Voepass Flight 2283 Crash in Brazil - No survivors

[Anti Federalist]

https://x.com/i/status/1821970641140232640

 

[Matt Collins]

Some were thinking icing

 

[Dr.3D]

Wow, no forward motion and a complete stall.

 

[sparebulb]

I spent several years flying the ATR.

It is a very capable aircraft, even in icing.

It has a very strange wing that must never be flown below the exactly computed minimum speeds relative to weight, icing conditions, bank angle and flap configuration.

Not that any other aircraft should be operated below their critical speeds either, but this one is a no-shat deal.

And it is a delight to fly, especially the 72.

 

[luctor-et-emergo]

Looks almost like a flat spin, but it's definitely a stalled condition and for sure unrecoverable from a while before this video started.

 

[Matt Collins]

https://www.youtube.com/watch?v=ozinSmylTmQ

 

[Matt Collins]

I spent several years flying the ATR.

It is a very capable aircraft, even in icing.

It has a very strange wing that must never be flown below the exactly computed minimum speeds relative to weight, icing conditions, bank angle and flap configuration.

Not that any other aircraft should be operated below their critical speeds either, but this one is a no-shat deal.

And it is a delight to fly, especially the 72.

yikes... I was hanging out in a Vegas FBO today and we were kicking it around. I used to fly the Brasilia, a 30 seat turbo-prop which IMO is a much less complicated aircraft systems-wise, and also a lot more straight forward aerodynamically.

 

[Anti Globalist]

RIP to all the people aboard that plane.

 

[Anti Federalist]

[MENTION=991]Matt Collins[/MENTION]
[MENTION=5574]sparebulb[/MENTION]

Are either one of you men still flying commercially?

I'm just a rinky dink PP, but as soon as I heard "Flight into known icing conditions", well, it was lights out for everybody.

What a shame.

Comments on this video please.

 

[sparebulb]

Just watched that video.

It is valid from a pedestrian or general aviation perspective, and all signs point to this being an icing related issue.

The icing issues with the ATR are complicated and very aircraft-specific.

I will try to condense this as much as I can to illustrate the ATR's relationship to icing.

My knowledge is 30+ years old on this aircraft, so please forgive me of any errors.

The ATR has a strange airfoil that was known to have icing issues in its development. Don't be alarmed, most aircraft do as well. In its inception, the wing was fitted with anti-ice pneumatic boots on the wings instead of de-ice boots.

De-ice boots are the standard for nearly 90 years now. They are ribs of synthetic rubber on the leading edges of the wings. When flying in icing conditions, the theory and practice is that you allow a significant buildup of ice on the leading edge until you are confident that the inflation of the de-ice boots can break apart the buildup and the airflow will blow it off the edge. A premature activation of the boots may result in the buildup not breaking off or not breaking off cleanly. Waiting to activate the boots result in serious loss of lift/airspeed and brings you close to unknown wing behavior because you have created a new airfoil, in effect, that likely has a far higher and unpredictable stall speed. Experience hones nuanced strategies in this and most people elect to avoid prolonged exposure to significant icing, although some encounters are unavoidable.

The ATR anti-ice boots comprise of vertical ribs of synthetic rubber which are activated just as soon as ice accretion is sensed by an ice detector. These boots automatically inflate and deflate constantly. They are not meant to break off a large buildup of ice, they are meant to keep the buildup of ice small, but relatively the same shape as the leading edge of the wing. You cannot see the wings from the cockpit and there is a phallic-looking metal airfoil just outside of the captain's side window which mimics the shape of the wing leading edge to give you a visual confirmation of icing. The windshield wipers are good as well.

There are three icing levels. Normal operations are level one, the usual stuff pitot/static port heat, windshield heat, etc. Level one is always on, you can't turn it off unless you pull breakers.

Level 2 is when you are in visible moisture below a certain temperature. It is selectable. I can't remember what all but engine inlet heat and such come to mind.

Level 3 is activated when the ice detector goes off. It is selectable. The anti-ice boots are activated. Just like a Ronco product: Set it and forget it.

Well, of course, it is not that easy. Every flight, for all phases of flight, icing speeds are calculated for takeoff and landing relative to weight and flap setting. Once Level 2 or 3 icing is on, all minimum icing speeds must be observed. They are much higher than if the wing was free of ice. This wing has a tendency to slow down when wet, and much more so when there is ice accretion. Fortunately, at 17,000ft and lower, you have plenty of power to play with, but all bets are off in freezing rain. Once the airspeed bleeds off to the minimum icing speed that is noted on the airspeed indicator, you have to descend or add flaps. Once flaps are added, you have to observe each incremental appropriate minimum speed for each flap setting.

The American Eagle crash in the early 90's is similar to this but with a twist. The were instructed to enter a hold while going into Chicago on a real shi+ty day. Freezing rain at 10,000ft and expected to observe the then-required speed limit of 175kts in holding. They were heavy and I remember thinking that the clean min icing speed when heavy was right around 170 kts or so. The crew did notice that they were getting slow and they did add flaps, but they probably underestimated how much power they would have to punch in to keep the speed while pitched up, icing, and in the turn. The airplane stalled and flatspinned into Roselawn.

Every pundit who possessed a private pilot license forever arm-chaired quarterbacked what dumbasses the pilots were for flying around with flaps in ice. No one wants to hear the whole story of the ATR wing in ice because just see how long it takes to briefly explain it.

The ATR's were all grounded everywhere but the tropics for months. Exhaustive testing reaffirmed it to be suitable for icing conditions if the minimum speeds were observed. But because they had to do something, every ATR everywhere had several mods performed. One of them were anti-ice boots which extended further back on the wings to prevent a peculiar ice buildup on the top of the wing which was believed to cause a possible aileron hard-over. I remember seeing that same ice buildup on the a/c that had just come in prior to deicing. Everyone probably had a brush with death and never knew it, or everyone where I worked observed the proper speeds and procedures.

Would I ride on an ATR? No.

Is it because of its safety record and icing? No.

It is because of the numbnuts who they have been hiring for years now.

I only fly commercially if my life somehow otherwise depends on it.

 

[sparebulb]

The video had some interesting stuff.

The one young doctorette was quite attractive.

The copilot was 61.

I wonder whether this was a case of two captains flying together. Believe it or not, there is a high incidence of accidents when two captains fly together.

Or whether the old guy was substandard.

I'll be 60 soon, so I can say it.

 

[Anti Federalist]

Thanks for the detailed info.

One other question: if you put an ATR in a spin, can it be recovered from?

 

[sparebulb]

Thanks for the detailed info.

One other question: if you put an ATR in a spin, can it be recovered from?

Doubtful, like most twins and large aircraft.

Cpt. Hoot Gibson famously stalled a TWA 727 in an alleged dumbass move. Legend has it that it was a spin, but it is kind of hard to tell in a high altitude deep stall when there is a bit of rotation involved.

In the late 70's or so, the FAA dabbled in spin recovery with, I believe, a Beech Duchess. It was recoverable early in a spin, but they didn't pursue making it a certification standard.

 

[Anti Federalist]

Doubtful, like most twins and large aircraft.

Cpt. Hoot Gibson famously stalled a TWA 727 in an alleged dumbass move. Legend has it that it was a spin, but it is kind of hard to tell in a high altitude deep stall when there is a bit of rotation involved.

In the late 70's or so, the FAA dabbled in spin recovery with, I believe, a Beech Duchess. It was recoverable early in a spin, but they didn't pursue making it a certification standard.

So the video summation seems to be correct.

Flight into heavy icing, lift gets reduced, power is increased along with angle of attack in an attempt to maintain altitude, pre stall buffeting occurs, wing stall occurs, with uneven lift a roll then yaw begins, spin is introduced and cannot be recovered from.

Let's say you found yourself in the exact same situation just prior to the wing stall or just when you observed reduced performance due to suspected icing.

What would your response be?

Mine would be to declare an emergency, reduce power, descend to minimum safe altitude, while maintaining at least 40 knots above stall speed in an attempt to get to warmer air to melt or break off the ice.

Bad move or good move?

 

[sparebulb]

So the video summation seems to be correct.

Flight into heavy icing, lift gets reduced, power is increased along with angle of attack in an attempt to maintain altitude, pre stall buffeting occurs, wing stall occurs, with uneven lift a roll then yaw begins, spin is introduced and cannot be recovered from.

Let's say you found yourself in the exact same situation just prior to the wing stall or just when you observed reduced performance due to suspected icing.

What would your response be?

Mine would be to declare an emergency, reduce power, descend to minimum safe altitude, while maintaining at least 40 knots above stall speed in an attempt to get to warmer air to melt or break off the ice.

Bad move or good move?

It depends on the aircraft, but pretty much that is all you can do.

One note: adding power should reduce the AOA, at least temporarily. Lowering the AOA has a lesser well known benefit of keeping the ice accretion squarely on the front of the leading edge of the wing and not around the lower edge of the boot. I never flew a deiced piston, but a high speed climb is a big help on smaller turboprops when climbing through icing. I flew with many a copilot who queried me as to why I would use a high speed climb rather than elect to climb through the icing conditions as fast as possible. Unless the icing conditions are at a known and very thin height, I would rather for the accumulation to be squarely on the boot, so I will have a fighting chance. I saw several other guys have to turn around from a departure because they lost performance to where they couldn't climb and couldn't get a good break. Caravans had a reputation for building ice on the bottom of the wings and the cargo pod. I believe the pods were eventually deiced, which illustrates the effects of icing at a higher AOA.

Respectable jets have hot wings and the only thing you have to worry about it making sure the engines are spooled up enough to make enough hot air. You can often find yourself fuel critical when you have to carry a lot of thrust throughout the descent to the extent that sometimes you may have to hang the boards 100 miles out to keep a speed restriction. Straight winged Citations have deice boots. One exception that I can think of is the old Sabreliners. The didn't have boots or hot wings. They relied on pilot skill and judgement and the simple fact that when you aren't bothered with going fast, the compressibility of air on the leading edge usually builds enough heat and friction that is unfavorable for ice accretion. Plus, the Sabreliners used slats, which would be very hard to heat.

The ATR 72 has oodles of power, even at that altitude. We don't know yet whether they recognized their predicament in a timely manner or not. Regardless, in this scenario, full power, a lower altitude (if terrain allows) and insuring that the airspeed is at or above the minimum clean icing speed will/should insure success. If that speed is not sustainable, and a descent is not available due to terrain, flaps will have to be added and speed maintained above that specific speed. If ATC does not authorize a lower altitude, declare and emergency and descend anyway, just as you mentioned.

Many questions will be answered when they dig into the FDR. The ATR 72 has many lines of data and every flight control and system status will be recorded. It is possible that this crew did everything correctly, but my suspicions are that they didn't recognize their predicament before it bit them. I don't know what to hope for because it is all bad.

Have I answered it ad nauseum?

 

[Anti Federalist]

Have I answered it ad nauseum?

Yes, very much so, thanks.

When I used to fly on a regular basis, I would never turn down insight into accidents or wrecks like this.

That served me well in my maritime career as well.

Every week, for the safety meeting onboard, I'd take an incident a wreck or sinking and develop a 15 to 20 minute analysis of it to identify what went wrong and why.

The crew took to calling them my "safety sermons".

 

[sparebulb]

Before the internetz, I had a subscription to The NTSB Reporter. I think a lot of other pros did as well.

Decades ago, when I was a copilot at the commuter, a technical discussion in-flight was routinely settled by pulling out the manuals. This was done in the days without autopilots, short legs, and the manuals were several large bound volumes packed away in inconvenient locations.

The culture back then was that everyone had to be an expert on the aircraft. As the years passed, younger pilots were less and less interested in knowing the aircraft to that extent.

The new entrants to the industry have also latched on to Crew Resource Management, where they want equal say in every aspect of how the aircraft is operated.

CRM has been a trojan horse to mask DEI, lower standards, and wokeness. The early concepts were valid. (back when it was "Cockpit"RM) Now it is run like an encounter group, where every person's thoughts and feelings are validated.

 

[Brian4Liberty]

...

The new entrants to the industry have also latched on to Crew Resource Management, where they want equal say in every aspect of how the aircraft is operated.

CRM has been a trojan horse to mask DEI, lower standards, and wokeness. The early concepts were valid. (back when it was "Cockpit"RM) Now it is run like an encounter group, where every person's thoughts and feelings are validated.

Yeah, that has been going on for a long time in many industries. Everyone is equal, all opinions and input are valuable and must be considered, even implimented.

It's a recipe for failure and wasted resources.

 

[Anti Federalist]

Before the internetz, I had a subscription to The NTSB Reporter. I think a lot of other pros did as well.

Raises hand.

I sure as hell did...read that religiously.

There was also a section every month in "Flying" magazine, called "I Learned About Flying From That".

ETA - Lo and behold, here it is online.

https://www.flyingmag.com/tag/i-learned-about-flying-from-that/

 

[sparebulb]

Raises hand.

I sure as hell did...read that religiously.

There was also a section every month in "Flying" magazine, called "I Learned About Flying From That".

I think that responsible people gravitate toward the same mindset.

I guess that is called culture.

And it is changing.