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rob smith Send message Joined: 7 Mar 03 Posts: 22200 Credit: 416,307,556 RAC: 380 |
That all depends on what is meant by "switched MCAS off". There are two ways it can be "turned off" - if the pilot takes over control by moving the control column more than a certain amount and for more than certain amount, or uses the control column trim toggle then MCAS stops acting for a time. - if the pilot turns the two switches off then MCAS is isolated, and the servos between the trim wheels and the tail plane are cut out. Obviously the latter is "properly turning it off", while the former is a "hold on a moment" , what is not clear in any of the news reports is exactly what mechanism the pilots used. But given that there didn't appear to be anything in their training or the checklists about the full action of the two isolation switches I would suspect they went for the trim toggle approach, and repeated it a few times, until the plane was heading to buy some real estate of its own. Bob Smith Member of Seti PIPPS (Pluto is a Planet Protest Society) Somewhere in the (un)known Universe? |
W-K 666 Send message Joined: 18 May 99 Posts: 19060 Credit: 40,757,560 RAC: 67 |
Below is the relevant section taken from the WaPo Additional software problem detected in Boeing 737 Max flight control system, officials say The preliminary report, which stops short of determining the cause of the crash, chronicles the chaotic last moments in the cockpit before the crash. |
Grant (SSSF) Send message Joined: 19 Aug 99 Posts: 13736 Credit: 208,696,464 RAC: 304 |
After the Indonesia crash, Boeing issued a bulletin outlining how to disable MCAS in case of a malfunction, and Thursday’s preliminary report indicated that the EthioÂpian pilots followed that procedure. It would be nice to see the report in order to understand how they came to that determination, as the bulletin states clearly- ...ensuring that the STAB TRIM CUTOUT switches are set to CUTOUT and stay in the CUTOUT position for the remainder of the flight It has been my experience that circuit breakers, once tripped or manually shut off, don't re-close themselves unless they are that specific type of breaker. Auto recloser breakers are used in high voltage distribution networks and they have a set number of re-tries before they stay tripped, i'm not aware of any such breakers for low voltage systems (which doesn't men they don't exist). Even so, I can't image such a breaker being used in this case. And for something to continue to function once it's official source of power has been cut would be highly unlikely. Grant Darwin NT |
W-K 666 Send message Joined: 18 May 99 Posts: 19060 Credit: 40,757,560 RAC: 67 |
Hmm...will it stop buses & trucks from hitting bridges? My car, new last year has the speed recognition camera (2 in the fig.) and shows the speed limit on the dashboard plus there are bleeps if you exceed by 10%. But it has a few limitations, you have to pass a speed limit sign, which if you live in a town or city, you might not do for several miles, and sometimes it goes off for no apparent reason, usually after you have had to stop before turning right (UK), probably does the same when turning left in US or remainder of Europe. There are also sensors that warn of accident up to applying brakes full on if it detects crash is inevitable. |
Richard Haselgrove Send message Joined: 4 Jul 99 Posts: 14650 Credit: 200,643,578 RAC: 874 |
... you have to pass a speed limit sign, ...I'm very worried about systems which rely on a single observation to register a change of state, which presumably remains in force until the next observation. You could get out of synch in either direction - either missing the speed reduction on entering a hazardous area, or remaining at restricted speed after you've left the restricted zone. There are plenty of reasons why a speed limit sign could be unreadable - dirt, mis-alignment, vegetation, parked vehicles... My 2017 car doesn't have cameras, but has a limited amount of speed data associated with the SatNav maps: on major highways, the current limit is displayed constantly for me to refer to if needed. It isn't hooked up to the driving controls, it's sometimes out of date, and it doesn't know about temporary restrictions, but the concept of referring to an absolute location seems more robust than "blink and you've missed it". |
zoom3+1=4 Send message Joined: 30 Nov 03 Posts: 65745 Credit: 55,293,173 RAC: 49 |
My 1999 doesn't have any camera, though it could be added using some aftermarket tech, right now it's a moot point since I really don't want one. I discovered that the mechanic who is working on My car only works there 3 days a week. Right now the flywheel needs to be replaced and so the transmission has to be dropped to do the swap from the old engine to the "new" engine. It's been 2 months since I drove My car and about a month since the car started to be worked on, they said after this they don't want to do this again, it takes too long. All I can do now is wait, they said they'd call when it's done. Out here where I live at has no public transportation, the only bus route is between the 15 and 40 fwys, nothing to the south of the 40 and nothing to north of the 15, lovely, not even bus stop signs like in Barstow or bus stop shelters. The T1 Trust, PRR T1 Class 4-4-4-4 #5550, 1 of America's First HST's |
Grant (SSSF) Send message Joined: 19 Aug 99 Posts: 13736 Credit: 208,696,464 RAC: 304 |
There are plenty of reasons why a speed limit sign could be unreadable - dirt, mis-alignment, vegetation, parked vehicles... Bullet holes. Here in more remote areas idiots like to use road signs for target practice. Grant Darwin NT |
Grant (SSSF) Send message Joined: 19 Aug 99 Posts: 13736 Credit: 208,696,464 RAC: 304 |
It would be nice to see the report in order to understand how they came to that determination, Here is a excerpt from the preliminary report, and a link to the report is at the bottom of the excerpt. At 08:40:35, the First-Officer called out "stab trim cut-out" two times. Captain agreed and First-Officer confirmed stab trim cut-out. Further excerpts relating to trim- From 08:40:42 to 08:43:11 (about two and a half minutes), the stabilizer position gradually moved in the AND direction from 2.3 units to 2.1 units. During this time, aft force was applied to the control columns which remained aft of neutral position. Trim is set by adjusting the position of the horizontal stabiliser, positioned by a single electric motor and controlled by stab trim switches on the control wheel or the auto pilot. There is also a Mach trim system that takes effect above Mach .615 by controlling the Elevators with respect to the stabiliser as speed increases. Pitch is controlled by the Elevators which are positioned by the pilots control columns. So far the indications are that the Lion air crash was a result of the MCAS system, and the pilots not disabling it. But whatever caused this accident, it wasn't the MCAS system. However the commonalities between the 2 accidents are erroneous inputs to the flight computer- AoA (Angle of Attack), IAS (Indicated Airspeed) and ALT (altitude) values- resulting in incorrect trim settings. Grant Darwin NT |
Richard Haselgrove Send message Joined: 4 Jul 99 Posts: 14650 Credit: 200,643,578 RAC: 874 |
LOL. Fortunately we don't have those. But we do have street-sign clutter. There are two speed-limit commencement signs in this Google streetview image: see if you can tell me where they are.There are plenty of reasons why a speed limit sign could be unreadable - dirt, mis-alignment, vegetation, parked vehicles...Bullet holes. |
Grant (SSSF) Send message Joined: 19 Aug 99 Posts: 13736 Credit: 208,696,464 RAC: 304 |
There are two speed-limit commencement signs in this Google streetview image: see if you can tell me where they are. Maybe with a higher resolution image? I can see street signs on the far RH side of the bridge, and on the far left is a small white sign (but can't see more than that). A sign (i'm guessing a stop sign?) on the far boom gate, and below that either a white part of the boom or another sign. And the lights at each end of the bridge (speed painted on them that takes effect only when lights flashing?) Grant Darwin NT |
moomin Send message Joined: 21 Oct 17 Posts: 6204 Credit: 38,420 RAC: 0 |
But we do have street-sign clutter. There are two speed-limit commencement signs in this Google streetview image: see if you can tell me where they are.Morton Swing Bridge perhaps?. Carries the road from Crossflatts to East Morton over the Leeds and Liverpool Canal. |
Richard Haselgrove Send message Joined: 4 Jul 99 Posts: 14650 Credit: 200,643,578 RAC: 874 |
Yup. That's the location - on my outward route to the shops, and points south and east. Here's the next street view image: The left-hand speed limit sign was completely hidden by the warning-light mounting panel in the first image: the right-hand limit sign was beside the raised barrier. Both carry extra (non-standard) warnings that you are about to drive past a school entrance. |
Grant (SSSF) Send message Joined: 19 Aug 99 Posts: 13736 Credit: 208,696,464 RAC: 304 |
Try your luck here with a parking sign quiz. I didn't even make 50%- luckily we've got nothing even approaching these made for confusion parking zones. If I ever came across an area with parking signs like those, i'd just treat it as a no parking area & go elsewhere. Grant Darwin NT |
Wiggo Send message Joined: 24 Jan 00 Posts: 34744 Credit: 261,360,520 RAC: 489 |
Try your luck here with a parking sign quiz.As soon as I saw the 1st pic I knew that they we're in the Sydney CBD area. LOL Cheers. |
moomin Send message Joined: 21 Oct 17 Posts: 6204 Credit: 38,420 RAC: 0 |
Yup. That's the location - on my outward route to the shops, and points south and east.LOL:) I love the sign on the road. "Keep Clear". Doesn't it snow sometimes in the North West England? Btw. There was an English pop-rock band here on tour in Sweden that was killed in a driving accident at Södertälje Bridge. Lots of signs that warn you that the bridge is open sometimes... https://sverigesradio.se/sida/artikel.aspx?programid=2054&artikel=6368161 |
W-K 666 Send message Joined: 18 May 99 Posts: 19060 Credit: 40,757,560 RAC: 67 |
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W-K 666 Send message Joined: 18 May 99 Posts: 19060 Credit: 40,757,560 RAC: 67 |
This might be the best idea, if it works youtube - Driver Alcohol Detection System for Safety (DADSS) |
Dr Who Fan Send message Joined: 8 Jan 01 Posts: 3213 Credit: 715,342 RAC: 4 |
ONLY IN FLORIDA.... Three Naked Women Stand Outside Rest Stop To 'Air Dry,' Trooper Shows Up, Then Things Get Really Out Of Control What started off with three women's poor decision to "air dry" after taking a shower at a rest stop quickly escalated into a multi-phase car chase, threats against a trooper with a baseball bat, an attempt to run over an officer, all three women getting tased, and drug and alcohol charges. |
Gary Charpentier Send message Joined: 25 Dec 00 Posts: 30649 Credit: 53,134,872 RAC: 32 |
https://www.bbc.com/news/world-asia-47926714 Three people have died in a plane crash in Nepal, at what is regarded as one of the world's most dangerous airports. Just looking at the photo, it looks like the wing flaps are at zero. Not normally the recommended setting for high altitude short field operations. |
moomin Send message Joined: 21 Oct 17 Posts: 6204 Credit: 38,420 RAC: 0 |
Wing flaps are at zero? Does it matter when the pilot didn't stay on the runway? CCTV Footage : Summit Air 9N-AMH Crash in Lukla Airport https://www.youtube.com/watch?v=nYwqfNqy9GU |
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