SpaceX rockets and launches

[Limejuice]

Yikes

That should buff out, right?

 

[StoneRoad]

ouch !

 

[DexterTCN]

Blast off in just over 10 minutes.

 

[Limejuice]

A bit more detail about the mishap. Perhaps they should have used a new capsule. The re-used one looked like it'd been well pounded.

 

[Crispy]

Blast off in just over 10 minutes.

That's an old broadcast, not live

 

[DexterTCN]

That's an old broadcast, not live

oh...I thought 5pm was weird.

 

[HAL9000]

This video is floating around on the intenet

http://digg.com/2019/spacex-capsule-failure-video

it looks suspicious, low quality vid and the capscule is not on the rocket.

 

[ferrelhadley]

The Federal Communications Commission has approved SpaceX’s request to fly a large swath of its future internet-beaming satellites at a lower orbit than originally planned. The approval was a major regulatory hurdle the company needed to clear in order to start launching its first operational satellites from Florida next month.

In November, SpaceX sent a request to the FCC to partially revise plans for the company’s satellite internet constellation, known as Starlink. Under SpaceX’s original agreement with the commission, the company had permission to launch 4,425 Starlink satellites into orbits that ranged between 1,110 to 1,325 kilometers up. But then SpaceX decided it wanted to fly 1,584 of those satellites in different orbits, thanks to what it had learned from its first two test satellites, TinTin A and B. Instead of flying them at 1,150 kilometers, the company now wants to fly them much lower at 550 kilometers.

And now the FCC is on board. “This approval underscores the FCC’s confidence in SpaceX’s plans to deploy its next-generation satellite constellation and connect people around the world with reliable and affordable broadband service,” SpaceX president Gwynne Shotwell said in a statement.

FCC approves SpaceX’s plans to fly internet-beaming satellites in a lower orbit

Couple of points here, this will be a manifest that will likely give them the kind of launch cadence they have sought to justify the refurbishment (and hopes to move to reusable) launch vehicles.
This could be a major threat to the likes of Intelsat, Inmarsat etc.
Is there a big enough market for this service though?
And this could be politically explosive if a covert dish is all you need to get through great firewalls and so on.

 

[Crispy]

Is there a big enough market for this service though?

It will have a lower latency between NYC and LDN than an undersea cable (light moves faster in vacuum than it does in glass). The high speed trading market alone is huge $$$. The general market for internet backhaul is gigantic; if Starlink is competitively priced, it should pick up a big slice of that market too. And then there's all the places in the world with a thirst for data but no cables. A village in the middle of nowhere can now be just as connected as a major city. I suspect the cost of a terminal will be too high for direct-to-consumer services for quite a while.

I also suspect the cost of doing business in China, say, is that all Starlink terminals sold in that market have a backdoor that reports back to the government. The potential profits of serving that market will be far more persuasive than any noble efforts to bring free media to the masses.

 

[editor]

Another success: Used SpaceX Rocket Launches 3 Radarsat Satellites, Aces Foggy Landing

Following a rocket launch, SpaceX has two possible options for recovering boosters: returning to land, using a specially constructed landing pad, or touching down at sea, on the deck of one of the company’s two drone ships. The option the company picks varies between launches, predominantly determined by the rocket's payload.

Coming all the way back to land requires more fuel than landing on a ship at sea, so launches that use lots of propellant during ascent (typically toting very large, very heavy payloads) usually have to land in the ocean. But rockets carrying lighter loads, in particular ones bound for low-Earth orbit, have plenty of fuel left to head back to land.

Today's flight marked the 41st landing for SpaceX out of 72 total launches for the company; only 15 of these touchdowns have been on land. And this is only the second time a rocket has landed on solid ground in California; SpaceX's other ground landings have occurred on Florida's Space Coast, where the company has a pair of launch and landing pads.

But SpaceX has always intended to land rockets back at its Vandenberg facilities, Space Launch Complex 4 (SLC-4 for short). Originally home to Titan missiles, SLC-4 is actually two launch sites in one. Split up into two parts — east and west — SpaceX leases both and uses one for launching and one for landing.

 

[Crispy]

This photo tickled me Stainless steel Starship prototype being polished.

 

[existentialist]

This photo tickled me Stainless steel Starship prototype being polished.
View attachment 174739

I bet that Pride umbrella's pissing off a few politicians

"Eurgh, there's gay all over our spaceship"

 

[Crispy]

Falcon heavy night launch in 25m

 

[a_chap]

Nauseating USAF / DoD advert playing at the mo'

 

[Limejuice]

Nauseating USAF / DoD advert playing at the mo'

Pure hornswoggle, wasn't it?

 

[a_chap]

Damn, the centre core failed to land. Damn close though.

 

[Limejuice]

Damn, the centre core failed to land. Damn close though.

It makes me wonder what that drone ship is made of. They keep dropping (in effect) missiles onto the deck, and the damn thing keeps floating. Perhaps that's what the USAF is testing...

 

[a_chap]

Good grief!

 

[Crispy]

Damn, the centre core failed to land. Damn close though.

Looked to me like they braked too hard. The plume was dead centre on the deck, and then it skewed hard over and the rocket flew away to crash. It's supposed to carefully time the burn such that zero velocity and zero altitude line up. Here's me from 5 years ago so I don't have to type it twice:

That's right. The "easy" way to land a VTVL rocket is to approach zero altitude asymptotically. You slow down gradually until you're "hovering" at zero altitude, with thrust exactly matching the mass of the vehicle. Then you turn the engine off and fall the last few centimeters onto your landing legs.

View attachment 31791

This requires deep throttling of the engine, as the mass of an empty rocket stage tiny compared to a full one. Throttling an engine tends to decrease its efficiency - you get less thrust per kg of fuel burned.

A more fuel efficient trajectory is to use the engine at full power, which slows you down much more quickly. The trick is to time it just right so that altitude and velocity reach zero at exactly the same time. If you keep the engine on like this, the falling rocket will slow, stop on the floor, then rise again. So you turn the engine off at the bottom of the curve.

View attachment 31792

Of course what you don't want to happen is start slowing down too late.

View attachment 31793

Or too soon.

View attachment 31794

Because you don't want to hit the ground, or waste fuel oscillating up and down.

That last graph shows what I think happened. This was such a high-velocity landing that the margin for error was very very small.

 

[Crispy]

All 42 (I think? A shit load, anyway) payloads succesfully deployed, in 4 different orbits. By far the most complex mission they've ever done. Oh, and they caught a fairing half in the net! (on the left)

 

[HAL9000]

A small amount of NTO was driven at high speed through a helium check valve (one that allows gas to flow in just one direction) made from titanium during initialisation of the launch escape system - which is designed to blast the crew free in the event of a rocket failure. This led to structural failure within the valve.

It added: "The reaction between titanium and NTO at high pressure was not expected."

As a result of the explosion, SpaceX has already taken several actions, including the use of components called burst disks instead of check valves. The burst disks seal completely until opened by high pressure. The company believes this will prevent any liquid propellant entering the gaseous pressurisation system.

Where I thought spaceX was particularly bad, was the amount of secrecy. Especially since this was a safety system for human crew.

SpaceX has been criticised for a perceived lack of openness in the wake of the explosion. Jim Bridenstine said there was now a new procedure in place in the event that something similar happens again.

"Within a couple of hours, we're going to do a press conference and get as much information out to the public as soon as possible," he explained.

Have to see if they stick to this policy.

Leaky component led to SpaceX explosion

 

[Crispy]

The criticism was not of secrecy with regards to NASA, but with regards to the public. There were NASA officials in the control room when the explosion happened, and the investigation was a joint endeavour from the start. Note that Boeing also had an "anomoly" with their Starliner capsule recently but we didn't hear anything about that in a press conference.

 

[ferrelhadley]

A dragon capsule to be launched for the third time to the ISS, one of the experiments it carries is to try to grow organs in microgravity.

Experiment Details

It is very early stages but it is pretty interesting research.

 

[Crispy]

Also, fingers crossed, the Starhopper will fly shortly after

 

[Crispy]

If the launch goes off well tonight, there's a very good chance to see Dragon fly over in the UK, seeing as there's not a cloud in the sky. The ISS will go almost directly overhead from West to East at about 23:32 , followed by Dragon about 10 minutes later.

EDIT: The 21:58 pass of ISS was very clear. Should be able to see Dragon with no problem

 

[a_chap]

Dragon launch scrubbed

Next launch window is tomorrow 10:01pm UTC

 

[editor]

SpaceX Starship Prototype Takes 1st Free-Flying Test Hop

 

[MikeMcc]

It's also the first vehicle to fly with a Full-Flow Staged Comustion Cycle engine. The US and Russia developed and ran prototypes but never flew with them.

 

[weltweit]

It's also the first vehicle to fly with a Full-Flow Staged Comustion Cycle engine. The US and Russia developed and ran prototypes but never flew with them.

What is that and how does it work?

 

[existentialist]

What is that and how does it work?

If only there was some way of interconnecting a global network of information stores, and - oh, I don't know - in some way indexing them, so that it was possible to type, say, "Staged combustion cycle engine" into a web page, and find some answers...LMGTFY