Private Jet plane crashes in Florida | Hacker News Reader

Private Jet plane crashes in Florida

cbc.ca

61 pointshmokiguess113 comments

It looked like a missile https://streamable.com/lg0on2

The sound is just crazy and the images of the crash site seems somehow worse than what we've seen from e.g. Ukraine when a missile miss and slams into the ground.

A fully-fueled private jet is an inefficient missile, but it exceeds the raw chemical energy of most in-theater single-target tactical missiles (although the energy conversion is far less precise and efficient).

But yes, that's a lot of kinetic mass dead-stopping on a hard surface and 1 to 2 kiloliters of jet fuel.

Technically called a wet explosion. Fuel deflagration, not explosive detonation.

> when a missile miss and slams into the ground.

A lot of them are designed to explode before hitting the target for maximum damage.

The private jet carries up to 3.5 tons of fuel and weighs over 10 tons at take off. A Kalibr cruise missile is maximum 500kg of explosives and the heaviest variant is 2.3 tons over all.

Its not surprising at all that the jet makes a huge hole in the ground. Jet fuel is more energetic than RDX, while converting that energy slower. So both the chemical and kinetic energy is much higher with the jet then with a russian cruise missile. If anything the crater is surprisingly small.

The fuel would not have contributed to the crater. Fuel does not explode, not at the speed needed to form a crater. It requires oxygen. No matter how much fuel was present, there was not enough oxygen in the immediate vicinity of the crash to burn that much fuel.

The fact that there was a fire long after the impact shows the fuel was not burnt in the crash. Fuel hung around long enough to still be burning at least several seconds afterwards, long after the crater was formed. That is why it wasn't a missile. Missiles use high explosives (propellants and warheads) which burn up all at once to generally leave a non-burning crater.

Some back-of-napkin math yields a crater depth of a little under a meter ... which is in the ballpark of images.

aircraft (1.5m radius cylinder x 18m long) at 6700kg = 51.54 kg/m3 aircraft density... over ~1,500kg/m3 average soil density x aircraft 18m length = 0.63m

=.63m / 2-foot penetration below ground level... which is what the pictures show.

Soil is dense. Aircraft are marshmallows compared to soil.

> The fuel would not have contributed to the crater.

In the explosive sense, I agree. Depending on how much fuel they had, it could’ve been a decent percentage of the aircraft’s weight, though.

surely velocity and elasticity need to go into that calculation as well

Nope. Speed doesnt contribute to crater depth. Faster makes a wider crater, not a deeper one.

https://en.wikipedia.org/wiki/Impact_depth

When the object is near supersonic spèeds (throught the various materials) even the strenght of the materials becomes very secondary. A meteor made of sand makes the same crater as one made of stone.

Just to address the elephant in the room, that was also the "vulnerability" deliberately exploited in the 9/11 attacks.

What do you mean deliberately exploited? Given the information made available in the past 25 years, they didn't seem to plan for such engineering failure, it was more likely pure luck. I mean, crashing a plane, counting that the fuel would flow through the elevator shafts, still burning, and that it would soften the iron columns enough to make them buckle... it needs a competent team to plan that with certainty.

IIRC some the guys who hijacked the planes took flying lessons and were notoriously uninterested in takeoff and landing compared to steering, according to their instructors. They weren't very sophisticate.

I'll give you the benefit of the doubt, though. In a conspirational mindset, if it was a false flag operation (and it did help USA find support to rearrange the Middle East oil control, get rid of their old bomb stock, and a few other perks), a State certainly has the proper people to plan such scheme, and the actual hijackers would only need to know which face and height of the towers to hit, and at what angle and speed.

I meant the "vulnerability" that planes, especially early in the flight, also contain significant fuel that causes cascading damage beyond the impact.

I get that my comment probably didn't reach the "insightfulness" threshold for HN, but geez, go easy on me.

Ah, my bad. The word "vulnerability" threw me off.

I'd guess that wasn't deliberate also, since logistically, it was better to hijack the plane while it was in range of their target, and it had enough fuel to make it look like kidnapping instead of terrorism to delay the response. One can't ignore that a refueled plane weighs about 20-25% more, though.

I don't know how to break this to you, but the reason the 9/11 hijackers weren't interested in learning how to take off and land was because they were going to hijack the planes mid-air and then crash them, not land them. It wasn't because they weren't "sophisticated" and lacked interest.

What, that planes are heavy and move fast?

This is because there is more mass to the plane than most missiles. And that mass going those kinds of missile-like speeds is going to create quite a shockwave and crater. Contrary to what many people are saying, the fuel contributes very little to the crater size.

Citation: I'm a former airplane and missile guy.

Shouldn't the missile warhead contribute to the crater size though?

Learjet 60 is about 18 metres long. In one frame it's a little above the ground, in the next it's gone up to about halfway between the cockpit glass and the wing roots, and in the next it's gone.

At 30fps, I make that somewhere in the region of 1000mph.

The audio (don’t listen to it) has the pilot reporting the descent speed as 22,000 feet/min

I'm not planning on listening to it. I would expect that happened long before it hit the ground.

I’m not going to listen again to verify this but it felt like 20 seconds before they hit. The recording was only about a minute long.

ADS-B shows it as 32,000 fpm in the final 2 data records.

32,640 fpm is the maximum ADS-B can encode for vertical speed.

Quite likely it exceeded that, some sensible numbers I've seen suggest between 800 to 1000 km/h final speed at impact

I got called all kinds of wrong for picking 1000mph, but it's kind of the midpoint of the numbers I get from an 18-metre plane collapsing into the ground in a little over 1/30th of a second, single frame of video.

That's suspiciously close to the max value of a signed short int.

You'd think, but it's far stranger than that.

The actual VSI reading is taken either from barometric pressure or GNSS, and the source is flagged in a bit in the ADS-B packet. Then it's encoded in one of two forms in a 9-bit value with a single-bit sign.

If the 9-bit value is 0, there is no vertical speed available. Otherwise the vertical speed is encoded as +/-64 * (value - 1), giving a range from 0 to 510 for a range of bitfield values from 1 to 511.

Now this gives you a range in 64ft/min steps up to 32640ft/min. Most civilian high-performance aircraft will be in an absolutely screaming climb at around 10000ft/min and an 8000ft/min descent would be pretty aggressive - autopilots may drop into a 8000ish ft/min descent if there's a loss of cabin pressure, for example but 6000 would be considerably more comfortable. So even with your 9-bit value you've got enough resolution to show a fairly gentle climb (try staying below 1ft/sec climb or sink when flying by hand!) and something well in excess of what you'd normally want to experience.

64 * 512 = 32768

64 * 511 = 32704

64 * 510 = 32640

So that's just a bunch of zeros for the lower bits.

Interesting. Thanks for the explanation.

Yep. Picked 32640 because the last two values are, from my understanding, inconsistently handled by transmitters due to how far from norm they are.

Too many zeros or too many ones in a row can cause problems with DC balance on the transmitter and the receiver stages.

It's a bit like how the petrol gauge on your car is out to lunch below about 1/8th of a tank.

If you're doing 32000ft/min you're clearly going *muuuuch* too fast, either up or down, implausibly so.

Unless you're in a jet fighter aircraft in which case showing up correctly on flightradar24 is not your biggest worry.

there is dashcam footage from further away that gives a better indication of speed. It was fast but not supersonic.

The speed of sound in air at sea level is around 770mph, and I got 1000mph from 18 metres of plane disappearing into the ground in about a single frame of video.

Let's not argue over the approximate nature of "1000mph" given the measurement constraints.

I think it's pretty much a mercy that no-one aboard would have felt a thing in the last couple of dozen milliseconds.

Last transmission was 22k feet/second, which is 15k mph.

(I thought ATC's cool as a cucumber 'altitude your discretion' was 'interesting' – presumably a formality they need to offer to clear the aircraft, since clearly no discretion was involved.)

No it was feet per minute. 22,000 feet/second is almost orbital velocity.

Oops, thanks. Not familiar units for me, and I hadn't had a coffee.. that would be an absurd speed of course (nevermind to also have the composure to report it while experiencing it!).

> 22,000 feet/second is almost orbital velocity.

Solves one problem, gives you a different problem...

I once read a transcript of an incident where ATC advised an aircraft with multiple engine failures and no hydraulics "Emergency team in attendance, runway at your discretion".

The reply: "Oh you want me to be all fancy and make it a runway, do you? Well, we'll see..."

They got it pretty close to the runway and it all had a far happier ending than this one.

CBC article says vertical speed was 30,000 feet per minute, which is 550km/h or 150m/s.

it was also moving forward, not just downward.

Yes but that number is the vertical speed as it's measured in feet per minute.

That was probably not when it was the height of a telephone pole above the ground though.

341mph or 500ft/s

I might be going mad but 9 metres in 1/30s (half the plane in one frame) is 270m/s * 3600s = 972000m/h / 1000m/km = 972km/h or about 600mph?

I think your 1000 is the right ballpark but the units are wrong.

"No immediate reports of anyone on the ground injured or killed." If that's correct, the people in that silver car had the luckiest day of their lives.

It's unclear exactly what happened but I've heard some aviation experts talk about this and there are already some leading theories, which come down to two factors:

1. The so-called coffin corner [1] where the minimum safe speed for aerodynamic lift and the speed where the plane will stall narrows to a dangerously narrow window. This is caused in part because the speed of sound decreases at high altitude. Turbulence can throw you out of this window; and

2. It seems likely that control was lost because of ice. In released ATC recordings (which are awful to listen to, be warned) the pilot mentions ice. This is likely because of the bad weather over south Florida right now.

The pilot requested a new flight path and I believe tried to ascend from 35,000 feet to 37,000 feet and ended up in a spiral, banked at ~60 degrees, descending at ~30,000 feet per minute, crashing into the ground.

I'm not a pilot but I suspect there will be some element of this that is pilot error or at least could've been avoided and/or mitigated by an experienced pilot.

[1]: https://en.wikipedia.org/wiki/Coffin_corner_(aerodynamics)

It wasn't coffin corner. This was a Lear at reasonable altitudes, not a U2 at the edge of space. The death spiral suggest a loss of control authority. It is conceivable that one wing severely iced to the point of unrecoverable asymmetric lift but I think it was something more the icing. It might have lost part of its wing, or the controls on one wing locked into an unrecoverable position.

In the pictures, the flaps appear present but not extended. If they had been extended they would have ripped away at that speed. And they would not have been able to lower them after the overspeed began. I think the answer is in the control system. One or more control surfaces were doing something other than commanded.

Some images seem to indicate a loss/absence of the horizontal stabilizer, but it is hard to tell AI from real these days.

You can't say coffin corner wasn't a factor. As an example here was a Bombardier jet operating at 34,000 feet, well within it's safe operating envelope, that got hit by this because of the wake of an A380 [1].

35,000 to 37,000 feet, combined with turbulence from the weather, means this could come into play. We still don't know and may not know for some time, especially given the severity of the impact and what may or may not have survived. But you can't rule it out.

[1]: https://aviationweek.com/business-aviation/learning-test-pil...

But that isn't coffin corner. The "coffin" is a part of a flight envelope where departure results in near-certain horrible outcomes (ie too fast and wings fall off coupled with too slow and the resulting stall also rips the wings off). A lear or any other business jet is designed specifically to avoid any such things. It should stall, but not in any lethal way. And a lear is small enough that no storm should do things like rip bits off the aircraft. A thunderstorm will toss it around like a tennis ball in a washing machine, but wings/tails should not separate from the aircraft.

> Some images seem to indicate a loss/absence of the horizontal stabilizer, but it is hard to tell AI from real these days.

The descent rate seems the most likely cause of the missing stabilizer.

There will be many questions on why the pilot flew into the tops of what (at least on radar) appeared as a small-ish localized cell at that altitude. Vertical cloud development at those altitudes is a clear sign that whatever is inside is not going to be pretty.

Once the aircraft entered the conditions inside the storm, between the turbulence, icing, and up/down drafts it was likely an unrecoverable event.

yeah but they could/would definitely break during the descent so you can't know if that was the cause or the effect

That doesn't match what I'm seeing in the online discussions. I think most people who have a basic understanding of aviation or have been part of it would immediately see this as what happens when you fly a Learjet directly into a thunderstorm. The likely question is whether the first cause of loss of control was ice or something aerodynamic, like pushing the nose down in an updraft, causing the horizontal stabilizer to rip off.

In contrast, the coffin corner doesn't really have anything to do with this the plane would have been operating at standard enroute altitudes and speeds.

For context, I am in fact a pilot. I've read a little about what people are saying about this accident, but I've absolutely no new information or unique insight whatsoever.

I think as a pilot all we can say is “loss of control” but there’s many paths to that given available information.

Staying away from thunderstorms is a good rule of thumb no matter the aircraft and crew capabilities. Severe turbulence is expected within 20 miles of the visible portion of a severe thunderstorm.

AIM 7-1-26 paragraph c is in all caps:

NO FLIGHT PATH THROUGH AN AREA OF STRONG OR VERY STRONG RADAR ECHOES SEPARATED BY 20-30 MILES OR LESS MAY BE CONSIDERED FREE OF SEVERE TURBULENCE.

AIM 7-1-27 can be summarized as stay the fuck away from thunderstorms. This entire section is dedicated to avoidance.

https://www.faa.gov/air_traffic/publications/atpubs/aim_html...

See my other comment. This can't be ruled out yet, particularly because the pilot seemingly climbed to get above the weather where it would've been colder and the air less dense, narrowing the operating window so turbulence or a sudden dive could've spun out of control.

Whatever the cause, it seems like climbing to avoid turbulence in or near thunderstorm conditions when the pilot knows there is ice already was probably unwise. A more prudent course was probably to divert around it and/or to descend to de-ice the plane. If so, would this rise to the level of pilot error? I don't know but maybe.

Im not a pilot or meteorologist but from what others have said it seems that the plane would have been very cold from flying at 30k ft and if you fly into a thunderstorm like that where they have super saturated air just looking for any place to condense on, all that water would turn to ice immediatly on contact with the wings and as soon as the wings lose laminar flow they would stop providing any lift and the ice would increase weight and shift the center of gravity/rotation.

Im not sure how high the top of a thunderstorm can reach but if they could have gotten up and over the top above that 100%+ humidity before it had a chance to condense on the plane then i think that would have been the more prudent choice.

Generally in aviation more altitude is more safe. I think the only mistake was waiting too long to try and climb out of it rather than trying to climb over it to begin with. But im not a pilot so idk.

Icing was mentioned early in the ATC audio, then a request to increase altitude, then a comment that they encountered precipitation, implying the icing could get worse.

IANAP but the mention of precipitation points to conditions that could overwhelm anti-icing systems, which the Learjet was equipped with.

There's a thread on pprune about this incident. The usual mix of informed and less-informed speculation.

https://www.pprune.org/accidents-close-calls/674728-lear-60-...

a lot of the conversation on this thread seems to be around weather the horizontal stabilizer was missing

It’s amazing to me that this post already feels quite old. But then I realized it only happened yesterday. I just feel that way because in today’s world we have seven different dashcam or security camera video feeds popping up on Reddit or X or whatever within minutes of a news event like this.

Sad story in this case. The cockpit audio was quite chilling.

It's not even cockpit audio, it's just from ATC radio : - \

Is it possible to look up who owned the plane? Curious if it was a charter.

I looked it up in flight radar and it was a private owner with frequent flights to/from Little Rock and Washington.

I regret listening to the audio. There is nothing gained by hearing it.

It's a tough listen and I don't begrudge your regret listening to it, however I think the pilot did a remarkable job of communication information about speed and bank angle right to the end which will indeed help this investigation and hopefully prevent future incidents.

The nice thing about all the tapes and recorders is that when you know you're completely fucked, you can be damn near assured that the last things you choose to say will be preserved. Whether you make it a last message to your family, or as many technical details as you can throw out that might help the investigation and keep someone else from dying the same way. In a way, documenting as much as you can of your impending death becomes your final task.

Yep - some people are being paid to listen to that, but I'm not.

I always ignore warnings like this and am usually never affected by such audio but I feel psychologically scarred by it

Highly recommend anyone reading to not make the same mistake

I have not and did not intend to, but you made me curious. Why should I not listen to it?

If you have an ounce of empathy, hearing someone scream in terror and narrate their final moments will affect you negatively. The pilot is aware of the situation the entire time.

In every thread on this not a single person I have expressed anything other than regret for having heard it

Yeah, usually i listen to stuff like that. I watch a lot of those youtube videos where pilots break down plane crashes from their perspective and sometimes you hear the audio from inside the cockpit. Usually that stuff doesnt affect me too bad but im fighting to resist the urge to listen.

I think the worst crash i learned about was when maintenance let a rear stabilizer go 20 years without so much as a checkup and the screw that controls the positioning of the rear stabilizer ran out of lube and stripped all the threads off mid flight causing the plane to lose all pitch control.

You could really hear the emotion in the pilots voice as they realized they were now riding a terrifying rollercoaster with no control over their altitude.

I actually think they may have survived which is insane, they had to try to control the pitch of the plane with the engine throttles, if you start going down then increase engines until you start going up again and if you go up to fast then decrease throttle.

Absolute insanity, i think they lived but if that had happened in the middle of a thunder storm while the plane was covered in ice there would be no chance.

It seems i combined two different incidents in my memory, the one where the pilot controled the plane via engine throttle was united airlines flight 232, out of 285 passengers and 11 crew 175 passengers and 10 crew survived the crash landing.

The other incident with loss of rear stabilizer control was alaska airlines flight 261 and all 88 people on board died when the plane crashed in the pacific ocean.

It might also affect you positively. Trying to avoid all exposure to the realities of death is not only unhealthy but also futile since in the end it comes for us all. Memento mori.

> In every thread on this not a single person I have expressed anything other than regret for having heard it

That's because most people who don't feel the need to be overdramatic also don't need to feel the need to comment about it.

It's just hard on the soul. You hear someone professional, who we'd usually look to as the adult in the room, quickly unraveling.

She goes from the confident pilot speak to panicked reports to starting to scream and hyperventilate, while doing her best to recover and communicate what's happening to the tower. At some point you hear them acknowledge that it's too late and they're all going to die. And then one last scream before suddenly cutting out.

It's just that gut-wrenching empathy and feeling of helplessness.

I would personally say that people should listen to this stuff, though. Life is hard and fragile, and even though it's hard, empathizing with this suffering makes sure we understand the real costs of our mistakes.

I saw way too many dismiss a million deaths by COVID. So many people bat their eyes at 100 people dying in a plane crash now. If they heard the recordings of these kinds of last moments, I think we'd be at less risk of our (moral/procedural) standards slipping.

Yes i fully agree with you, because of the warnings i was very hesitant to listen to the audio and after learning it was a woman pilot i was even more hesitant. But i have now heard it and it was absolutely awful but not any worse than some of the other crash audio i have listened to. I believe its important for the living to carry the burden of the dead. The dead deserve to have their story told and listened to and the living owe at least that much to the dead.

He is being overdramatic. It's pretty bening as far as what you can find on the Internet goes.

Don’t just crash. Was full throttle into the ground, by the looks of it.

Reading what the pilot said is pretty harrowing. We know a lot from what the pilot already said over the radio (and maybe that's the best info we'll get, are there any remains left?)

> is there any remains left

If there is, seems they're deep under the ground as it nosedove straight into the ground and essentially disappeared, the crater showed almost no debris at all. People been guessing on reddit that everything just got "instantly pulverized" which I doubt somewhat, the shape of the frame is perfect for it shooting into the ground so I'm guessing they'll spend some weeks digging and eventually find the wreck.

Edit: Since I can't respond to my children:

> This kind of impact in fact has tendency to turn aircraft into powder

How often? A similar crash that comes to mind is https://www.washingtonpost.com/transportation/2023/06/05/dc-... where they did recover actual bodies, even if the impact was near-vertical and seemingly faster than this case.

What specific cases are you thinking about where everything "instantly pulverized"?

This kind of impact in fact has tendency to turn aircraft into powder

Er, no. You’re greatly underestimating or misunderstanding the forces involved here. “Instantly pulverized” barely even begins to describe it.

In the video in the thread, it seems to go from fully extended airplane to pancake in about two frames, which is, again, harrowing, horrible.

It's basically airframe to dust in three frames, so maybe a 1/20th of a second. The moment of impact would have been mercifully quick.

Nerve impulses travel at about 120 m/s, max, and that's along long myelated runs. Cohering raw pain signal into the experience of pain takes at least 150 msec according to the best measurements we have on the topic.

The vertical speed of the plane alone at last reported speed indication exceeds the speed of neuron transmission along myelated nerve tissue. This impact event is mechanically impossible to feel.

Unfortunately, even at a descent rate of 30,000 feet per minute you've got a full minute to anticipate the impact before you don't feel it.

https://x.com/Nalanda_index/status/2117064398166777927

The crater shows the road was destroyed. Aircraft skins are much thinner and less robust than road coverings.

> A similar crash that comes to mind ... where they did recover actual bodies, even if the impact was near-vertical and seemingly faster than this case.

Well, just looking at the article, I see trees, which tend to slow things down and can cause a plane to break up.

Mythbusters did this with a sled going "only" 650 mph and I would call the result instantly (but not entirely) pulverized:

https://youtu.be/aSVfYwdGSsQ?t=132

High-speed camera footage of rocket sleds and fuselage testing is fascinating stuff.

You can see the macroscopic deformation fail to transit the body of the impacting object with enough speed to make gross deformation happen as it collides. The front of the rocket body is literally turning to a vapor at the impact site, and the tail assembly is 100% fine.

You would never know a plane caused that crater since there was so little left. Hopefully it puts to bed the conspiracy theories of the plane that crashed into the pentagon. Doubt it though.

Judging by what is circulating in Twitter today it mostly flared them up

Very little will be left considering the impact speed. Even if the aircraft was equipped with a flight data recorder (black box) then its structural limits were probably exceeded.

an SD card in foam in a thick metal sphere, like a bowling ball, would survive this, could be used as a backup to the main one.

How do you write to the sdcard while its packed in its foam helmet? If you put a little computer in there then it would have more mass and metal to smash around on impact. Maybe like a tiny usb card reader and a long data cable?

I wonder if running the data cable through the foam would cause problems like letting fire/fuel/water through the helmet and disolve/melt the plastics or if you whip a cable hard enough it can cut right through things like a weed wacker.

there are tiny chip size wireless receivers for small distances like this, you would need some sort of window through the metal, or a tiny antenna inserted through the ball shell and the wireless covers just the inside

or just ultra-thin wires connecting the memory to the outside. the ultra-thin wire will just snap and it's too light to cause damage by whipping around

the big problem is kinetic impact, fire/fuel/water would be easy to solve, for example fire requires oxygen which will have difficulties getting inside through a tiny hole, and I'm sure there is some metal alloy which doesn't melt in typical plane fuel fire temperatures

The speculated final velocity at time of impact greatly exceeded design parameters for black box survivability so...

Forward velocity is proportional to lift, assuming your lifting surfaces still work. If you're stalling, standard practice is to apply power and get the nose down so that gravity and engine thrust are working in your favor to put air back under your wings.

In this case though, it sounds like the icing was much worse than they thought and fatally compromised the aerodynamics of the wings, and then the overspeed would have torn at the wings and fuselage... In that circumstance, you're no longer flying a plane, you're riding a javelin.

Training would generally still encourage the pilots to apply power; in the worst-case scenario (here), failing to apply power would not have made the crash survivably slower, so the sum total of best bad actions is still "Apply power and hope you're not in the worst-case scenario."

Question from someone who knows nothing about aviation, is it possible that the pilot did that knowing they were doomed?

It’s easy to get disoriented and accidentally accelerate into the ground, yes, (which is basically the procedure in a stall to get lift back anyway) but based on the ATC recording they knew what was going on and just dropped out of the sky.

The pilots were trying to save the plane up until the last moments. They declared an overspeed condition soon after they ran into trouble, so they were aware of it, but did not intentionally cause it.

And if they were so iced over that control surfaces weren't responding and the wings were no longer generating lift, at that point they were well past the "Anything we do is going to have any effect whatsoever on the future" point.

I don't intend to listen to the audio. Second-hand, it sounds as though they did absolutely everything they could after hitting the cell, and the only way to have avoided this whole situation was "Don't fly that route that day."

... a problem that, in general, we see more often in private-jet and single-engine aviation than commercial-carrier aviation. Far more incentives to make a really, really bad call... And when the bad call happens, the Venn diagram of victims and responsible parties tends to have a lot more overlap, so there's, practically speaking, fewer consequences to discourage such bad decisionmaking in the future (can't meaningfully punish the dead, and the dead can't learn from experience what a bad call "smells" like on the lead-up to it).

I don't agree they had no way to avoid this. Every accident is a chain of mistakes, gaps or mechanical issues. We don't know the whole story here, but I do know that planes of this class are not given up for dead when they hit a surprise weather system. If they are, that means they missed something earlier - weather radar was misinterpreted or a bad judgment call was made.

That's my opinion given current information - only way to avoid this was to not put the plane in that storm.

Right - I misread your message. Yes they needed to avoid that storm and should have had chances to do so.

Anything is is possible, but Mach tuck may have been an issue [1], but it slo may have been actual flight controls.

https://en.wikipedia.org/wiki/Mach_tuck

The italicised paragraph at the start of that article is not what I was expecting to read...

The Mach tuck recovery is counter intuitive, and could lead to further overspeed and forces exceeding design tolerances.

Another possibility is flutter. I read overspeed and icing mentioned by a pilot in the transcript. Therefore I think of those two elements conspiring in an edge case resulting in forces exceeding design limits, something broke, and made recovery impossible.

But anyway, the investigation will likely answer these questions.

agree. some other forums have alluded them losing their horizontal stabilizer (based off it not being in some stills of the plane crashing) - so the something broke case may also be a big element.

No, throttle was surely idle. The plane was just flying vertically. In a dive, you have a 1:1 thrust/weight ratio and can go extremely fast. The pilot reported an overspeed warning on the audio (which people should not listen to if they're sensitive).

My gut says this is a sudden icing incident. Folks are pointing out that they appear to have flown straight into the center of a cell at altitude. A developing thunderstorm is MUCH warmer than the surrounding air, because the water condensing out of the rising/cooling mass buffers the temperature (due to heat of fusion). It can even be supersaturated ("higher than 100% humidity") if this happens fast enough. The water vapor is just desperate for a nucleation site to condense on.

So you have a situation where a metal jet body that is maybe 30C colder than the medium suddenly flies through this soup. It can ice over in seconds to minutes, and the plane ends up with bricks for wings and much more weight than it was designed for, and simply can't stay in the air. Then it dives inexorably.

Yep, the radio calls said something about -47C temp, them already fighting icing and “precipitation” ahead.

I don't want to be a naysayer, but what is this doing on HN?

Meh, variety is the spice of life.

Imagine your loved ones die like this and you find out watching these mouth breathing morons swarming the crash site, exclaiming "bruh!" and "bro!" on the news. The average person's mind is a real wasteland.

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