Did the ALMC deliver letters to every single address in the United States? I don't think they did. They weren't trying to "compete" with the USPS so much as skim off the profitable routes.
The USPS does not deliver to every address in the US.
I don’t know what specifically causes the USPS to deliver to a specific area, but there are entire incorporated cities, some with reasonably large population and density, that don’t receive mail at all except to the local post office. Even UPS and FedEx’s low-cost all-but-the-last-mile services regularly lose packages because they hand them off to the USPS.
They were not even trying to do that, Lysander formed the company with the expressed purpose that the government would sue him. he wanted to get the monopoly protection law for the USPS ruled unconstitutional
Let's say you start a power company in the same area as I, a public power utility.
The board of utilities says that as a regulated monopoly I have to provide power to every parcel within the regulated area.
I charge more than the average cost+ rate so that, on the whole, the denser areas that require less infrastructure can subsidize the less dense rural areas where individuals may require kilometers of dedicated transmission line to service their location.
But you come along and charge less (or give power away), but you only do so in areas where it is either profitable or minimally loss-making.
>but Spooner dropped his rates even lower -- delivering many letters for free.
And you don't do this to run a competing enterprise, but to make a socio-economic/political point.
So all of my customers in the limited areas that you serve, naturally, switch to you.
But the areas you choose to serve, the densely-populated ones, are the areas that I need to fulfill my mission of delivering electricity to everyone.
No longer able to subsidize sparsely-populated areas, I either have to raise rates or give up.
"Well that's just the free market" is baloney. A utility's purpose is to serve its population.
A mail service's purpose is to deliver letters to everyone.
In countries where postal service is "privatized" there is still only one letter delivery service-- it's just run by a board instead of the government.
And those "privatized" postal services still have a universal service mandate, required by the law that privatized the formally nationalized entities.
As an aside, the UK's Royal Mail was privatized a couple of years ago. It was sold off at bargain-basement prices, ripping off the taxpayers, to investors who just happened, coincidentally, to be donors to politicians who were in charge at the time. Its "universal service" mandate expires next year.
We'll see how the FrEe MaRkEt handles universal service when not forced to by law.
The American Letter Mail Company wasn't competition. It was a vanity project launched for political purposes that wasn't even in the same game as the USPO, much less in competition with it.
Sadly so many universities are bloated with administrators. Part of the reason the costs are so high. Then they hire adjunct professors who make about as much as a waiter at a good restaurant does. I don't know if TU uses adjuncts but most college's do and this includes Ivy League schools. So the money in general is not going to faculty (that is the full time ones) but the administrators. At some point they are going to have to get rid of the administrative bloat and bring costs down. They are not going to do this willingly. But I think college has reached a price point that is too high that the public is questioning if it is worth the cost.
Student Services and Academic Support (Not all of which are administrators): $9528
That results in $0.52 spent on Student Services and Academic Support for each $1.00 spent on Instruction. In 1999, that number was $0.47 spent on Student Services and Academic Support per $1.00 spent on Instruction. That's not a huge increase in administrators.
The cost of college is largely driven by reductions in state support for public institutions, and the resulting increases in tuition by both private and public schools:
That's fair, but it doesn't change the argument much. If you add the Institutional Support, you get these costs being 87% of Instructional Costs in 1999, and 94% in 2016. That is an increase of 8% as compared to 5% by my original calculation.
I update the router about once a month, just to ensure all the relevant packages are kept current with upstream. So far the only breakages have been in kernel incompatibilities with the ipt-netflow module, but I think that’s only happened once so far - any Arch updates to shorewall, dnsmasq, etc. have been stable.
I've been reading Ars for many years now and I just wanted to say that the clarity this specific article displays in explaining astronomical concepts to a layperson is really impressive and appreciated. Sometimes I get lost in these types of write-ups, but you gave readers the state of the field and why this study - which simply provides evidence that helps likely nix one potential explanation - truly was important in that context. It was all just so digestible and satisfying.
Totally agree.
I loved the implication that one simple 7 hour viewing yielded 15500 events to be filtered and that they could observe a binary star system's change in that time frame. To me, that's awesome!
A well conceived article about building your business and giving novice entrepreneurs a chance to think about earning millions of dollars in revenue. The reference given to animals here in accordance to customers makes it a bit weird but otherwise the whole post is quite informative and interactive to read.
Pure JOY! I admire the sterling character that the Adewumi family has so beautifully exhibited. It's so refreshing after the recent news about rich kids cheating to get into college. (And shall I mention Trump's Foundation, used to buy himself portraits of himself? ) Anyway, Tani, I see you have a very large heart and an incredibly bright future ahead!
Yes, they might. And then again they might not. Probably not. In fact, there’s not a snowflakes chance in hell they will. This is the scientific equivalent of wondering how many angels can dance on the head of a pin. Oh, except now they have a computer model. Plus ça change, plus c'est la même chose
Why is MCAS needed? If the MAX is so similar to old 737’s and no additional training is needed, then why the MCAS? The most relevant question is “is the MAX aerodynamically stable?” If it is, why do we need the MCAS? That needs to be investigated.
If plane at a low altitude at full power is stalling, just lower the nose. That is pilot training 101. Why need a system like MCAS to help. The pilot should be able to disengage the autopilot and take control of the airplane. This should be simple.
My suspicion is that there is an inherent, more fundamental problem with the MAX. Before Boeing rushes a software fix, idependendent entities “(remember we can no longer assume the FAA is independent based on what transpired over the last few days) need to investigate and makes sure the plane is safe.
I for one will not fly the MAX regardless of what the FAA and Boeing say. Their reputation for prudence and safety is gone.
The short answer to your first sentence is that MCAS was needed to give acceptable handling characteristics at high angles of attack. the MAX was deemed similar enough to the NG, such that additional training was not thought necessary, only because of the difference MCAS made.
Stability is a more complicated issue than it might seem, for reasons such as aerodynamic stability being insufficiently damped, and the interaction between roll and yaw. An airplane that is statically stable could still be dynamically unstable, and go into a divergent series of oscillations if not corrected. It is very common for an airplane to be statically stable around all three axes, yet be prone to falling into a spiral dive if not corrected (this is probably what happened to JFK jr.) If you try to increase the stability to fix that, you get an airplane that is susceptible to an oscillation called dutch roll. Most swept-wing aircraft, including airliners, have gyroscopic yaw dampers that operate the rudder to counteract this.
Then there's helicopters... All I know about them is that its complicated.
> The short answer to your first sentence is that MCAS was needed in order to make the MAX so similar to the NG versions that it could be claimed that no additional training was needed.
I think that places the emphasis in the wrong place in a tabloid headline kind of way. The reason for MCAS is so that the 737 Max passes the certification requirement that the pitch controls cannot get lighter on the approach to a stall. It's correct in that clearly the previous 737 were certified as meeting this standard, but it's wrong in that even if the pervious 737 didn't exist this would still be a requirement of certification.
It's probably splitting hairs at this point but I don't think that MCAS was nessasary to avoid having different training requirements between the NG and the Max.
The Max may not have been certified without MCAS.
The existence of MCAS certainly seems to have been brushed under the carpet. It's probably fair to say the reason was to avoid creating additional training requirements.
Perhaps the way to put it is that MCAS was necessary for certification, to correct a handling change caused by the installation of larger engines. Separately, the 737 MAX, in its as-produced form (which included MCAS), was considered similar enough to the NG that additional training was not thought necessary. Once Boeing had ruled out design choices such as a longer undercarriage with the engines moved back, or a larger stabilizer (if the latter would, in fact, have helped), the MAX without MCAS was not an option.
I follow all of this, but something doesn't pass the smell test. Disclaimer, I'm a pilot, former CFII, but I don't have much knowledge about aircraft certification requirements.
I cannot comprehend feature XYZ that helps achieve aircraft certification, that can also be disabled by the pilot. Either feature XYZ is mandatory for certification or it isn't.
I can imagine a feature that provides better handling behavior or safeguarding. But if it can go crazy in a way that it's routine to disable such a feature, it must be mandatory the pilot know about the feature's operation, and they must demonstrate competency at handling the aircraft when the feature is enabled and disabled.
And all of that tells me I don't know the full story yet.
I don't think disabling MCAS (or electric stab trim) should be routine. Given most airliners have given up putting trim wheels in the cockpit I'm sure the reliability of electric trim is very high.
Reading between the lines this system was added as a bit of an after thought. There are plenty of systems which have control of trim so I think they probably didn't give it the respect due to stabilizer trim.
There is always the possibility we haven't got the full story. I'm going to check the full preliminary report from Lion air but from what I've read there is some strange behaviours on the trim system that aren't fully explained yet, even by this half baked fix.
I don't see how MCAS obviates a positive static stability requirement, because it can be disabled. But I admit I'm not familiar with FAA requirements in this area.
If the airplane has substantially different pitch behavior, that usually means there'd be a type rating requirement on the pilot, not a lack of airworthiness certification for the airplane. So I'm not really clear on what behavioral requirement MCAS is mitigating. And further I'm not clear how something that can be disabled can help with either aircraft certification or a obviate a separate pilot type rating.
e.g. fly by wire airplanes have various layers of safeguards in place, and pilots type rated for a particular airplane (or models in that same type) are required to understand those safeguards and how the airplane behaves when they aren't in place.
In the 737 MAX case, it's very weird to me that MCAS is somehow a requirement on the one hand, but then it can be disabled without pilots understanding the alternate behavior on the other hand.
> prone to falling spiral dive if not corrected (this is probably what happened to JFK jr.)
Great post, however, my information was that JFK jr. most likely entered a Graveyard Spiral[1], which is a pilot issue, not a plane/aerodynamics issue.
In short, you think you are flying straight, but are in a turn (so banked). You notice you are losing altitude and gaining speed. In level flight, that means you are nose-down attitude, which you correct by pulling back on the yoke. This would fix both issues.
However, as you are in a bank, pulling back to yoke tightens the turn, meaning you lose altitude more quickly and gain more speed. Loop.
It's a situation that is now trained for in basic flight training.
It is both a pilot and a plane/aerodynamics issue. Spatial disorientation and the tendency of the airplane to undergo spiral divergence combine to produce the graveyard spiral. If the airplane was unconditionally stable in roll and pitch, the actions you describe would not lead to the increasing bank and dropping nose of a spiral.
The point here is that spiral divergence is possible, without any contribution from the pilot (whether disoriented or not), even in airplanes having three-axis static stability.
Hmm...I don't see the need for anything of the sort. The graveyard spiral can be achieved purely due to erroneous pilot inputs, the plane's behaviour is basic aerodynamics:
- you lose lift because the wings are at an angle. Nothing you can do about that relationship.
- the tightening of the spiral is also due to basic aerodynamics/geometry: once you are banked, the lift from the aerodynamic surfaces has a horizontal component in addition to a vertical component. You increase the lift from the surfaces by increasing the angle of attack, you get additional force in the horizontal component. Of course you also get vertical component, so in a normal turn this is fine.
Since there is continuous pilot input, even if the plane were stable in such a fashion as to automatically try to revert to straight and level (which most planes don't, you have to explicitly command exit from a turn), that wouldn't help you in a graveyard spiral.
Now the plane doing this by itself due to instability is an additional problem, sure, but it's not a necessary condition.
I don't think so. Firstly, in your scenario, and with an airplane that is unconditionally stable in roll, there is no tendency for the bank to increase. As the pilot pulls back, the airplane will slow down to the target speed, the pilot will adjust the elevator to maintain that speed, and the airplane will have entered a stable fixed-radius turn, albeit slowly descending because the power is set for straight-and-level flight at that speed. But there has been no aileron input, so the roll stability will bring the wings level. If the airplane was initially trimmed for straight and level flight, and the pilot gets it back to the target speed, it will resume straight and level flight, though not on its original heading.
It doesn't work out this way in practice precisely because the airplane is not unconditionally stable in roll, and exhibits spiral divergence.
You have correctly described what happens to start a graveyard spiral, and when you say "the plane's behaviour is basic aerodynamics" you are correct - but it is the aerodynamics of an airplane undergoing the onset of spiral divergence, and it is that spiral divergence, together with the pilot's failure to notice what is happening and correct appropriately for it, that leads to the increasing bank and falling nose. The bank increases despite the fact that the airplane has some static roll stability and despite the fact that the pilot has taken no action to command it.
"Three types of airplane motion can result from the interaction of yaw and roll:
1. Spiral divergence results when the static directional stability is great in comparison to the static lateral stability (dihedral effect). If a wing is lowered, the directional stability is greater than the roll stability and the aircraft will not sideslip readily. Thus, the dihedral effect is weak and the wing will not rise to the level position. The airplane tends to enter an ever-tightening spiral dive commonly called a graveyard spiral.
Flight Theory and Aerodynamics: A Practical Guide for Operational Safety (Charles E. Dole & James E. Lewis), page 274.
> Why is MCAS needed? If the MAX is so similar to old 737’s and no additional training is needed, then why the MCAS? The most relevant question is “is the MAX aerodynamically stable?” If it is, why do we need the MCAS? That needs to be investigated.
This isn't even a question. The 737 Max is completely aerodynamically stable. It does however exhibit control behaviours which are undesirable.
A fair analogy for this is probably a car which oversteers, in general a normal family car is designed to understeer, because for your average driver that is safer. In the 737 Max the controls get lighter close to the stall because of lift generated by the engine nacelle. The certification requirements require that the controls don't get lighter. Boeing applied what now appears to be a poorly thought out fix.
What might surprise you is that there are plenty of certified aircraft which are actually aerodynamically unstable, at least along the longitudinal axis. For example the 757 has dual yaw dampers and at least one of them needs to be serviceable before flight. The consensus is that at cruise altitude it would depart controlled flight without one of them working.
I think a fairer car comparison would be this: a new power train is fitted to the car, but it sometimes causes torque steer to the right. To overcome that, the steering wheel gets trimmed to the left when torque steer is detected until torque steer is neutralized.
The system detecting the torque steer sometimes has false positive.
Eh, let's not spin it as "the requirements made them do it", they chose to make the new model stick with the existing 737 certification because building a substantially different new plane would require pilots to be retrained, and they didn't want that as Airbus was ahead of them in the development of the A320neo and they needed that commercial advantage to remain competitive.
I'm not sure where you draw the line though? None of this is new, making modifications to existing designs is the aviation equivalent of developing a new feature. Hanging new engines from an existing fuselage, replacing the avionics and lengthening a fuselage have all been done before with reasonable results. Conversely, clean sheet designs have had terrible safety records initially.
Asking a manufacturer to make a clean sheet design every time they make a change is probably going to result in more accidents than it fixes (see the bathtub curve).
The 737 is self certified by Boeing, which is really a joke. Basically a Boeing engineer can sign off and say LGTM with no oversight or independent audit as I understand.
> Their reputation for prudence and safety is gone.
A lot of people felt this went a while ago, see the rudder issues that plagued them during the 1990's and the way they subsequently tried to deny responsibility: https://news.ycombinator.com/item?id=19389983
> If the MAX is so similar to old 737’s and no additional training is needed, then why the MCAS?
That's the problem. The MAX isn't similar enough to older 737s, so MCAS is necessary to change the handling characteristics to be more like older 737s. It's a fix to cover up a lie.
> If plane at a low altitude at full power is stalling, just lower the nose. That is pilot training 101. Why need a system like MCAS to help.
They know this, but different planes still do that in a different way. MCAS was supposed to cover up the fact that the MAX did this differently.
> The pilot should be able to disengage the autopilot and take control of the airplane.
But MCAS is not the autopilot, it's something that tried to make the plane behave like a regular 737 during manual control. So turning off the autopilot does nothing; it's already off.
The problem is clearly that Boeing wanted to pretend the MAX flies just like an older 737. It doesn't. If they'd just admitted that and given pilots extra training, all this mess wouldn't be necessary.
And that greed is ultimately what caused this situation. Had they been more honest, these crashes wouldn't have happened, but they would also have sold less planes.
The Max has more powerful engines, mounted further forward on the wings (out of geometric necessity), and as a result has an aerodynamic center of lift further forward.
From the addition of MCAS, I gather (but don’t know with certainty) that they couldn’t make some certification requirement without MCAS.
"If plane at a low altitude at full power is stalling, just lower the nose."
Except as can be seen time and again basic instinct can kick in "damn, plane is falling, I need to be higher" and pilots have been known to pull back on the stick to get height.
A pilot that deals with a stall by pulling up has failed their training.
As I recall, we practiced low speed flight and recovering from a low speed stall either the 2nd or 3rd time I ever went up in a Cessna. Power on stalls were a few days later, they are quite different.
I never did get my license, mainly because I experienced moderate nausea / motion sickness which I thought would abate after a dozen flights or so, but never really got over it.
The problem isn’t that pilots can’t or shouldn’t be relied upon to detect and recover from stalls or near-stalls by increasing throttle and decreasing pitch.
The problem appears to be that a new system, added for the purpose of making a new plane with different handling / characteristics behave the same as an older one for training purposes, is malfunctioning.
The plane could be perfectly safe without MCAS but pilots would have had to be recertified.
It depends on what you mean by "perfectly safe". Many people believe that having the yoke effort decrease at higher angles of attack instead of increase is not very safe. That's why the FAA certification requirements force manufacturers to do whatever is necessary to make sure the yoke force increases with increasing angle of attack, so the pilot has to exert more effort to pull up at higher angles of attack. Without MCAS, the 737 MAX as designed would not meet this requirement.
Never underestimate the relationship between the rich and the ignorant. These people trade tobacco for a synthetic chemical......cancer just comes sooner I suspect.
