bryangiggsy wrote: » From Sky News Germany's air safety authority has just said 737 MAX 8 and 9 models will be barred from their airspace until 12 June - three months
Damien360 wrote: » Has there ever been a determination of cause from accident authorities in 3 months ? Even a preliminary one ? It's an odd timeframe.
Tenger wrote: » Those nations that issued grounding orders obviously have concerns. Those concerns will need to be addressed by Boeing.
Tenger wrote: » Those nations that issued grounding orders obviously have concerns. Those concerns will need to be addressed by Boeing.https://www.nytimes.com/interactive/2019/03/11/world/boeing-737-max-which-airlines.html Updated with map of all groundings. Only Russian, Kazakh, Canadian and US aircraft still flying. I make that 100 aircraft out of 360+.
Safehands wrote: » Even when this problem is resolved are the paying public ever going to be happy flying in a Max? Over 300 people have died horribly in this model over the past 5 months. That is going to be hard to forget, no matter what assurances are given by Boeing. The DC10 never really recovered its reputation after the bad press it received over the Paris accident. Will the Max recover? I doubt it! It's a pity, because it's a lovely plane.
Bob24 wrote: » Tenger wrote: » Those nations that issued grounding orders obviously have concerns. Those concerns will need to be addressed by Boeing.https://www.nytimes.com/interactive/2019/03/11/world/boeing-737-max-which-airlines.html Updated with map of all groundings. Only Russian, Kazakh, Canadian and US aircraft still flying. I make that 100 aircraft out of 360+. Good link. Basically as of the latest version of the map at the beginning of then article, at this stage the plane is mostly being used within the US and a little bit between the US and a few neighboring countries - and is grounded almost everywhere else. I don’t know if it is the US taking a calculated risk to protect a national corporate giant or other countries being overzealous because it doesn’t impact them too much (possibly a bit of both), but looking at the map it is hard not to think there is a good level of politics involved in decisions to ban or not to.
A pitch augmentation control law (MCAS) was implemented on the 737 MAX to improve aircraft handling characteristics and decrease pitch-up tendency at elevated angles of attack. It was put through flight testing as part of the certification process prior to the airplane entering service. MCAS does not control the airplane in normal flight; it improves the behavior of the airplane in a non-normal part of the operating envelope.
goingnowhere wrote: » That assumes you have valid AOA data...
kippy wrote: » In the Lion Air crash, was the root cause a faulty "sensor" or how the plan handled a perfectly normal part of flight or how the pilots dealt with the plane dealing with a perfectly normal part of flight?
Bob24 wrote: » I am not sure how official all that is and take my understanding with a pinch of salt, but what I gather form the article I read is that a wrong sensor reading would have caused the plane to trigger an automated control system which caused the crash while the pilot was trying to fight it (I also read the pilot could technically have disabled the system when it started to malfunction but either didn’t know how to go it or didn’t have time to do it).
mickdw wrote: » But would they have done something as stupid as building such a safety critical system around a single sensor? What happened to 2 or 3 levels of redundancy in aircraft systems?
Budawanny wrote: » Faulty AOA readings caused the MCAS system to repeatedly send nose down commands to the stabilisation fin at the back assuming that the AOA was approaching stall. The pilots repeatedly fought against this. until there final effort was not enough to affect the MCAS inputs. At least one salient point from this is that I believe the MCAs system was taking input from only one AOA sensor. Logically I would expect dual input and if they disagree, disable the system, or preferentially , three inputs so you can identify which one is right or wrong. It is possible to disable the system, by flipping a couple of switches, but you have to know what the problem is first , considering this was a new unannounced system, its perhaps understandable they didnt. The plane was at low altitude with a risk of terrain impact so they had a lot going on in the cabin also.
Bob24 wrote: » Thanks, although I had the gist of it, that’s a better way to explain it than I did :-) Am I right that these nose down commands are an additional safety measure (when working as intended) which doesn’t exist on all airplanes, and that if working as intended they would only be required in rare scenarios whereby a pilot would be expected to know there is a problem and to be able to address it? Where I am getting at is: if these are only used in rare cases and that a pilot would be able to handle that scenario without the automated commands, would it not make sense to disable this feature until everything is clarified knowing that it has currently probably taken more lives than it might have saved?
U.S. officials wanted to have the recorders sent to the National Transportation Safety Board on grounds that American government experts would provide the most reliable and accurate data downloads, according to the report. The U.S. hadn’t received a final decision as of late Tuesday, according to the Journal.
billie1b wrote: » The Lion Air crash involved the MCAS system, the Ethiopian one nobody knows yet. In the case of the Lion Air Pre-Lim report, not confirmed, but before the crash there was an abnormal reading of a 20 degree difference in the AOA sensors before take-off, there is an optional package that airlines can purchase to inform the flight crew of the readings, a light in the flight deck that illuminates to say there is an abnormality with the sensors and allow the crew to run checks on the problem, Lion Air didn’t pay for the optional package and thus their crew of 610 took off without knowing there was a problem before they even got in the air. In my opinion, these packages should come as standard and not be an optional extra when they are attached/part of such a critical component of the aircraft.
Nijmegen wrote: » In a very odd turn of events, it seems the US is throwing its weight around lobbying the Ethiopians to have the FDRs sent to the NTSB for inspection rather than, as planned by the Ethiopians, to the UK. From the article: I would really question the notion that US government experts would be any more reliable at downloading the data than British ones. Doesn't smell right.
cnocbui wrote: » Apparently the US tried to persuade the Indonesians to hand over the Lion Air recorders to them also but they declined and downloaded the data in-house at their National Transportation Safety Committee (KNKT). The US are collectively so far up themselves it beggars belief.
Roger_007 wrote: » Boeing risks suffering irreparable reputational damage if it appears to gloss over something that it got wrong. The reason why aviation has become so safe is because, over the years, manufacturers have usually cooperated fully in the investigation of accidents and incidents and took responsibility for deficiencies. Aviation safety is not an area where you can play politics and it seems that politics may be at play in decisions being made in the grounding or otherwise of the 737 MAXs. I hope I'm wrong.
murphaph wrote: » Yeah it's concerning not just that Boeing may not be as forthcoming as one might hope but also that the FAA is still not really a neutral safety agency. It has this commercial role to promote aviation that must clash sometimes with their role as regulator. I am much more comfortable with the recorders going to the AAIB.
plodder wrote: » I guess it would be the NTSB rather than the FAA investigating though.
Budawanny wrote: » It is possible to disable the system, by flipping a couple of switches, but you have to know what the problem is first , considering this was a new unannounced system, its perhaps understandable they didnt.
Mebuntu wrote: » Yes, but I'd have thought that MAX pilots would have had a unique interest in the earlier high-profile Lion Air crash (and that aircraft's previous flight incident) and how it came about and would be on high alert after takeoff even without any input from Boeing. I find it difficult to believe that when it happened to them they were "wondering what might be wrong here ".
