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that's the same boiler-plate reason they give for every firing due to an embarrassing mishap.

google 'for loss of trust and confidence in his ability military' and look at the news tab, every embarrassment to a military group gets thrown that bone.


Loss of trust and confidence is huge in military (and adjacent) circles. Many of these roles involve ordering others into situations that are likely fatal.

There’s no boilerplate involved. Trust and confidence are immense in command roles, particularly in a role like CO of a trust and evaluation squadron.

It’s also important to note that the Marine Corps itself did not lose trust in Colonel Del Pizzo - as per this article he was offered follow-on orders of his choice.

https://www.military.com/daily-news/2024/10/31/pilot-of-f-35...


I think that’s just to make the shafting a little bit softer. You are still being shafted for valuing your own life over an expensive airplane.

That plane is significantly more valuable to the American people than his life is. That plane cost the entire federal tax bill of 1000 senior software engineers. If he's not willing to risk his life to keep it in the air, he shouldn't be flying it.

seems reasonable to me. If someone lost a 110 million dollar asset in a questionable way, I wouldn't have trust and confidence in their ability either.

Flying cutting edge military jets isn't exactly a human right.


That's all well and good, except the next pilot facing a potential loss of aircraft will probably hesitate (worrying about getting shafted), and keep trying to recover the craft until it is too late. Then you have a crashed plane, and a dead pilot. People make better decisions when there is precident for a no-fault management style.

No, because he was not fired for ejecting from an unsafe aircraft, which is what you're claiming would be the situation where the pilot would hesitate. He was fired because the General didn't feel he'd shown the judgement and skill commiserate with his station.

The cardinal rule for an in-flight emergency is that if the plane is flying, you're OK in that moment, there's no need to panic.

He was fired because as a test pilot, he panicked after the HUD malfunctioned, and ejected from an aircraft with an hour's worth of fuel that was not losing altitude or experiencing any mechanical failures, and did not make even an attempt to verify his primary instruments against the backup secondaries, or to use a functioning backup radio.

He could have used the backup radio to contact the tower to verify his altitude, speed, heading, rate of climb, etc and then get vectored back to reunite with his wingman ,and followed his wingman in for a landing.


> No, because he was not fired for ejecting from an unsafe aircraft, which is what you're claiming would be the situation where the pilot would hesitate.

That's not quite right. The pilot doesn't have an outside oracle who tells them the truth if their aircraft is beyond saving. They have to make that decision under stressful circumstances and having only partial information about the world. Making that decision, to declare their own previously safe aircraft no longer salvageable in their own head is where the hesitation might happen.

I'm not saying that this was a bad call. The General has much much more information than I do. It is entirely possible that this was so egregious a case, and the plane was so obviously flyable that firing the pilot was the correct decision. I don't know.

What I'm saying is that you can't just say "oh they won't hesitate, because their plane will be unsafe". Because the hesitation (if it happens) happens before they decide that their aircraft is unsafe. Instead they will spend possibly valuable seconds thinking through if they truly have tried everything. If they are perhaps mistaken. If they maybe will lose their jobs because there was something they haven't seen clearly enough, but in the cold harsh light of an investigation will mean that they made a mistake.

Pilots are already heavily biassed against ejections. It is embarrassing, even if it was justified. It is a deviation from the routine. It is potentially deadly, potentially ruinous to their ability to continue flying on health grounds. This might be one more factor now which will bias them against ejecting. I hope the General made the right call.


> commiserate with his station

I do, but perhaps this was meant to be "commensurate".


kinda makes you wonder about his opinion on the overall reliability of the F-35 if he made that call.

From what I read that seems plausible given the pilot was a seasoned test pilot; so it seems odd he was just being panicky.

Imagine just being struck by lightning, loosing main displays, and being at 1200 feet. All on top of flying in a plane with a reputation for electronic failures.

I'd be concerned too that the plane was about to freak out. 1200 ft isn't far.


2000 hours isn't all that seasoned, and he had less than 50 hours in that type. He was accomplished all right, but not what one would call seasoned.

In fact, the root of the word "seasoned" means "prepared" and he clearly was not prepared for the events leading to this incident. That through no fault of his own, hence he was not formally disciplined.

The Marines expect someone of his position to perform above and beyond their training. He didn't, so he lost that position with no formal discipline.


Why are people in other threads saying that he was some sort of expert or that he lost an expert position because of this?

This.

Back in the day, a carrier deployment w/o the loss of an aircraft was considered subpar because it was taken as evidence of not pushing the boundaries enough.

Or so I was told by a USN pilot.


That might make sense if you valued the life of a pilot more than an F-35, or even a large number of F-35s, but at the end of the day, that simply isn't true.

Sometimes you will save the jet, sometimes you will lose both. Military policy is not "better safe than sorry". There is some number of jets, perhaps less than 1, where it is better to have a dead pilot than an unnecessarily crashed plane.


Precisely, the next pilot will not bail out so quickly, saving a $100M plane. Encouraging pilots to exhaust all options before they eject is the entire point.

On the other hand, the USMC has invested considerable time and effort in training this person to operate the F-35. Replacing him with someone else will take time and money. For the organization that invested all that into him to say ‘nope, we don’t want you to fly these things any more’ is itself a massive waste of resources.

Sure, that makes sense as a waste if you are operating under the assumption that they have no questions of ability and are simply being railroaded, and will never fly again.

In this case, the pilot is still flying. They are just not leading as prestigious and high risk command, because there are doubts that they suitable. There is no new cost, they are just rotating the roster. he will fly elsewhere and a different pilot will take that role.

It is only a loss if you double down thinking that he was the best or only fit for that role.


He's certainly a highly trained Naval Aviator, but he had very little time in the F35.

He was fired from command, not stripped of his wings.

And now you've created yet another layer of FUD for all future pilots.

Shit can and will happen. The only real thing questionable is the damn aircraft.

Do you know how many things have gone wrong with the F-35? [0] It was a shit situation, the book was (unsurprisingly) crap, and you are potentially in a very expensive death trap. The guy choose to live. Honestly, his real mistake may just to have been willing to fly a F-35 in the first place.

[0] https://theweek.com/us-military/1020858/the-f-35-fighter-jet...


Ehh. While I understand your point, I think we should also ask ourselves if it’s reasonable for a fighter to cost $110m a pop.

The customer demands the best, because if they do not have it the adversary will have it, and that is unacceptable. Even given that 110 million (assuming current 2024 dollars) is pretty cheap: the Grippen comes in at around that based on Brazilian purchases and is much less capable, being a 1990's design.

Woah, I could not believe this post, until I looked it up. Wiki says: <<On 24 October 2014, Brazil and Sweden signed a 39.3 billion SEK (US$5.44 bn, R$13 bn) contract for 28 Gripen E (single-seat version) and eight Gripen F (dual-seat version) fighters for delivery from 2019 to 2024 and maintained until 2050>>

That is 150M USD per plane. However, this might include maintenance costs, which would make it different from most F35 purchases that I have seen. Does anyone know any more specific details?

Ref: https://en.wikipedia.org/wiki/Saab_JAS_39_Gripen


I'm not really sure what maintenance costs over that period in a contract look like: certainly getting them down to a number introduces a bunch more risks for someone (inflation etc), and not having them has other risks. Getting numbers here is sadly hard, and I agree my comparison might be not apples to apples.

Even if the flyaway cost of a Grippen is $50 million the number of planes to accomplish the same mission is a lot more, and some of that number will be lives lost. I'm pretty confident it's within half an order of magnitude of F-35 price.


The wikipedia page lists 9 digit flyaway costs for other Gripen versions, so even if it includes some support, the bulk of the price is the jet.

Edit: 5th generation jets are just incredibly expensive. I can't imagine how mad Turkey was when the US bilked them for their F35s, keeping both the jets and the billions Turkey paid.


Shouldn't have planned to let Russia see the radar returns then.

Interesting. My understanding is that the US refused to deliver after Turkey bought S-400 systems from Russia, and will still sell the F-35 to Turkey if they stop. Do the systems share radar returns with mother Russia or what exactly is the concern?

https://web.archive.org/web/20240202005500/https://ca.news.y...


Bingo. These systems are not packaged goods, but come with services that depend on getting a lot of the data to improve the system, and it's hard to control how they share. An air defense system is part of a network.

I think that is a fair question. Cheaper would obviously be better, but unless or until they are cheap, they are not disposable.

I think Ukraine is lots of evidence that of how important it is to have air superiority, even at extreme cost. If Russia had gained air superiority as many expected, the war would have been over shortly.

https://mitchellaerospacepower.org/wp-content/uploads/2024/0...


A 737-MAX10 costs more, and it's almost all empty space.

A supertanker costs more and it’s just empty tanks.

>What does that even mean? What would a middle/center party do, exactly?

Forget the wording 'centrist', parent is trying to describe the need for a party that seeks allies from all angles rather than trying to produce outrage towards specific groups of people in a lazy effort to foment in-party support and credit.

In recent years, I guess due to success of certain parties, everyone has decided that it is in fashion to have a group to demonize - to hate. This (necessarily) creates a group of disenfranchised people that have an axe to grind.

It used to be that political parties demonized far entities that were as far outside the voting American public as was feasible; now it's fashionable to attack people that constitute American voters. Now we have hordes of people that were demonized by one side or the other, and a lot of them want to vote one way or the other out of pure spite rather than political interest.


> Forget the wording 'centrist', parent is trying to describe the need for a party that seeks allies from all angles rather than trying to produce outrage towards specific groups of people in a lazy effort to foment in-party support and credit.

Well politics is about making choices where consensus is unattainable. By nature of not being consensual, there will be some angles from which these choices are undesirable. So attracting allies "from all angles" is essentially the same as saying "whoever is not my ally comes from no (reasonable) angle", which is precisely what the democrats are being described as doing in the article. They are the utmost "centrist" party in a way.

The answer to the demonization issue is not to pretend everybody must be your ally, it is to acknowledge that one can reasonably disagree with you, and be willing to engage with your political opponents rather than treat them as enemies, to reach an agreement acceptable to most (though not all).


> Forget the wording 'centrist', parent is trying to describe the need for a party that seeks allies from all angles rather than trying to produce outrage towards specific groups of people in a lazy effort to foment in-party support and credit.

Fair enough. I'm all for breaking up the duopoly.

However, the strategy of scapegoating and creating enemies is hardly a new phenomenon. It's as old as politics itself. More recently, I'm old enough to remember Reagan railing against "welfare queens". In 1968, George Wallace ran for President, and won 5 states, on a platform of racial segregation. There was also the McCarthy era, of course, where there were supposedly enemies, Communists everywhere in the US. And George W. Bush weaponized patriotism after 9/11, painting anyone opposed to US imperialism as supporting the terrorists. (This same happens today to anyone opposed to US imperialism. They're called antisemites and supporters of Hamas.)

In the end, though, polls usually show that people vote based on their pocketbooks. Economic issues are almost always most important and salient, despite all of the other political commotion.


so long and thanks for all the fish.

I love wireguard and the configuration methods compared to openvpn.


he retired last year, but it's amusing to think of some exec-level ceo going onto forums to peddle merch.

with BB's stock performance : maybe?


chibios is great, but I haven't followed their culture or licensing in a few years now.

my experiences then would lead me to recommend it, though.


ChibiOS doesn't really compete in the same space as QNX. It's a single address space executive that's more like FreeRTOS than QNX.

because it's a unique taste , a unique method, and a cultural significance for some people -- no one is forcing you to eat it.

Why would anyone eat fugu or collect wild mushrooms?

It's fun and interesting. That's why. Danger be damned.


> Why would anyone eat fugu or collect wild mushrooms?

I can't speak to fugu, but collecting wild mushrooms is statistically one of the safest hobbies in existence.


It's the eating that's the real challenge

The danger is part of the appeal. When somebody gives you a mushroom called "the sickener," which is apparently edible with an appropriate combination of brining, fermentation, soaking, rinsing, and boiling, it's a little hard to resist the temptation to prove everyone else wrong and turn it into a tasty treat.

Brings fugu to mind. I wish I could get a scientific answer to whether there's actually a high associated with it or if that's just in people's heads.

one of the quickest ways to ruin the way an established boat plan 'swims' is by adding a tall rig after de-masting.

it's extremely enticing to 'add more sail' to a boat in order to squeeze more speed out of it, or achieve easier lufting.

turns out that marine architecture is a lot harder than one thinks at first glance, and just about everyone that tries to tweak specs afterwards does so in such a way that makes the boat categorically worse.

(don't ask me how I came to realize this after many dollars spent)


Sounds like the old maxim around boat ownership still holds: "the two best days in boat ownership are the day you buy it and the day you sell it" :^)


the joke is, "the 2nd best day of your life is the day you buy your boat" which makes the listener think "2nd? oh, must be after your wedding/birth of child"

and then you say "the 1st best day is when you sell it"

rug pull


The same applies to airplanes. Which combines into the "If it floats, flies or f.. ehm.. fornicates, it's better to rent it"


Yeah, I seem to remember the full phrase is something like, “Advice for millionaires: if it floats, flies, or [fornicates], rent it.” Advice does not apply to billionaires, which is a category Mike Lynch may have snuck into depending on whose reporting you believe.

As distasteful as the last part of that advice it, I can see the sense of the rest of it. You need to have enough money that the inevitably high ongoing maintenance costs (and I guess depreciation) simply aren’t a concern, or even something you have to think about because you have people to take care of it for you.


100LL and a quart red bottom paint cost the same no matter how much you make. The 3rd category scales with income.


We used say boat stood for. Break out another thousand


A “boat buck” Is $1000. How much was the bottom paint? All up pretty cheap, 7 boat bucks.

Boats are just holes in the water that your throw money into.


Bottom paint is about $250/gal. It takes us about half a day to sand the hull and roll on a layer. My 40' sailboat can be covered with 1 generous coat with 1gal with a little left over. $7k for bottom paint must either be a huge boat, an expensive crew, or both. It's just not all that expensive if you're willing to put in a little effort.


I’m no boat expert but doesn’t your statement imply some level of ease of dragging a boat out of the water to perform this operation? Something tells me that pulling a 40 foot sailboat out of the water, turning it over, painting it, and returning it into the water isn’t necessarily the most straightforward operation. A lot of complexity is probably loaded into “it takes us” and if we took a gander at the hourly rates of everyone involved in said operation as well as the upfront cost of the equipment to perform said operation as well as the safety measures required to execute the operation properly I feel like we would be a lot closer to the $7k number than the $250 number


You just take the boat to the travel lift and it hoists out pretty easy. Under 1 or 2 boat bucks for in/out lift, dry storage, and paint if you DIY is reasonable for smaller vessels, like under 30’.

The tough part is scheduling and finding a boatyard if there’s not one close.

Your nautical mileage may vary


You have to pretend the DIY is free, or even fun. Boat people are usually not cheap to hire.


> Boat people are usually not cheap to hire.

Costs a lot of money to make people put up with boat owners.


If you don't enjoy working on boats owning one sure would get expensive. I guess I'm lucky in that I don't have to pretend? Sure beats office politics, I wish it paid nearly as well as computers.


This can be done for free by just beaching the boat and working during low tide. Although that can be illegal nowadays in some places. Plus a 40 foot boat is much larger than required for cruising anywhere you want- if your boat fits on a trailer it is not only easy to paint, but probably can get by without any.


I didn't factor in haul out and storage because that's a separate thing from bottom paint. Haul out and transport costs about $1k/yr and storage cost over the winter is a further $1k.

Hourly labor rates are $0, I share ownership with 2 other people and we all pitch in.


Turning it over seems unnecessary. Good point overall, though.


If you're an engineer, I'm just going to x3 to x10 that time estimate to come to something realistic, just like I do with the engineers at work.

That way it includes going to buy the paint and sandpaper, putting the boat in a drydock or otherwise on land, finding and dragging out the tools and getting power to them, drying the boat, cleaning it, eating, toilet breaks, taping off the edges etc, letting the paint dry, cleaning up everything afterwards, putting the boat back into the water and probably tons more that I missed.

x5 sounds about right for this one.


It depends. For example, if the previous paint contains environmentally harmful compounds, you can not sand it without the infrastructure to collect the dust. The details depend on the location (regulation), but typically you need to hire this out.

Sanding takes multiple person-days and can be the wrong method (depending on details). Media blasting (like soda) is much preferred but requires machines and infrastructure to collect the run-off. In ideal situations, sanding is not necessary at all.

It can be several boat bucks, or just about a hundred dollars. It depends.


It does contain harmful compounds. It wouldn't work to prevent growth otherwise. You use a random orbit sander hooked up to a shop vac just like when you sand anything else (unless you prefer dust going everywhere).

For a 40' sailboat it doesn't take multiple person days, it takes about a quarter of a person day. More if you really have to take off a lot of layered up material. And you're right, blasting would work better in that case.


> It does contain harmful compounds. It wouldn't work to prevent growth otherwise.

Nowadays there exists bottom paints such as polysiloxane based ones that work by creating a very hard and smooth surface that critters find it very hard to attach to, rather than poisoning them.


Interesting! I'll look into that. My boat is overdue for a full paint job so that could be an option.


There are levels of toxicity. For some old paints, allowing the dust or run-off from pressure washing to touch the ground would be violating some regulation. Removing those old paints is more complicated. They need to be removed completely and cleanly, so sanding is a bad choice.

This isn't the case for any paint now purchasable, but most still contain biocides that you want to avoid for your own health when cleaning or sanding.


No, it's not an "estimate". It takes half a day. If it took 5x that I would have said so.


7k$ is about what yards quoted for such a job in NorCal. It's easy to DIY if you know what to do, but (1) it's a nasty job (2) it's toxic (3) it takes time and (4) you still end up paying about 2k$ if you're thrifty (in NorCal). I both hired and DIYd the job and it's a wash as to whether one prevails over the other. If I were doing nothing else but boating fulltime, I'd DIY it. But I have a job and family.


It is a nasty job, respirator with VOC filters mandatory and the clothes you wear doing it will never be the same again


Hi, 45' boat owner here. Steps are pull the boat out by travel lift and block it. Power wash the bottom. Put up dust barrier. Don tyvek suit and mask. Sand with dust hose. Power wash the bottom. Paint first coat. Dry. Paint Second coat. Dry. Lift boat move blocking pads. Paint pad area. Dry. Paint Second coat. Dry. Launch boat by travel lift. Paint is $320 per gallon I need 2 gallons and a quart. Total time is 2 days if they hustle, 3 if the pull is late in the day. Lucky for me, they have not found blisters or any thing that takes fiberglass work, that adds time.

Last time I had it done it was $6450 including tax. 7 boat bucks.


Your process, while undeniably more correct than mine, is substantially more involved. Mine goes like this:

1. In the fall, drive the boat onto the hauler's trailer, unstep the masts, and transport it to the yard. Place on blocks and pressure wash.

2. Winterize the boat, wait for spring.

3. In the spring, break out the shop vac and sander and sand the hull. Since it's a multi season ablative paint, don't sand it all off--just enough to smooth it out and get the dried, hard top layer off.

4. Roll on a coat of paint.

5. When the truck arrives to splash the boat, slap some paint on the spots where the stands' pads were, and where the blocks were under the keel.

6. Step and rig the masts.

7. Splash the boat and go sailing.

Steps 3-7 take place on two consecutive days, along with a bunch of other maintenance activities.


I find sailing to be a fun low cost, sometimes even slightly profitable hobby… I own a very small (17 foot) cruising sailboat I maintain myself and get endless fun for less than the average teenager spends on a cell phone. It has an even smaller sailing dinghy/tender I built myself from old redwood fence planks. It would be the last thing I would sell even if destitute- because although small I could live on it for free, and can also use it to get fresh seafood for free- not to mention traveling without fuel!

(to paraphrase Sterling Hayden) my body is only about 6ft long… I sleep as well and have just as much fun on a 17 foot boat as I would on a 184ft boat- and despite being small mine is much more seaworthy than Bayesian was.


I just learned about the Aviation Monetary Unit, or “AMU”. Same thing.


This is true in many things. Most car mods make the car objectively worse unless you really need the niche thing the mod does - and even if you think you do, be really sure.


I'm a full-time RVer and see this all the time with diesel trucks. The trucks get "deleted" and modded for more power and to disable the DEF system. Almost everyone I've known throughout the years begins having transmission trouble within months, especially after heavy load. A few swear by it. I've got a very expensive Cummins and I'm hellbent to leave it stock (and under warranty).


the issue isnt that they disabled their DEF system or deleted their DPF or EGR, it's that they probably installed new ECUs or flashed new fuel maps or something and boosted the power beyond the torque abilities of the transmission attached. In a lot of diesel RVs the transmissions are normally good to 2,000lb-ft, but the engines can be pushed beyond that pretty easily.


My truck owning friends like to blow through transmissions at 50-60K miles by driving their trucks like sports cars and aggressively short shifting while on power. None of them do “truck things” so it’s always a head scratcher as to why they continue to do this.


DEF system: <https://en.wikipedia.org/wiki/Diesel_exhaust_fluid>

(Emissions control, reduces NOx in diesel exhaust.)


I swear the older pre-def cummins engines got like 15% more mpg than the def ones. but RVs have been getting heavier too.


AFAIU modern diesels have lower combustion temperatures in order to limit NOx formation. I imagine this comes at a cost in thermodynamic efficiency.

Similarly particle filters, catalytic converters and whatnot reduce efficiency via exhaust backpressure.

So all in all, reducing non-CO2 emissions do come at a cost in CO2 emissions (or fuel consumed, if you like). Is it as much as 15%? No idea.. And is it all worth it? I'd argue yes, old-school diesel exhaust is nasty stuff.


Yes, this is the exact trade from Dieselgate, as well - higher combustion temperatures increase efficiency, reducing CO2 output, but at the expense of much higher NOx production. It’s easily 15% or more.


Exhaust back pressure is not an issue at all on diesels because they all run big turbos.

As for your later point...I very much concur. I started masking (n95) during the pandemic, and haven't stopped. I have a... large number of health issues including several respiratory ones. Exhaust in general really is nasty stuff. I live in pretty quiet smallish (100k) town, and it can be bad enough around here with all the pollen, but I wasnt recently on a whirlwind trip through the north east that saw me visit the dense urban cores of DC, Philly, Manhattan, and Boston. The difference in odor on the occasions I'd take my mask off on the sidewalk were kinda shocking as someone not used to it.


Out of curiosity do you live in the Great Lakes basin? I moved from Indiana to the West Coast, and I am always shocked at how bad the air quality is when I go back, even in rural areas. During wild fire season I monitor AQI, and when I zoom out I always see that Indiana is just as bad as the smokiest days on the West Coast.

Something about the large, hardly noticeable depression traps bad air at a regional level. I wouldn’t move back for a myriad of reasons, but everyone is always surprised when I list air quality as one.


Similar migration (IN->CA), it has changed my life. I had the worst sinus/migraine issues growing up and my breathing has dramatically improved after moving out of Midwest, even compared on the worst wildfire weeks out here.

Coming from NWI, I know the mills had a lot to do with subpar air quality, but I had similar issues when I lived on the far Northside of Chicago so it seems to be more regionally affecting.

It's a similar top reason on my list to not living there long term again


Same with the sinus infections. Cold air + pollution = two weeks of sinus infections every winter. I haven’t had one since leaving.

North Carolina. Locally it's not so much exhaust type stuff, but all the damn pollen, which I'm somewhat allergic too. Pine trees for miles. I'm about 50 miles inland from the coast so lots of wetlands so in the summer (Which means basically... late March through mid October - it's going to hit 82 here toomorrow) it's oppressively hot and humid.


> Exhaust back pressure is not an issue at all on diesels because they all run big turbos.

Not sure what you're arguing here. Isn't it quite obvious that resistance in the exhaust system means that the engine has to do more work to push the exhaust gases out; work that otherwise could be used to turn the crankshaft. Now of course a lot of that extra energy is wasted in any case, particularly if there's nothing like a turbocharger to make use of it.


Practically all diesels have turbos. You have literally have to go back to tiny tractor engines form The 60s to Find ones that aren’t. Turbos already provide a ton of back pressure. What’s downstream of that is pretty irrelevant


My tractor from the early 00s doesn't have a turbo. Plenty of VW and Mercedes Benz cars built in the 80s and 90s don't have turbos.

Backpressure aft of the turbo is something you really want to avoid because it makes the turbine much less effective. The whole point is to use a pressure and thermal gradient to do work.


Ford and VW put a naturally aspirated diesel into their vehicles up until the early/mid 90s.


Absolutely none of which have DPFs or EGRs.


Backpressure to the turbo reduces the efficiency of the turbo, no?


I was under the impression the engine had to be run hotter in order to break down the NOx particulates in the exhaust gas recirculation scheme which led to higher fuel burn.


No, it is a lower temp which results in less burn hence the need to recirculate the exhaust back through to completely burn it....


hmmm interesting. In a gasoline engine with high temperatures, NOx is produced, but it is fixed by the catalytic converter. So I guess that's not possible with a diesel, so they have to lower temperatures. That must lower the efficiency of the engine because (I think) the temperature difference governs efficiency.

https://www.natso.com/what-is-the-difference-between-exhaust...

Here is a quick overview of how the system works.

Currently only smaller engines are EGR+DPF only. It takes having an SCR(&DEF) system to reduce emissions to legal limits on most larger engines now and the technology has been combined to have an engine with EGR+DPF&SCR(&DEF).

There are issues with engines and the active regeneration that has to occur in order to clean the DPF(basically engine has to get very hot and burn out the buildup) and also issues with DEF, which is an ammonia solution, both with the electronic dosing units failing and solution purity.


I’m curious how combustion temperatures are lowered like you say - is it a pv=nrt relationship hinging on changes in compression ratio or something like injector technology?


Yes, the latest generation diesel engines have lower compression ration than engines from a couple decades ago. Maybe something like 16:1 instead of 19:1. But also exhaust gas recirculation: https://en.wikipedia.org/wiki/Exhaust_gas_recirculation


The U.S. diesel tuning crowd seemingly never discuss air/fuel ratios. This is a huge mistake. Also it's important to understand how much torque your transmission is rated for and to not stray beyond it. It's possible to reliably extract more performance than the manufacturer supplied but you have to understand what you're getting into. Turning it up to 11 and "rolling coal" is gonna get expensive, and it's super dumb.


Really depends on which crowd you're talking about.

The "I bought a tuner" or "I bought a kit" guys don't care or know enough to care.

Once you start talking about people who are reading turbo specs and whatnot people do very much care (because turbos and injectors are expensive and you want them both to be compatible so they get the most out of each other).


I disagree the diesel crowd doesn’t discuss air/fuel ratios but perhaps I’m misunderstanding something. Sizes and types of turbos, fuel pumps, injector nozzles are frequently discussed. I do agree rolling coal is dumb but most/many daily diesel drivers don’t like it either, have always seen it as kind of a high school thing.


Maybe they've wisened up more recently but I've never seen an AFR gauge in a tuned diesel in the U.S., however they're as common as EGT and boost pressure monitoring elsewhere.


You can infer the same information it would get you via boost and EGT and whether or not your exhaust visually indicates unburnt fuel. You also don't need super precise AFR in a diesel like you do a high strung turbo gas engine.

Wide band O2 sensors are unreliably enough that they're kind of a pain to keep working accurately long term if you're not on a racecar maintenance schedule and if you aren't tuning things to those extremes you don't need that level of precision anyway.

Basically it just kinda adds up to "not worth it" for street vehicles


Those people are outnumbered 100:1 by people who simply deleted their trucks when the relevant parts gave them problem and kept the power at stock levels. Those people don't have a reason to brag anything like the "muh 100hp tune" people do so you don't hear about them.


In my final high school years, my parents gifted me a 1980 Corolla, and it became my experimental electronics lab for a while.

I installed a pull-out stereo, a separate amplifier, various permanent and movable speakers, etc. I mostly had the pros installed them, but I was always tweaking things at the wire-harness level. I enjoyed my music EXTRA LOUD, with minimal distortion.

And I had one of those basic aftermarket alarm systems. And there I was, constantly tripping the alarm for various reasons, and we lived in a safe neighborhood, so it was mostly an additional annoyance when I set it off, or armed it, or disarmed it: I was being super ostentatious.

So my proudest DIY mod was to install a shiny toggle switch in the dashboard. The toggle switch had the sole function of disabling the alarm by cutting its power. So I basically handed it to the crooks who came along in a few weeks to steal all my cassettes. But honestly, I doubt that anyone on that block was sorry to see me separated from my music at that point.


Most mods in recent cars seem to just undo some of the regulatory emissions controls in exchange for a bit of performance. Engines aren’t leaving much on the table nowadays. CPU overlocking is going the same way.


It depends on the mod. Some mods are easily an improvement; new tires are probably a good example here, because automakers frequently install crappy tires at the factory because of some sort of deal with the tire company, and worse, replacement for that same model of tire end up being much more expensive than better tires in the same size, probably because many consumers mistakenly think they need the exact same tire.

But yeah, most "enthusiast" mods are a waste of money and make the vehicle worse.


I've been sailing on a 13 meter long boat in 40 knot winds, and that mast looks to have more area than the total sail we had up. The moment the wind imparts on such a tall mast must be massive.


They should make these masts retractable.


That'd only help if they'd retracted it before the storm hit.

Given that they didn't undertake other, "lesser" preparations before the storm hit...


Eh, there's some nuance there; the shipbuilder claims they didn't properly prepare and the crew say they did prepare. The limited evidence so far seems to side with the crew.


Old wooden sailing ships had masts that were somewhat retractable in that the upper spars could be removed and taken down on deck. But this isn't really practical with modern aluminum or carbon fiber masts. And it would complicate the rigging.


If you have an axe on board, all wooden masts are retractable in an emergency.

Or use a kite.


I searched the interwebs for what 'lufting' is and found nada.

The term is luffing for anyone who wants to look further into these things (as I do/did).


Broke boats and airplane owners club advertising?


People have been successfully modifying vessels to better fit their uses for thousands and thousands of years. This wasn't even modified after delivery. It was built to order this way by the OEM. Everything has tradeoffs. Sometimes people go too far or choose the wrong attributes. You're making a mountain out of a mole hill.


People have not been making vessels with 237ft masts for thousands of years. That boat literally had one of the tallest mast ever to exist on a boat. You combine the “extreme” nature of this boat with an extreme weather event and you get an extremely outlier outcome


I did some resarch because i didnt believe your comment at first.

It seems true, the preussen had a similiar height and was a really big ship.

https://en.wikipedia.org/wiki/Preussen_(ship)

It shows how utterly insane the design of the bayesian was.


Materials science has advanced quite a bit since the Preussen though. Aluminum, or even carbon fiber masts, rod standing rigging, Dyneema (UHMWPE) ropes, etc., all add up and drastically reduces weight.

Not saying the Bayesian design was or wasn't insane, I don't know, but my point is that it shouldn't be judged compared to what was done over 100 years ago.


It's only ~10% taller than the top end of stuff that was cranked out for commercial use 150yr ago. Forgive me for being unimpressed.

https://en.wikipedia.org/wiki/Great_Republic_(1853_clipper)

Yes, the yacht is a much smaller ship but it has half as many masts it's masts are aluminum, it has engines so it doesn't have to run sail in poor conditions to maintain control authority and benefits from 150yr of improvements to watertightness.

I get that everyone wants to act smug because "everybody knows that you don't put big weight high up, hehehe, stupid billionares" but I'm betting that when the dust settles, the circle jerking dies down and the reports get published the end result will be the mast being a contributory factor (I'm betting on the reduction in righting moment rather than wind area) at best and that the outcome would not have been that much more unavoidable had the same other currently unknown errors been made on the other ships of the class.

A modern ship in good state doesn't just sink in minutes from capsizing. Other stuff had to have gone wrong here too. These vessels are designed that you can spend all day burying the bow in wave after wave. A little dip of one gunnel into the water should not be catastrophic. TFA discusses this.


Ok true but that boat was much much heavier and bigger. So the ratio of mast height to weight/size on the Bayesian was extreme

Having a home designed (previous owner) world sailing vessel with a mast that is bigger then the original designer's spec. It made it around cape horn and has seen a lot of high latitude low atmospheric pressure no problem. I've heard it argued that a longer mast makes the boat more stable like a tightrope walker with a pole.

I'm curious about how it went for you?


Not GP or mech eng, but I suspect something similar to the following:

Sail area ~square mast height Mast wind force under sail ~linear sail area Mast diameter ~square mast wind force under sail Mast wind force reefed ~linear mast diameter

If that's right, then you're in quadratic shit. How much bigger was the mast, a metre taller or - like the Bayesian - tens of metres?


it's probably futile, and the 'AI/art protests' seem to miss the point that the protest itself is also encouraging The Man to seriously consider AI-powered replacement.

The protest itself is exactly the kind of thing that will be avoided by replacing humans, demonstrated writ-large for the people with the cheque-book.

I can understand the spirit of protest and why it occurs, but it just seems so out-of-line strategically/tactically when used against automation that's taking jobs.

Just the order of events is kind of funny to me, and this applies to automation-job-taking protest the world over : A technique is demonstrated that displaces workers, the workers then picket and refuse to work -- understandable, but faced with the current prospect of "This mechanism performs similar work for cheaper", it seems counter-productive to then demonstrate the worst-case-scenario for the patron : a work stoppage that an automated workforce would never experience, alongside legal fees that would never be encountered had they an automated work-force.

That all said, protest is one of the only weapons in the arsenal of the working -- it just feels as if the argument against automation is one of the places where that technique rings hollow.

In the case of media/movies/literature/etc, I think the power to force corporations to value humans is solely in the hands of the consumer -- and unfortunately that's such an unorganized 'group' that it's unlikely they will establish any kind of collective action that would instantiate change.


>"New: Retargeting for testicles."

someone in a long past IRC said once that all the (visual) details in a human is in their fingerprints and their ballbags, everything else is generic.

I don't do vfx really, so I can't speak to the truth of that :

/s but at least it sounds like we're automating the hard work for our VFX colleagues. /s


>You can overlap this so the engine continously delivers torque to the wheels. Thus, no head bobbing.

head bobbing (sudden g-force jerks) was fixed before the introduction of another clutch; that's a function of rev-matching between upshifts and downshifts. An early BMW SMG system, a manual gearbox with electro-hydraulics on top of it to handle shifting and clutch work, gets rid of the head bobbing.

How? Precise rev-matching.

dual clutch systems were a means to speed the gear-shift process up, with two clutches there is no need to wait for shaft speed mismatches, you just keep the opposite clutch where you need it RPM-wise. This helps alleviate the head-bobbing, but it's more just an artifact of how the system has to work -- rev-matching is now something required in order not to blow the system up.

tl;dr : it's the rev-matching saving your neck, just like it would've been doing had you been a passenger with a race driver -- but they're doing it to save tires and keep the car stable, they probably don't care about your neck.


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