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March 22

Stillbirth

What could be responsible for a baby dying in the womb? — Preceding unsigned comment added by 2A03:2880:30FF:10:0:0:FACE:B00C (talk) 18:46, 22 March 2022 (UTC)[reply]

Have you looked at the Stillbirth article? There is also an UK NHS page here. Hope that might help. Martinevans123 (talk) 19:04, 22 March 2022 (UTC)[reply]

What are the implications, if an airplane crashes in a vertical nose-dive descent?

Re: China Eastern Airlines Flight 5735. The article states: ... footage depicts the plane in a nose first vertical descent. What is the significance and/or implications of a near-vertical nose-first descent? In other words, what does that "fact" tell investigators? Thanks. Joseph A. Spadaro (talk) 18:49, 22 March 2022 (UTC)[reply]

Even if all engine power is removed from a Boeing 737, so that any autopilot mode is disengaged, during a straight and level cruise, if the aircraft surfaces remain as set, the aircraft should be able to glide for about 60 miles? A nose dive suggests either catastrophic failure of the control surfaces or that the aircraft has been intentionally flown into that dive profile? Martinevans123 (talk) 19:02, 22 March 2022 (UTC)[reply]

Hmmmmm ... thanks. In other words, it could/would be a (possible) sign of a pilot suicide? Joseph A. Spadaro (talk) 19:32, 22 March 2022 (UTC)[reply]

I wouldn't like to speculate. But if the aircraft in question hit the ground, such a scenario might not be easily proved or disproved by the FDR data, or even the CVR data. Martinevans123 (talk) 19:56, 22 March 2022 (UTC)[reply]

Thanks. I am not referring to this specific case, but just to airplane crashes in general. If investigators see a vertical nose-dive descent ... does that trigger the thought that it's a possible pilot's (or some other on-board individual's) suicide? Thanks. Joseph A. Spadaro (talk) 20:03, 22 March 2022 (UTC)[reply]

Unless the aircraft has been blown up by a bomb, and it's just fragments that are falling, I think vertical descents are rare in plane crashes. But then pilot suicide is also quite rare. Martinevans123 (talk) 20:36, 22 March 2022 (UTC)[reply]

~~Based on my extensive expertise from watching airplane accident TV shows, it is very difficult to get a modern airliner to go vertical and remain vertical unless it is deliberate.~~ Also see Suicide by pilot. Clarityfiend (talk) 23:29, 22 March 2022 (UTC)[reply]

The general description of the crash reminds me of USAir Flight 427, which was a "hard rudder over" event. --←Baseball Bugs ^{What's up, Doc?} carrots→ 21:41, 22 March 2022 (UTC)[reply]

Possibly so. Even that was only pitched 80° nose-down and banked 60° left. Martinevans123 (talk) 22:06, 22 March 2022 (UTC)[reply]

Reading the comment above by Clarityfiend made me think of another (somewhat related) question. Is there any valid or legitimate reason for a pilot to deliberately engage in a nose-first vertical descent? Or maybe ascent? Is there any scenario in which that would be "proper" or appropriate? I am not talking about engaging in a nose-first vertical descent, until the pilot crashes (or lands) the plane into the ground or the ocean or a mountain. I guess I mean for a brief temporary time-frame, to avoid some problem or collision or weather or whatever emergency? Would there ever be such a scenario that might call for such a maneuver? Thanks. Joseph A. Spadaro (talk) 00:52, 23 March 2022 (UTC)[reply]

I was thinking of ValuJet Airlines Flight 592, but now that I found the article, that was due to mechanical failure, not murder/suicide, so ignore the first part of what I said. Clarityfiend (talk) 02:40, 23 March 2022 (UTC)[reply]

There was also Indonesia AirAsia Flight 8501. While this was more complicated than just a sudden descend, it did involved a stall and rapid descent. The maximum descent rate is only about 2/3 of that of the recent crash however it was still fairly high.

Plesel, possibly spatially disoriented due to the roll sensation, over-corrected twice: first by making a sharp right bank input and then a sharp left bank input. After that, at 06:17, Plesel made a nose-up input on his side-stick, causing the aircraft to enter a steep climb at a 24-degree nose-up pitch. In just 54 seconds, the aircraft climbed from FL 320 to 38,500 feet (11,700 m), exceeding a climb rate of 10,000 feet per minute (51 m/s). It then entered a stall, at around 06:17:40, descending at a rate of up to 20,000 feet per minute (100 m/s). The aircraft also began a turn to the left, forming at least one complete circle before disappearing from radar at 06:18:44. At 06:20:35 the flight data recorder stopped recording. The CVR stopped recording one second later, at 06:20:36. The aircraft crashed into the Java Sea and was destroyed.

I have no idea what the nose pitch etc would have been like during the descent although do find some sources suggesting it may have hit the water nose first. Nil Einne (talk) 04:46, 23 March 2022 (UTC)[reply]

Some more reading found Alaska Airlines Flight 261:

At 16:09 (00:09 UTC), the flight crew successfully used the primary trim system to unjam the stuck horizontal stabilizer. Upon being freed, however, it quickly moved to an extreme "nose-down" position, forcing the aircraft into an almost vertical nosedive. The plane dropped from about 31,500 ft (9,600 m) to between 23,000 and 24,000 ft (7,000 and 7,300 m) in around 80 seconds. Both pilots struggled together to regain control of the aircraft, and only by pulling with 130 to 140 lb (580 to 620 N) on the controls did the flight crew stop the 6,000 ft/min (1,800 m/min) descent of the aircraft and stabilize the MD-83 at roughly 24,400 ft (7,400 m).

and

Beginning at 16:19 (00:19 UTC), the CVR recorded the sounds of at least four distinct "thumps", followed 17 seconds later by an "extremely loud noise", as the overstrained jackscrew assembly failed completely and the jackscrew separated from the acme nut holding it in place. As a result, the horizontal stabilizer failed at 17,800 feet (5,400 m) and the aircraft rapidly pitched over into a dive while rolling to the left. The crippled plane had been given a block altitude, and several aircraft in the vicinity had been alerted by ATC to maintain visual contact with the stricken jet. These aircraft immediately contacted the controller. One pilot radioed, "That plane has just started to do a big huge plunge." Another reported, "Yes sir, ah, I concur. He is, uh, definitely in a nose down, uh, position, descending quite rapidly."

and

The CVR transcript reveals the pilots' continuous attempts for the duration of the dive to regain control of the aircraft. After the jackscrew failed, the plane pitched down -70 degrees and was rolling over to the left. Performing an upset recovery maneuver, the captain commanded to "push and roll, push and roll," managing to increase the pitch to -28 degrees, he stated "ok, we are inverted...and now we gotta get it." Over the next minute, completely inverted and still diving at -9 degrees pitch, the crew struggled to roll the plane,

I also found Atlas Air Flight 3591 it was on approach but did enter what is a called a nose dive. And Adam Air Flight 574:

By the time the pilots noticed the situation, the bank angle had reached 100° with almost 60° nose down attitude. Contrary to the correct recovery procedure, the pilots did not level the wings before trying to regain pitch control. The aircraft reached 490 knots (910 km/h) at the end of the recording, in excess of the aircraft's maximum operating speed (400 knots (740 km/h; 460 mph)). The descent rate varied during the fatal dive, with a maximum recorded value of 53,760 feet per minute, roughly (531 knots (983 km/h; 611 mph)). The tailplane suffered a structural failure twenty seconds prior to the end of the recording, at which time the investigators concluded the aircraft was in a "critically unrecoverable state".

Some also mention Flash Airlines Flight 604 which is called a nose-dive although at least from the description in our article, it doesn't sound that similar:

At this point the aircraft entered a right bank of 40 degrees. When the bank reached 50 degrees, First Officer Al-Shaafei called out "overbank," indicating that the aircraft's bank was becoming dangerous. The bank angle increased rapidly until it reached 111 degrees at which point the aircraft entered a stall. It crashed into the Red Sea at 04:45 EET (02:45 UTC), just three minutes after takeoff, at a speed of 412 knots (474 mph) at a right bank angle of 24 degrees and at a nose-down angle of 24 degrees. All 148 people on board perished.[1]

Nil Einne (talk) 05:50, 23 March 2022 (UTC)[reply]

There is also [1] [2] although it was only briefly by comparison. Nil Einne (talk) 06:29, 23 March 2022 (UTC)[reply]

Is there any valid or legitimate reason for a pilot to deliberately engage in a nose-first vertical descent? Not really. At least, not to a point so fast like this that there wouldn't have been any contact with ATC. Even emergency descents (say, due to depressurisation) would not be conducted at a 30000 fpm rate (and consequently, certainly not at a full nose down attitude); and in any case flight manuals recommend maintaining a safe speed and common sense dictates one should retain control of the aircraft while doing so. Modern jetliners are wonderful machines, but they are not aerobatic or fighter aircraft, and such extreme maneuvers are not something the plane is designed for, and even less so of a good idea if there are actually passengers aboard. Short of the pilot deliberately doing so, there do remain some options, such as critical damage to a flight control surface (or it being forced into an inappropriate position); or an in-flight upset, caused either by heavy turbulence or a combination of other factors (makes me think of China Airlines Flight 006 - although the pilots there managed to recover safely, although the plane was badly damaged). The more precise data from FR24 suggests the plane levelled off, at least momentarily, but without information regarding it's bank angle or pitch at that time, it is impossible to know whether this was simply the trajectory followed by an otherwise uncontrollable plane, or whether it was an unsuccessful attempt by pilots to regain control, or even if this was indeed a suicide by pilot and somebody was trying to wrestle the controls from him. RandomCanadian (talk / contribs) 05:13, 23 March 2022 (UTC)[reply]

In the above post, RandomCanadian uses the term FR24. What does that refer to? Is it a flight? A flight recorder? What do the letters (FR) and the numbers (24) stand for? Thanks. Joseph A. Spadaro (talk) 17:58, 23 March 2022 (UTC)[reply]

@Joseph A. Spadaro: Flightradar24. 199.208.172.35 (talk) 19:40, 23 March 2022 (UTC)[reply]

Looks like it was about to approach destination airport, and I heard (unconfirmed) there were 3 crew members on the flight deck, it also briefly leveled / climbed, so this might not be intentional, or maybe a fight/struggle among the pilots, or something that disabled the entire crew, but don't quote me on this. A bad stall that's not recovered from could end up in a nose dive, especially if the control surfaces create more drag to the rear of the airframe. Although from 30 K, with enough airspeed, as long as you have controls, there's a fair chance of recovery. I find the lack of reporting of any radio communication quite strange however. GeorgiaDC (talk) 09:23, 23 March 2022 (UTC)[reply]

If the "black boxes" managed to survive the impact, they might tell the story. Whether the Chinese government sees fit to reveal that story, remains to be seen. --←Baseball Bugs ^{What's up, Doc?} carrots→ 11:43, 23 March 2022 (UTC)[reply]

The one box they have found is so badly damaged it's unclear if it was the FDR or the CVR. Whatever story it does tell might well be ambiguous. But I think it's highly unlikely we'll get to see any personal information on the pilot or other crew. Martinevans123 (talk) 11:47, 23 March 2022 (UTC)[reply]

Reports say it actually had 3 pilots. FR24 charts. Plane doesn't appear to have stalled. Looking at the vertical rate, there appears to be attempt to reverse from dive to climb, over 60 sec or so. Combining ground and vertical speeds, the actual dive wasn't necessarily straight down, more like 45 degrees. Here's angle 1, appears almost vertical. But here's angle 2, less vertical. Of course, a lot talk at this point about angle 1, but it could be misleading. I also can't make out any wings, blurry as the footages are. GeorgiaDC (talk) 23:00, 23 March 2022 (UTC)[reply]

Thanks, all. Joseph A. Spadaro (talk) 20:30, 27 March 2022 (UTC)[reply]

Resolved