SpaceX Falcon 9 v1.1 - Dragon - CRS-5/SpX-5 -Jan. 10, 2015 - DISCUSSION

[NovaSilisko]

Ha! X marks the spot.

Leave it to SpaceX/Elon to want to make a barge presentable before showing it off. ;p

[yg1968]

SpaceX Landing barge.

I prefer Elon's name for it:

Autonomous spaceport drone ship. Thrusters repurposed from deep sea oil rigs hold position within 3m even in a storm.

https://twitter.com/elonmusk/status/536262624653365248

[Jcc]

@elonmusk

Grid fins are stowed on ascent and then deploy on reentry for "x-wing" style control. Each fin moves independently for pitch/yaw/roll.

I wonder if he needs permission from George Lucas (or Disney) to use the term X-Wing. More awesomeness in any case.

[Ben the Space Brit]

SpaceX Landing Barge! It was said that the first stage will land on the barge and then fly back to the landing site. Not sure if it's this mission but an interesting idea.

Do we have any idea of the ASDS's scale? Do the F-9's legs fit inside the yellow circle or the white one?

[rpapo]

SpaceX Landing Barge! It was said that the first stage will land on the barge and then fly back to the landing site. Not sure if it's this mission but an interesting idea.

Do we have any idea of the ASDS's scale? Do the F-9's legs fit inside the yellow circle or the white one?

We've already been told the deck dimensions: 300' by 170'.  From the picture, the ship itself is somewhat longer.  And now we know that the deck will not be flush with the water, nor even close to it.

[mr. mark]

"Base is 300 ft by 100 ft, with wings that extend width to 170 ft.

[Mongo62]

The "wingspan" of the extended landing legs is around 60 feet, so it should fit within the yellow circle (~80 feet in diameter), provided that it lands precisely where it's supposed to.

[Robotbeat]

The barge looks big enough to land a BFR stage.

[StealerofSuns]

How do they plan to secure the stage once it lands?

[NotOnImpact]

New job posting as SpaceX:

Autonomous spaceport drone ship 'X' re-painter.

[yg1968]

@ Using legs as air brakes to drop terminal velocity in half requires slight redesign & more data. Maybe flight 21.

https://twitter.com/elonmusk/status/536268250620125185

[Mark McCombs]

We saw how effective the grid fins worked at low altitude and velocity with F9R Dev1 and now we know they are intended to be used during hypersonic reentry.  I am still wondering if (1) the issue of transonic "choking" has been address with this fin design and (2) if not, will the fins be stowed during this transonic period and then redeployed for landing or (3) will the issue of "choking" simply not influence the vehicle's attitude and control enough to worry about?

[friendly3]

https://twitter.com/elonmusk/status/536262624653365248

Base is 300 ft by 100 ft, with wings that extend width to 170 ft. Will allow refuel & rocket flyback in future.

Amazing! Where will he stop?

[matthewkantar]

Outer circle approx 140' inner is 80'

[docmordrid]

https://twitter.com/elonmusk/status/536262624653365248

Base is 300 ft by 100 ft, with wings that extend width to 170 ft. Will allow refuel & rocket flyback in future.

Amazing! Where will he stop?

Mars? His focus is pretty obvious and whatever it takes is just enough.

[yg1968]

@elonmusk Good luck. We had supersonic control inversion issues with actuated fins, went back to little thrusters that worked at all speeds.

@ID_AA_Carmack No choice. Entry velocity too high for a precision landing with N2 thrusters alone. Must have aero surfaces for pitch trim.

@elonmusk I don't disagree, but I'm concerned. Maybe offset CG or static trim tab for a touch of body lift, then roll it?

https://twitter.com/ID_AA_Carmack/status/536277962803650562

[yg1968]

The flight grid fins look like the ones on this test we did, but larger:

https://twitter.com/elonmusk/status/536326873916375040

[Senex]

https://twitter.com/elonmusk/status/536262624653365248

Base is 300 ft by 100 ft, with wings that extend width to 170 ft. Will allow refuel & rocket flyback in future.

Amazing! Where will he stop?

Three thoughts:
1) Does this end the discussion of whether the Falcon first stage will be shipped back vertically or horizontally.  Neither — it's going to fly back.

2) If the barge cost less to build than one Falcon first stage it pays for itself when it recovers its first launch.

3) I had wondered if Spacex would try to successfully recover a first stage before flying the in-flight abort test.  Why waste a perfectly good rocket. (I realize the aerodynamic forces on the top of the second stage at MaxQ might make recovery impossible.)

[Kabloona]

Does this end the discussion of whether the Falcon first stage will be shipped back vertically or horizontally.  Neither — it's going to fly back.

Not this time, and not for the several other successful barge landings that will be required before FAA/Range
Safety will approve boostback/flyback to the Cape.

[meekGee]

https://twitter.com/elonmusk/status/536262624653365248

Base is 300 ft by 100 ft, with wings that extend width to 170 ft. Will allow refuel & rocket flyback in future.

Amazing! Where will he stop?

Mars.  We already know that.