Friday, April 30, 2021

Sometime in the Next Year

Everybody knows the story behind the attempt at humor.  It prompted a long research project by Mrs. Graybeard into whether "those" is the proper word or whether it should be "are they menthols?"  And a nearly half hour long attempt on my part to remove the apostrophe in "menthol's."  It's not referring to something in the possessive.  It's not the menthol's cigarettes.  

Thursday, April 29, 2021

SLS Core Stage Now In the VAB on the Kennedy Space Center

The SLS core stage was shipped (literally, by barge) from the Stennis Space Center to the Kennedy Space Center here in Florida this week.  The barge arrived in Florida on the 27th, traveling to the turning basin in front of the Vehicle Assembly Building.  Transfer to inside the VAB was accomplished this afternoon.  At this point, it's now being referred to as the core of Artemis 1: the first, unmanned mission the SLS will fly.   

Teams from the center’s Exploration Ground Systems and contractor Jacobs will perform checkouts ahead of integrating the massive rocket stage with the twin solid rocket boosters, Orion spacecraft, and additional flight hardware ahead of the Artemis I launch.

Artemis I will be the first integrated test of SLS and Orion and will pave the way for landing the first woman and first person of color on the lunar surface. It will be a proving ground for deep space exploration, leading the agency’s efforts under the Artemis program for a sustainable presence on the Moon and preparing for human missions to Mars.
As you would imagine, it's not exactly a trivial exercise to handle something massively heavy yet fragile to loads it wasn't designed for, but that's coming very soon as they need to transfer the core stage to a vertical position for the beginning of the integration process.

The twin solid rocket boosters are completely stacked; that was completed in early March.  Despite their similar appearance to the Space Shuttle Solid Rocket Boosters, they're reported to be the largest and most powerful solid rockets ever made.  Each booster produces 3.6 million pounds of thrust.  An important detail to point out is that, like the Shuttle, those SRBs will support the entire weight of the core stage and everything that's mounted to it.

John Honeycutt, the SLS program manager, said, “with the delivery of the SLS core stage for Artemis I, we have all the parts of the rocket at Kennedy for the first Artemis mission.”  NASA is still aiming for a launch before the end of the year, although they'll openly say that's “challenging.”  The original date published was this coming November, but that was before the test window at Stennis ballooned up to nine months.  To have the schedule hammered that badly and not move the launch date out by more than a month would be truly remarkable.  FWIW, I think this goes beyond challenging all the way to improbable.  I wish them luck but I'd be really surprised if this isn't delayed until well into '22.  I think a three month delay into late February/early March would still be remarkably good.

I can't let this column go without noting that part of the quote above made my skin crawl and filled me with dread.  “Artemis I will .... pave the way for landing the first woman and first person of color on the lunar surface.”  So the goal of the Artemis program is to send identity politics into the universe?  If there's anything about humanity that deserves to die off on earth and not spread it's identity politics.  It was bad enough when they said Artemis was to land the first woman and the next man on the moon, but that's apparently too mild today. 

I think I've been clear that I think SLS has been a horrendously bad waste of money.  The decision to kill a program after so much has been spent on it is a tough one for a politician to make.  They're subject to the sunk cost fallacy over things like this.  They have to admit they threw away billions on something like SLS and never got anything for it.  

Wednesday, April 28, 2021

Farewell and RIP Michael Collins

Since I ran across this meme a couple of years ago, it has come up whenever references to Michael Collins, pilot of the Apollo 11 Command Module, as being the "loneliest man in history" come up.  I think it's sobering to add three words to the meme.  "Michael Collins is the only human, living or dead, in human history not contained in the frame of this picture."

We learned that Michael Collins died earlier today after battling cancer.  He was 90 years old.  

"He spent his final days peacefully, with his family by his side," the family said in a statement. "Mike always faced the challenges of life with grace and humility, and faced this, his final challenge, in the same way. We will miss him terribly."

With Collins' death, only 10 of the 24 humans who have flown into deep space remain alive: Collins' colleague on the Apollo 11 mission, Buzz Aldrin, as well as Bill Anders, Frank Borman, Charlie Duke, Fred Haise, Jim Lovell, Ken Mattingly, Harrison Schmitt, David Scott, and Tom Stafford.

Eric Berger, space columnist at Ars Technica, has a good biography posted.  After some details of his time in NASA, he concludes this way.

After this historic flight, Armstrong became famous as the first human to walk on the Moon. He bore it with dignity and quietly retreated from public life to work as a professor at the University of Cincinnati. He died in 2012 at the age of 82. Aldrin has lived a more public life, battling alcoholism but emerging as a cultural hero and living icon of the Moon program.

By contrast, Collins went on to a career of service, working as director of the National Air and Space Museum as well as other positions. He was a sober and intellectual figure after the Moon landing and was the poet of the mission, writing perhaps the finest astronaut autobiography of the Apollo age, Carrying the Fire: An Astronaut's Journeys. For anyone interested in a true accounting of what life was like as an astronaut (and watching two friends go down to the Moon), this book is essential reading.

Collins retired as an astronaut after the Apollo 11 mission and, in doing so, turned down a chance to go down to the lunar surface himself. According to Slayton, Collins was his first choice to serve as commander of Apollo 17, which would become the final mission to the Moon. This was even before the launch of Apollo 11. Collins replied by thanking Slayton for the offer but said he had grown tired of the grind, and if Apollo 11 went well he was planning to step aside. Collins has now finally found a deserved and eternal rest.

In 1994, Mrs. Graybeard was working as a technician on the Space Shuttle Solid Rocket Boosters up on the Cape, and I was working for Southeast Area Defense Contractor doing radio design.  When July approached, the KSC announced there would be a celebration of the 25th anniversary of Apollo 11, and all three astronauts would be there.  Families were invited.  Somewhere around here I have some photographs I took of Armstrong, Aldrin and Collins.  Of course, we just watched from the crowd, which included some of the people who were working various jobs in support of Apollo 11.   

When I was younger, I used to wonder how Collins had felt about training all his adulthood for the possibility of going to the moon, and then not landing and walking around.  Later, I came to think he was doing his job, just like Neil Armstrong and Buzz Aldin.  His job was an integral part of theirs.  True, he was closer to the moon than billions of people have ever been, he just wasn't touching it.  As Robert E. Lee famously said, “Do your duty in all things. You cannot do more, you should never wish to do less.”  First and foremost, Michael Collins was doing his duty.

Rest in peace Michael Collins.  The world is a better place for you having passed this way.

Tuesday, April 27, 2021

After Successful Static Test, Elon Says SN15 to Launch “Later This Week”

The headline on Teslarati was "Musk says upgraded SpaceX Starship to launch “later this week” after static fire test" which would imply that they got the results they wanted from last night's static fire.
Starship SN15 static fire completed, preparing for flight later this week
Today, Lab Padre said SpaceX had issued another over-pressure notice.  The road closure was on and off from 12 Noon to 8PM CDT and it was hard to see if they were going to do a static firing until well after 7PM Eastern.  It was 6:48:47 PM CDT and 7:48 here.  

The commentators on the channel said they had looked at different cameras carefully and are convinced this is a single Raptor firing.  The speculate the reason is that yesterday they tested all three engines with the main tanks while this evening's test was to test one engine with the header tanks.  Those are the two small tanks that hold the fuel and oxidizer for landing.  The LOX tank is at the very nose of the Starship while the methane tank is actually inside the main methane tank, much closer to the engines. 

To put it in perspective, serial numbers 8 through 11 flew between December 2020 and April 2021.  All four failed to complete the tricky maneuver of falling belly first, flipping vertically, lighting two engines and coming to a soft landing.  SN10 landed successfully, but it was a hard landing, collapsing legs.  10 minutes later one tank exploded destroying the vehicle. Lifting a good summary from Eric Ralph at Teslarati:
All four failures ultimately had different causes. Starship SN8 lost fuel tank pressure, starving its Raptors and causing a near-total loss of thrust seconds before touchdown. One of SN9’s Raptors failed to ignite for a landing burn, triggering an even more aggressive impact with the ground. Starship SN10 landed in one piece but its lone landing engine underperformed when it began to ingest helium ullage gas – a quick-fix implemented after SN8’s pressurization issue. SN11 exploded almost immediately after attempting to ignite its three engines for landing, failing even earlier than its predecessors.

All four flight tests saw each respective Starship prototypes narrowly miss a fully successful and survivable landing, providing SpaceX a great deal of data and direct experience to improve the rocket’s design and operations with. Two of the four failures – SN9 and SN11 – appear to have been the fault of one or more of Starship’s three Raptor engines. Beginning with Starship SN15, SpaceX has moved to an upgraded iteration of the next-generation engine, raising hopes that whatever changes the company has implemented will substantially improve reliability and thus the odds of a successful high-altitude launch and landing test.
What does "later this week" mean?  Weather-wise, it looks like Thursday might be the best day, by the Weather Underground forecast.  Friday looks to be cloudy all day with some thunderstorms around all day.  Thursday looks to have lower chance of rain, and clouds clearing out by the late afternoon to evening. 

Monday, April 26, 2021

Monday Got Away From Me

I started down the road on a post but it's just not writing itself.  

Six years ago, I had called Obama's EPA the High Priests of Junk Science.  Biden's EPA - or whoever is driving this driving this New Green Deal agenda is even worse.  Stuff like saying they're going to force us to eat no more than four pounds of beef a year.  I've met people who will eat four pounds in no more than two days.  Their health deteriorates if they don't.  If the administration's intent is to kill off Americans, like we just talked about, that's the only thing that makes sense.

Well, at least we got to see a static firing of SN15 this afternoon, a minute or three before 6PM EDT.

Sunday, April 25, 2021

Licensed Hams - A New Rule on May 3rd

The American Radio Relay League reminds all amateurs that in case you've missed it, the new RF exposure rules take effect on Monday, May 3rd

The FCC has announced that rule changes detailed in a lengthy 2019 Report and Order governing RF exposure standards go into effect on May 3, 2021. The new rules do not change existing RF exposure (RFE) limits but do require that stations in all services, including amateur radio, be evaluated against existing limits, unless they are exempted. For stations already in place, that evaluation must be completed by May 3, 2023. After May 3 of this year, any new station, or any existing station modified in a way that's likely to change its RFE profile - such as different antenna or placement or greater power - will need to conduct an evaluation by the date of activation or change.

I did a fairly deep dive into the requirements last May, before I had my Ham Radio Series, so they're not on that separate page, but the first part is "A Little Radio Safety Techno-Geekery", and some examples of how to go about the calculations are in the second part, "A Little More on RF Power Safety and Ham Radio."  Besides my writings, the league itself offers things to help you.

"RF Exposure and You" is available in PDF format for free download from ARRL at,
ARRL also has an RF Safety page on its website at,
The ARRL also has a worksheet that helps in the process.

Here's the odd part.  There are no instructions that this is to be filed with the FCC or anyone else.  I suppose that means you're expected to do the calculations, and keep them on file in case you're questioned at some point.  I would presume that would be if a neighbor complains you're interfering with their TV or Stereo or other form of entertainment and an investigation is started.  Thankfully, with the switch to HDTV and cable, those complaints seem to be fewer than back with analog TV.  

As the ARRL points out, the major change in the rules is that before now, hams were generally exempt from this requirement.  That exemption goes away.  

There is no preferred format stated for the analysis, but sticking with that ARRL worksheet might be a good thing. 

As a quick review, let's look at table 1 in the first of my two posts.  This shows the power at the antenna that requires analysis:

If you operate a typical, off the shelf ham transmitter/transceiver with 100 Watts output power, you don't have to address any exposure until you get to the 12m band, because there are unavoidable losses between the output of the transmitter and the antenna, and even tenths of a dB loss will get you below the 100 Watts that requires evaluation on 15m.  

The next table in that article tells you the distances (in meters) from an antenna with one of four gains where the power is expected to exceed the FCC power density limits.  Always use the "Unc." column, for uncontrolled exposure - note those are always farther away, which means lower power.  The "Con" column, controlled exposure, is for people working in the industry, expected to be more aware of the need for caution.

Note that you may reduce power by the transmit duty cycle because these are time averaged powers; the chart says 50% and without lots of effort to measure that, it isn't unrealistic.  Even "full power, full time" modes like RTTY (Radio Teletype) don't turn on the transmitter and leave it on for minutes on end.  The league says to use 40% of power for CW, 20% for SSB with no speech processing, 40% for SSB with heavy speech processing,  You should also reduce the power getting to the antenna by the loss in the transmission line to the antenna. 

If I reduce the 100W power to 85% to account for the transmission line (following the example in the second article) that leaves 85 watts at the antenna.  If I reduce that to 30% for the transmitter duty cycle, it's now at 25.5 Watts, far short of the 75 W that requires analysis by the first table.  Notice that each frequency band calculates the powers for four different antenna gains.  In the very simple cases, say your 12m antenna has 3 dB gain.  That means the distance from the antenna where the power exceeds the safety limit is 3.8 meters, or 12-1/2 feet, in the direction the antenna is pointed.  If nobody is closer than 3.8 meters from the antenna, you're good. 

That's even below the power to the antenna that requires analysis for the 10m band.  

I think that between the various resources I've linked to here, both the ARRL's handouts and my articles, you should have what you need to determine how to do the analysis for your station.  As a general approach, there's nothing wrong with making worst case assumptions.  Saying you're delivering the full 100 Watts to the antenna - or a full 100% duty cycle.  That way you know you're always delivering less power to anyone near the antenna and that they're always safer than the limits. 

Saturday, April 24, 2021

NASA's Getting What It Wanted - Independent, Reliable Access to Space

As we sit here today, the International Space Station has two American spacecraft docked to it.  The last time two manned, American, spacecraft with two separate crews were in space together was the Gemini 6 and 7 mission in 1965.  Today, the crews of the Crew 1 and Crew 2 missions are sharing the (relatively) spacious inside of the ISS. 

Today, we're three months short of the 10th anniversary of the last flight of a Space Shuttle.   NASA had to rely on the Russians for rides to the ISS; who promptly raised prices once they knew they had a captive audience.  Yesterday, SpaceX launched the Crew 2 mission at 5:49 AM local time.  It was the third manned mission that they've launched in under 11 months.  In itself, that's a healthy launch cadence, but since these missions are for months at a time on the ISS, it's likely they won't need to launch much more frequently.  I bet they could if there was a need.
"It took 10 years to get there, to achieve this bold vision for commercial crew," said NASA's acting administrator, Steve Jurczyk, during a news conference after Friday morning's launch. "It’s been amazing what the team has been able to accomplish."

The "team" is a collaboration between engineers at NASA and SpaceX that have worked to develop and certify the Crew Dragon system for human spaceflight for a fixed price of about $55 million per seat. Since 2017, NASA had been paying Russia more than $80 million for an astronaut to ride into orbit.
As I've mentioned before, I've read that back in 2014 when SpaceX was proposing reusable rockets, it was four years before they actually succeeded at recovering a rocket at sea.  NASA told them, in essence, "don't bid that; it's a pipe dream that'll never happen."  Fast forward to Friday morning and the reused Crew Dragon capsule Endeavor was launched on a reused, recovered booster.  In a moment of candor, Elon Musk showed that the progress in their reusable Falcon 9 system is surprising even him.
After the launch, SpaceX founder and Chief Engineer Elon Musk said he felt increasingly confident in the prospects of developing a reusable launch system. "It’s only recently that I feel like full and rapid reusability can be accomplished," he said. "I wasn’t sure for a long time, but I am now."

With the Falcon 9 and Crew Dragon, SpaceX has gotten mostly there. However, the Falcon 9 rocket's upper stage is expended after a launch, and the Dragon capsules undergo significant refurbishment between flights. Musk sees this launch system as an interim stage to full reuse, and SpaceX is still learning lessons. The company has already flown one of its Falcon 9 first stages nine times and will soon fly it a tenth time. The plan is to push the limits of the Falcon 9 with the company's own Starlink missions, Musk said.

"There doesn’t seem to be any obvious limits to the reusability of the vehicle," he said. "We intend to fly the Falcon 9 rocket until we see some kind of failure."
I've worked on designing radio systems for satellites before and it always amazed me to think that the level of screening, testing and documenting the parts is the most stringent of all components.  Then we'd build most rockets, use once and throw away.  I suspect that they're going to find their Falcon 9 boosters will easily exceed the 10 flight milestone.   

Changing perspective wildly, I was able to watch the launch from my back yard as usual, and we were treated to a gorgeous flight, much like the one I wrote about last June.  It looked like a typical night launch until the two stages poked above the day/night terminator at altitude, and suddenly the whole contrail started glowing a bright, light blue.  When the booster cutoff and was jettisoned, the spreading  contrail from the upper stage glowed and I immediately saw the light pulsing stronger and weaker.  Within a few seconds I realized I was seeing the booster guiding itself toward it's eventual landing using its nitrogen thrusters.  Every time the first stage fired them, a spreading arc of white radiated out of it, in whichever direction, also turning light blue.  I got to see the first entry burn, but the landing burn is below the horizon from here.  Photographer Trevor Mahlmann at Ars Technica caught several great photos. 

Here's what you're looking at.  The lowest bright spot is the second stage on the way to orbit.  The bright spot higher in the frame is the booster.  Below it are two spreading lobes of the bright reflection of its thrusters.  Farther out from booster in the upper right is the spreading arc of a slightly earlier firing of the thrusters. 

Friday, April 23, 2021

Earth Day Addendum for the Climate Change Peeps You Know

We all have those acquaintances or maybe family members that have drunk the Kool-Aid about a Climate Catastrophe. The ones who seriously believe the nonsense that it's a critical, problem and the world is going to end in 10 years or whatever we're down to.  Admittedly, most True Believers aren't going to believe what I'm going to show you.  There might, however, be people you talk with who are more data-driven and this will be like putting a pebble in their mental shoe.  They'll have to pay attention to it.

This graphic is from Dr. Roy Spencer, posted at Watts Up With That and at his own blog.  For those who don't know Dr. Spencer, here's his bio page.  What this shows is the predicted sea surface temperature trends predicted by 13 different CMIP6 climate models that were run 68 different times.  Those are plots in the various colors, behind the bolder, black line.  The black line is 42 years of measured data from the National Oceanographic and Atmospheric Administration (NOAA).  Clearly, for most of the plots, starting around 1992, the CMIP6 models dramatically over predict the temperature rise.

If you're not familiar with this sort of plot, the Y-axis is the temperature anomaly, stated as the difference between the 1979-1983 average and the measured or predicted data, plotted per year.  Dr. Spencer concludes that the real warming is half of the model predictions, but the model predictions are spread out over a wide band. The latest observation (right end of the black curve) is approximately 0.3C warmer than the 1979 start of these series, while the predictions range from one lower than the measured temperature at 0.1C to 1.5C higher. 

Dr. Spencer is a reasonable scientist, he admits there are things he doesn't know and more.
A related issue is how much the deep oceans are warming. As I have mentioned before, the (inarguable) energy imbalance associated with deep-ocean warming in recent decades is only about 1 part (less than 1 Watt per sq. m) in 300 of the natural energy flows in the climate system.

This is a very tiny energy imbalance in the climate system. We know NONE of the natural energy flows to that level of accuracy.

What that means is that global warming could be mostly natural, and we would not even know it.

I’m not claiming that is the case. I am merely pointing out the level of faith that is involved in the adjustments made to climate models, which necessarily produce warming due to increasing CO2 because those models simply assume that there is no other source of warming.
That's the big issue we're facing: the reliance on models that don't match measured data and a reluctance to actually do the work to test a model.  The data is often hard to measure and truly global.  Just what does global average temperature even mean and how can it possibly be measured with the accuracy? 

Last words to Dr. Spencer:
Why does it matter?

It matters because there is no Climate Crisis. There is no Climate Emergency.

Yes, irregular warming is occurring. Yes, it is at least partly due to human greenhouse gas emissions. But seldom are the benefits of a somewhat warmer climate system mentioned, or the benefits of more CO2 in the atmosphere (which is required for life on Earth to exist).
There's no reason to spend trillions of dollars on the climate.  That will create real suffering and buy nothing good.

Thursday, April 22, 2021

Earth Day 2021

As befitting the environmental movement, my tribute to Earth Day is both late and nearly 50% recycled.  The only way it could fit the environmental movement better would be if everything I said was factually wrong.  No can do.  It wouldn't be me. 

Earth Day, as most of you know, is a holiday made up in the late 1960s at the start of the national environmental movement.  Ira Einhorn is one of the main founders of Earth Day, if not the guy who started it.  Ira practiced what he preached: he murdered his girlfriend (less stress on the planet) and composted her body in his closet.  (Hey - reduce, re-use, recycle!)

You won't find Ira Einhorn's name listed in any of the Earth Day promotional literature, as the organizers have taken great pains to distance themselves from this man, at least since he became better known for composting his girlfriend in a trunk in his closet for a couple of years in the late 1970s.

I was a science geek in high school in 1970, the first Earth Day, and indoctrinated into the liberal crap of the day.  Who can forget the commercial with the crying Indian ("Iron Eyes Cody", who - BTW - was Italian, not Native American) looking at the spoiled earth?  Caught up in the spirit of the day, we went looking for pollution, and tested a local canal for coliform bacteria.   

The movement led to the creation of the Environmental Protection Agency, probably the best example of an agency that has outlived its usefulness.  Unlike government agencies, manufacturing companies are seriously interested in solving problems.  Quality Engineers, Manufacturing Engineers and many others have settled on the Pareto Principle.

Vilfredo Pareto was an Italian engineer who turned his mathematical skills to economic problems.  What he is best known for is the "80-20 Rule", the observation that 20% of the efforts produces 80% of the results.  Although it's an approximation, the rule is more or less right far more often than it is wrong.  Often called Pareto efficiency or Pareto Optimality, it has appeared in quality control, industrial engineering, and popular books.   

How does this relate to the environment?  Pareto (and most of today's Quality Engineers) would say measure your problems.  Find the 20% of problems that cause 80% of the trouble and work to get rid of them while you let the others sit.  Then you "Lather. Rinse. Repeat."  What tends to happen is that you eliminate, or (at least) reduce the biggest problems and then have another set.  You eventually end up with much fewer problems and production running much smoother.  

If you're a government agency, the last thing you want is to solve problems.  Then you have nothing to do.  This is how you get things like the EPA ruling that Ozone concentrations found naturally in unspoiled national parks are higher than should be allowed

Two big problems come to mind.  The first is that reducing legal ozone levels because it's a component of pollution is like reducing legal oxygen levels because it's a component in seawater and we don't want to breathe seawater.  The second is that the current limit is already just about at the  natural background level of ozone.  In most of the country, it's physically impossible to measure the new limits because the natural background is higher than the level they're imposing! 

Today, President Xo announced a goal of cutting CO2 emissions by 50% by 2030 - a mere nine years.  Even more laughable was the talk by Climate Czar John Kerry in which he said even when we get there, "We still have to suck carbon dioxide out of the atmosphere." One would hope he doesn't mean suck all the carbon dioxide out of the atmosphere.  Yeah, it's a trace gas but even third graders know that it feeds all the plants, and that sucking all the CO2 out of the atmosphere is impossible.  Every living creature on the planet will add back CO2 one breath later.  Plants exhale their CO2 at night. 

The 50% goal, though, doesn't mean compared to today, it means compared to 2005.  In my world, when a politician picks a date like that, I automatically think "they're cherry picking the worst possible date," and sure enough this plot from Statista shows that 2005 was about the peak year of CO2 production in the US, pretty much 6000 mmt (million metric tons) of CO2. 

The last point on the plot is 2020, and at 4,571 mmt, we're already down to 76% of the 2005 levels.  

I honestly don't think it's possible at any reasonable cost.  The EPA says the transportation sector of the economy generates 29% of the so-called greenhouse gasses, so shutting down all transportation wouldn't be enough.  That includes not just cars and planes, the typical examples of pollution, but includes shipping goods around the country.  Replacing gasoline or diesel cars with electric just moves the CO2 production to the "electricity" sector - not counting the massive CO2 production in the "commercial" pie slice to manufacture the electric cars.  It would take reductions in all the sectors on this pie chart, and I just don't think it's there to save without invoking "and then something magical happens" - as Kerry pretty much did.

From the US EPA.

Wednesday, April 21, 2021

ATF Proposed Rulemaking on 80% Firearms Leaked

The Federal Administrative Procedure Act of 1946, require agencies changing Federal laws to go through a process.  That process requires the agency present a Notice of Proposed Rulemaking (NPRM) to anyone interested in the change, allowing 60-90 days for comments.  After some period of reviewing the comments and typically allowing some period for commenters to respond, the agency then announces the ruling and any changes made in a Report and Order.  In today's NSSF Ammoland News, they report on a leaked copy of the draft NPRM for the BATFE's rules for so-called Ghost Guns. The document is on Scribd, can be read from the article or downloaded.

The Ammoland article summarizes it this way:
According to the report, any random part that the user could “readily” convert into a firearm would be subject to ATF regulations. As in the past, the document doesn’t define what the term “readily convertible” means. This term could be that any block of metal could be “readily convertible” into a firearm. In fact, the document shows that the ATF used a court case where it took the user eight hours to covert a kit into a gun. The document does highlight the need for a complete machine shop, and qualified workers to complete a firearm would not fall under the proposed rules.
That last sentence leaves out home hobbyists with a reasonably good shop but with no "qualified workers" working for us, leaving us in limbo.  Many of us could make an AR-15 lower from a hunk of raw aluminum bar, but using metal that's already part way toward a finished receiver, like say, an 80% lower, next year's 50% lower, or a "0%" forging simply means our shops can generate fewer ounces of metal chips and finish faster.  

Inadvertently, the BATFE shows just how small this problem is. 
The document makes claims that in the past four years that so-called “ghost guns” have been used in 325 homicides. Their definition of homicide includes justified killings as in self-defense. It does not separate out murders from the total homicides. Even if all 325 homicides included in the report were murders, this number is incredibly small. There are approximately 17,000 murders per year in the United States and that averages out to 46 murders per day. The reported small number they are trying to tie to so-called “ghost guns” highlights that there is not a problem.
Note that they're claiming 325 homicides in four years.  Out of the 17,000 murders per year, they're worried about 41? 

A website new to me, called The Reload, offers an interesting take that Ammoland doesn't go near.
The document also proposes the creation of a definition for “privately made firearms,” which would apply to any gun without a serial number made by somebody who doesn’t have a federal gun-making license. Making guns at home for personal use with devices like 3D printers will not be affected by the definition. However, any privately made firearm sold to a licensed gun dealer would be required to be permanently marked with a serial number by the dealer before it could be sold.
When I made my AR-15 from an 80% lower, I added a serial number that meant essentially nothing; I just figured it was easier to engrave a number than to explain to a potential Officer Friendly in a traffic stop why my gun didn't have a serial number.

I've downloaded the draft NPRM.  It's likely to change before it's released, and it's 107 pages long so I haven't had the time to read the whole thing yet.  One thing I noticed in the few pages I've read is that they seem to be trying to address that nasty little problem they have that an AR-15 lower doesn't match the legal definition of a receiver they're working to, and has made the BATFE drop cases they've been involved in.  Back to The Reload:
The document also lays out plans to broaden and update the federal definition of firearms receiver to correct a problem with the ATF’s interpretation of the current definition. Courts have begun questioning the ATF’s long-running determination that an AR-15 lower is a receiver despite not including several of the parts required in the current definition. Prosecutors have been forced to drop cases involving the ATF’s determination in recent years.

The ATF admitted in the document that “neither the upper nor the lower portion of a split/multi-piece receiver firearm alone falls within the precise wording of the regulatory definition” but lashed out in the document at the “erroneous district court decisions” that employ a “narrow interpretation” of the definition.
I've got to admit that seeing ATF incensed at courts for reading definitions as they're written brings a little bit of schadenfreude here.

The first video I ever put up on YouTube, one pass around the fire control group pocket in my 80% lower, back in 2010.

The columns are saying that DOJ has until May 8 to publish the NPRM, and then the comment period starts.  It's hard to know just where this is going, but I think that at the very least that building a gun will be made harder.  What they seemed to object to in all their actions against Polymer80 is the convenience factor of the company selling the kit of parts to complete the gun alongside the 80% frame.  Fixtures that help you drill the holes for the trigger and safety, like the one in my video, might be made harder to come by because they add convenience. 

Tuesday, April 20, 2021

SN15 Static Fire Wednesday Afternoon

Probably.  Road closure tomorrow from 12 to 8 PM CDT. 

As recently as this weekend, SpaceX appeared to have plans to static fire Starship SN15 on Monday and launch the rocket within 24 hours – April 20th (4/20).  For reasons never stated, although three Raptor engines were available to install by the end of last week, one, #54, was sent away for some sort of rework (commenters said to the test facility in McGregor, Texas).  Raptor #54 was then installed overnight during the weekend, but Monday's road closure was used to bring the second ground support tank to the new facility they're building. 

The three engines on the way to being installed the first time - SpacePadreIsle photo.  The engine number (54) is barely legible on the top of the engine bell of the engine on the right, but it's pointed at the other engines, not the direction we can read.  The engines reported to be on SN15 now are 54, 61, and 66.  The new version engines start at 54, so these are all the new ones.

Something changed while I was writing this. According to Michael Baylor of, there's a TFR for Friday
Starship SN15:
- Static fire NET Wednesday (4/21)
- Launch NET Friday (4/23)
We'll know more by the time the road is reopened tomorrow night. 

EDIT 4/21/21 8:00PM EDT:  The road closure morphed into two closures, one around noon CDT and one later in the day.  The first was used to move a big crane to the test area; the second was cancelled. 

The situation seems more fluid than usual. To quote Michael Baylor of again:
Latest road closures:
   - Transport Thursday morning
   - Brief test Thursday evening
   - Static fire Friday morning
Followed by:
   Starship SN15's test flight is likely not until mid-next week at the earliest. SpaceX really wants to land this thing. Expect risk reduction testing and possibly multiple static fires as they look to give themselves the best possible shot.

Monday, April 19, 2021

Ingenuity Helicopter Flies on Mars

This morning at 3:46AM PDT, JPL received confirmation that the Ingenuity helicopter successfully lifted off of the surface on Mars, climbed to 3 meters (~10 feet), hovered for 30 seconds and then landed.  This marks the first time any spacecraft mankind has sent to another body in the solar system has conducted a powered flight.  The solar-powered helicopter first became airborne at 3:34 a.m. EDT (12:34 a.m. PDT) – 12:33 Local Mean Solar Time (Mars time) – a time the Ingenuity team determined would have optimal energy and flight conditions. It then descended, touching back down on the surface of Mars after logging a total of 39.1 seconds of flight.

“Ingenuity is the latest in a long and storied tradition of NASA projects achieving a space exploration goal once thought impossible,” said acting NASA Administrator Steve Jurczyk. “The X-15 was a pathfinder for the space shuttle. Mars Pathfinder and its Sojourner rover did the same for three generations of Mars rovers. We don’t know exactly where Ingenuity will lead us, but today’s results indicate the sky – at least on Mars – may not be the limit.”
The flight (and all flights of Ingenuity will share this) was autonomous.  It was piloted by onboard guidance, navigation, and control systems running algorithms developed by the team at JPL. Because of the distance from Earth to Mars, the signal takes around 16 minutes to get here and 16 minutes to get back, making any sort of control from Earth impossible.  Like the landing and its "seven minutes of terror" when the flight can't be observed in real time, Ingenuity's 39 second flight couldn't be observed either.  If the helicopter had tried to fly upside down due to a wiring error like last November's Arianespace Vega, they wouldn't know that until the video from the Perseverance rover arrived at JPL.

Now that it has flown, the Ingenuity team has its work cut out for it.  Ingenuity is currently on the 16th sol, or Martian day, of its 30-sol (31-Earth day) flight test window.  Most of the unscheduled delay is due to the software issue encountered last week.  The team will spend the next three days going over all the collected data and come up with a plan for the second flight, currently set for NET April 22nd.  

Final words to MiMi Aung, project manager of the Ingenuity Mars Helicopter at JPL, in a short talk she gave this morning while the team was seeing the results of the years of work for the first time.  
“We have been thinking for so long about having our Wright brothers moment on Mars, and here it is. We will take a moment to celebrate our success and then take a cue from Orville and Wilbur regarding what to do next. History shows they got back to work – to learn as much as they could about their new aircraft – and so will we.”

Sunday, April 18, 2021

A Little Shop Talk - 3D Printing Internal Features

Within the last couple of weeks, I decided to look into printing internal threads.  The first thing I found is that most people either use threaded inserts or they'll mold a hex-shaped pocket to hold a standard-sized nut that snaps into the pocket.  Still, there are plastics that can be tapped essentially like we'd tap metal.  If I wanted threaded plastic, I could print a cylinder with high enough fill rate that it comes out essentially solid, drill a hole in it and tap it.  Or I could print a cylinder with a hole the diameter of the drill bit that I'd use to prepare aluminum for tapping.  That would eliminate one manual step; why not go one step farther and print the internal threads?  

Right now, the defaults in my slicer software are to print layers 0.2mm thick (just under 0.008"), so think about what the thread would look like sliced like that.  The print head will be moving in or out with respect to the center with every layer, and it's possible there's a discontinuity - a little skip or jag from layer to layer.  That made me think that it would interesting to test this with a thread that's at least 5 or 6 times the layer thickness.  

I figured I'd try to print a 1/4-20 internal thread.  Each turn is .050 and .008" is a bit less than 1/6 of the pitch.  Then I said, "why not print 6-32 thread, too; it doesn't cost that much more".  The distance between thread peaks is 1/32" or .031, so .008 jumps layer to layer are relatively big - 1/4 of the pitch.  The first two threaded parts I got off the printer acted funny.  The holes looked too small and then a screw wouldn't even start.  Eventually I measured the parts and found they were about 2% too small.

These are the first two pieces before removing from the printer.  If you look into the one on the left, the 1/4-20, you can see what looks like a flat on the side of the hole closest to the camera.  Now strain a little and see the same feature on the right.  Look a little closer at the ends on the print bed and you'll see a rim that's wider than the rest of the piece.  I don't really understand that, but that's secondary to them being the wrong size. 

I've built three CNC systems, two mills and a lathe, and the first step before running a program was to calibrate the systems in the motion controller.  You tell it a calculated number of steps per inch, then test how far it goes by putting a dial indicator on the tool and telling it to go 1.000".  For example, if you use a common 200 step per revolution motor, you combine that with the number of turns of the lead screw to move 1.000"; for the .050 inch per turn lead screws on the Sherline, you multiply 200 steps per turn times 20 turns, to get 4000 steps.  When it doesn't go 1.000", you scale your numbers to make it match.  I can find no way of doing that for the printer, so I scaled up my drawings by 2% and reprinted.

That did it.  When I tap a hole in metal, the last steps I take are to get any metal chips from the threading out, and verify it by cleaning out the threads with a screw.  The two parts were tight, but both of them worked fine after I ran a screw through the length of the part, which removed some plastic slivers from the inside.

The trick to this view is the wider rim is at the top.  I started threading from the top end.  For scale, those cylinders are supposed to be exactly 3/8" OD.  Scaling got them closer. 

The word of the day is calibration.  I never really checked anything I've printed so far, but I've noticed that wider area on the bottom (printer bed) before.  The software equivalent to where I did the steps per inch calibration I was describing above is built into the printer. The wider rim doesn't show up in the Cura slicer software I'm using, so some more troubleshooting of just what's going on here is next on the agenda. 

Oh, and it's worth ending on this note. While these would work as plastic standoffs for something like a circuit board in a home project, and they cost about a penny's worth of filament each, I think it would be a better use of resources to buy a bagful of standoffs from some company.  The place for this might well be replacing a standoff in a vintage piece of gear (radio, audio, video...) that broke.  Then design one to match as best you can. 

Saturday, April 17, 2021

A Repost On Agenda 21 or Whatever They're Doing Now

Today, J.KB at Gun Free Zone posted an article on Genghis Khan talking about how Genghis Kahn is being talked about as so good for the environment.  Why?  Because he killed off 40 million people and "scrubbed 700m tonnes of carbon from the atmosphere – roughly the quantity of carbon dioxide generated in a year through global petrol consumption – by allowing previously populated and cultivated land to return to carbon-absorbing forest."  Khan killed a lot of people; 40 million was a substantial percentage of the population then, but he's still a piker compared to Chairman Mao who killed off at least twice that number.  

Then Borepatch ran a post about that with some links to older posts he did talking about the same concepts. 

Which led me back to one of my older posts that I've found myself looking up a few times a year (more, lately).  This is from June of 2011.  With 11 years of content, it's pretty amazing how often I go back to something I researched and posted years ago. This one of the posts I've looked up the most.  (The first short line with two links adds surprisingly little to the story, although the second adds more than the first.)

Let's Tie A Couple of Stories Together - part ii

Let me tie Wednesday and Saturday together.

As I said Wednesday's post, it's all about UN Agenda 21, and allowing the flooding of wide tracts of the US supports that idea.  Trevor Loudon at New Zeal has a great post to help you get up to speed on the UN's Agenda 21.   The implications of this plan make Soylent Green or any of the worst, most dystopian-future movies look like Mary Poppins (the most relentlessly optimistic, happy movie I can think of).  To begin with, let's look at a map.  Trevor has a small version, so I went and found one that's readable if you click on it:

 If this UN plan goes into effect, every area in red will be "forbidden zone" for humans. Every area in yellow will be "highly regulated".  I assume that means you will only be allowed there with permits and strict time limits - not to live there.  Humans will basically be allowed to live only in densely packed urban areas, shown as black dots.  Think all of the worst places in America: Chicago, Detroit, New York, Boston, DC... you get the idea. 

Central to the plan is the idea of being carbon neutral.  That's right, "global warming" or "climate change" or whatever they call it this week, is the basis for mass murder on a scale that Mao, Pol Pot, or Hitler could never aspire to.  You see, to quote from this piece at End of The American Dream, (source missing, 4/14/21) the population must be reduced:

  • CNN Founder Ted Turner: "A total population of 250-300 million people, a 95% decline from present levels, would be ideal."
  • Dave Foreman, Earth First Co-Founder: "My three main goals would be to reduce human population to about 100 million worldwide, destroy the industrial infrastructure and see wilderness, with it’s full complement of species, returning throughout the world."
  • Maurice Strong: "Isn’t the only hope for the planet that the industrialized civilizations collapse? Isn’t it our responsibility to bring that about?"
Gee, the moderate guy only wants to kill off more than 95% of the human race.  See the current world population is around 7 billion people.  For Dave Foreman, 100 million out of 7 billion is 100 out of 7000 or 1.4 %.  At 300 million, Ted Turner would generously let 4.3% live.

Around 20 years ago, I heard that the entire population of the world would fit in Jacksonville, Florida, without resorting to vertical high rise buildings.  It would be austere, but they would fit.  I found the area of the city (885 square miles), ran the calculation, and it worked.  Even today, you still could fit every man woman and child in the world in the area of Jacksonville, but each person would only get 3.5 square feet, so it would pretty much be shoulder to shoulder.  According to the Wiki, the area of the state of Florida is 65,755 square miles.  Given the 7 billion people in the world, if you spread them evenly across the state, every person in the world would get 261.9 square feet.  Not a big room (unless you're in NYC), and small by US standards, but generous compared to much of the world.  Of course, the infrastructure would take room, so you'd probably need to spread them out, but I suspect everyone in the world would fit comfortably in the southeastern US.  And we need to kill off 95% of them because they're taking up too many resources? 
John P. Holdren, Barack Obama's top science advisor, co-authored a textbook entitled "Ecoscience" back in 1977 in which he actually advocated mass sterilization, compulsory abortion, a one world government and a global police force to enforce population control.
source for that and this:
“Indeed, it has been concluded that compulsory population-control laws, even including laws requiring compulsory abortion, could be sustained under the existing Constitution if the population crisis became sufficiently severe to endanger the society.”

So the, acting under the Agenda 21 of the UN, wants to forcibly - at gunpoint, I assume - abort your babies, put sterilants in the drinking water, move you to a city center where you can be stacked up like cord wood, and "live" where every move you make, every thing you eat, every decision you make, is made for you by the state.  If you're one of the few percent who aren't killed off.  All in the name of the skankiest, most corrupt "science" humans have ever put on paper (pretty good summary).   It's pretty damned obvious why they don't want us armed, isn't it? 

Oh - if the idea of fitting the entire population of the world into Florida is shocking, you may want to look at this 2013 post.

Friday, April 16, 2021

NASA Selects SpaceX As Sole Provider for Manned Lunar Lander

Just under a year ago, last April 30th, NASA selected three contractors to begin initial development of lunar landing systems that will take astronauts back to the surface of the Moon by 2024.  The three teams and their contracts were the Blue Origin "National Team" of big names in aerospace with a $579 million dollar contract, Dynetics, a defense contractor with a $253 million contract and SpaceX with a $135 million contract.  That amount is 23% of the Blue Origin team and 53% of the Dynetics contract, so smaller by far than the competitors. 

Today NASA announced that SpaceX is the sole winner of the next phase contract to provide a lunar lander to the Artemis program.  That lander will be a variant of the Starship that we've been watching go through development for over a year.
"We looked at what’s the best value to the government," said Kathy Lueders, chief of the human exploration program for NASA, during a teleconference with reporters on Friday.

NASA said it will award SpaceX $2.89 billion for development of the Starship vehicle and two flights. One of these missions will be an uncrewed flight test of Starship down to the lunar surface and back. The second mission will be a crewed flight—the first one of the Artemis program—down to the Moon.
NASA pointed out several advantages of the Starship; a spacious cabin for astronauts, two airlocks, and ample payload capability to bring large numbers of experiments to the Moon and return samples to Earth.  They also liked innovative design and the fact that the base Starship is being designed to land on Mars, something also in NASA's long range plans.

I suspect that they also liked that SpaceX has plunged ahead on development of the Starship out of their own pockets.  Something about "putting your money where your mouth is" as a sign of commitment.

The news article on Ars Technica (second link) points out something that had gotten past me in the news.
For the current fiscal year, NASA said it needed $3.3 billion in funding to meet the goal of landing humans on the Moon by 2024. Congress provided just $850 million, and as a result, NASA acknowledged that 2024 was no longer a realistic target.

A SpaceX montage from my February post reporting that SpaceX had prototyped the elevator shown on the right. You'll note the Starship on the right isn't painted and has fins - more like SN15 than the painted ship on the left.

The big, fat elephant in the room is that current plans are for NASA to launch astronauts in an Orion capsule on the Space Launch System, but SpaceX has openly talked about launching astronauts to the moon on a Starship lifted by the Heavy booster.  The mission plan is to launch them to low Earth orbit, refuel from another Starship, then go to the moon.  Why couldn't NASA do that?  If NASA is strapped for cash, canceling the SLS seems like low hanging fruit.  It's interesting that NASA is studying the program's affordability and whether or not they should keep funding it.

Congratulations to SpaceX, who coincidentally just ended an effort to raise more funding, having raised $1.16 billion.

Thursday, April 15, 2021

Thursday Miscellaneous

The news about the J&J vaccine causing blood clots in something like six women between 18 and 48 out of close to seven million people vaccinated naturally caught my ear and prompted my inner systems engineer to say something like, "WTF does that mean?" Naturally everywhere you go, you come across people essentially saying, "well, if they're telling you it's six you'd be an idiot to think the real number isn't much more."  That's the kind of thinking that there's just no way to deal with if you want to deal with numbers and risk assessment quantitatively. 

I'm big on evidence; actual data. I live by the axiom that half a measurement is better than none, and it has been in most of my home radio projects over the years. I've improved the test equipment to make the measurements better, but I'm resigned that I won't have the measurement quality I had when I was working with test equipment sent for calibration every six months and that cost well into 5 or 6 figures!

It just leads to some thoughts; thinking about the limits of the situation, better known as "bounding the problem."  Of course, six out of nearly seven million is less than a 1.0 part per million (ppm) risk.  One of those patients died or 0.15ppm.  My first thought is that I wonder how many other drugs out there have a risk of serious side effects that's greater than one part per million?  Second thought, on any given summer day in Florida, your chance of dying by lightning strike is probably greater than 1 ppm.  Maybe that's too me-centered, but I live in Florida.  Third thought: the demographic is odd.  All six were women under 50?  Is that due to something else they had in common or that women are more likely to get clots or just what?  I've known one 21 year old woman who had a nearly fatal blood clot from birth control pills (I was 18 at the time), and I understand it's not an uncommon side effect.  In other words, is this observation even relevant to a post-menopausal woman or any age man?

Back at the end of December, and then again in mid-January, I posted stories that centered on the fact that the FDA has a predictable bias in their decision making.  The stories were both that vaccines were being delayed by the FDA's decision making processes which have a bias toward avoiding what are called Type 1 errors, to approve a bad drug, at likely cost of increasing the number of Type 2 errors, which is failing to approve a good drug.  In the type 1 error, they approve a bad drug and a large number of people are harmed.  Even worse, from the FDA bureaucrat's perspective, is they're more likely to be called in front of an investigation board.  In the type 2 error, they block a good drug and there are people that are harmed as well, but those people are invisible.  "Too bad your relative died because there was no drug for their condition!" 

The question to ask is which decision is best for the largest number of people.  The FDA has shown over and over, for years, their default is to block the probably good drug in an effort to not allow a bad drug on the market. 

My attitude toward the vaccines remains that if you're not in a particular risk group, the risk of the vaccines appears to be the same order of magnitude as the virus itself.  That means your best chance at long lasting immunity to it is by getting infected and surviving.  As always, I'm just some dood on the intertubes and if you're dumb enough to take my advice, there's just no telling what will happen to you!

I have two little pieces of space news to pass on,  First Elon Musk has said their goal is to launch SN15 next week.  That's being taken to mean static firing on Monday, for what it's worth. 

The next manned mission to the ISS leaving from American soil will be the Crew-2 mission, currently planned no earlier than 6:11 am EDT (10:11 UTC) on Thursday, April 22nd.  This mission will be the first time that NASA astronauts have flown on a reused booster.  The Crew Dragon spacecraft itself is the one flown in May of '20 by Bob Behnken and Doug Hurley, so it's reused as well.

Wednesday, April 14, 2021

Sometimes I Come Up Empty Handed

Maybe that's empty headed?

I've been trying to determine why the Mars Ingenuity Helicopter hasn't flown.  For those who haven't followed, on April 9th, Ingenuity was commanded to spin up its rotors as a test before being allowed to fly.  The test didn't pass.  To quote from the JPL Ingenuity Page:

During a high-speed spin test of the rotors on Friday, the command sequence controlling the test ended early due to a “watchdog” timer expiration. This occurred as it was trying to transition the flight computer from ‘Pre-Flight’ to ‘Flight’ mode. The helicopter is safe and healthy and communicated its full telemetry set to Earth.

The watchdog timer oversees the command sequence and alerts the system to any potential issues. It helps the system stay safe by not proceeding if an issue is observed and worked as planned.

The previously announced date it would fly was April 11th, with data from JPL available by the 12th.  I went looking for updates on the 12th and found reports the flight was put off until NET the 14th.  (As always, NET = No Earlier Than).  That's today as I write this. 

There isn't a test flight date I can find on the JPL, just this interesting statement:

The Ingenuity team has identified a software solution for the command sequence issue identified on Sol 49 (April 9) during a planned high-speed spin-up test of the helicopter’s rotors. Over the weekend, the team considered and tested multiple potential solutions to this issue, concluding that minor modification and reinstallation of Ingenuity’s flight control software is the most robust path forward. This software update will modify the process by which the two flight controllers boot up, allowing the hardware and software to safely transition to the flight state. Modifications to the flight software are being independently reviewed and validated today and tomorrow in testbeds at JPL.

They then list the steps in making sure that software is safe to upload to Mars and say:

Once we have passed these milestones, we will prepare Ingenuity for its first flight, which will take several sols, or Mars days. Our best estimate of a targeted flight date is fluid right now, but we are working toward achieving these milestones and will set a flight date next week. We are confident in the team’s ability to work through this challenge and prepare for Ingenuity’s historic first controlled powered flight on another planet.

It's safe to say there won't a flight on the 14th or 15th, and very likely not before the 21st.  

When you consider the years of development of this system, you'd think the software would have been verified to not have hangups like this.  It brings to mind a software error that didn't show up until well into the Space Shuttle program.  During the countdown, ground based computers were to hand over control to the Shuttle's internal computers at T-31 seconds.  Long after I would have expected handshaking problems between the computers to have been verified impossible, a handshaking problem aborted a countdown.  

This may be the same sort of problem.  Despite Software Quality Assurance and testing, modules were aligning in time to work properly, not by design but by pure chance.  

Tuesday, April 13, 2021

The Age of Reusability in Space is Dawning

Yesterday's post was on how SpaceX began the era of reusable boosters and completely upturned the existing paradigm of "use once and dump the rocket" that had been in place almost exclusively since the earliest days of the space program.  The obvious exception is the Space Shuttle, which recovered the orbiter and solid rocket boosters but still never achieved its goals or met the lofty promises it was sold under.  During the selling of the program, it was argued the Shuttles would bring the cost of launch to $25/pound.  They ended up missing that goal by a factor of 1000; that's right, $25,000/pound.

Last February marked the first example of extending the life of a satellite, when Northrup Grumman's Mission Extension Vehicle 1, MEV-1, successfully docked with an Intelsat satellite (IS-901) and brought back into serviceable life.  The spacecraft was launched in 2001 and was pulled from active service in December 2019 as it ran low on fuel.  Operators commanded the satellite to move into a "graveyard orbit" farther out than the unique geostationary space, as is the established way of handling satellites that have outlived their usefulness.  This wasn't refueling on orbit, IS-901 wasn't designed to allow that.  Instead, MEV-1 docked with the "disposed of" satellite and pulled it back down to the geostationary orbit, bringing it back to life.

Last week, a second Northrup Grumman satellite, (MEV-2) slowly approached and captured another Intelsat satellite, 10-02.  Unlike the first operational capture, this satellite was still in service at the time, not in a graveyard orbit, delivering broadband and other media services across Europe, the Middle East, and Africa.  The satellite, though, was running out of the fuel it needs to adjust its orbit periodically.  It was nearing time to push this one into a graveyard orbit. 

This was all planned well in advance, and MEV launched last year.  Like its predecessor, MEV-2 was launched into a lower orbit and slowly moved outward by electric propulsion until reaching it's goal. 
Jean-Luc Froeliger, vice president of space, space systems engineering and operations for Intelsat, said the cost of servicing is far less than the value of five additional years of satellite service. Waiting five years will also allow Intelsat to replace the 10-02 satellite with a more modern, efficient vehicle. "For us, it's win-win," he said during a teleconference with reporters. "This extension for 10-02 is very valuable to us."
Like the mission last year, this isn't refueling the satellite.  When these satellites were launched, the concept of being serviced remotely on orbit didn't exist.  Instead, the MEV docks with the target satellite and forms a single larger satellite.  That arrangement is for the five years mentioned above.  At that time (if still working; if not, sooner), the satellite will be pushed into the higher graveyard orbit.

Northrup Grumman artwork.

The source article on Ars Technica reports that Northrup Grumman is experiencing increased interests from commercial and government satellite owners. Tom Wilson, a vice president at Northrop Grumman and president of its SpaceLogistics subsidiary says interest from various governments is increasing. "We’re on the cusp of some bigger initiatives with them."
In 2024, Northrop plans to launch a "Mission Robotic Vehicle" that can provide basic inspection and repair services and deploy mission extension pods to satellites. After this, the company plans to develop refueling capabilities and debris removal from the vicinity of high-value satellites. Finally, in the 2030s, the company intends to begin in-orbit assembly and manufacturing capabilities.

Monday, April 12, 2021

I Missed an Important Anniversary

It was on one of the news sources I read, Ars Technica, but I didn't read the Rocket Report newsletter until yesterday.  Last Thursday, April 8th, was the five year anniversary of the first time SpaceX successfully landed a booster on a drone ship.  2016.  It's hard to think of any changes that commercial space efforts of the early 21st century has brought that are more important, and as paradigm changing as recovering and reusing boosters has been.  Before that, around '14, when NASA's commercial crew contracts were being considered, NASA said not to bid using recovered boosters.  It's a "pipe dream," "it'll never happen."

Three years ago, in 2018, the leadership of the European Space Agency (ESA) was saying they had no interest in making reusable boosters.  After all, it's a jobs program and why would they cut jobs?
Truthfully, if Europe ever did develop a reusable rocket, one that could fly all the missions in a year, this would be unhelpful politically. What would the engine and booster factories sprinkled across Europe do if they built one rocket and then had 11 months off? The member states value the jobs too much. This is one difference between rocket-by-government and rocket-by-billionaire programs. [Bold added - SiG]
It took less than a year for the ESA to realize their launch business was going to go away and they announced plans to develop a reusable version of their Ariane family, largely copied from the Falcon 9.  As did Russia.  Even China is investigating reusability, copying the grid fins from the Falcon 9.  

Eric Berger, Ars Technica's space correspondent, puts a personal side to the story.  Eric says he was born four months after the final Apollo mission and for years had a profound sense of regret at having been born too late to see the peak of space exploration.  “I lived with that regret for decades—right up until April 8, 2016.”

I was not prepared for the experience of watching a skinny, black-and-white rocket fall out of the sky against the azure backdrop of the Atlantic Ocean and land on a small drone ship. As whitecaps crashed into the side of the boat, it seemed like a portal opening into the future. This breakthrough in rocket technology washed away any regrets I had about missing Apollo. In my mind, landing a Falcon 9 first stage at sea represented an essential step toward reducing the cost of getting people and payloads into space and unlocked a bright spacefaring future.

After nearly a dozen failed attempts, subsequent landings soon filled a SpaceX hangar full of used rockets. This caught some SpaceX engineers off guard. "It even surprised us that we suddenly had ten first stages or something like that," Hans Koenigsmann, one of SpaceX's earliest hires, said a few years afterward. "And we were like, well, we didn't really account for that."

tenths of a second before touchdown - April 8, 2016, SpaceX Photo

A few months before this flight in December of '15, SpaceX successfully landed on Cape Canaveral.  I remember watching that landing online.  Definitely a huge achievement but still much easier than finding a drone barge hundreds of miles out to sea, hundreds of miles from where the booster gets jettisoned, and then landing on it with the ship moving, rising up and down with the waves.  Putting a moving rocket onto the moving drone ship was an enormous accomplishment.

It was also a very necessary accomplishment.  It clearly costs money to send that drone ship out for a recovery, the ships leave a couple of days before the first "No Earlier Than" date and will stay out there for most reschedules.  The booster returns to Port Canaveral around 3 days after the recovery.  Figure you're paying a crew for the tugboats, the drone and everything else.  The trade is that it costs more to not send out the drone but bring the booster back to the Cape.  Orbital mechanics being the cast iron bitch that it is, every pound of fuel needed for the landing is an amount of payload they can't put in orbit.  Downrange landings are pretty much required.  There's more.

Over the course of it's flight the velocity of the rocket changes from pointing upward to pointing horizontally.  It takes tons of propellant to effectively cancel that horizontal motion, turn the rocket around and bring it back to land.  It takes much less fuel to essentially let it fall in a normal parabolic trajectory and land farther out at sea.  If you read the performance data for the rocket, a Falcon 9 rocket that lands on a drone ship can lift about 5.5 tons to geostationary transfer orbit, compared to 3.5 tons for a rocket that lands back at the launch site. Had SpaceX not figured out how to land the Falcon 9 first stage on a drone ship, it would have eliminated about 40 percent of the rocket's lift capability, a huge penalty.

The cost of fuel for a Falcon 9 flight is around $250,000.  At the time of this booster recovery, they were charging $61 million for an F9 launch.  They were going to offer a ride on this booster for $43 million.  Just about 30% cheaper.  It's amortizing the cost over two missions, why not 50% off?   Let's pretend $61 million is the actual cost of the Falcon 9 to be manufactured, and the company wouldn't lose money throwing the rocket away after one and only one launch.  Like every Delta, Atlas, Titan and you name it that has been launched until April of '16.  Now think if they launched that booster 10 times, their immediate goal.  Doesn't that make each launch cost $6.1 million? 

Last words to the April 8, 2016 article about the flight on Ars.
So when the moment came Friday, and the rocket stuck, Musk was ecstatic. He could hardly say what would come next. “We're a little bit like the dog who caught the bus,” Musk said, smiling. “What do we do now?”

Sunday, April 11, 2021

A Ham Radio Series 24 addendum - The Supply is Finished

The power supply I discussed yesterday is finished and working.  I've hung an oscilloscope probe on the 5V output and watched it.  There are some spikes far beyond the frequency response of the regulator, possibly being picked up from the air by the scope probe.  There are no drops of the 5V supply that I can find.    

First, an overall view as it's used.  If you look between the bottom of the aluminum channel and the benchtop, you can see some red spots.  One right below each of the corners and one below the switch in the middle.  In the old days, I would use rubber peel-and-stick feet.  This time I printed 1/2" on a side cubes and glued them to the bottom of the channel with superglue.

And a closeup of the voltage regulator.  I added a fairly big electrolytic capacitor (330uF) on the output pin after this picture just to try to ensure no drops in voltage are an issue. 

That writing near the brass nut is sideways.  The pin closest to this edge is I for the input, not H,and I'm sure you can figure out what the O is for.  There's a ground solder lug under the middle brass nut amid those parts and wires, where the two black wires and capacitors (blue) are grounded.  It was difficult to decide which way to mount the S/S module; this orientation or rotated 180 degrees because there are drawbacks to both orientations.  This one makes the LED close to the body of the S/S module rather difficult to see the way I'm using it.  On the other hand, the spark plug and ground wires are on the right, close to the end of the tray and where they're going.  Closest to the bottom side of the channel on the right is a twisted bundle of red, black and white wires.  The white wire is an input from the engine's points (or Hall Effect sensor) which comes in on the right, too.

Part of the idea of making this project is that it can be moved to another engine and I build it once.  The power switch (middle, front) is in the ON position in these pictures.  An LED to show "power on" might be a good addition.