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The Airbus system certainly does override pilot commands. It doesn't matter if the autopilot is disengaged. There are situations even outside of normal law where the system will prevent the pilot from entering a stall.


Except they didn't "follow procedure." MCAS trimmed down repeatedly on one instance for 9(!) seconds and yet the pilots waited 3 seconds longer to counteract that with an electric trim up command on the yoke. The procedure is not 1. Let MCAS do its thing 2. Pull back on the stick 3. Hit the stab trim cut off when you have had enough. Attempting to counteract the the trim down command with manual trimming commands should occur continuously "as needed." If you don't attempt to override the trim runaway with manual trim up commands on your control yoke you aren't following the checklist. On the 737 you can see the trim wheels move and if unintended follow the checklist.

The pilots didn't do that at all. Sustained manual trim only occurred after MCAS kicked in again at 5:40:27 and the pilots still waited before invoking the trim up command. The pilots never invoked sufficient trim up to counteract the automatic trim down command. Again, there is a reason the trim controls are on the control yoke in the first place. Of the three major MCAS trim down commands the pilots only stopped the second one with manual commands after it had already pushed the nose dangerously low. If the pilots had simply invoked manual trim promptly and counteracted the erroneous trim manual trim would have been successful after invoking a STAB CUT out.

If you think the pilots are following procedure why at 05:41:46 did: "the Captain ask[ed] the First-Officer if the trim is functional." ? That doesn't make sense, of course the trim doesn't work, the STAB TRIM cut out switches were engaged! But the response by the first officer was that "The First-Officer [has] replied that the trim was not working and asked if he could try it manually." which again doesn't make sense. But it gets worse because this happened a FULL MINUTE after the stab cut out switch was engaged, which means that neither pilot tried to manually trim the aircraft during that time at all!

But it gets better: "At 05:40:27, the Captain advised the First-Officer to trim up with him. " Which again doesn't make sense because it wouldn't make any difference if the both pilots were trimming up or not, the stabilizer doesn't move any faster.

My conclusion is that the pilots didn't know the checklist but its hard to tell because the CDR isn't presented completely.


You're right that the service bulletin doesn't talk about selecting selecting a sufficient nose up trim because control of the aircraft using manual trim is a continuous action performed in combination with the pitch up command of the control yoke. Just pulling up on the control column and activating momentary manual trim isn't sufficient or intended. I understand why people think the checklist implies that performing a STAB TRIM cutout occurs instantly after the autopilot is disengaged because of the "if runaway continues" language.


All these points have serious problems though.

1. The $500 billion spent on welfare and other income support programs is usually significantly more generous than what a recipient would receive through Yang's proposed UBI. The fact you don't have to cover some people who already receive even more generous benefits doesn't "save you money" in any real sense. There is no real reason someone would choose a UBI over these programs except paperwork.

2. A VAT only gets you $800 billon a year when you need at least something like $3 trillion. This policy is also a little hard to understand if you are left leaning; don't you want to spend new tax revenue on something like universal healthcare, reducing the cost of college or renewable energy expansion? If you raise taxes to pay for a UBI it just becomes harder to raise tax revenue for any other priorities.

3. The roosevelt institute study assumed that the economy was almost completely constrained by demand to the point where even if the UBI was funded entirely through debt the net result would be an economy 13% larger after eight years. Leaving aside whether you agree with their simulation(I don't); this is an incredibly risking bet, if you are wrong that the economy is constrained by demand you have dramatically increased the federal deficit and probably caused a fiscal crisis in the process which would, of course, dramatically shrink the economy. It's interesting to note that the Roosevelt study doesn't actually model Yang's proposal of financing essentially the cost of a UBI through taxes/ spending cuts with the rest through deficit spending and it's hard to see how he came up with the numbers here.

4. So assuming you can save $100-200 billion on other government programs and you get everyone who uses welfare assistance to sign up for a UBI instead you aren't even halfway to the $3.6 trillion dollar price tag.


The problem with universal basic income is that none of the ways to pay for it are palatable. Let's assume for instance that we want a UBI of something like 20% of per capita gdp. Either we (a) cut spending from existing government programs or (b) raise taxes.

It is often suggested that the UBI can replace existing social welfare programs and save money in the long run by cutting out administration costs. First, administration costs are already quite low, social security administration costs in the US for example are usually around 2-3% of total outlays and there is no real reason to believe that similar old age pension programs in other countries are any less efficient. Secondly, existing government programs are usually significantly more generous than a proposed UBI to the recipients of such programs. Cutting existing spending means that the existing users of government welfare will suffer a massive drop in living standards. Leaving outside the moral consequences of imposing austerity on the most vulnerable in society this point is almost never acknowledged by proponents of a UBI.

Raising taxes is the second option but this is even more problematic than diverting existing government spending. Western governments already impose significant taxation on citizens. If you are living in a rich country with tax receipts over 50% of GDP increasing taxes by over 40% basically means restructuring your entire economy. Since income taxes are already quite high you will almost certainly need some mix of increases in payroll and sales taxes to meet the fiscal demands of a UBI. The poor can't reasonably be exempted from this increased taxation as their income will either be hit by increased consumption taxes on almost every good or service they purchase or their after tax income will be hit by the higher payroll taxes. Trying to means test the payroll tax increase won't work as governments will no longer be able to raise enough income to afford a UBI if they try to carve out exemptions for the poor and lower middle class. Assuming you are comfortable with these tradeoffs and the perverse incentives usually created as people try to avoid the large increase in taxes you will be faced the reality that the UBI will not go nearly as far as it would before the additional taxes are imposed. Not only have you given every worker a pay cut you have also increased the price of almost every good they could conceivably purchase with their new income. Finally, such a large increase in taxation will almost certainly impose a dramatic cost in economic activity. Increasing taxation from 50% to 70% of total economic output is far beyond what even the richest countries can support in taxation. No Scandinavian country is even remotely close to this level for example.

The net result is a trilemma in implementing a UBI that cannot be avoided:

a) if you reduce the level of the UBI below what a reasonable person could subsist on you defeat the entire point of having a UBI in the first place b) if you cut existing government spending welfare recipients and existing users of government programs will be massive net losers c) dramatic increases in taxation are beyond what is generally considered possible to put it politely

Silly articles like this on the UBI never bring up any of the public policy issues that must be addressed to implement a UBI and it's pretty clear why. The UBI as I see it proposed incessently is basically the perpetual motion machine of political thought


I suggest you look at Andrew Yang’s 2020 platform of Freedom Dividend and explanation of how to pay for it.

Yang would offer each person an annual choice between existing benefits or an unconditional transfer payments (UBI). This allows for an easier transition to more UBI while preventing lapses in important benefits for those who need it.

As for the pay-fors: You do NOT need a policy proposal to be revenue neutral (ie 100% paid for by spending reductions and/or tax increases) if it grows the economy or if it saves costs elsewhere in the system. This is true of any policy. We have never paid for our spending during and after WW2, but that doesn’t matter because we grew our economy as to make that debt trivial to the size of the economy.

In UBIs case, we have strong evidence from studies that it tends to improve health (especially child health), reduces crime, and increases business creation (a stable albeit small income is a fantastic platform for entrepreneurship), among other benefits. How much does it cost society to fail to eradicate below-poverty incomes? How about failing to end involuntary homelessness? UBI is the cheapest way to get those things.

Back to Andrew Yang’s plan: 1) Institute a 10% VAT. 2) Save on reductions in social services (to the degree Freedom Dividend is chosen) 3) Remaining balance paid with deficit spending, growing the economy and reducing upstream costs.


Except he doesn't explain how to pay for it as far as I can tell. He has four funding sources that don't come close to adding up to the $3 trillion he would need to fund a UBI. The $800 billion for a vat is incredibly generous but even assuming that he can only come up an additional $500 billion by assuming that everyone will prefer a UBI over other government programs. He also assumes $100-200 billion will be saved by the government due to lower costs of other government programs.

Even assuming everything adds up that still only gets you to $1.5 trillion, you still to come up with another trillion at least! Borrowing the money will result in the US running the largest peacetime budget deficit of any developed country ever. A budget deficit of 15% of GDP would be at least 3 times what the budget deficit was at the height of the Reagan era. It's simply disingenuous to claim that this is par for the course for advanced economies. It isn't.


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