SpaceX JUST landed its 1st stage Falcon 9 on a drone ship.

[quade 3]

Incredible achievement.

Wow.

There isn't a replay on YouTube yet, but there will be and it will be spectacular.

https://twitter.com/SpaceX/status/718547446066913280

https://twitter.com/FailedProtostar/status/718542398759038981

quade -
The World's Most Boring Skydiver

[JerryBaumchen 1,081]

Hi Paul,

Quote

SpaceX

One of the student engineers on the Student Rocket Project that I am assisting with is going to work for them next month.

Jerry Baumchen

[gowlerk 1,956]

There is a vid in that twitter feed now. And yes, it's spectacular.

Always remember the brave children who died defending your right to bear arms. Freedom is not free.

[ryoder 1,412]

Video with cute narrator: http://www.theverge.com/2016/4/8/11392138/spacex-landing-success-falcon-9-rocket-barge-at-sea

"There are only three things of value: younger women, faster airplanes, and bigger crocodiles" - Arthur Jones.

[turtlespeed 212]

ryoder

Video with cute narrator: http://www.theverge.com/2016/4/8/11392138/spacex-landing-success-falcon-9-rocket-barge-at-sea

How sexist.

I'm not usually into the whole 3-way thing, but you got me a little excited with that. - Skymama
BTR #1 / OTB^5 Official #2 / Hellfish #408 / VSCR #108/Tortuga/Orfun

[pchapman 262]

Any idea what kind of speed & altitude & distance were involved for that first stage return?

They sure have their control systems worked out, that landing was so nice and smooth, a continual curving approach right to the point of landing. No waiting to get vertical before bringing it all the way in, or hesitation to recalculate before setting down the last few feet.

[ryoder 1,412]

turtlespeed

***Video with cute narrator: http://www.theverge.com/2016/4/8/11392138/spacex-landing-success-falcon-9-rocket-barge-at-sea

How sexist.

...says the guy dreaming about her toes.

"There are only three things of value: younger women, faster airplanes, and bigger crocodiles" - Arthur Jones.

[Phil1111 943]

Meanwhile in Europe:
"Ariane 6.1 and Ariane 6.2

In June 2014 Airbus and Safran surprised the ESA by announcing a counter proposal for the Ariane 6. They also announced a 50/50 joint venture to develop the rocket. This joint venture would also involve buying out the French government's (CNES's) interest in Arianespace.[15][16]

This proposed launch system would come in two variants, the Ariane 6.1 and the Ariane 6.2.[17] While both would use a cryogenic main stage powered by a Vulcain 2 engine and two P145 solid boosters, the Ariane 6.1 would feature a cryogenic upper stage powered by the Vinci engine and boost up to 8,500 kg (18,700 lb) to GTO, while the Ariane 6.2 would use a lower-cost hypergolic upper stage powered by the Aestus engine. The Ariane 6.1 would have the ability to launch two electrically powered satellites at once, while the Ariane 6.2 was intended mostly for government payloads.

French newspaper La Tribune questioned if Airbus Space Systems could match promised costs for their Ariane 6 proposal, and whether Airbus and Safran Group could be trusted when they were found to be responsible for a failure of Ariane 5 flight 517 in 2002 and a more recent 2013 failure of the M51 ballistic missile.[5] The companies were also criticized for being unwilling to take the risks of development and asking for higher initial funding than originally planned to start development - €2.6 billion instead of €2.3 billion. Proposed launch prices of €85 million for Ariane 6.1 and €69 million for Ariane 6.2 were also deemed too high by the La Tribune in comparison to SpaceX[18] During the meeting of EU ministers in Geneva on 7 June 2014 these prices were deemed too high and no agreement with manufacturers was reached.[19]"
https://en.wikipedia.org/wiki/Ariane_6

"PARIS—The head of the European Space Agency’s launcher directorate on July 7(2015) issued a surprising endorsement of the SpaceX Falcon 9 rocket during a French parliamentary hearing that was ostensibly about the status of Europe’s next-generation Ariane 6 vehicle.

Gaele Winters, who is expected to ask ESA’s check-writing body on July 16 to approve a nearly $3 billion contract with Airbus Safran Launchers to develop Ariane 6, said the June 28 Falcon 9 failure in no way changes ESA’s assessment of SpaceX.

“We have seen the outstanding success of Falcon 9,” Winters said. “Despite the issue of about a week ago, it is a fantastic track record for this launcher.”

Winters was addressing the French Parliamentary Office for the Evaluation of Scientific and Technological Choices, which regularly reviews Europe’s and France’s space policy.
- See more at: http://spacenews.com/spacex-looms-large-as-esa-readies-ariane-6-contract/#sthash.tJuiX3sX.dpuf

Three billion Euro for a rocket that cant match Space X costs today. Let alone if Space X establishes reusable first stages and reduce launch costs another 30%. They should rename Ariane, Europork.

[JohnMitchell 14]

pchapman

Any idea what kind of speed & altitude & distance were involved for that first stage return?

They sure have their control systems worked out, that landing was so nice and smooth, a continual curving approach right to the point of landing.

I was wondering that too. Are parachutes used at all? What kind of reentry speeds and aero heating are encountered? Nice google subject for later today.

You're right about the approach. And it's so cool to see the vertical, flaming touchdowns, like something out of old 50's science fiction. My hat is off to those magnificent engineers making it happen.

[billvon 2,475]

>Are parachutes used at all?

Nope. Just drag and a little thrust.

>What kind of reentry speeds and aero heating are encountered?

They separate at about 4000 mph and perform a boostback maneuver with three of the nine engines to reduce the speed further. I think actual re-entry speed is around Mach 4 (3000 mph.) There is some heating (see scorched paint on the bottom of the Falcon when it lands) but most of the abuse is taken by the engines, which are designed to withstand a lot of heat.

Useless trivia - the problem in pulling off the landing was not in getting enough thrust to decelerate, it was having too much. They land with one engine (which means no engine roll control) and it's throttled back almost as far as it can be.

[JohnMitchell 14]

I hadn't really thought about the fact that the booster, being at its lightest, needs relatively little of the available thrust for the soft touchdown. I bet they only made that one engine throttleable. Save the weight, expense and complication on the other ones.

Cool exercise in engineering. Sure, you have the weight penalty of the extra fuel, but balance that against the weight of adding a parachute recovery system and all its structural reinforcements. Plus the economy of reusing your booster. First glance or intuitive solutions are not always the best, or even correct. Engineers make things happen.

[colin2000 0]

All engines are made the same. Only difference is the center engine can gimbal on two axis while the outer 8 engines gimbal in one directions. Since the engines can only throttle down to 70% they have to land in whats called a "hover slam" maneuver. Since there is too much thrust to hover and you use a lot of fuel the longer you are fighting gravity, this is the most efficient way to land the vehicle. Basically the rocket reaches the ground at a velocity of 0 m/s and shuts off the engine before it starts to ascend again. This is a lot harder to do than what Blue Origins is doing with their New Shepard vehicle. They will understand this pretty quick when they start flying their orbital vehicle. They wont be able to land a first stage by sitting there and hovering like New Shepard does now, so they will have to learn this maneuver in the future. What both companies are doing is ground breaking, but what they are doing are not equal as far as difficulty. Some perspective: SpaceX is the only private company/non nation state to ever place a vehicle in orbit and then recover it. On a side note the amount of fuel used for the 3 burn landing of CRS-8 was around 33,000kg (~73,000lbs). The more fuel you need to land, the less payload you can get to orbit. Efficiency is very key to successful orbital recovery/reuse.