Posts about: "Preliminary Report" [Posts: 277 Pages: 14]

There is a CMR on the 787 to remove and do an inspection of the thrust lever mechanisms on a periodic basis - I don't know (or at least remember) the interval, but I'd expect it to be in the 20,000-30,000 hr. range.
This is related to the FAA preoccupation with Uncontrollable High Thrust and the potential for a mechanical failure in the thrust lever mechanism to cause UHT.

As previously explained, the fuel control switches are a 'break before make' design - with a nominal gap between the two states of about 50ms.

Dani, the reason your posts regarding nearly simultaneous switch failures keep getting deleted is that this exact scenario has been repeatedly raised in the three Air India accident threads - and then thoroughly discounted and dismissed by people who - unlike you - are actual experts on the subject and/or pilots who have regularly used them. That your latest attempt to resurrect this hugely improbable scenario has remained and resulted in another 4 or 5 pages of hamster wheel discussion suggests to me that the mods have simply given up on this thread...

The recorded switch position data, the recorded engine performance data, the aircraft performance and trajectory after take off, the RAT deployment and open/ing APU inlet, the cockpit voice recording that has been selectively and carefully paraphrased in the preliminary report and the physical and electrical design and separation of the switches and the wiring for each system prove, to whatever standard of proof anyone wants to nominate, that BOTH fuel cut off switches were physically switched OFF 'shortly' after take off, then BOTH switches were physically switched back ON 'shortly' thereafter.

Give the FSC switch/wiring defect theory away, hamsters.

The ultimate assessment of the contents of the preliminary report is some time off in the future (contents, here meaning what is included and what is not). That being said, the comparison to the several briefings by NTSB in the wake of the 29 January 2025 midair collision at DCA is less valid than might at first seem to be the case.

First, the DCA collision occurred against the backdrop of significant weaknesses in the United States ATC system. The accident itself may have involved acts or omissions by the Army helicopter pilot or pilots, so there is that similarity in a general sense. But although a non-aviator, I did understand the many statements on the threads and in the general media about the difficulty of "visual separation" at night, particularly in the D.C. area and in the approach corridors to DCA. This is quite unlike the surpirse and/or disbelief that an experienced airline aviator would move fuel control switches to cutout at or nearly at the time of rotation. So the nature of the acts or omissions in question is quite different.

Second, it obviously occurred at Washington, D.C.'s close-in airport, which has been such a focal point of Congressional "air commuters".

There also is a difference in the likely litigation courses the two accidents will follow. On the premise that the WSJ report aligns with what appears to be the consensus on this thread - namely that the PM moved the switches although no one now knows why - and then reasoning further from that premise, the litigation to be faced by Air India will be considerable. I do not know the Law of India whatsoever, but under the Montreal Convention system for liability determinations and damages, I think it is a very easy straightforward assessment to say that the airline is going to face intense litigation challenges. In that light, the families will have their day in court (I mean, even without knowing Law of India, I think that's safe to say). Going beyond what - if I am reading and understanding the posters with actual significant investigation experience correctly - is the formal or nominal charge of the AAIB in this matter is not required in order to help the families. (And how bad would it be for them if the AAIB had to retract or materially change some information released ahead of determinations with certainty?)

Not least, in the DCA accident the legal landscape is quite diffrerent. Without rehashing the (perhaps tedious) posts I put on the DCA thread, the scope of available legal relief is quite limited under applicable federal law (just for reference, the "discretionary function exception" to the allowance to sue federal entities will almost certainly limit the scope of recoveries available from the Army or FAA/Dept of Transportation; the airline can be sued but it will be, in my not-so-hmo, ridiculous and mercenary to do so, as the CRJ and its tragically ill-fated crew had done nothing wrong).

Somewhat relatedly, on the WSJ article, while its sources are unnamed, I'm trying to recall a single article published in that newspaper (including online) about a major aviation incident which later was shown to have been inaccurate. Maybe there are one or more examples. Generally The Air Current's publisher got a very good start.

I have not posted on here in many years, but I feel compelled to do so now. I am a current 787 pilot and I have previously flown most Boeing types and an Airbus too. I also have an extensive background and qualifications in human factors, training and assessment. Before anybody reads any further, perhaps acquaint yourself with the notion of Occam's razor. That is, the simplest explanation is the most likely explanation. I was certain that after the preliminary report was released the preposterous conspiracy theories would finally cease, but no! It's 2025 and humans can no longer help themselves. In my opinion the captain committed suicide here. Simple.

To those suggesting an electrical phantom turned the fuel control switches off without them moving: no. Ask yourselves this: what made one pilot (PF and F/O in my opinion) ask the other "why did you cut off?" Firstly, some context. The 787 fuel control switches make a VERY distinct metallic *CLICK* sound as they are operated. EVERY 787 pilot knows it and won't forget it. It is audible even at high thrust settings owing to the 787's exceptionally quiet engines and cockpit. After rotation the pilot flying is fixated on the HUD; rotating towards the TOGA reference line (~12 degrees pitch attitude) and putting the flight path vector over the flight guidance cue. One hand would be on the control column and the other on the thrust levers. Alternatively he could have had both hands on the control column. In either scenario, the pilot flying's (again, my opinion the F/O's) inboard arm would block his peripheral view (he's focused on the HUD, remember) of the center pedestal and the fuel control switches. HE WOULD NOT SEE THE PM TURN THE FUEL CONTROL SWITCHES OFF. Ipso facto. We know the F/O was PF from the report. If the F/O stopped flying the aircraft and reached down to move the FCS from cutoff to run the captain would've plainly seen the whole thing. I can't imagine "why did you cutoff?" would be his words of choice! More like "WTF ARE YOU DOING?!?" More to the point, if the PF (F/O) did stop flying and reach down to cut one engine off, the captain would have had time to either stop him flicking the second FCS off or at least quickly flick them both back to run and potentially save the day. This plainly did not happen. So it was almost certainly the PM (Capt) that moved the fuel control switches.

So what would make the PF ask the PM "why did you cut off?" if he couldn't see it happen? You would never assume with a loss of thrust that the switches had been turned off. Never. It's not a procedure. It's not a thing. Bird strike? Sure. Fuel Contam? Maybe. But the point is, in the heat of battle at 150 odd feet, you'd never jump to the conclusion that the fuel control switches were off. Never. So what triggered the PF asking the PM why he cutoff? Because he HEARD the fuel control switches move from run to cutoff, that is why. He heard those distinctive *CLICK* sounds (and yes, you can easily flick them both in less than a second FWIW) followed by the engines immediately rolling back. He would then have looked down at the switches and noticed they were in cutoff. The point to be made here is that the switches were moved by the captain. They made their distinct sound. There were no phantoms. They cannot move on their own. They didn't simultaneously fail. This drew the PF's attention away from flying and triggered the question "why did you cutoff"?

Inadvertent selection of the wrong switches? No. The PM was a training captain with thousands of hours experience on the jet. I asked one of our most experienced examiners how many times he'd seen that done. The answer was "zero". Even the stab switches next to them. They're red, guarded and are of a completely different shape and operation. Gear or flap? Come on. I think we're starting to stretch things a bit now. EVEN IF it was inadvertent switching. The INSTANT you'd made that error, you'd go "oh whoops", and flick them back to run. I know startle... I teach it. This is different. You don't flick the fuel control switches off, hear the engines roll back and sit there wondering what happened for 10 seconds AFTER THE F/O JUST ASKED YOU IF YOU CUTOFF! You did something that had an instant effect on the flight. The report indicates that "why did you cutoff" was asked just after both engines rolled back. But it took another 10 seconds to flick the FCS' back to run. If it was inadvertent, the instant the other pilot called out your error you'd correct it. The report makes it clear that there was 10 seconds between that happening. 10 seconds is a LIFETIME in that situation. The training captain knew what he was doing. He only switched the FCS' back to run once he knew it was moot.

So, why did he respond that he didn't move the switches? As per other input from people on here, when people are suicidal they often want to throw authorities off their trail. Or maybe he wanted to confuse the F/O so he didn't flick them back to run himself, or to just buy himself more time while the F/O tried to wrap his head around things? Maybe he didn't want the F/O to die knowing it was a suicide mission. Maybe we'll find out more in the final report or police investigation if things proceed that way. Maybe we'll never know.

I acknowledge that this is my opinion and of course there could be things we don't yet know about, but I must say I'm surprised that some of the theories on this professional pilot forum are no more coherent or logical than those being sprouted on social media.

I'm sensing that the Journal, while not immune whatsoever to commercial pressures, is well-sourced.

From the article: "The preliminary details have fueled the belief among some U.S. officials that criminal authorities should review the matter, as would likely be the case if the crash had occurred on American soil, people familiar with the matter said." This assertion, stated without attribution, is fairly viewed as having unknown credibility.

But it also might be understood differently when read in a context of the entire reporting which includes these two quite specifically attributed statements:
From the article: "An NTSB spokesman said that [NTSB Chair Jennifer] Homendy has been fully briefed on all aspects of the Air India investigation, including the cockpit voice recording and details from the flight data recorder. Homendy said her goal in working with Indian authorities was 'to quickly determine whether the crash presented any immediate safety concerns to the traveling public.'\x94 (internal quotation as in article)
........
From the article: "The Indian authorities\x92 preliminary report finding that the fuel control switches were flipped in succession, one second apart, suggested a deliberate act, according to Ben Berman, a former senior NTSB official who helped oversee the U.S.-led investigation into the crash of EgyptAir Flight 990 in 1999.

Berman said that, prior to the engines\x92 fuel being cut, the report didn\x92t suggest anything out of the ordinary for what should have been a routine takeoff and climb-out. 'There was nothing to prompt the crew to perform emergency procedures, become stressed, or do anything except rotate the nose up and retract the landing gear, like they had done so many times before,' Berman said." (internal quotation as in article)

The Air Current's reporting just prior to release of the preliminary report - based on unnamed sources possibly with close access to the AAIB - turned out to have been correct. Would NTSB have offered the comments it did, if it believed the Journal was about to publish stuff it was just making up?

Edit: the WSJ also, on Wednesday, published a column by one of its regular staff columnists who thinks pilotless airliners are inevitable and would be a much better system architecture. Perhaps in publishing this reporting about the Air India accident the Journal is hoping to preserve credibility among the industry and regulators, despite the nonsense (imho) of that part of the column (most of it concerns the apparent cause of the accident, which - as some post many many pages ago predicted would occur - becomes supposed justification for Captain HAL).

I just checked the last one that was linked here: https://www.wsj.com/business/airline...crash-148b7e02 / https://archive.is/pembL That's two errors, or at least very misleading statements.

I think everyone agrees that the preliminary report contains sufficient evidence to start a criminal investigation. What this thread is in two minds about is whether the outcome of a criminal investigation is a foregone conclusion.

That's better than being at the mercy of speculation from the AAIB.

It's easy to go, "it must be suicide, there's nothing else in the preliminary report that explains it". Well, the things that might turn out to be a factor are not in the preliminary report because they're still being investigated. Fuel samples. The switches themselves, which suffered fire damage. A thorough understanding what can cause the transitions logged on the EAFR, and what did cause them.

YOU are one of the sources of "speculation of unknown origin".

This thread could be two posts long instead of 64 pages and counting; the post with the preliminary report attached and this post above from a professional pilot.

There are good, valid reasons for the ICAO accident investigation rules - and one of those rules says they'd don't release information until it is properly vetted and validated. As I posted previously, the preliminary report actually had more data that most - it would have been very easy for them to have simply said that the engines quit - one second apart - starting 3 seconds after liftoff. Instead they added detail, including a brief synopsis of a pilot conversation regarding the fuel switches. All this is factual. What they don't release is non vetted information and speculation - such as who moved the switches and why - because that's still being investigated.
Early releases of unvetted data can not only cause unproductive public reactions, it can result in external pressures being applied to the investigative team that can adversely affect their ability to come to the correct cause. Furthermore, I cannot recall a single preliminary report that contained anything like an actual CVR transcript. Those are routinely included in the final report, but not preliminary reports. About the only time you'll see unvalidated information is when there is a suggestion that there is an imminent air safety threat - in which case appropriate emergency inspections are ordered (sometimes even aircraft groundings).

I have a pretty vivid memory: In the aftermath of the Chicago DC-10 crash when the engine ripped off the wing, a couple of days later some department head (I don't remember if he was FAA or NTSB) stood on the podium holding a broken bolt and pronounced that it was the reason the engine came off. Unvetted information that turned out to be complete BS - but resulted in massive outrage that 'the engine was held on by one bolt' - more BS. Fortunately it didn't derail the investigation - and even had a silver lining in that the order bolt inspections lead to the discovery of the actual pylon structural damage that had caused the engine mount to fail. Similarly, after the Columbia Space Shuttle disaster - I watched the clueless head of NASA stand in from of the TV cameras and state as fact that a piece of foam could never have punched a hole in the Columbia wing (obviously never studied that mass*velocity squared thing) - which of course we again know was complete BS.

I've been involved in a few fatal accident investigations - the big one being the Lauda 767, where I was called in early. I was one of the first people to see the FADEC NVM readout that made it painfully obvious that the T/R had deployed at 23,000 ft. - something that we didn't think could happen. We (Boeing) had missed something, and a lot of people had died as a result. It really bothered me (more than once during that investigation, when I got home from work, I just sat down and drank a large glass of Scotch). And not being able to discuss any of it with anyone not involved in the investigation just made it worse. But I knew the rules, understood why there where there, and I followed them.

The article does suggest that the voices have been identified, and that the FO was panicked by the action, and therefore unlikely to have been the one who cut the switches.

The US does have an interest in keeping blame away from Boeing, and are perhaps frustrated by the vagueness of the preliminary report, which was careful to include mention of an irrelevant Boeing advisory. The 'sources close' is standard for US media, and means they're pretty sure of their ground.

That's pure speculation!

There are a number of factors that suggest it wasn't suicide. Until further information is released it's impossible to say

It isn't enough necessarily - we don't know if info has been omitted from the initial report - they won't release info at this stage unless they are 100% confident it is correct.

Please stop this nonsense. There was no problem with the engines until one of the pilots set both fuel control switches to the CUTOFF position. Why is it so hard to understand that the change of position of the switches is the reason there was no thrust anymore? There is not a single report of a switch failure on any of B787 aircraft.

BTW, pondering some of the perhaps slightly ambiguous phrasing in the Preliminary Report, I asked a Hindi-speaking friend to look at the Hindi language version. But it turns out - very much open to correction! - that the Indian AAIB issues its reports only in English (Hindi and English are the two official Indian Govt languages). A clue is that Indian AAIB reports don't have that note you often seen in, eg, French English-language Accident Reports that, in the event of differences, the French language report rules. So, what the AAIB said is what it meant to say.

This is likely to be very close to the final report. The switches moved themselves and all the other nonsensical scenarios being brought up make zero sense and in most cases simply could not happen.
As to not putting out the CVR there is always tremendous outside pressure on an investigation of this scale. Air India is important to the nation. As someone else mentioned when the final report is published it will be old news. Time works for Air India in this case. They appear to finally be making solid progress on a return to financial solvency. The powers to be are not going to jeopardize that turnaround. The answers will come with the final report at a time when it will do far less damage to Air India.

WSJ being leaked to again and they are not even trying to hide the fact that it is US officials doing the leaking as with the leaks in the days before the preliminary report

it\x92s hard to justify this and it does just make the AAIB\x92s job more difficult, would the NTSB appreciate Indian entities leaking to the Indian media before a preliminary and then final report?

im not saying it\x92s correct but it does only fuel the simmering Indian (domestic) audience\x92s views of a US/Boeing \x91coverup\x92

what new details were actually revealed here, it didn\x92t counter the facts laid out by the AAIB prelim at all so it\x92s not like we can claim the AAIB is covering up and the US has to issue counter factuals (as with the China Eastern 737)

I can fully understand and appreciate the leaking. I have been studying the bull!!!! reporting by India media about the cause of this crash. Former senior pilots, some who flew the B787, tell complete utter nonsense about possible technical issues. Like the engines failed and that was the reason to set both switches to cutoff.

It is important to know who asked ' why did you cutoff'. Because it confirms that captain, who had both hands free, set both switches to CUTOFF for no reason.

has the Indian media cited the AAIB as a reference? A lot of people have spouted nonsense on this subject regardless of nationality- the most popular aviation influencers/commentators have changed their stories about 3-4 times already and amplified outright Misinformation

im not sure how that justifies those with privileged information clearly on the US side leaking undermining the official investigation that is being run with international observers from multiple countries and in line with ICAO guidance

I\x92m not saying it is but it gives off more fuel to idea that Boeing has deep sway inside the US elites and institutions

your last paragraph is conjecture, we can speculate but the job of the investigators is to be 100% accurate, it\x92s easy for us to sit on the sidelines and throw out whatever theories we like but their responsibility is much higher

if US entities aren\x92t happy with the tone/substance of the preliminary report their is a mechanism for them to provide there own findings at a later date, this cloak and dagger selective leaking stuff really is uncalled for

Saying so doesn't make it so. There is nothing "simple" about pilot suicide, major depression is a complex condition to begin with and the aviation context adds multiple complicating layers of conflicting motivation. I have stated before that depression and suicide are being displayed irrationally here by a number of people. It's simply not a magic explanation you can just wave at any behavior you don't understand. That's not how that works.

All known cases of pilot suicide have indicators that are not present here. In some cases (like the often mentioned Germanwings incident) those indicators were such strong evidence that the criminal case was open and shut in days or weeks. Those weren't "simple" cases either, but they had the evidence one would expect from a pilot suffering such a complex condition. Nothing of the sort is known about either the Captain or the FO.

Suicide is almost always the last step in a long history of suffering from (mental) illness. Suicidal ideation is what the medical field calls thoughts (ideas about) suicide. It's a comparably common symptom shown in around 5-20% of adults worldwide with strong variation correlating with external factors, such as economic well being, occupation, stress, etc. Assessed globally Pilots, as far as relevant studies are available, seem to fall into the lower bracket of prevalence of suicidal ideation with a lower than expected prevalence when compared to the general population from their respective country of origin down to the rate observed in the general population of economically stable and strong countries.

Cases where pilot suicide is suspected (any case where at least some level of evidence is present but either no or only an officially disputed final assessment exists) also generally follow the same patterns. Attempts at concealment are known to happen, but make up only 10%-30% of completed suicides in the general population. This does include the gray area of potentially successful concealment which would lead to the assumption of an accidental death.

In almost all cases a recurring pattern is also the topic of certainty. In suicidal ideation it is a very common theme that any issues are projected into the future and the uncertainty of those issues generates anxiety. Many survivors of suicide attempts reveal that they considered the certainty of their own death to be preferable over the continuance of uncertainty and the associated anxiety. While we are far from being able to authoritatively call this a definitive mechanism in the psychological conditions related to suicide it is strongly implicated and subject of ongoing research. My personal way of explaining this to someone unfamiliar with depression is that your brain is quite literally poisoning you and generating so much trauma that the idea of ending it becomes preferable. Patients in this stage of major depression show a determination and rationality in their drive towards that goal that is often the primary source of perceived irrationality from the outside. They routinely ignore any and all information that is not relevant to their goal. The means are often chosen with preference of perceived certainty over any other motivation, including harm to others.

Summarizing:
1. Suicide is overwhelmingly the last step in a history of mental illness and almost exclusively presents without that in cases of immediate, significant and obvious trauma.
2. Attempts of concealment are of low probability in a suicide.
3. Methods of suicide are commonly chosen based on perceived certainty of success.

These indicators are all negative for the Air India accident. There is no indication of a prolonged history of mental illness, there is no immediate, significant or obvious trauma. Theorizing an attempt at suicide by either of the pilots requires the assumption of a major attempt at concealment. And most importantly: The method chosen is not following the pattern of maximizing certainty, the probable reason why all confirmed and even all suspected cases of pilot suicide happened in cruise flight.

The theory of suicide is thus, in this particular case, a bad fit.

If we are assuming an (intentionally) concealed medical condition there are much simpler and more likely candidates available. Any type of cardiac issue could lead to a clot and a stroke. A stroke fully explains what happened here. A clot triggered by the acceleration of the takeoff run could very reasonably present as a stroke in the timeframe given here. If the victim belatedly realizes what happened he may develop the wish to stop the situation, which in a stroking brain could absolutely lead to the shortcut of "turning off the engines is done at the end of flight". Or the stroke victim is trying to hold onto something and grabs the switches relatively close to the relaxed hand position after releasing the thrust levers at V1. Other conditions can rapidly present and impact judgement, motor function, or both. If we are willing to attribute the Captains recent decision to retire and be with his father as a potential change in character we might even fall into a number of neurological conditions that may be causal.

But there are even simpler explanations than a concealed medical condition. Maybe one of the pilots had previously finished recurring training for evacuations on the runway and had discussed this with his colleague ahead of the flight. The final memory item for those is turning off the fuel pumps. This kind of Action Slip is well documented. It's not very likely, thus I have no issue believing no one reported observing that type of a slip in a simulator, but it's not like accidents with this level of weirdness are common. There is however a good indicator here fitting the situation of at least one of the pilots: The Captain may have been preoccupied with his wish to retire soon and spending time with his father. While the latter makes absolutely no sense in a suicide it could be part of the causality for an action slip. Also note this post about inadvertent activation of switches despite majorly different modes of activation.

In the end here are three observations based on the preliminary report:
1. Any type of mechanical fault is unlikely and no immediately supporting evidence has been found.
2. A human factor is currently the most likely candidate for the cause of the accident.
3. The type of human factor is not being speculated upon in the preliminary report.

Note that the report specifically states:
No further reference is made to any medical conditions, which is expected as these would fall outside the guidelines for inclusion in a preliminary report.

Attribution of an unclear accident to suicide is contributing to a problematic pattern of stigmatization and increases the likeliness of concealment of (mental) health issues associated with that stigma. In addition it precludes proper analysis of a potential inadvertent mishandling of controls. Both Airbus and Boeing commonly utilize this position and type of guarded switch. Both are sufficiently protected against accidental movement but nothing else. In many smaller aircraft setting the Master Switch to Off would not lead to engine shutdown. There are even reports of what we could consider negative training, by flight instructors demonstrating this fact by turning the Master Switch off in flight. Other commercial aircraft utilize different schemes, Embraer was mentioned right at the beginning of this thread by moosepileit as requiring Throttle Levers at idle for Fuel Cutoff as well as positioning those switches on the overhead panel .

Having just done a full review of this entire thread with regard to human factors I find it a bit sad to note that from the start there were multiple people with backgrounds in accident investigation present that pointed out human error and gave proper reasoning or even corroborating evidence in the form of accident reports. There are also multiple people repeatedly injecting their theory of pilot suicide either without providing any evidence or referring to baseless rumors from media reports. Notably those same people often rejected any other possibility of human error. They also repeatedly make statements of fact that are contradicted or not covered by the preliminary report. Any discussion of mental health seems pointless at this moment in time since there is no actual interest in the topic beyond occasionally going "It's suicide, duh". If anyone is interested in the topic I can once again only recommend taking a look at the Pilot Mental Health Campaign Research Page and other resources presented there.

I think the other worthwhile takeaway from this thread has been stated rather early, with the very applicable nod to a better layout regarding critical functionality that has no reason to be present in close proximity to regularly used flight controls.

Great post. Agree with your reasoning here. I also don't post often, and after this, I think I will return to the quiet life when surfing online forums.