Launch News Spacex Falcon9 v1.2 with Eutelsat 117 West B and ABS 2A, 15 Jun 2016

[BrianJ]

From SpaceflightNow
http://spaceflightnow.com/launch-schedule/

Quote:
Falcon 9 • Eutelsat 117 West B & ABS 2A Launch time: 1429-1513 GMT (10:29-11:13 a.m. EDT)
Launch site: SLC-40, Cape Canaveral Air Force Station, Florida
A SpaceX Falcon 9 rocket will launch the Eutelsat 117 West B and ABS 2A communications satellites. Eutelsat 117 West B will provide Latin America with video, data, government, and mobile services for Paris-based Eutelsat. ABS 2A will distribute direct-to-home television, mobile and maritime communications services across Russia, India, the Middle East, Africa, Southeast Asia and the Indian Ocean region for Asia Broadcast Satellite of Bermuda and Hong Kong. Built by Boeing, the satellites will launch in a conjoined configuration and will use all-electric propulsion for orbit-raising.
​

Static fire test was succesful, will attempt 1st stage landing on ASDS:
http://spaceflightnow.com/2016/06/13...lcon-9-flight/
Attached Thumbnails

 

[C3PO]

Delayed to June 15 1429-1513 GMT.

 

[Kyle]

Static fire was completed with no issues. Weather is 80% GO.

---------- Post added at 02:45 PM ---------- Previous post was at 12:11 AM ----------

Launch looked good! Payload made it into orbit! Not sure what happened to the first stage. It appears it landed with fire extending 10-15 feet up the side of the booster before LOS. No call outs for successful landing. Probably a LOV, IMO.

 

[Unstung]

If the drone ship's cameras cut out upon landing, the first stage tends to have exploded.

Elon Musk on Twitter:
"Ascent phase & satellites look good, but booster rocket had a RUD on droneship"
"Looks like thrust was low on 1 of 3 landing engines. High g landings v sensitive to all engines operating at max."

The webcast should become available here:

 

[RGClark]

The LA Times is reporting the landing was unsuccessful:

SpaceX launches two satellites, but drone ship landing is unsuccessful.
http://www.latimes.com/business/la-fi-spacex-launch-20160614-snap-story.html

My opinion, in order to land successfully in a consistent fashion SpaceX will have to give the F9 hovering ability.

Bob Clark

---------- Post added at 11:27 AM ---------- Previous post was at 11:17 AM ----------

Elon Musk Verified account
‏@elonmusk
Looks like thrust was low on 1 of 3 landing engines. High g landings v sensitive to all engines operating at max.
https://twitter.com/elonmusk/status/743097337782763521

High g landings are endemic to a "hover-slam" landing, more commonly referred to as a "suicide-burn", more accurately referred to as "land or slam", since without hovering ability, you only get one chance at it. You either stick the landing on the first try, or you crash and burn.

Bob Clark

 

[Urwumpe]

My opinion, in order to land successfully in a consistent fashion SpaceX will have to give the F9 hovering ability.

 

[Unstung]

I think the solution Elon Musk announced shortly after the crash is better:
"Upgrades underway to enable rocket to compensate for a thrust shortfall on one of the three landing engines. Probably get there end of year."

What SpaceX learns from these crashes are used to make the first stage more robust. I think the company will be able to land rockets reliably using suicide burns. SpaceX just had three successes in a row before this launch, all on the drone ship, including two GTO missions.

 

[Urwumpe]

What SpaceX learns from these crashes are used to make the first stage more robust. I think the company will be able to land rockets reliably using suicide burns. SpaceX just had three successes in a row before this launch, all on the drone ship, including two GTO missions.

I don't think it will ever be easy to land on a droneship, but that does not depend on hover. Even at a weak sea state, the ship will be moving a lot and will make it hard to land soft at all. And you also don't want to land soft - the final decimeters of a soft landing are hardly controllable, if you fail to make full contact before cutting thrust, it will become a disaster, if you bounce too often, the shock absorbers will need a different and much heavier design. The only working way is literally a controlled crash into the droneship. Impact hard once, but only once. Even if you damage parts, that can be cheaply replaced.

 

[Andy44]

Ideally I think you'd want a bigger, steadier platform to land on. Something like an oil rig with pontoon floats that doesn't pitch and roll so much on.

Of course, that's a lot more expensive, and so far they seem to be doing well. This crash sounds like it was an engine problem.

If they were using that engine for hovering, you'd get the same result.

 

[dman]

WHOOPS....!!!

Attention Orbital shoppers, Cleanup on barge........

 

[RisingFury]

Hovering wouldn't work at all. GTO missions are already at the edge of the envelope, so fuel is low. If you hover, that wastes a lot of fuel. The whole point of coming in hard and fast is for the engines to burn at high efficient full thrust, for a shorter time.

They'll get it done. Remember the forecast for this year was ~70% landing success.

 

[Kyle]

And besides, the next flight will be an RTLS to LZ-1, so that has a much higher chance of success.

 

[C3PO]

Hovering wouldn't work at all. GTO missions are already at the edge of the envelope, so fuel is low. If you hover, that wastes a lot of fuel. The whole point of coming in hard and fast is for the engines to burn at high efficient full thrust, for a shorter time.

:thumbup:

I was thinking about Andy44's suggestion to use a decommissioned oil rig to reduce the impact of rough seas. How about going one step further and install a stabilized landing deck? You could even incorporate some deflection during landing to soften the impact. Even small deflections will reduce the forces considerably. Just think about how short the crumple zone of a car is.

This is probably too costly this early in the development of reusability, but once the number of launches goes up, you could use this extra margin to get even closer to the edge of the envelope. This would also allow technicians to board once it's safe to do so and start work on the stage without waiting to reach dry land.

 

[Thunder Chicken]

:thumbup:You could even incorporate some deflection during landing to soften the impact. Even small deflections will reduce the forces considerably. Just think about how short the crumple zone of a car is.

The legs currently are crumple zones, crush cores, for precisely this reason. No matter how precise the control, you still need some margin somewhere. Crush core is cheap - oil rigs are gigabucks.

I didn't see the launch or landing but reports indicate a problem with the engines for this attempt. Their investment in sensors is a great idea, they can diagnose the problems much more readily. They are killing all of the edge cases one by one.

Fly, Crash, Learn, Fly, Crash, Learn, Fly, Fly, Fly....

 

[C3PO]

The legs currently are crumple zones, crush cores, for precisely this reason. No matter how precise the control, you still need some margin somewhere. Crush core is cheap - oil rigs are gigabucks.

I'm aware of the crumple zones in the leg actuators. What I'm talking about is using a landing rig to allow landing in rougher weather. The Atlantic ocean isn't always going to be as "smooth" as it was for the successful landings. I'm talking about using an "active" landing platform to add to the margins of the built-in shock absorbers.

Oil rigs ARE gigabucks, but so is the launch business. Probably closer to terabucks actually. You would need to calculate the cost against the cost of loosing some stages and delays.

 

[Thunder Chicken]

Looks like OCISLY survived. Also looks like an on-target "landing" and perhaps some wreckage still on the deck.

---------- Post added at 10:21 PM ---------- Previous post was at 09:26 PM ----------

Oil rigs ARE gigabucks, but so is the launch business. Probably closer to terabucks actually. You would need to calculate the cost against the cost of loosing some stages and delays.

It's not that easy and the costs are bigger than you imagine, and the benefits less than you would like.

First, jack rigs are out because the required downrange distance puts you well off the continental shelf, so DP rig it must be. DP rigs are still subject to swells, just the longer period ones, so you do get a more stable platform (but not stationary).

Getting DP rigs out to sea is a massive undertaking, and once out they don't generally come back. DP oil rigs have drafts of upwards of 100 ft, which means bringing it to port is out of the question. They can't move on their own outside of station-keeping which means you need one of these to get them in position (another massively costly marine asset):

Also, this means you need to maintain a rig at sea perpetually. Mooring off the continental shelf is a no-go proposition, it's way too deep. This would be one thing if you're on station pumping oil and making money, but for SpaceX it would be just a massive O&M money sink if the plan is to just catch a rocket every few weeks or even days.

 

[ADSWNJ]

I agree with you, C3PO. Having a platform with fast actuators to adjust the platform is a cool idea.

Not sure that the hover mode will ever happen, given the min thrust characteristics of the engines and the thrust to weight ratio at landing time. Need more out of the box thinking.

 

[Thunder Chicken]

There is some question about the state of the stage. There is some discussion that the stage may be upright on (or in) the deck.

Landing looks "rough":

 

[Andy44]

Everything you say is sensible, but to the extent that Elon Musk is a real life James Bond villain (I mean, come on, even his name sounds like it), I think he really needs a big hyper-expensive sea base to use for space vehicles like something out of the Thunderbirds, and one of those things looks about right.

'Jeff Bezos' does not sound like a Bond villain name...

But 'Richard Branson' could be one.

 

[RisingFury]

I agree with you, C3PO. Having a platform with fast actuators to adjust the platform is a cool idea.

Actuators and the entire mechanism would have to be strong enough not just to take the weight of the rocket, the deck, but the impact itself. Having an actuator system that can compensate for say ~1 m waves and ~30° bank in two axes, while maintaining that kind of strength will be a bit tricky.

Not sure that the hover mode will ever happen, given the min thrust characteristics of the engines and the thrust to weight ratio at landing time. Need more out of the box thinking.

The hover mode won't happen. They've already demonstrated the ability the land the rocket WAY past hover conditions. The problem this time wasn't that there was too much thrust, but that there was too little.