Lift the Wankel/battery powertrain from a Mazda to use in an airplane?

by philg

Piston-powered airplanes subject pilot and passengers to unpleasant vibration. Battery-electric airplanes have minimal range.

There have been some successful applications of Wankel rotary engines in aircraft. The homebuilt folks have had some success with Mazda RX-7/RX-8 engines. Here’s an article from EAA’s Sport Aviation in 2002:

While incredibly reliable in automotive use, car engines haven’t done well running at high power settings all day every day in airplanes. The aviation-specific rotary engines thus far, such as Diamond’s AE50R, are low power engines designed for self-launching gliders and UAVs.

What if the smooth rotary engine were used to generate electricity buffered through a battery pack? Then it wouldn’t matter if the engine failed more often than 1930s-style Continental and Lycoming piston engines. An engine failure would mean using a 20-minute battery reserve to land. Is there a mass-market low-cost battery+Wankel combination available? Yes! From “The Hybrid Wankel Rotary-Powered Mazda MX-30 R-EV Is Finally Here. Here’s How It Works” (Autopian, January 2023):

For starters, the engine doesn’t drive the wheels. It only serves as a generator connected to a motor/generator unit to send power to the battery pack. The battery pack then provides juice to an electric motor which powers the wheels. This means that despite burning gasoline, the MX-30 R-EV should theoretically have the seamless power delivery of an EV, and it should be able to keep the Wankel engine at its “sweet spot” for efficiency for a significant portion of its on-time.

As for deeper details on that rotary engine, there’s the presence of direct injection, something never attempted before on a production rotary engine. The side housings are aluminum and coated with plasma for low weight and friction management respectively, all while being just 80 mm wide. For the sake of longevity, the apex seals are 25 percent wider than the ones on an RX-8’s RENESIS engine, clocking in at 2.5 mm. The result is 73.7 horsepower from just 830 cc of displacement. Curiously, although rotary engines love to rev, Mazda claims that peak power hits at just 4,700 RPM. That might sound weird for a high-revving Wankel, but it should translate to very low noise.

At 214 pounds, it looks like this engine is fairly heavy for its horsepower (a little heavier than an 80 hp aluminum piston engine), but given the high efficiency of electric drive maybe this would still work out well for a 2-seater.

Readers: Where’s the flaw in this path toward aircraft powered by a mass-market powertrain?

Related:

Full post, including comments

Now that E. Jean Carroll has won $5 million, what stops hundreds of other plaintiffs from mining out Donald Trump?

by philg

New York Democrats opened the hunting season on Donald Trump on November 24, 2022 (CNN describes how the law was changed to open a one-year window with no statute of limitations for sexual assault) and E. Jean Carroll has now won $5 million despite no precise memory of when the life-changing attack occurred and no evidence that she and her defendant were ever in a store at the same time (New York Post).

The judge allowed multiple other survivors to testify about what they suffered at the hands of Donald Trump. What stops additional plaintiffs from coming forward, calling the survivors that E. Jean Carroll called at her trial and also E. Jean Carroll herself, and winning $millions? How tough is it to say “I also was at Bergdorf Goodman at some point in the mid-1990s, plus or minus 5 years, and was attacked by Donald Trump”?

Reid Hoffman, the LinkedIn founder who funded Ms. Carroll’s lawsuit, could himself claim to have been raped, for example. From the NYT:

To make the testimony more credible to a jury of nine Democrats, a plaintiff could assemble some friends and/or family members to testify that the survivor told them about the rape 30 years ago (plus or minus 5 years).

Related:

Full post, including comments

Why can’t San Francisco turn vacant retail and office space into shelters for migrants and the unhoused?

by philg

Headlines are packed with stories about major retailers shutting down stores in San Francisco and distressed office towers. At the same time, we know that folks in the Bay Area are passionate about social justice and welcoming migrants (San Francisco has been a sanctuary city since 1989). See, for example, “Nordstrom is the latest retailer to leave San Francisco” (CNN) and “Office vacancies in San Francisco jump to a record 33%” (The Real Deal).

San Franciscans who say that they want to help the vulnerable and reduce inequality are still wealthy. Why won’t they vote to tax themselves so that the city can acquire the vacant retail and office buildings to turn into housing for migrants and those who are currently suffering from unhoused-ness? These buildings are already equipped with bathrooms and it wouldn’t cost a lot to add more showers. From the WSJ:

Full post, including comments

What will be the origin myths for our current wave of asylum-seekers?

by philg

Signs from Alabama’s Cheaha State Park, within the Talladega National Forest, explaining how Native Americans and Europeans came to be in the area:

“Native Americans were the first people to colonize the Cheaha Mountain area.” and “Europeans left an established life and journeyed across the Atlantic Ocean to pursue their dreams of freedom.”

Native Americans were “colonizers” and Europeans came to the slave state of Alabama because they cherished freedom, not for any economic motivation.

The U.S. already has cities that are more violent, statistically, than the countries from which migrants came here “fleeing violence” (the current origin myth). Suppose that this trend continues (U.S. becoming more violent; countries that enrich us with their surplus population becoming less violent). Will there be a new origin myth for our current wave of migrants? If so, what will it be?

Separately, Cheaha seems like the proper place for the Appalachian Trail (“AT”) to start (story: “The trail was originally imagined as spanning the entire length of the Appalachian Mountains, which would extend it into Alabama, but the Alabama leg never materialized”). As the U.S. population has grown, the AT should grow so that hikers aren’t on top of each other.

Full post, including comments

Small airplanes are super expensive, but still much less useful than pre-coronapanic

by philg

Light airplanes are still at near-historic values, at least in nominal dollars, which seems paradoxical given that their utility for transportation has been greatly reduced by Americans refraining from work. Airplanes, with their 1950s technology and low production numbers, require a lot more labor than our typical mechanical gizmo.

March 31: I have a client in my shop, G6 SR22T, with a cracked cylinder. We’ve been waiting over a month for a cylinder to become available. Does anyone have one?

March 13: Asking for help. Have an aircraft on ground needing a new cylinder. IO-550 2014 SR22T. Does anyone in the metaverse have a cylinder in the real world we can buy? Service center not promising lead time. Thanks

March 17: Grounded 2 months waiting for Line Cutters from Cirrus for my 2010 G3 SR22. Anyone know other sources to get them from? Part #25347-002 [see also “First Engine, Then Parachute Failed In Cirrus Incident” (AVweb, March 30, 2023)

March 28: I’ve owned a Cirrus SR20 (2007 G2) for about a year now and got my ppl and about 200 hours so far. .. In Feb my shop found a crack on the NLG [nose landing gear] strut and ordered a new part for it from cirrus (2-3 month wait), fixing/welding it isn’t an option because Cirrus wont release the engineering drawings. Now, during annual they found NLG puck issues, which are on a 6-8 month back order.

May 1: My Cirrus is based in southwest Florida and was damaged in hurricane Ian inside a hangar. I waited 6 months for Cirrus to come up with an engineering report to tell the service center how to repair the aircraft. Now they are telling me it’s going to take five months to get a new elevator. I could have told them I was going to need a new elevator the day after the hurricane. My Cirrus is going to be out of service for a year. Just wondering how many other pilots are out there who spent a lot of money on a Cirrus and can’t get the company to support the planes already in the field. Seems like all their efforts are in selling new planes and not supporting customers. Right now all I have is a very expensive paperweight.

Separately, here’s something that you don’t want to see during your preflight inspection…. (Pompano Beach, Florida (KPMP), May 3, 2023)

When do people say, “If the airplane is at risk of being grounded for 6-12 months by what used to be a minor problem, I’m not willing to pay $900,000 for a used one, plus $50,000 per year in hangar, insurance, inspections, etc.”?

(Of course, turbine-powered planes always cost a lot to buy and maintain, but the manufacturers were typically fanatical about trying to ensure parts and service availability so as to minimize downtime.)

Full post, including comments

The recent Falcon Heavy launch

by philg

I made it up to Titusville, Florida to watch the 6th Falcon Heavy launch. It was scheduled for a one-hour window starting at 7:29 pm so the Kennedy Space Center folks couldn’t be bothered to stay open and sell $250/person tickets for an up-close view. The wind was gusting to 30 knots all day, but forecast to quiet down around 8 pm and, therefore, SpaceX decided to launch at the very end of the window. A temporary flight restriction went live at 6:54 pm and cuts off a portion of the KTIX airspace, but the airport stays open and all runways are available to VFR pilots (I did not have to demonstrate my ability to land in a 30-knot crosswind, in other words).

Launches can be seen nicely from anywhere along the Intracoastal Waterway (regarding the channel markers: “red right returning doesn’t exactly work until you remember that the waterway goes from New Jersey to Texas and nobody wants to return to New Jersey”–local boat captain). My favorite spots are Shiloh’s, a local steakhouse with a lawn and some balconies, and the Space Bar, on a Marriott rooftop. Shiloh’s will have sports playing on its TVs and sometimes live music while the Space Bar plays the SpaceX YouTube feed (turns out that it is delayed by roughly 30 seconds).

The FBOs at KTIX close by 6 pm and most of the launches seem to be later in the evening. After hours, I prefer to park on the east side of the airport because it is a little closer for Uber so call U.S. Aviation for the gate code to get back in. The terminal will be closed, but there is a bathroom inside the fence for people who arrive after hours. The control tower closes at 9 pm, but there is pilot-controlled lighting, of course.

Shiloh’s from September 24, 2022:

Here’s the Space Bar setup:

The lobby and some other areas are fun too:

How did the launch look? I did not attempt to make an official record, since there were so many closer cameras pointed at the event. Here’s an interesting long exposure by Robert Wyman:

What about the sound? We were so far away that it did not hit us until about one minute after launch and was only a low rumble. A rocket launch in a movie theater is a lot more exciting, especially in the sound department. Still, it was fun to be in a crowd of people who appreciate space technology. After the launch, I caught a ride back to the airport with an interesting guy with whom I’d shared a table. He is involved with the training of firefighters to do water rescue. When I got back to Stuart, I found that a guy at APP Jet Center had been able to see the launch without taking more than a few steps outside:

Friends all the way down in Jupiter had also seen it.

Separately, I wonder why this ViaSat 3 system that was the payload makes economic sense. Each satellite supposedly has 1 terabit/second capacity. But how does that compare to the capacity of the entire Starlink system?

Going to Titusville and watching a rocket launch is the Florida $100 hamburger (closer to 1,000 Bidies, of course, when adjusted for inflation).

Related:

Full post, including comments

ChatGPT is almost as bad at home maintenance as I am

by philg

Perhaps of interest to stupid people who have purchased houses instead of renting professionally-maintained apartments…

I asked ChatGPT about a few recent homeowner challenges and it struggled. A few minutes on YouTube and one can learn that the Bosch E25 error code means that something is stuck in the impeller, which is below the filter and accessed via an extra cover. ChatGPT is confused and says it is all about the filter:

Our house in Florida is too humid because the previous owner called in a humidity strike on his own position by installing low-E hurricane glass windows in place of the previous single-pane clear windows. This brought the required A/C tonnage down from 10.5 to 8.5. We now have 12 tons of single-stage A/C in a house that needs only 8.5 tons. This is a classic recipe for high humidity because the system doesn’t run long enough. ChatGPT completely misses the “oversized A/C that is not multi-stage” possibility.

What if you happen to know that the fix is a “communicating” variable-speed condenser?

ChatGPT seems to think that going from 3 wires to 4 is a minor challenge (“slightly more”). I guess the program has never had to rip a house apart. Also, I think that ChatGPT is confidently incorrect. Here’s the latest and greatest Carrier Infinity, which needs… “2 control wires to outdoor unit”:

ChatGPT on indoor air quality:

This is the one that impressed me:

Let’s circle back to appliance repair….

The actual problem with this fridge, according to the service tech, is failed insulation between fridge side and freezer side. This results in frost building up over 3-4 weeks and blocking airflow until a manual defrost (remove everything and turn off for 12+ hours) is performed. ChatGPT got close by suggesting defrost system problems, but that just leads to about $500 of futile defrost system component replacements. (We are about halfway through the one-year wait for a new fridge that we ordered back in early November 2022 (pre-coronapanic, the same size/brand fridge was available in 7-10 days).)

Full post, including comments

Intel or AMD if you’re committed to social justice?

by philg

Now that the GPU shortage is mostly over, friends have been putting together new desktop PCs. They’re not persuaded, apparently, by GPU performance improvements since 2015 (and why not just use motherboard graphics?). Similar to the great Gillette v. Dorco shaving-for-justice inquiry, one question that has arisen is whether a person passionate about social justice should prefer Intel or AMD.

(Apple is, of course, the historical nerd leader in social justice, marketing 2SLGBTQQIA+-themed products in every country where the Rainbow Flag religion is already celebrated (but somehow not in countries where 2SLGBTQQIA+ sexual acts are illegal). Example from 2022:

But suppose that we are Luddites who prefer Windows 11, want to put our filthy SARS-CoV-2-tainted paws on a touch screen, etc. We can’t buy from Apple.)

Intel was celebrating Pride Month 2022:

(Comment from a hater: “But wasn’t pride about non binary?”)

AMD said in 2022 that they want Pride Month to last all year:

The Corporate Equality Index, “the national benchmarking tool on corporate policies, practices and benefits pertinent to lesbian, gay, bisexual, transgender and queer employees,” rated AMD a full 100 in 2022. Intel, however, also rates a full 100 and goes one step beyond by being a “National Corporate Partner, Platinum”.

AMD’s Diversity, Belonging & Inclusion page says that they discriminate against 73 of the 74 gender IDs recognized by Science. The company wants to advance only those people who identify as “women”:

The company sorts employees by skin color:

How about Intel’s comparable page? They too sort employees by race:

(Note the hateful implication that there are only two gender IDs in the United States.)

Intel also is interested in one out of the 74 gender IDs that Science recognizes:

The company has an “Intel® She Will Connect” web page in which they disclose their passion for discriminating against 73 gender IDs:

Intel adopted the Black Lives Matter religion in 2020 (source):

“Black lives matter. Period,” CEO Bob Swan wrote in a memo to employees Monday, embracing the rallying cry of contemporary civil rights activists. … In his memo, Swan pledged $1 million “in support of efforts to address social injustice and anti-racism across various nonprofits and community organizations.”

Why is it legal to give away shareholder money in this fashion? Mx. Swan earned $67 million in 2019. Why couldn’t he/she/ze/they give his/her/zir/their own $1 million to the Black Lives Matter movement that he/she/ze/they says that he/she/ze/they supports. (Intel’s donations later expanded to about $7 million.)

AMD supposedly promised to give away shareholder money to Black Lives Matter, but it is unclear how much (source).

Readers: What do you think? For folks who are passionate about advancing social justice, which company is better, Intel or AMD?

Also, why do motherboards still generally support only 128 GB of RAM? The MSI X99S SLI Plus motherboard that I got for $180 in 2015 supported 128 GB. Moore’s Law suggests that the correct maximum RAM for a $180 motherboard today is therefore 1 TB (3 doublings, one every two years). Are AMD and Intel so busy at their mostly peaceful BLM protests and Pride parades that they can’t get organized to support more RAM?

(Might there be a substantial market of consumers who want to buy computing hardware, but who don’t agree with the social justice causes that Intel and AMD advance? Drone technology leader DJI does not seem to invest any of the money that they receive in social justice. DJI has never tweeted about Pride Month. What if a Chinese company offered a BLM-, social justice-, and Pride-free personal computer that included an Arm CPU fabbed by TSMC (never tweeted about Pride Month or Black Lives Matter)? There would still be some money going to advance social justice through fees to Microsoft (Windows 11 will run on Arm), but that’s insignificant compared to when a consumer buys a $4,000-$10,000 Intel- or AMD-based PC from a U.S. company. Maybe it wouldn’t have commercial value because too many applications are distributed in X86 binary and would run slower via translation.)

Full post, including comments

60 years of parallel processing

by philg

Based on searching the ACM journal database, the dream of parallel computing seems to date back roughly 60 years. Some folks at Westinghouse in 1962 imagined partial differential equations being solved, satellites being tracked, and other serious problems being attacked.

By 1970, multiple processors were envisioned working together to serve multiple users on a time-sharing system (“A processor allocation method for time-sharing”; Mullery and Driscoll (IBM), in CACM). In 1971, a 4-core machine was set up for keeping U.S. Navy ships out of bad weather: “4-way parallel processor partition of an atmospheric primitive-equation prediction model” (Morenoff, et al.).

What about today? A friend recently spent $3,000 on a CPU. Why did he need 128 threads? “I like to keep a lot of browser windows open and each one is running JavaScript, continuously sending back data to advertisers, etc.”

The benchmark nerds say that you don’t need to spend a lot to maximize single-thread performance:

And you also get pretty close to the best benchmark result with a 550-Bidie CPU:

But maybe the benchmarks don’t fully capture the multi-window browser support capabilities of the $6,000+ CPUs?

Full post, including comments

Carflation Chronicles

by philg

I took our 2.5-year-old Honda Odyssey in for a B127 service, for which I’d made an appointment. Due to the dealer being short-staffed and, apparently, not completely organized, they couldn’t do “7” (brake fluid change) without adding a multi-hour wait on top of the promised 1.5-2-hours.

The parts stock situation has improved compared to 1.5 years ago in that they had all three wiper blades available for the minivan compared to just one back in 2021. The car stock situation is also slightly improved, with a handful of new cars in stock and available at $2,000 over retail. It was $5,000 over in 2022, but of course the total price in nominal dollars is similar because Honda has raised the list price. The identical minivan that we leased in 2021 for $400/month is available… for $800/month. Here’s a 2008 jalopy that, pre-coronapanic, the dealer would have sent to auction (the venerable Ford Taurus sits amidst the parking spaces that in 2019 were jammed with new cars):

Fresh from a checkup with one of America’s 190 board-certified veterinary dentists, Mindy the Crippler was my companion for the two-hour wait and made a lot of new friends inside the dealership. I left her with another customer while I went to get coffee and returned to find that the invasive species had invaded the vinyl seats:

My question for today is how consumers are able to keep spending like drug dealers and/or alimony plaintiffs. A lease quote is the best indication of the true cost of car ownership because it factors in the time value of money and the market’s expectation of depreciation. The cost of car ownership gone up dramatically doubled for anyone who needed to buy a car in the past two years or so, especially when you factor in higher gasoline prices. Therefore, these car owners should have less money to spend on rent, TV/phone subscriptions, entertainment, dining out, trinkets, etc.

What’s new in the Honda minivan world, aside from nothing? Honda seems to have dropped their basic trim level. For Corvette enthusiasts, there is a new “Sport” trim level that has black wheels:

What do readers think? To me, it looks like an old Dodge Caravan whose wheel covers were boosted in the Bronx.

Wikipedia says that pre-coronapanic production of this car was 100,000-130,000 per year between 2009 and 2019. For 2020, however, production fell to 83,000. In 2021, production was down to 76,000. In 2022, it fewer than 48,000 Odysseys were made. Half as many cars at 10X the total profit for manufacturer and dealer? Do we suspect a continued chip shortage or quiet collusion among the handful of major car manufacturers?

If integrated circuits were primarily made in the U.S., it wouldn’t be surprising to find them still in short supply. After all, quite a few Americans were introduced to the advantages of sitting at home playing Xbox all day and habits, once formed, are tough to break. But the Japanese, Koreans, and Chinese continued to work during coronapanic. Why aren’t these hard-working nations making as many chips as car companies need/want?

Against the collusion hypothesis: if the legacy car companies won’t supply a mass market anymore, that opens the door to infiltration by Tesla, Lucid, and Hyundai/Kia (sort of a legacy car company, but also not exactly mainstream until recently).

Related:

Full post, including comments