Originally Posted by gulliBell
(Post 10302720)
is a maintenance assessment flight required to actually check that the fault has been fixed?
|
So just to clarify regarding the last few posts
The STS reads from alternate FCC on alternate flights. Reset by the landing gear squat switch. So on the previous flight which retained controlability during an entire night flight from Bali to Jakarta despite UAS on Captain side was followed by a flight which lost control in day VMC during a period of UAS on Captain side. Hmmm, food for thought |
https://www.abc.net.au/news/2018-11-...ights/10467826
Lion Air jet had problem with airspeed indicator on last four flights, Indonesia officials sayUpdated about 4 hours agoTue 6 Nov 2018, 4:01amRelated Story: All Boeing 737 MAX 8 planes in Indonesia will be inspected after crash Related Story: Who owns Lion Air and what do we know about its safety record? Related Story: Nothing will change despite the latest Indonesian air tragedy Related Story: Crashed plane was brand new, but had 'technical issue' on previous flight Key points:
Committee head Soerjanto Tjahjono and investigator Nurcahyo Utomo told a news conference that the problem was similar on each of the four flights, including the one on October 29 that killed all 189 people on board. The stunning revelation came after angry relatives confronted the airline's co-founder at a meeting organised by Indonesian officials. At the meeting, Mr Soerjanto said information downloaded from the flight data recorder was consistent with reports the plane's speed and altitude were erratic. Mr Soerjanto told reporters the safety committee was asking Boeing and air safety authorities in the United States what action to take to prevent similar problems on this type of plane around the world. "We are formulating, with [the National Transportation Safety Board in the US] and Boeing, detailed inspections regarding the airspeed indicator," he said. It was not immediately clear whether the reported problem stemmed from a mechanical or maintenance issue, nor whether US authorities would order any checks. "Whether the trouble came from its indicator, its measuring device or sensor, or a problem with its computer — this is what we do not know yet," Mr Nurcahyo said. "We don't know yet where the problem lies, what repair has been done, what their reference books are, what components have been removed. "These are the things we are trying to find out: what was the damage and how it was fixed." https://www.abc.net.au/news/image/10...x2-700x467.jpg Photo: A family member cries at the funeral of Jannatun Cintya Dewi, a passenger of the crashed Lion Air flight. (Reuters: Sigit Pamungkas) Many families face an agonising wait for missing relatives to be identified. Police medical experts have received nearly 140 body bags of human remains and have identified 14 victims. Relatives questioned why the plane had been cleared to fly after suffering problems on its Bali to Jakarta flight on October 28 that included a rapid descent after take-off that terrified passengers. "Lion Air said the problem was fixed, is it true the problem was cleared?" said Bambang Sukandar, whose son was on the flight. "If not, technicians in charge must be responsible." Another man, who identified himself as the father of passenger Shandy Johan Ramadhan, a prosecutor in a district on the island where the flight was headed, said Lion Air had "failed" the families of victims."Since the time of the crisis, I was never contacted by Lion Air. We lost our child, but there was no empathy that Lion Air showed to us," he said. After the meeting with passengers' relatives, Mr Rusdi left in a hurry, avoiding questions from reporters. Safety experts have said it is too early to determine the cause of the crash of the flight. Authorities have yet to recover the jet's cockpit voice recorder from the sea floor, just north-east of Jakarta, where the plane crashed 13 minutes into its flight. Boeing did not immediately respond to a request for comment. The US manufacturer has delivered 219 of the 737 MAX jets to airlines around the world. The Lion Air crash was the first involving this type of plane, which was only introduced into service last year. AP/Reuters |
There are Memory Items for Airspeed Unreliable, they are simple and result in a stable aircraft. There are Memory Items for Runaway Stabilizer for when “Uncommanded stabilizer trim movement occurs continuously”, they are also simple and result in a stable aircraft. For the crowd assuming that the STS somehow caused this thing to go in, the Memory Item for Runaway Stabilizer SHOULD have that covered.... Both defects are honestly not that hard to deal with. I’m very interested to see the DFDR data, but in the meantime it pays to remember, “We don’t rise to the level of our expectations, we fall to the level of our training” |
Why do you ask?
I keep wondering about the flight deck asking atc for their speed, when it should be available on the PFD. (I know, UAS, but why think ATC would know any more than you?) *Unless* something took out the PFD - maybe (and I apologize for even thinking it) the lesson of QZ8501 wasn't learned, and actions on the flight deck made a manageable situation much worse. I get the impression here that as long as the structure remains intact and one engine still turns, a 737 can still get you home, but panic can turn a wise man into a fool.
|
..I can only think of 3 conditions, where a modern jetliner would end up in a high energy descend (provided all flight controls are working normally)..
..Emergency descend, spiral, and out of trim.. ..This flight ended similar to the FlyDubai one..Investigators will find out what happened..Meanwhile, Fly safe B-757 |
Originally Posted by Switchbait
(Post 10302769)
There are Memory Items for Airspeed Unreliable, they are simple and result in a stable aircraft. VFR conditions, daytime, what is the problem of flying level even when your airspeed indicators show absurd numbers. Fix thrust and maintain selected pitch, and you can even look out the windows ... This accident shapes up to be one of the worst example of pilot's dereliction of duty ... unless something hit this aircraft or there was a bomb, or his wing fell off, etc. |
This link was posted by @Centaurus on one of the Pacific forums.
Perhaps more than any dispassionate report this transcript of the CVR from AuroPeru 603 provides particularly useful insight into how erroneous instrument readings can cause serious havoc in the cockpit, despite thousands of hours of experience. Spoiler: this is a sad and scary read, and it doesn't end well. I make no personal comment on similarities to the flight under discussion, but others have commented here on such things; this is it from the horses mouth :( FP. |
Originally Posted by tartare
(Post 10302839)
... Under VFR - Power, plus attitude equals performance? No matter what the panel is telling you - if the top of the panel is roughly lined up with the horizon, and the thrust levers are at a certain setting, you'll keep flying? ...
The question now appears to be a Human Factors one: Why are crews not recognising Unreliable Airspeed events and applying the correct recovery procedures? |
: Why are crews not recognising Unreliable Airspeed events and applying the correct recovery procedures? |
I’m curious what you all read this tea leaf in Ben Otto’s latest WSJ story: But investigators are now focusing on reasons for a subsequent abrupt altitude drop, these people said, followed by the fatal dive. Operation of another flight-control system, called the angle of attack indicator, also is bound to be examined by the probe, according to safety experts. Such devices are critical in telling aviators how high or low an aircraft’s nose is pointing. Angle of attack sensors operate independently from airspeed sensors. |
350 knots at 5000 feet seems indicate that the actual speed was not known by the pilots.
Maybe mining all public domain flight data might inform some useful airline statistics. The data of all four previous flights for this aircraft should indicate the UAS events as described by the investigators. -comments from armchair- |
Originally Posted by Cool Guys
(Post 10301808)
Could we have a similar situation to Air Asia 8501; ie inflight fault finding gone awry, a CB pulled at an inappropriate time?
|
Originally Posted by First_Principal
(Post 10302863)
How is this possible? Can the tape or covers on the pitots stretch enough to compress the air in the pitot to give accurate and consistent speed readings at ground level? That seems very unlikely. |
Originally Posted by double_barrel
(Post 10302894)
What am I missing here? These guys called V1 and V2 on the take-off run. Similarly with the infamous Brisbane take-off with pitot covers on.
How is this possible? Can the tape or covers on the pitots stretch enough to compress the air in the pitot to give accurate and consistent speed readings at ground level? That seems very unlikely. With MAS in Brisbane with the pitot tubes covered, both pilots observed red flags on their IAS displays. So how could they call V1 &V2? The interim ATSB report gives a clue: When the Captain called the 100 knot IAS check, the groundspeed was 100kts. |
Originally Posted by InfrequentFlier511
(Post 10302816)
I keep wondering about the flight deck asking atc for their speed, when it should be available on the PFD. (I know, UAS, but why think ATC would know any more than you?)
To clear up any confusion, it now seems that ATC are unlikely to have had the necessary equipment (specifically EHS) to see JT610's IAS. And even if they did, it wouldn't necessarily have been any more reliable than what the crew's ASI(s) were displaying. Re groundspeed, ATC would have access to that (probably both the GPS-derived GS being sent by ADS-B and a less accurate PSR-derived GS). Having said that, the crew would have also have had groundspeed in front of them, on both the PFD and ND, again derived from GPS and therefore not subject to any UAS issues. |
I really don't understand what is so tricky about maintaining attitude by reference to PFD'S ADI when flying an airliner; even UAS checklists are telling us to do so.
[/QUOTE]..You will after you get more experience..Sounds like you haven´t seen the s**t hit the fan yet.. Fly safe, B757 |
There were many contributing factors in break-up of AirAsia 8501, not least language confusion between Indonesian Captain and French FO. Towards end of CV recording Captain tells FO to “Pull Down, Pull Down”: meaning push! But FO kept pulling back on side stick.Perhaps there was similar language confusion between Indian Captain and Indonesian FO on this Lionair flight. Only the CVR can tell.
|
Originally Posted by B-757
(Post 10303037)
IYou will after you get more experience..Sounds like you haven´t seen the s**t hit the fan yet..
Incidentally, the s***s that hit my fans (and props) so far were up to the point of impact contained in the guts of gulls, magpies, swallows and similar. |
French Captain and Indonesian FO The other way round.. |
All times are GMT. The time now is 04:01. |
Copyright © 2024 MH Sub I, LLC dba Internet Brands. All rights reserved. Use of this site indicates your consent to the Terms of Use.