Space X

Stan27 · 30-03-2017 11:07am #1

Huge space x fan.

Launching first reusable first stage tonight. Anyone watching it ?
Will be a live link on the space x website.

Beeker · 30-03-2017 12:26pm

Stan27 wrote: »

Huge space x fan.

Launching first reusable first stage tonight. Anyone watching it ?
Will be a live link on the space x website.

I sure am, you can get good coverage at Spaceflight Now https://spaceflightnow.com/

launch window opens at 23:27 Irish time tonight.

irishgeo · 30-03-2017 10:19pm

Live here https://youtu.be/xsZSXav4wI8

T - 8 mins

domrush · 30-03-2017 10:36pm

Successful landing, fantastic science

domrush · 30-03-2017 10:38pm

Delighted for Elon Musk what a journey

josip · 31-03-2017 10:27am

What I find great about this is that it's not mainstream news and that the successful landing on the barge is a footnote in the Space X release.
While Space will never be easy, some aspects are becoming more routine.

Stan27 · 31-03-2017 5:28pm

Great achievement. The company is only 15 years old, imagine what the next 15 will bring.

ricimaki · 31-03-2017 11:06pm

https://twitter.com/elonmusk/status/847594208219336705

Plans for a re-launch within 24 hours! We could be seeing launches several times a week in the next few years!

Stan27 · 11-04-2017 1:38pm

ricimaki wrote: »

https://twitter.com/elonmusk/status/847594208219336705

Plans for a re-launch within 24 hours! We could be seeing launches several times a week in the next few years!

I presume all the checks will be done by computers, if this will be achievable.

Beeker · 11-04-2017 6:54pm

Stan27 wrote: »

I presume all the checks will be done by computers, if this will be achievable.

They want the booster to be as reliable as an airline requiring only a quick visual check and connect it up to a computer to run a quick diagnostic then refuel and go again.

josip · 17-04-2017 7:17pm

My understanding is that the Falcon 9 will make up the first stage of the Falcon Heavy.

The Falcon 9's final speed before turnaround and re-entry is 1.5km/s and it doesn't get far outside the atmosphere which means that knocking off enough of that speed before re-entry is manageable and viable.

The SLS first stage however has a much higher delta-V and goes further so relanding that is seen a much more difficult proposition and the penalty of the amount of fuel required to slow it down isn't cost effective.

I've just read however that Space X intend to return their Falcon Heavy 2nd stage.

https://techcrunch.com/2017/03/31/spacexs-first-falcon-heavy-launch-could-attempt-upper-stage-recovery/

How can it be a viable proposition for them and not SLS?

Capt'n Midnight · 19-04-2017 8:34pm

josip wrote: »

How can it be a viable proposition for them and not SLS?

SLS is old tech using off the shelf 1970's leftovers from the Shuttle.

The first stage SRB's are cheap and chearful, not worth refurbishing re-manufacturing.

The expensive bits are the engines and turbopumps. Blue Origin is planning to recover just them on it's stages. But on SLS , like the shuttle the engine and fuel tank will be taken to orbital velocity, so a full re-entry would be needed with all the extra weight that would take.

Stan27 · 26-04-2017 7:44am

how far away are blue origin from launching satiates?, or are they concentrating on the tourism sector first, getting people to sub orbit.

Capt'n Midnight · 01-05-2017 5:44pm

Stan27 wrote: »

how far away are blue origin from launching satiates?, or are they concentrating on the tourism sector first, getting people to sub orbit.

If they get the BE-4 engine working then they will have re-invented the wheel. But it needs re-inventing because at present ULA is relying on Russian engines.

https://www.blueorigin.com/be4

The main advantage of Methane is that it doesn't leave residues in the engines, which is handy for reuse. It needs larger tanks so not much better than super chilled kerosene and cyrogenics are way more difficult to handle.

Ignore any waffle about methane self pressurising as you need much stronger tanks which adds weight. Also self pressure means lower engine pressure which translates into lower efficiency. Yes it's good if you want cheap and reliable, especially in orbit when don't have an atmosphere to push against. But not so good when you want extract tax payers dollars.

Capt'n Midnight · 01-05-2017 5:55pm

The higher up you go the thinner the air gets. By the time you reach 100Km an aeroplane would need to travel at orbital velocity to gain enough lift.

So 100Km is the edge of space, if you are travelling at 27,000 Km/hr.

Stan27 · 03-05-2017 8:20pm

So it's expected the the BE-4 engine will out perform both space x's merlin and raptor engines?

Capt'n Midnight · 03-05-2017 8:41pm

Stan27 wrote: »

So it's expected the the BE-4 engine will out perform both space x's merlin and raptor engines?

Depends on what metric you use.

thrust
specific impulse
all up weight , including tankage
cost

And then there's the Total Cost Of Ownership,

IIRC Space-X rocket uses something like $200,000 of propellants. Easy to handle fuel and Liquid Oxygen is something you can order by the truckload, even here. So if they made a rocket that needed twice as much fuel but was a few % cheaper it would probably be worth looking at.

Hmmzis · 10-05-2017 10:31pm

Just a clarification about tank pressurization. There is stored gas type pressurization that is comonly done with highly compressed He in storage tanks on the vehicle. Falcon 9 uses COPV bottles (Compressive Overwrap Pressure Vessel) immersed in the LOX tank to get more He in the same volume. Saturn 5 and Ariane use Ti bottles outside the tanks in the interstage area.
The other is autogenous pressurization where the propellant is used to pressurize the main tank by heating it up in a heat exchanger on the engines producing a hot gas that then gets fed back into the main tank. For both, methane and LOX, there would have to be separate heat exchangers as you do not want to mix hot CH4 with LOX and hot O2 with liquid CH4 (that's better left to the comustion chamber in the engines). This pressure is only high enough to keep the tanks from collapsing and providing enough head pressure for the turbopumps (very important to avoid cavitation). For Falcon 9 that pressure is about 3 bar. The actual pressure for the combustion chamber is provided by the turbopumps, they can go to insane pressures. The Merlin 1D is quite benign at around 97.2 bar, the Space Shuttle Main Engines were a bit toastier at 204 bar. The Raptor is a different beast altogether with the turbos pumping up to a whopping 303.36 bar.

What Captn' Midnight is refering to is pressure fed engine design in rockets. This design is very simple as it avoids all the turbo machinery that makes liquid rocket engines so complex and expensive. The fuel and oxidizer tanks in this design are basically high pressure bottles and the fuel and oxidizer gets fed into the combustion chamber by this pressure alone. It's simple but works only for small rockets and is quite inefficient (high weight for tanks, not that much pressure at all, poor ISP due to ever decreasing chamber pressure).

namloc1980 · 15-05-2017 4:40pm

Launch tonight of Inmarsat 5 F4 at 19.21 EDT (00.21 Irish time). This is the heaviest payload yet for Falcon 9 and therefore no first stage recovery - using the expendable version.

Thargor · 15-05-2017 11:19pm

SpaceX launch in 2 minutes:

Stan27 · 17-05-2017 12:36pm

Thargor wrote: »

SpaceX launch in 2 minutes:

I wonder when the falcon heavy is operational, will a payload like this be done on the heavy, so they can save the boosters, rather than having it expendable.

Thargor · 17-05-2017 6:33pm

Id say thats one of its main selling points.

Imagine when a heavy is launched, we'll be seeing 2 boosters come back and land at Cape Canaveral and the heavy landing on the barge at sea, should be entertaining!

Stan27 · 28-05-2017 10:22am

Thargor wrote: »

Id say thats one of its main selling points.

Imagine when a heavy is launched, we'll be seeing 2 boosters come back and land at Cape Canaveral and the heavy landing on the barge at sea, should be entertaining!

It will be awesome, any idea when a date will be given for its launch ?

namloc1980 · 28-05-2017 12:22pm

Stan27 wrote: »

It will be awesome, any idea when a date will be given for its launch ?

Sept / Oct is the expectation.

The next Spacex resupply mission to the ISS is next Thursday 1st June. Launch at 21.55 Irish time means it may be visible from Ireland about 20 mins after launch as it chases down the ISS in its 51.6 degree orbit.

Beeker · 30-05-2017 7:19am

namloc1980 wrote: »

Sept / Oct is the expectation.

The next Spacex resupply mission to the ISS is next Thursday 1st June. Launch at 21.55 Irish time means it may be visible from Ireland about 20 mins after launch as it chases down the ISS in its 51.6 degree orbit.

That's 2155 UTC so 2255 Irish time

Thargor · 30-05-2017 5:23pm

Anyone know if it will actually be visible?

namloc1980 · 30-05-2017 7:45pm

Thargor wrote: »

Anyone know if it will actually be visible?

Yeah should be visible about 15-20 minutes after launch - weather dependent of course. I remember seeing CRS-6 in 2015. Could easily make out the Dragon, second stage and two payload fairings.

Alcoheda · 30-05-2017 8:32pm

stupid question but which direction do I look and does anyone know how high from the horizon?

Beeker · 01-06-2017 1:09pm

Alcoheda wrote: »

stupid question but which direction do I look and does anyone know how high from the horizon?

If the weather is nice to us and the clouds make way you should see it moving from the west to the east/south east passing almost overhead.

Capt'n Midnight · 01-06-2017 6:14pm

http://www.spacex.com/webcast live in under 3 hours
The instantaneous launch window is on Thursday, June 1 at 5:55 p.m. EDT or 21:55 UTC, with a backup launch opportunity on Saturday, June 3 at 5:07 p.m. EDT or 21:07 UTC

Bonus Flight - 00:45 to 1:45 Irish time.
Ariane Flight VA237 with ViaSat-2 and EUTELSAT 172B
http://www.arianespace.com/mission/ariane-flight-va237/

Capt'n Midnight · 01-06-2017 6:16pm

http://met.ie/latest/rainfall_radar.asp
http://met.ie/forecasts/3hour.asp

namloc1980 · 01-06-2017 9:41pm

Launch scrubbed due to weather. Next opportunity Saturday at 22.07 Irish time.

josip · 01-06-2017 9:44pm

namloc1980 wrote: »

Launch scrubbed due to weather. Next opportunity Saturday at 22.07 Irish time.

They postponed because of the overcast sky over Ireland?

namloc1980 · 01-06-2017 9:48pm

josip wrote: »

They postponed because of the overcast sky over Ireland?

Yeah, sound lads at Spacex.

Capt'n Midnight · 03-06-2017 8:38pm

06/03/2017 21:42

T-minus 25 minutes and counting.

https://spaceflightnow.com/2017/06/01/spacex-crs-11-mission-status-center/

Capt'n Midnight · 03-06-2017 9:03pm

launch now live on http://www.spacex.com/webcast

and it's raining here

refusetolose · 03-06-2017 9:12pm

how long before it pass over?

Capt'n Midnight · 03-06-2017 9:16pm

Touchdown of stage 1

Capt'n Midnight · 03-06-2017 9:17pm

5 mins ?

namloc1980 · 03-06-2017 9:48pm

Didn't see it. Clear sky but think it was still a bit too bright to pick it out.

Beeker · 04-06-2017 7:52am

Beautiful view of it passing over from Waterford. Always a thing of beauty.

padyjoe · 04-06-2017 7:45pm

I've never thought of spotting it in the sky over here. I give it a try next time.

Peregrine · 05-06-2017 1:00pm

ISS capture scheduled for 3 PM.

https://www.nasa.gov/multimedia/nasatv/index.html#public

Stan27 · 09-06-2017 8:11pm

padyjoe wrote: »

I've never thought of spotting it in the sky over here. I give it a try next time.

Neither did I. I thought with the curvature of the earth it would be impossible. The payload usually goes over mid Africa I think

Beeker · 09-06-2017 8:28pm

Stan27 wrote: »

Neither did I. I thought with the curvature of the earth it would be impossible. The payload usually goes over mid Africa I think

It depends on the payload. No launch is visible from Ireland because as you point out the curvature of the earth blocks any view towards Florida, either way the launch itself is well over long before it reaches Ireland. What we see is the payload after separation from the rocket in orbit passing overhead. A lot of the launches from Florida with satellites do head southeast towards the equator so will pass over Africa but payloads for the ISS launch northeast placing the satellite into an orbit that passes over Ireland.

irishgeo · 13-06-2017 8:10pm

Beeker wrote: »

It depends on the payload. No launch is visible from Ireland because as you point out the curvature of the earth blocks any view towards Florida, either way the launch itself is well over long before it reaches Ireland. What we see is the payload after separation from the rocket in orbit passing overhead. A lot of the launches from Florida with satellites do head southeast towards the equator so will pass over Africa but payloads for the ISS launch northeast placing the satellite into an orbit that passes over Ireland.

did we not see the external fuel tank and shuttle over ireland a few years back.

Thargor · 13-06-2017 8:27pm

Yep, we've seen resupply missions chasing the ISS loads of times aswell, it happens.

padyjoe · 23-06-2017 7:01pm

Falcon9 going again in 8 minutes with a comm satellite!

JackieChan · 23-06-2017 7:07pm

Broadcasting live on SpaceX channel on youtube now.

padyjoe · 23-06-2017 7:22pm

Stage 1 has landed on the droneship already. Some achievement. Again. :eek:

Hmmzis · 23-06-2017 9:32pm

That was one toasty landing! Doesn't look they will be able to try out the 'roomba' this time. The engine bells look like almost touching the deck of OCISLY. Can't wait for the on-board footage from the barge to be released.

Next one Sunday from Vandenberg.

Space X

Comments