iced over.
 
Himayeti said:
The question begs. It seems to me that if a big aircraft, be it an ATR 72, a 737 Max or an Airbus can't get out of a spin yet it can enter a deadly one, as we've seen in the recent past, they would all have serious design faults regarding the CG envelope.

There have been a few recent glider accidents where they spun, they were irrecoverable, and all were due to an improper CG.
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Transport category have completely different handling requirements than your glider. A simple stall recovery can take tens of thousands of feet alone, which is why the training emphasis is on avoidance. Spin testing is not required nor completed on these aircraft.
 
Warmi said:
Well, death or “a lot of trouble” …. decisions, decisions….
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People make lots of bad decisions between death or trouble. We all know what it's like to get in trouble, and that we don't like it, so we avoid it like crazy. We don't know what it's like to get dead, so we don't avoid it the same way. Sounds crazy, but it happens all the time.
Spinka said:
AF 447 was not a flat spin, not even a deep stall. They held the 330 in a stall until it was too late to recover.
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It wasn't a spin, but it was absolutely a very deep stall - Up to 40 degrees AoA IIRC. It was in a deep enough stall that the computer thought there was no way it was stalled and shut off the stall warnings. When they began to actually think it was a stall and attempt a recovery, it got to where it was just a few degrees above critical AoA and the computer decided maybe it really was stalling and set off all the warnings, so the crew un-did what they'd just done and got it back into a deep stall.
 
flyingcheesehead said:
It wasn't a spin, but it was absolutely a very deep stall - Up to 40 degrees AoA IIRC...
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Deep stall in an aerodynamic sense is when the AOA is high enough that there is insufficient nose-down control power to recover. It's not simply "high AOA." AF447 was not in a deep stall, it was responding to nose-up pitch commands from the cockpit.

Nauga,
and his pinch point
 
nauga said:
Deep stall in an aerodynamic sense is when the AOA is high enough that there is insufficient nose-down control power to recover. It's not simply "high AOA." AF447 was not in a deep stall, it was responding to nose-up pitch commands from the cockpit.
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Interesting. Never seen that definition before. Thanks.
 
Not related to this, but interesting.
Seems they barely escaped, notwithstanding what seems to have been ridiculous ADM by trying to "climb out" of severe icing conditions despite barely having enough lift to maintain level flight :oops:

www.flightglobal.com

Flawed bid to outclimb icing led to serious ATR upset

UK investigators have determined that an Aurigny Air Services ATR 72-500 suffered a serious in-flight upset after its crew vainly attempted to climb out of a region of icing instead of following the correct checklist procedures.
www.flightglobal.com www.flightglobal.com
 
Himayeti said:
The video is painful to watch because the spin remains flat throughout, and no apparent effort is made to get out of it (stick in center, push forward, and opposite rudder).
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In a flat spin, with very little control authority due to lack of forward speed and blanketing of tail surfaces, combined with the inertia of two wing-mounted engines far away from the center of rotation, there is likely no accessible recovery mode. Incipient stall recovery needs to be initiated before things develop into a spin. Some GA aircraft (including my AA-5) will not recover from a well-developed flat spin.

I suspect there must have been some exacerbating factors that precipitated the stall/spin entry. The weather reports at the time are strongly suggestive of icing potential, and there were some airspeed and altitude excursions immediately prior to the precipitous descent. Hopefully, the investigators can sort things out.
 
chemgeek said:
In a flat spin, with very little control authority due to lack of forward speed and blanketing of tail surfaces, combined with the inertia of two wing-mounted engines far away from the center of rotation, there is likely no accessible recovery mode. Incipient stall recovery needs to be initiated before things develop into a spin. Some GA aircraft (including my AA-5) will not recover from a well-developed flat spin.
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What about using differential thrust?
 
flyingcheesehead said:
What about using differential thrust?
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My understanding from my recent training was that most twins cannot recover from a spin, no matter what you try. Still, recovery procedures did not mention asymmetric thrust, just the regular "power idle/ailerons neutral/nose down/opposite rudder" technique.
 
I wonder if it's a case of not noticing that the autopilot has been adjusting trim to account for a deteriorating condition, e.g. icing, until it hits the trim limit and says "here, you fly now" and hands over a very difficult situation.
 
MFE said:
I wonder if it's a case of not noticing that the autopilot has been adjusting trim to account for a deteriorating condition, e.g. icing, until it hits the trim limit and says "here, you fly now" and hands over a very difficult situation.
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Then mash the power levers forward without trimming, and follow up with a trim stall?
 
MFE said:
I wonder if it's a case of not noticing that the autopilot has been adjusting trim to account for a deteriorating condition, e.g. icing, until it hits the trim limit and says "here, you fly now" and hands over a very difficult situation.
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That's what I'm thinking
 
MFE said:
I wonder if it's a case of not noticing that the autopilot has been adjusting trim to account for a deteriorating condition, e.g. icing, until it hits the trim limit and says "here, you fly now" and hands over a very difficult situation.
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Wasn't that what happened at Roselawn, which was another ATR IIRC?
 
flyingcheesehead said:
Wasn't that what happened at Roselawn, which was another ATR IIRC?
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No.

Probable Cause the loss of control, attributed to a sudden and unexpected
aileron hinge moment reversal that occurred after a ridge of ice accreted beyond
the deice boots because:

1) ATR failed to completely disclose to operators, and incorporate in the ATR 72
airplane flight manual, flightcrew operating manual and flightcrew training
programs, adequate information concerning previously known effects of
freezing precipitation on the stability and control characteristics, autopilot and
related operational procedures when the ATR 72 was operated in such
conditions;

2) the French Directorate General for Civil Aviation's (DGAC's)inadequate
oversight of the ATR 42 and 72, and its failure to take the necessary
corrective action to ensure continued airworthiness in icing conditions; and

3) developed from previous ATR incidents and accidents in icing conditions, as
specified under the Bilateral Airworthiness Agreement and Annex 8 of the
International Civil Aviation Organization. Contributing to the accident were: 1)
the Federal Aviation Administration's (FAA's) failure to ensure that aircraft
icing certification requirements, operational requirements for flight into icing
conditions, and FAA published aircraft icing information adequately accounted
for the hazards that can result from flight in freezing rain and other icing
conditions not specified in 14 Code of Federal Regulations (CFR) Part 25,
Appendix C; and 2) the FAA's inadequate oversight of the ATR 42 and 72 to
ensure continued airworthiness in icing conditions. (NTSB Report AAR-96/01)
 
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