OpenLayers 5.3.0 and “SyntaxError: missing : in conditional expression”

Just a PSA for Openstreetmap Openlayers 5.3.0 API users.

The rawgit CDN ol.js file appears to contain a malformed ternary operation that causes browsers to not create the ol object, breaking map programs.

The Firefox web console says:

SyntaxError: missing : in conditional expression ol.js:1:34694

The solution is to switch CDN from rawgit to cdn.jsdelivr.net like this:

https://cdn.jsdelivr.net/gh/openlayers/openlayers.github.io@master/en/v6.3.1/css/ol.css

So definitely test your existing Openlayers code on a current version of Firefox.

There’s only a couple of searchable references starting May, 2020, so it’s something fairly new.

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Very Light Jet (VLJ) Market History to 2020

Like everybody connected to the aviation industry, I watched the Very Light Jet (VLJ) market hype (mostly around Paul Allen’s Eclipse 500,) in 2002 and wondered how the market would shake out. After the Eclipse announcement, around 10 competitors announced they would build a VLJ, too.

VLJ’s are characterized by being lower-cost than other private jets, and being certified for single-pilot (SP) operation. However, “lower-cost” increased from $837,000 in 2002 to $3-$5 million in 2020. The key technology in 2002 was a Wiliams cruise missile engine, but that turned out to be under-powered for the Eclipse back then and the engines were upgraded to P&W. A Williams jet is used in the Cirrus Jet today.)

The Eclipse (twin P&W, 370k, ~$1M, 267 made) company was predicted to fail because of the ultralow pricing and company mfg. inexperience. And it did in 2008, although it shipped a few hundred airframes in various stages of completion. Most of the wealthy individual buyers moved on to the Cessna Mustang (twin P&WC, 340 knots, $3.3M, 469 made), which was much more expensive but had the backing of Cessna/Textron.

What’s interesting is that Eclipse reported a major deal with an air taxi, Day Jet. I was skeptical of the deal at the time, but they did receive about 20 jets and provided service until also failing in 2008, although I wonder about the dispatch rate for a v1 jet.

Besides the Cessna Mustang, another successful jet that eventually emerged was the Cirrus Vision SF50.

The Cirrus Vision SF50 (single Williams, 300 knots, $2.7M, 170 made so far) was certified in 2016 and the shipment volume winner for 2018 and 2019. It and the Embraer Phenom 100 (twin P&WC, 400 knots, $5 million) are the only VLJs currently being made, with the HondaJet available at twice the price ($5.5 million.)

(Note that Cirrus (and most small US airplane companies) are owned by Chinese companies as of 2020.)

On Apr. 18, 2019, an FAA AD was issued after 3 incidents involving AOA sensors were reported. Aerosonic, the AOA supplier, shipped bad units to Cirrus, and the SF50 fleet was grounded until replaced. The effect was the same as the 737 MAX accidents, although Cirrus had a hardware, not a mostly software, problem. It’s interesting that a ferry flight was allowed to repair it.

W: Eclipse 500, Cirrus Vision SF50, Cessna Citation Mustang (Model 510), Honda HA-420 HondaJet, Embraer Phenom 100

Textron Ceases Production of Cessna Citation Mustang

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Software Fix Found For A220 Engine Acoustic Resonance Shutdowns

Very interesting:

“Airbus has determined that acoustic resonance is behind the destruction of four engines on its new A220 airliners in the last couple of years. The company has come up with a software fix for the condition, which caused in-flight shutdowns of the Pratt & Whitney geared turbofan engines on three Swiss flights and one on an Air Baltic aircraft.”

Engine makers commonly use remote telemetry, so I’m a little surprised it took a couple of years to pinpoint that. But I’m sure they’ll be adding acoustic sensors now.

Acoustics are a surprisingly big deal in aerospace. HondaJet’s composite fuselage rang like a bell and even passengers needed headsets, so the new Elite version focused on reducing cabin noise by 3 db (half.)

avweb.com: Software Fix Found For A220 Engine Shutdowns

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Cessna 210 Wing Spar Failure



Cessna T210M Wing Spar Shear between top rivets and lower I-beam Flange Narrowing Point (and Lower Forging Lightening Spotface Indentation.) The white foam may have collected water, aiding corrosion. Photo credit: ATSB. (click image to enlarge)

I’ve read thousands of airplane accident reports, but this is one of the most concerning.

The Cessna 210 (and 177) family has a complex wing design made of aluminum components with around 100 features, mostly rivet holes, that can become stress risers.

Since 2012, several spar cracks have been found, and in 2019, there was a fatal accident in Australia after losing a wing, which is not survivable. (Note that this plane was used for aerial survey grids at 200′ with full fuel plus wing tip fuel tanks and 2 pilots, for as many as 5,000 hours. Two survey planes were operated. It would be fascinating to do a teardown on the other one.)

The fatal 2019 accident in Australia appears to be a combination of corrosion on a rivet hole and metal (aluminum) fatigue, possibly combined with the round shape of the lower spar forging spotface (indentation.) Aluminum can shear instantaneously once a crack forms, though in this case the ATSB suspects previous cracking.



Cessna 210 Wing Lower Spar Forging. Photo credit: tennesseeaircraft.net.


Example of a fail-safe spar with a riveted spar web. This might have arrested the crack, but at the cost of being twice as heavy since both the top and bottom half-spars would need to be capable of carrying the load. And all bets are off with corrosion. Diagram credit: aircraftsystemstech.com.


(In the 1995 Kobe earthquake, some of the freeway supports that failed had a steel jacket around the bottom third of the concrete supports, causing a stress riser in a ring around the support. Japan subsequently updated their building code to do full steel jackets. This spar structure failure appears to be very similar if a forging spotface was involved. Under a sideways load, the weakest part would be at the curved spar cap spotface indentation, acting as a strees riser. Under a vertical load, it would still be the same location, since both the spar caps and forgings narrow in thickness at that point.)

This is a tough one to fix, let alone inspect. The spar and other attachments are no longer made, and even if they were, that’s $86,000 into an old airplane. For these to continue to fly, somebody needs to operate these outside the USA and come up with a “massive spar” modification that’s affordable, if not TSO’ed.

Cessna 210 Spar Links

Wings – Aircraft Structures
federalregister.gov: Airworthiness Directives; Textron Aviation Inc. (Type Certificate Previously Held by Cessna Aircraft Company)
tennesseeaircraft.net: 210 Wing Lower Spar Cap Bulletin Sel-57-01 Revision 1 (2012)
avweb.com: Mask Shortage Results In Cessna 210 Spar AD Extension
generalaviationnews.com: Cessna 210 spar caps subject of new Airworthiness Directive
flyingmag.com: FAA Calls for Cessna 210 Wing Spar Inspections
aopa.org: Cessna 210 owners weigh compliance options for corrosion AD
asrs.arc.nasa.gov: Smoking Rivets
nasa.gov: THE STRENGTH AND STIFFNESS OF SHEAR WEBS WITH AND WITHOUT LIGHTENING HOLES (1945)
W: Spotface
faa.gov: FAA Request for Information on Cessna 201 and 177 Airplanes
pprune.org: Cessna 210 Accident Mt ISA

1995 Kobe Earthquake Freeway Collapse

The Collapse of the Hanshin Expressway (Fukae) Bridge, Kobe 1995: Soil-Foundation-Structure Interaction, Reconstruction, Seismic Isolation
fhwa.dot.gov: Aftermath of The Kobe Earthquake

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Covid-19: Nobody Saw Another Corona Virus Coming?

The frequent excuse for the lack of civil preparedness to the corona virus is, “Nobody saw it coming.”

Well, actually that’s not true:

  1. BlueDot, a news alert service, notified their subscribers on Dec. 30
  2. a Texas grocery store chain with a Director of Emergency Preparedness did:
    Inside the Story of How H-E-B Planned for the Pandemic

  3. Disneyworld Shanghai was closed on Jan. 24

And in the past 20 years, there’s been:

  1. SARS-1 (2002)
  2. H5N1 (2005)
  3. H1N1 (2009)
  4. MERS (2012)
  5. Zika (2015-2016)
  6. SARS-2 (2019)

Chronic epidemics, that especially affect those hospitalized:

  1. MDR-TB
  2. obesity
  3. Ebola (most years)
  4. 18 drug-resistant “hospital” bacteria per CDC

Update 2020-04-24: The Wuhan virus lab published papers on corona virus research, and appears to be source of the pandemic. The research was funded by the US, Australian and Chinese governments. More research is needed to 100% confirm what was transmitted and when, but nobody denies this possibility now. The US DOE LLNL also confirmed this in a report in May, 2020.

politico.com: Inside America’s 2-Decade Failure to Prepare for Coronavirus

A corona patient using a ventilator requires up to 21 days on the machine, unlike non-corona patients, which only need 3-4 days typically. I guess it’s somewhat reasonable to not have enough ventilators on hand for 5x as many patient-days. (Update 2020-04-12: ventilator patients have a 66% to 90% mortality rate, so ventilators were ineffective and a red herring. Cannulas (rubber hose with oxygen bottle) are now recommended as long as possible – until chronic fainting.)

But there should have been a plan on how to make/procure them if needed, since the ventilator inventory count is considered important enough by many countries to be a military secret, including the US.

Some constructive things the USA can do for next time:

  1. study coronavirus (SARS-1 and SARS-2) and understand how to test and cure them
  2. maintain a FEMA/CDC/Whitehouse pandemic department and a pandemic mgmt and communications plan, like we used to do
  3. maintain a stockpile of PPE and ventilators (California’s stockpile was not maintained due to budget cuts)
  4. talk to other countries about how they handled it. China, S. Korea and Singapore did a lot better than Western countries.

Covid-9 Timeline Info (Starting Dec. 1, 2019)

TIMELINE: The Trump Administration’s Decisive Actions To Combat the Coronavirus
WHO.int: Pneumonia of unknown cause – China
CDC.gov: Coronavirus (COVID-19)
nationalreview.com: The Comprehensive Timeline of China’s COVID-19 Lies
Wuhan shrimp seller identified as coronavirus ”patient zero”
COVID-19 twice as contagious as previously thought – CDC study
Why New York has 12 times as many coronavirus deaths as California
AP report claims China knew of pandemic danger in Wuhan even as officials downplayed risk of virus
Antibody tests reveal that coronavirus infections vastly exceed official counts
Corona Virus Outbreak Dashboard
Coronavirus: What did China do about early outbreak?

Ventilators

Mossad officer describes covert global battle to obtain ventilators at all costs
For some survivors, coronavirus complications can last a ‘lifetime’
npr.org: Ventilators Are No Panacea For Critically Ill COVID-19 Patients
cnn.com: Doctor: Splitting a single ventilator only works for some
A Medical Worker Describes Terrifying Lung Failure From COVID-19 — Even in His Young Patients
With ventilators running out, doctors say the machines are overused for Covid-19
marketwatch.com: Why this epidemiologist is more worried about coronavirus than he was a month ago
washingtonpost.com: I spent six days on a ventilator with covid-19. It saved me, but my life is not the same.
apnews.com: Some doctors moving away from ventilators for virus patients”> HN

Tracing Apps

youtube.com: Covid-19 in S. Korea

Aviation During Pandemic

Here’s Why So Many Planes Are Still Flying, Nearly Empty
Coronavirus travel restrictions for visitors to Hawaii in 2020
W: List of busiest airports by passenger traffic

Dashboards

Santa Clara County Coronavirus (COVID-19) Data Dashboard
COVID-19 Dashboard by the Center for Systems Science and Engineering (CSSE) at Johns Hopkins University (JHU)
The Johns Hopkins Coronavirus Dashboard Gets 1.2 Billion Interactions a Day
Our World in Data
Rt Covid-19 Chart by State
NY Regional Monitoring Dashboard

Other News

Suspected SARS virus and flu samples found in luggage: FBI report describes China’s ‘biosecurity risk’
medium.com: What Everyone’s Getting Wrong About the Toilet Paper Shortage
The Coronavirus Called America’s Bluff
‘It’s Just Everywhere Already’: How Delays in Testing Set Back the U.S. Coronavirus Response
Best Evidence Yet that Coronavirus Came from Wuhan BSL-4 Lab
Sweden’s Relaxed Approach to the Coronavirus Could Already Be Backfiring
Here’s What You Do With Two-Thirds of the World’s Jets When They Can’t Fly
The Yeast Supply Chain Can’t Just Activate Itself
Near 90% Mortality Rate in Intubated COVID-19 Patients in NYC
36,000 Missing Deaths: Tracking the True Toll of the Coronavirus Crisis
When SARS-1 Ended
Lab-made? CoV2 genealogy through the lens of gain-of-function research
US government review of first Wuhan repatriation says safety protocols not followed
Antibody study suggests Covid-19 could be far more prevalent in the Bay Area than official numbers suggest
Silent hypoxia: Covid-19 patients who should be gasping for air but aren’t

dailymail.co.uk

Coronavirus has been in California ‘a lot longer than we believed’ with cases as early as DECEMBER
Wuhan lab was performing coronavirus experiments on bats from the caves where the disease is believed to have originated – with a £3m grant from the US

Disney Shanghai

Bob Iger Thought He Was Leaving on Top. Now, He’s Fighting for Disney’s Life
Shanghai Disney shuts to prevent spread of virus

Due to #COVIDー19, all TCP applications will be converted to UDP to avoid handshakes.

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