It seems that there are "interesting" ways that you could have a lot of wealth, but shield your children from the negative effects. For example, let's say you drove mostly older cars, teaching your kids to maintain and repair them themselves. Or let's say you lived in a huge house, but you don't have a cleaning crew - the family works together to clean the house on Sundays. Everyone fights, no one quits. If you made it your goal, you should be able to decouple "instill a serious work ethic" from "we own assets worth millions or billions"
I'm seeing this "Firefox detected a potential security threat and did not continue to www.hackersalt.com. If you visit this site, attackers could try to steal information like your passwords, emails, or credit card details."
The Hawaii stores were taken over from Daiei (Japanese supermarket chain) and I don't think they've changed that much, still a different animal from the Japanese Donki stores I've been to. In comparison they've opened a couple Daisos in Hawaii recently and the goods are identical to what you find in any Daiso in Japan.
I had a coworker once bring back everyone some decorated chopsticks from Daiso after a trip to Japan. We worked across the street from a Daiso that got the same chopsticks in stock about a week later.
One thing I haven't seen fully explained ( maybe it was but I missed it ). Were these vanes damaged on both of these downed flights? Why didn't all the other 737 MAX 8's crash around the world, Was it something about the flight profile or the weather? Can the plane be flown as-is with a sufficiently conservative flight profile?
The sensor was never designed for what it was used. It was designed to provide input to a visual display for the pilot. The pilot always had a lot of other inputs. The reliability requirements were totally different to what was needed to directly control an airplane in a critical situation.
The software design compounded the problem with some bizare design decisions.
This was a system design failure. High level reliability requirements were not properly communicated to the subsystems. Subsystem failure was not properly analyzed. Human Machine interface considerations were ignored.
Considering the rush job and shortcuts Boeing made for this "feature" a valid consideration by a regulator would be to question their quality system. And that should trigger a systematic approach to reviewing all other requirements and design work going into the 737MAX.
There just aren't that many MAX planes. Only went into production in 2017, around 350 delivered to airlines. The vanes were presumably damaged (either mechanically or electrically) on both downed planes but not others.
> You and other keeps parroting this line, I don't believe it to be true.
You are free to believe anything you want to believe. Of course if you where involved in the 737 Max development and you have inside information to the contrary then I'll accept that.
It's the explanation which best tallies with the official description of the system, the circumstances surrounding its introduction and the certification requirements.
Many aircraft have systems implemented to prevent stalls (see stick pusher); and systems to prevent undamped yawing movements becoming uncontrollable (see yaw damper). And to prevent mach tuck (see mach trim system); and to prevent changes in pitch trim due to speed changes (see Speed trim system).
1. The position and size of the upgraded engines for the 737 MAX caused the plane to tend to pitch upwards, which could cause a stall.
2. Boeing was concerned designed MCAS to automatically push the plane's nose down to prevent stalls
Every single piece of reporting I've seen on the matter refers to MCAS as an anti-stall device.
Pilots of 737 who have talked to reporters refer to it as an anti-stall device.
I have a hard time believing that this information hasn't been fact checked to hell and back yet.
> Every single piece of reporting I've seen on the matter refers to MCAS as an anti-stall device.
Assuming you are a developer, have you ever seen some reporting of something technical in the news? Does it not make you cringe?
> Pilots of 737 who have talked to reporters refer to it as an anti-stall device.
Even Boeing themselves do; so who can blame them. The reason that the certification item exists is to prevent certification of aircraft which demonstrate increasingly lighter control forces as the aircraft approaches a stall. The reason being that it makes it easier for an inattentive pilot to accidentally fly the aircraft into a stall. So if you want to shorten that to anti-stall then I'm fine with that.
What I don't really like is the retoric about how these aircraft would fall out of the sky without MCAS "controlling" the plane. It isn't a closed loop control system implementing PID control to account for some crazy instability in the aircraft.
> Every single piece of reporting I've seen on the matter refers to MCAS as an anti-stall device.
"Anti-stall" has become a catchphrase wrt the 737 MAX. I wish everyone would stop using it, but the horse has left the barn it seems.
MCAS was cooked up to maintain the handling characteristics required by the FAA certification specifications.
Other commenters in other threads have explained why consistent response curves are vital in operating an aircraft, so I won't take on the why of the regulation other than to say it's well founded and some smart systems/human factors engineers have elucidated on this in earlier threads. Otherwise, wouldn't it have been easiest of all for Boeing to beg "let us have the airplane respond this way; all planes are different, right?" And even if the FAA allowed that, it'd force a new type rating, I suspect; the very thing they so badly wanted to avoid.
The standard (see below) requires stick resistance to increase as the critical (stall) angle of attack is approached. The MAX violated that requirement due to the aerodynamics of the new engine cowls. (So: why didn't they mess with the cowls? I suspect that wasn't possible without impacting efficiency, which is a key selling point of the MAX.)
Back to the spec: as noted, it exists to provide a consistent response curve to the pilot compliant with the regulation.
As borne out by these accidents, MCAS is Boeing's (quick & dirty) implementation of "artificial feel" to meet the spec. Big, transport planes with hydraulic flight controls have had artificial feel for many years to provide a consistent and properly scaled input response (not too heavy, not too light, etc.)
As far as the FAA specification in question, the critical section is in CFR 14 §25 Subpart B—Flight ¹, notably the sections on Controllability & Maneuverability and Stability. In these sections 'stick force' appears sixteen times; 'stick force curve' appears six times.
It's "stick force curve" that MCAS was created to tweak. There's no mention of "reduce the critical angle" or "change the stall onset speed" or anything about the aircraft performance. It's about how the plane handles in a particular part of the flight envelope².
> Every single piece of reporting I've seen on the matter refers to MCAS as an anti-stall device.
Because it was printed repeatedly doesn't make it true (see, Gell-Mann amnesia effect³).
²–I'm surprised that MCAS reacts fast enough to count as artifical feel. Electric trim doesn't move all that fast, AFAIK. Still an open question in my mind.
The 737 Max does fly differently, the MCAS and AoA checks to offset the engine "pitch up" due to more powerful engines was to get around a regulation/certification [1].
> The LEAP engine nacelles are larger and had to be mounted slightly higher and further forward from the previous NG CFM56-7 engines to give the necessary ground clearance. This new location and larger size of nacelle cause the vortex flow off the nacelle body to produce lift at high AoA. As the nacelle is ahead of the C of G, this lift causes a slight pitch-up effect (ie a reducing stick force) which could lead the pilot to inadvertently pull the yoke further aft than intended bringing the aircraft closer towards the stall. This abnormal nose-up pitching is not allowable under 14CFR §25.203(a) "Stall characteristics". Several aerodynamic solutions were introduced such as revising the leading edge stall strip and modifying the leading edge vortilons but they were insufficient to pass regulation. MCAS was therefore introduced to give an automatic nose down stabilizer input during elevated AoA when flaps are up.
The regulation that they had to make to fit within the 14CFR §25.203(a) regulation/rule was first tried by physical designs but ultimately settled on a sensor/software solution that constantly polls every 9 seconds to check the nose pitch/attitude and adjust, if it goes to0 far MCAS is triggered and pulls the nose down. Since there was a faulty sensor, this caused the nose dive catastrophic failures.
The 14CFR §25.203(a) regulation (a) is [2]:
>It must be possible to produce and to correct roll and yaw by unreversed use of the aileron and rudder controls, up to the time the airplane is stalled. No abnormal nose-up pitching may occur. The longitudinal control force must be positive up to and throughout the stall. In addition, it must be possible to promptly prevent stalling and to recover from a stall by normal use of the controls.
Since the change had to do with "No abnormal nose-up pitching may occur" in that rule, then the plane definitely flies differently as the cause of the MCAS and sensor flow is to constantly check for a nose pitch up that it corrects, if too far, enable MCAS to bring the nose down. This plane flies differently definitely and a bit opposite in that other planes will pitch down, it pitches up due to engine power of the larger more fuel efficient LEAP engines.
Ultimately the root of the problem was cost cutting which led to retro-fitting the 737NG to the 737 Max 7-10 to fit within cost/training/testing/regulations and in the end that was the problem that caused the end result of a software/sensor single point of failure which has squandered trust in Boeing engineering, management and safety as well as the 737 brand. Most people don't know the 737 Max is essentially an entire new plane. How the FAA let Boeing get away with this will be a focus as time goes on.
As a software engineer, the 737 Max looks like a legacy system hack that they tried to version 2 with it rather than make a new plane and incur all the training/testing/certifications of a new plane.
Boeing other planes don't have these issues, the 767 is has only had a couple issues beyond terrorism and those were related to pilots and fuel [3]. Two crashes of two new Boeing 737 Maxs within months of release and service is not a good trust enabling product.
I'm unconvinced that a software routine (MCAS) that can be (indirectly) disabled, and pilots are instructed to disable in the case of MCAS upset, is an acceptable work around for any portion of FAR 25 certification.
I think it's more likely that MCAS was intended to avoid a new type certificate for the MAX, thereby triggering FAR 61.31(a) requiring that the pilot be type rated.
Either way we have a problem here, as I see it. The aircraft flight manual and emergency AD 2018-23-51 specifically recommend a procedure that instantly makes the airplane not airworthy, or renders the pilot flying an airplane with behavior he's not really type rated for. This seems highly problematic, and I'm not able to account for it.
As far as I understand, the older 737 models also exhibit a nose-up pitching behavior in high-thrust/low-speed situations, to the point that stall recovery procedure explicitly specifies that the nose has to come down first, before thrust is increased. And maximum thrust may not be used, only max continuous thrust (or something similar) because otherwise the pitch moment from the engines may overwhelm elevator control.
Good question, apparently on the 737 Max this is more pronounced with the larger/forward LEAP engines.
This was enough of a problem that it constantly has to be checked and MCAS has to trigger if it is off by too much.
Most planes have a nose down pitch over time but the 737 is smaller/lighter so maybe the engines have always affected flying.
With the 737 Max and new LEAP engines, here it was enough for Boeing to make a system for it, they didn't make it just for extra, it was a cost cutting measure already.
> stall recovery procedure explicitly specifies that the nose has to come down first, before thrust is increased
Pulling the nose down is probably standard on any stall recovery because the nose up exacerbates conditions for a stall.
The problem wasn't really with the nose pitch up, but the nose pitch up created the need for nose up detection/monitoring and an MCAS in case of issues.
The major problem is that MCAS relies on a single sensor and a single point of failure, which can result in the MCAS constantly pitching the nose down if it is bad data or a broken/incorrect AoA sensor.
The root cause of this major problem is the cost cutting retro-fitting that Boeing did and their reliance on a single point of failure that can trigger a catastrophic nose dive.
This is one of those cases that the fix to keep the 737 flying the same as previous versions, without pilot knowledge of the MCAS initially, caused more damage than just the pitch up might do.
I don't think you understand the market the A32x and the 737 are in. They are planes flown by carriers who want to keep costs low. The MAX was designed the way it was because the airlines wanted more of the same with minimal retraining and support retooling. Boeing had originally proposed and may still pursue a carbon-fiber redesign of the 737 incorporating more of the lessons learned from the 787, but for now the airlines wanted and got a progressive improvement on the 737.
The MCAS system was designed as a response to FAA requirements and directives based on a concern about performance at the edge of the flight envelope. Since as we see it now (the public does not have enough information to conclude on how well the design process went except in the result) it was designed poorly and improvements are being made.
Once those improvements are made I expect the MAX to be, at that point a safer aircraft than the 737 NG. Its unfortunate that so many people had to die before the issue was identified, maybe congress should provide more funding for aviation safety enforcement and research at the FAA, NTSB and NASA.
The AoA sensor that MCAS uses, as well as the nose pitch monitoring adjustment due to the larger more powerful LEAP engines that causes a pitch up on the nose, is external and in the front [1][2].
> Stall sensors are common, but the MAX is the only 737 to have a blade-like sensor on the exterior of the plane that can automatically pitch the plane down when it detects stall conditions -- without input any input from the crew [2]
Not only is it susceptible to birds but it could be sabotaged as well from the location of it, if I were investigating it I'd check into maintenance/storage/possible sabotage just in case.
Since the nose pitch monitoring system and MCAS use the AoA single sensor it is a single point of failure, it also seems like a security issue.
About the single sensor and single point of failure[2]:
> Boeing's 737 MAX, the model being flown by Indonesia's Lion Air that crashed last October killing all 189 on board, had been criticized for relying on a single sensor to detect the aircraft's angle of attack, according to today's Wall Street Journal. A preliminary investigation by Indonesia's National Transportation Safety Committee (NTSC) blamed the stall prevention system (known as Maneuvering Characteristics Augmentation System, or MCAS) which relied on a the single sensor that provided erroneous data, causing the MCAS to misfire, leading to a series of events that put the plane into a nosedive.
> After the October crash, Boeing began updating the plane's software so multiple sensors would provide data to the stall prevention system, the company said in a statement on Monday.
About the external AoA sensor [1][2]:
> The 737 MAX with its larger engines mounted even more forward needed a separate sensor to sense stall, the nose up attitude of a plane that turns off aerodynamic lift over the wings. Stall sensors are common, but the MAX is the only 737 to have a blade-like sensor on the exterior of the plane that can automatically pitch the plane down when it detects stall conditions -- without input any input from the crew --according to Seattle Times veteran aerospace reporter, Dominic Gates, who is close to Renton, Washington where the 737 MAX is assembled.
> According to the preliminary report from Indonesia's NTSC and in a Boeing service bulletin, Lion Air flight 610 was providing erroneous data from a angle of attack (AOA) sensor. It appears the crew may have been fighting against: bad sensor data, a multitude of warnings and an automatic flight control system that seemed to be malfunctioning by automatically pushing the nose of the plane down repeatedly during the 11-minute flight. Ground control was contacted numerous times by the crew, who were repeatedly requesting permission to return to the airport.
That is really an interesting point on sabotage. Will these planes be cleared to take off without the sensor functioning though? I think the sensors failed after take off in these crash cases.
It's generally difficult to test these sensors before takeoff, it's basically a little blade or wing which measures the relative wind over the aircraft. Without forward speed it has nothing to measure.
On the lion air the sensor was non-operable from the start of the flight; so yes on both flights the AoA sensor was in a non-flightworthy condition.
One point of clarification: on the 737 and most other airplanes the airspeed is unreliable if the AoA sensor becomes damaged. This occurred on both the ET302 and the lion air flight. In such a state, it is up to the pilot to place the plane in safe flying state that does not depend on access to the airspeed. The pilot should by memory, ideally, set the thrust and nose up attitude of the plane along with other control surfaces. Failure to do this is what indirectly caused the AF447 disaster and it seems the the crew didn't execute this procedure on the ET302 flight. At the very least, attempting to engage the autopilot and disengaging flaps were contrary to standard procedure. Not executing this procedure dramatically increases the workload on the pilot and increases the risk that either airspeed wall outside of the safe operating range of the aircraft or the pilot will have to take drastic action to maintain airspeed in a safe range. Both are dangerous and even an experienced pilot can fail to take appropriate action especially in an emergency with the flight crew attending to other anomalies.
With that caveat stated, there is nothing inherently unsafe about flying with the combination of unreliable airspeed and an uncommanded MCAS activation in theory. The previous flight of the lion air flight was able to counteract 20+ instances of MCAS activation by simply trimming the aircraft using manual trim before they tried disengaging electrical power to the stabilizer motors. After disengaging trim the pilots felt comfortable continuing the flight and adjusting trim using the manual cockpit trim wheels. With all that being said, no aviation regulator would certify a plane that couldn't fly safely with an unreliable airspeed and manual trim turned off.
I think the question about why the 737 MAX's haven't crashed more is two fold. First, a birdstrike that takes out an AoA sensor is very rare. In that sense, Boeing got very unlucky in that they had a birdstrike that knocked out the specific AoA sensor tied to MCAS a month before they planned on rolling out the software update. Additionally, flight sensors are usually maintained very well as they are a critical item. You would never expect standard maintenance procedure not to fix an unreliable airspeed. When it has happened before though, the outcome can be tragic just as it was on the lion air flights regardless of any issues with MCAS.
If you have a single source of income and don't mind over-withholding (and getting a refund come tax time), yes.
If you want to reduce the amount you're withholding (so you pay less during the year, and receive less of a refund), you have to claim allowances. And the way those connect to the amount actually withheld isn't entirely straightforward (it's the tables starting on Page 48 at [1]).
And then it gets way more complicated if you have multiple sources of income, because the withholding calculations don't work in that case (underestimates your withholding, and you end up owing the IRS money at the end of the year).
I haven't seen the new form and can't say whether or not it's actually any better, but it can't be much worse; the current W-4 is one of those forms that looks simple ("just" two numbers to punch in) but turns out to be a fair bit more complicated.
Under penalties of perjury, I declare that I have examined this certificate and, to the best of my knowledge and belief, it is true, correct, and complete.
Where you must have at least an allowance of 1, for yourself. And why would you want fewer allowances? That results in more withholding, which is an interest free loan to the government.
You can claim a withholding exemption only if last year's tax liability was zero, and if you expect this year's tax liability will be zero.
Because you have investment income that is otherwise untaxed. I know someone who put 0 and still owed money at the end of the year, but didn't have to make quarterly payments. She had enough investment income to owe, but not enough to hit penalty levels of owing.
> Where you must have at least an allowance of 1, for yourself. And why would you want fewer allowances? That results in more withholding, which is an interest free loan to the government.
If you have other income that's not easy to setup withholding on (such as stock related income, a home sale, or rental income), it can be useful to have more withholding from employment income. A benefit is that you are allowed to pretend withholding is evenly distributed over the year, even if it's not, or if it's more beneficial, you can use the actual timeline for withholding, although that takes a lot more effort.
That applies to your personal information, and your answer to Question 7 (if you are exempt from withholding entirely), which is the only affirmative statements you make on the form.
Lines 5 and 6 are choices the taxpayer makes based on their expected level of withholding. The worksheet is not submitted, and not completed under penalty of perjury.
You can absolutely over-withhold and just put zero. The IRS has zero issue with that whatsoever.
One reason I've used 0 in the past is to allow for multiple income sources (e.g., an employee at one company and a self-employed side project). The worksheet allows for negative offsets to be added into the final deduction count recorded. It avoids the need to deal with quarterlies if the withholding amounts are close enough.
Not sure what "it" is in this scenario, but if you owe too much in April, there's a penalty and you may need to pre-pay the following years' taxes; and if you are refunded too much, you have granted the government a large, zero-interest loan. I also believe that, however unlikely, lying on your W-4 is technically punishable by fines/jail/whatever.
is Zero an option anymore, or is this entire article about how they are making the form more accurate instead of just picking a nearby number out of a hat?
With wireless 5G coming, people will have a real alternative to something that uses a physical line to the house. Brace yourselves, competition is coming.
