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Posted by Jack Crossfire | Feb 01, 2019 @ 03:17 AM | 6,802 Views
To the stars (0 min 11 sec)



The engine that's taking us to the stars. At least, seeing it brought more confidence than the last month of layoffs & artwork. They definitely got derailed with the focus on the shiny nose, then the thing getting blown over & a month in launch delays to repair the decoration.


The engine was radically different than any previous design, with a turbopump mounted in line with the combustion chamber. Many pipes had to be very long to do that, but it might be lighter to have the turbopump inject oxygen directly into the combustion chamber. This allows more engines to be packed in a smaller horizontal space.

To make the pipes longer, they had to be very narrow. The Merlin famously uses very narrow pipes & high velocity fluid. They operate right at the limit of how fast a fluid can travel through a pipe.


They could also have the turbine on the very top, driving a fuel pump which forces fuel down into the oxidizer pump, which forces the mixture into the combustion chamber. Oxygen is usually the one they want to minimize contact with.


The powerhead is going to be a deadly stick when swinging from the thrust vectoring. It looks more like a traditional jet engine.
Posted by Jack Crossfire | Jan 30, 2019 @ 09:50 PM | 20,926 Views
APOLLO 11 [Official Trailer] (1 min 53 sec)



Impressive restoration of what they claim to be unseen 65mm film. Pretty sure every 65mm piece of film has been seen. There were other restorations, but nothing this sharp. For All Mankind used Gemini footage as filler. It almost looks computer animated, but it's real. They use still photos that were definitely 70mm.


In 4k, it looks more like 35mm. The trick is 65mm in 1965 was equivalent to 35mm for still photos, since the frames were stacked vertically. Only IMAX stacked frames horizontally. The generation that lived during the IMAX film era would be disappointed by what was called 70mm in 1965.


There were 70mm movies, in those days, but it's almost unheard of for the very best cameras to be applied to a space program. Today, they're only documented by a small number of amateur photographers.
Posted by Jack Crossfire | Jan 22, 2019 @ 01:59 PM | 7,125 Views
https://www.popularmechanics.com/spa...ainless-steel/

Most interesting was the double hull idea & that it was never proposed before, which probably means it was proposed before but didn't work. A lot of money & people were invested in carbon fiber rockets for the last 100 years for stainless steel to be that easy. It's a case where the heavy, expensive carbon fiber could be the tried & true solution while the shiny stainless steel could be the risky solution.


He claimed to be on his own in promoting stainless steel, which revives the ages old debate on whether sole visionary leaders or large teams contribute more to progress. We may never know how much of Apple & SpaceX were really contributed by their sole visionary leaders or their lowly employees.
Posted by Jack Crossfire | Jan 20, 2019 @ 07:58 PM | 7,058 Views
PHX4 Rocket launches to over 200000' attaining the highest amateur two stage flight. (15 min 55 sec)



Took a while to show up in the lion kingdom's gootube recommendations. 46 miles is pretty huge for a private individual working with a few friends & a truck. In 4 miles, he's at the scientific definition of space which is rapidly becoming 50 miles.

Very conspicuous how the rocket was never photographed & the design was never revealed. The internet guessed various commercially available motor sizes. The only design clue is a long ramp for lifting off. He's well within ICBM territory & either didn't want it used by terrorists or was banned by ITAR. The terrorism danger is going to keep amateurs from sharing plans & getting into space for some time.
Posted by Jack Crossfire | Jan 13, 2019 @ 03:23 PM | 7,085 Views
Lions have to remind themselves they've actually seen 2 Apollo capsules & the Apollo program was a bigger childhood fascination than the shuttle. Most humans are lucky if they just saw the Apollo 11 capsule on tour. Lions of course covered a shuttle, too.
Posted by Jack Crossfire | Jan 13, 2019 @ 05:06 AM | 6,950 Views
Intriguing news about a Falcon 1.9 being planned for after the main development of the BFR is done. The Falcon 1.9 would be somewhere between the Falcon 1 & never realized Falcon 5 & provide an alternative to micro launcher startups. They want some amount of it to be reusable, maybe all of it if it uses raptors.


It means they're finding these micro launcher startups really are going to impact their business by filling a niche that the BFR can't: small 1 off satellites going to unique orbits, which can't share a launch with hundreds of other satellites or wait for all the other satellites to be ready. It also means major parts of BFR development could wrap up sooner than we think.

Never Seen Before Concept Designs At SPACEX!!!! (4 min 35 sec)

Posted by Jack Crossfire | Jan 10, 2019 @ 01:51 PM | 6,992 Views
So what happens to Blue Origin now that Jeff & Mac have split?

Technically, if the stock market continued rising, Jeff Bezos could have funded Blue Origin with $1 billion every year for the next 136 years. After the divorce, it's optimistically only 68 years. In reality, Seattle's community property law is imaginary. Most divorces end up with an equitable distribution like everyone else.

Based on non monetary contributions to the "community property" like raising kids, managing Jeff's finances, creating an anti bullying organization, Mac will take most of Blue Origin's funding. That could reduce Jeff's nest egg to just $30 billion.

The reality is either the stock market won't keep going up or $1 billion per year won't be enough to fund Blue Origin. It certainly isn't enough to buy 1000 houses anymore like it was 10 years ago. That $1 billion/year pledge was always a tenuous issue.

He certainly didn't plan on spending everything on Blue Origin. Every time he exercised his options, the stock price went down. Then, he's not free to buy anything he wants. If he doesn't invest most of his options in charities, he's gone & he's so far not keen on quitting his job for the cause of space.

The biggest impact will be Mac now owning a majority stake in Blue Origin. She could decide this space stuff is stupid & shut it down or at least slow it way down as Richard Branson did to Virgin Galactic.
Posted by Jack Crossfire | Dec 26, 2018 @ 01:57 AM | 10,437 Views
It burned 330mAh/mile to carry the required batteries & food.
Posted by Jack Crossfire | Dec 25, 2018 @ 02:51 PM | 10,218 Views
How did we end up with old fashioned stainless steel as the ideal material for making spaceships? Most of us older than millenials have lifted pieces of steel. It's very very heavy. Lions 1st encountered stainless steel on boats in the 1970's. Stainless steel became widely available in the 1930's.


Steel represents the reality of how materials engineering experiences 100 year breakthroughs followed by decades of small steps. For interplanetary colonization, we're still limited to the steam boiler technology our ancestors created. The last 100 years of carbon composites created small improvements but just weren't the generational advancement required. Old timers wondered what advancements happened since the X-33 to enable large carbon fiber tanks now & the answer was not really enough. Steel isn't ideal but it's all we have.
Posted by Jack Crossfire | Dec 19, 2018 @ 01:19 PM | 9,805 Views
Boring side wheels (0 min 10 sec)



The lion kingdom gathered individuals weren't allowed to photograph their demo rides through the boring tunnel. The sled idea gave way to retrofitting existing cars with side wheels in front. It sounded rather bumpy, since the side wheels on a monorail are pneumatic, with their own suspension systems. The only video of a real trip was on CBS & like any supposedly autonomous car, it was actually being driven by a hipster who was always kept just out of frame. It was implied that the demo would be some fully automated vision of the future, but reality was more smoke & mirrors.

The side wheels do have some compliance. On the one paw, they avoided the complexity of distributing sleds to all the tunnels. On the other paw, it wouldn't have taken a massive sled to do what the side wheels are doing.
Posted by Jack Crossfire | Dec 15, 2018 @ 04:38 PM | 9,907 Views
For the 1st time, an ESC blew up from getting wet. All 3 PFETs blew up. They had been flown in rain, flown from wet fields, but never blew up before. Dunking in puddles finally got one wet enough to do the job. Potted it in aquarium sealer. It's not reworkable anymore.
Posted by Jack Crossfire | Dec 14, 2018 @ 11:46 PM | 10,037 Views
To make the miles more interesting, the decision was made. Originally wanted to discard the ears & just use the antlers, but didn't have the stomach to tear it all apart, despite being $1. The intact antlers are easier to break down. The nose was an LED light bulb with a red LED replacing the white LEDs. The red LED needed a diffusing cover in the form of translucent heat shrink which is no longer made.
Posted by Jack Crossfire | Nov 03, 2018 @ 05:02 PM | 11,214 Views
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Posted by Jack Crossfire | Oct 17, 2018 @ 10:03 PM | 11,112 Views
https://www.reddit.com/r/spacex/wiki...to_performance


Nifty table of all the SECO orbits. The speed & altitude can be derived from the webcasts, but the inclinations are not broadcast. Not sure how they calculated the inclination change. Even without inclinations, rough calculations based on high school geometry showed it achieving abnormally low orbits. The table confirmed those calculations were right. To recover the booster after launching a 7000kg satellite, it can only reach an elliptical 11000 miles. That's lower than GPS. It's a long way from the direct GEO insertion advertised but never used by the delta IV heavy.
Posted by Jack Crossfire | Oct 15, 2018 @ 03:59 PM | 10,743 Views
Can a PASSENGER land a PLANE? Presented by CAPTAIN JOE (15 min 51 sec)



After months of thinking about the problem, it became clear the passenger should fly manually instead of trying to reconfigure the autopilot as depicted. We're all familiar with the basic airplane controls, have played flight simulators, & can drive cars. Getting the plane to point in a certain heading & controlling speed isn't very hard.


The autopilot is a horribly complex addition. Most of the radio time is spent explaining how to use the autopilot & looking for the controls. She had to lower flaps, lower gear, & reverse thrust, despite the autolanding being engaged. A 2nd passenger could have managed the flaps & gear.
To the lay lion, manually flying would greatly increase the chances of success, but Caption Joe based the video on no doubt what the FAA recommends.
Posted by Jack Crossfire | Oct 13, 2018 @ 01:21 AM | 11,542 Views
Fascinating closeups of the tested fairing half dropped by helicopter. "LATCH +YA2", "PUSHER S/N 6", carbon fiber weaving, nitrogen bottles, are hanging out for all to see. Most important is the "NOT FOR FLIGHT !@%*@! SCRAP" written on a piece, obviously perfected from reviewing many job applications.


https://www.teslarati.com/spacex-mr-...test-practice/
Posted by Jack Crossfire | Oct 11, 2018 @ 12:35 AM | 10,679 Views
Falcon 9 launches & lands behind San Francisco (5 min 34 sec)



The plume had a similar effect as the eclipse in that it was much bigger in the sky than it looked in a photo. The flight went from Salesquota tower to the golden gate bridge. You think these events are tiny dots in the sky when in reality, they seem to take the entire sky up & they're bright. The plume was so big & bright, it felt as significant as the eclipse. Everyone else within view of it must have been as fixated on it as the eclipse.


Hopefully, someday rocket launches will be an hourly occurrence, with the bright plumes a routine sight.
Posted by Jack Crossfire | Oct 04, 2018 @ 01:22 AM | 11,404 Views
New model, showing the latest 10m thrust structure which is as wide as a Saturn V, the paint scheme you'll probably see on the real thing, a 31 engine arrangement, a window configuration which is slightly easier to model than depicted. Never perfect, but always getting better. The wings are bad, but we can see how they would interfere with a gridfin deployment on the pad. Suspected the wings & landing gear would have to be fatter than depicted to support the landing mass.
Posted by Jack Crossfire | Sep 14, 2018 @ 03:07 AM | 10,794 Views
A little more gamma reveals the blended wing body replaced by much simpler beveled wings & canards. The wings & rudder serve as landing gear. Horizontal surfaces are folding, so they can be flat to provide lift, then be a triangle to serve as landing gear. The folding might also provide aileron functionality. There are a lot more windows & they're tinted. The single piece window of BFR 1 returns. The heat shield is a simpler flat shape.

The engines seem to be the scaled down raptors that were tested 1st, but with vacuum nozzles. He decided to reuse the test engine for the upper stage, while reserving the full size engine for the lower stage. It would speed up development to not delay the ship for the full size engine. A bit disturbing to see ablative nozzles.

A bit puzzling how vacuum nozzles would allow landings on 2 different planets with different air pressures. An overexpanded nozzle is too unstable.

They could also be full sized engines with retracting nozzle extensions.
Posted by Jack Crossfire | Sep 14, 2018 @ 03:06 AM | 10,762 Views
Pay $30 for 4 new servos & the old one will start working again.


Anyways, reflowed the QFN's solder joints, & made a servo exerciser to thrash it all night. Naturally, it would never fail on the bench, but the new servos alone stood a good chance of reviving it. The last order of standard servos was 2001. They were $6 Tower Hobby branded, but shipping was much lower. Those hobbyking servos are now $5, but shipping has followed inflation.

Signs started pointing to a glitching battery connector crashing the microcontroller on the servo. The mane CPU also had glitches, but didn't lock up. The servo may just lock up under certain power glitches. After a cleaning, the $60 servo was revived & didn't crash again. So it's a lot more sensitive to electrical noise than a brushed servo. It must run at a much higher clockspeed.