{"id":16587,"date":"2015-02-07T21:35:11","date_gmt":"2015-02-07T13:35:11","guid":{"rendered":"https:\/\/wp-productionenv-bjg9h2g2bgg5b8aa.southeastasia-01.azurewebsites.net\/news\/new-challenges-await-spacexs-next-rocket-landing-attempt\/"},"modified":"2015-02-07T21:35:11","modified_gmt":"2015-02-07T13:35:11","slug":"new-challenges-await-spacexs-next-rocket-landing-attempt","status":"publish","type":"post","link":"https:\/\/starpath.global\/news\/new-challenges-await-spacexs-next-rocket-landing-attempt\/","title":{"rendered":"New challenges await SpaceX\u2019s next rocket landing attempt"},"content":{"rendered":"
\"A
A view of SpaceX\u2019s rocket landing ship in the Atlantic Ocean. Credit: SpaceX via Elon Musk<\/figcaption><\/figure>\n

A rocket recovery team positioned off Florida\u2019s East Coast is standing by for liftoff Sunday of a Falcon 9 launcher with a space weather satellite, but the demanding trajectory of the flight adds more unknowns to the company\u2019s dicey endeavor to land the booster on a ship at sea, a SpaceX official said Saturday.<\/p>\n

Aiming to perfect an unprecedented flyback maneuver with the Falcon 9 rocket\u2019s first stage, SpaceX officials say they made changes to the booster after it crash landed on a specially-outfitted barge following a successful Jan. 10 launch to resupply the International Space Station.<\/p>\n

The experiments are leading up to SpaceX\u2019s plans to refurbish and reuse rocket boosters in a bid to slash the cost of launching satellites into orbit.<\/p>\n

Hans Koenigsmann, SpaceX\u2019s vice president of mission assurance, was careful to describe the rocket reusability experiment as a strictly secondary objective to the primary purpose of Sunday\u2019s flight: dispatching NOAA\u2019s $340 million Deep Space Climate Observatory toward a post a million miles from Earth.<\/p>\n

\u201cWe had some adjustments after the last fairly hard landing on CRS-5,\u201d Koenigsmann told reporters Saturday, referring to the fiery touchdown Jan. 10. \u201cWe fixed the problems.\u201d<\/p>\n

The crash destroyed the rocket, but the booster\u2019s guidance system and engines apparently functioned as designed, steering the 14-story stage to the football field-sized barge before it ran out of hydraulic fluid to drive four aerodynamic stabilization fins in the final moments of the Falcon 9\u2019s vertical descent.<\/p>\n

SpaceX chief executive Elon Musk said the new launcher for Sunday\u2019s flight carries \u201cway more\u201d hydraulic fluid to remedy the problem. At least it should explode for a different reason, Musk quipped on Twitter.<\/p>\n

\u201cWe ran out of hydraulic fluid shortly after the landing burn started,\u201d Koenigsmann said. \u201cIt was close. Personally, I feel this last time was an enormous accomplishment on the way to refurbishment and reusability of vehicles. I don\u2019t see this as a failure at all. To me, it\u2019s just a development step.\u201d<\/p>\n

\"Hans
Hans Koenigsmann, SpaceX\u2019s vice president of mission assurance. Credit: NASA\/Kim Shiflett<\/figcaption><\/figure>\n

The unoccupied landing platform \u2014 which survived the Jan. 10 landing attempt relatively unscathed \u2014 is stationed about 370 miles east-northeast of Cape Canaveral for Sunday\u2019s launch, Koenigsmann said.<\/p>\n

The weather in the landing zone should be favorable, according to a forecast issued by Mike McAleenan, the U.S. Air Force\u2019s launch weather officer.<\/p>\n

The outlook calls for mostly clear skies, good visibility, and waves of 2 to 4 feet. Surface winds will be out of the south at about 10 knots, McAleenan said.<\/p>\n

Conditions at the Falcon 9\u2019s launch site at Cape Canaveral are also predicted to be near-ideal Sunday, with a 90 percent chance of acceptable weather.<\/p>\n

The modified barge is dubbed an autonomous spaceport drone ship and christened as \u201cJust Read the Instructions\u201d in a nod to planet-sized starships featured in science fiction author Iain M. Banks\u2019 Culture novels, according to a report in Tor.com.<\/p>\n

The particulars of Sunday\u2019s launch mean SpaceX has to forego one of the three braking burns employed on the Falcon 9\u2019s usual descent profile. Instead of re-firing a subset of the first stage\u2019s nine kerosene-fueled Merlin engines three times, there will be two ignitions on the way back to Earth on Sunday.<\/p>\n

\u201cThere are a couple of differences in the trajectory,\u201d Koenigsmann said. \u201cWe will perform an entry burn and a landing burn. The speed of the stage coming in to entry is actually higher, and that \u2026 makes it a little less likely to succeed.\u201d<\/p>\n

The initial \u201cboost-back\u201d burn designed to drive the rocket back toward Florida has been omitted for Sunday\u2019s mission.<\/p>\n

\u201cWe had an early burn originally,\u201d Koenigsmann said. \u201cThat burn is what we can\u2019t do this time because all the propellant goes to the primary mission.<\/p>\n

Sunday\u2019s launch is set for 6:10:12 p.m. EST (2310:12 GMT) from Cape Canaveral\u2019s Complex 40 launch pad. The timing of the blastoff two minutes after sunset could put on a sky show for spectators for hundreds of miles across Florida.<\/p>\n

\u201cWe will flip the stage around after separation 180 degrees,\u201d Koenigsmann said. \u201cThis is a sunset launch, and it\u2019s probably very good to see. It\u2019s probably very visible in the sky what we do, and you can see the first stage moving around. It will then coast, go through apogee, and will begin to descend, and that\u2019s when the entry burn happens.\u201d<\/p>\n

The booster will reach an altitude of about 130 kilometers, or 80 miles, on an arcing path away from Cape Canaveral at an azimuth of about 70 degrees \u2014 roughly east-northeast.<\/p>\n

\"Engineers
Engineers added four grid fins to the Falcon 9 rocket\u2019s booster stage for added stability. This image shows the fins on the rocket before the Falcon 9\u2019s launch Jan. 10. Credit: SpaceX<\/figcaption><\/figure>\n

After the entry burn, the rocket will drop through the atmosphere, using the friction of the air to slow down from around Mach 5, according to Koenigsmann. Once booster reaches a speed about 250 meters per second (559 mph) and extends its four hydraulically-actuated fins, it will re-ignite its center engine for a final time and deploy four carbon fiber and aluminum honeycomb landing legs to a span of 70 feet.<\/p>\n

It should reach the ship about 9 minutes after liftoff, Koenigsmann said.<\/p>\n

Technicians will be stationed a few miles away from the drone ship, ready to secure the rocket with welded steel shoes and vent leftover propellant and gases from the booster before it travels back to port in Jacksonville, Florida.<\/p>\n

That\u2019s assuming everything goes according to plan.<\/p>\n

Koenigsmann stuck with Musk\u2019s prediction of a 50 percent chance of sticking the landing before the Jan. 10 launch.<\/p>\n

\u201cTo me, we fixed one problem that we had last time,\u201d Koenigsmann said. \u201cThere might be issues ahead of us. Obviously, this is a difficult thing, and at the same time, the trajectory is more difficult (for this launch).\u201d<\/p>\n

He said the booster will encounter twice the aerodynamic pressure experienced during the Jan. 10 flight.<\/p>\n

The next Falcon 9 launch scheduled for Feb. 27 will haul two communications spacecraft into geostationary transfer orbit for Eutelsat and Asia Broadcast Satellite. The high-altitude target orbit for the hefty telecom payloads will require nearly all of the Falcon 9 rocket\u2019s first stage propellant load, and SpaceX plans to leave off the booster\u2019s landing legs and not attempt a touchdown on the drone ship.<\/p>\n

There are more launches later this year where SpaceX could attempt another shipboard landing, before eventually trying a touchdown on land.<\/p>\n

\u201cThere\u2019s continuous improvement,\u201d Koenigsmann said. \u201cWe have plenty of opportunities over the next year to try this out and perfect the landing part.\u201d<\/p>\n

At the same time, Koenigsmann says he would like to see attention on the part of the launch going up rather than the piece coming down.<\/p>\n

\u201cIt\u2019s very important not to get distracted from the primary mission.\u201d<\/p>\n

Follow Stephen Clark on Twitter: @StephenClark1.<\/i><\/b><\/p>\n","protected":false},"excerpt":{"rendered":"

A view of SpaceX\u2019s rocket landing ship in the Atlantic Ocean. Credit: SpaceX via Elon Musk A rocket recovery team positioned off Florida\u2019s East Coast is standing by for liftoff Sunday of a Falcon 9 launcher with a space weather satellite, but the demanding trajectory of the flight adds more unknowns to the company\u2019s dicey […]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"","ping_status":"","sticky":false,"template":"","format":"standard","meta":{"_acf_changed":false,"inline_featured_image":false,"footnotes":"","_links_to":"","_links_to_target":""},"categories":[2],"tags":[3799,2308,479,311,316],"class_list":["post-16587","post","type-post","status-publish","format-standard","hentry","category-news","tag-autonomous-spaceport-drone-ship","tag-dscovr","tag-falcon-9","tag-reusability","tag-spacex"],"acf":[],"_links":{"self":[{"href":"https:\/\/starpath.global\/blog\/wp-json\/wp\/v2\/posts\/16587"}],"collection":[{"href":"https:\/\/starpath.global\/blog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/starpath.global\/blog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/starpath.global\/blog\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/starpath.global\/blog\/wp-json\/wp\/v2\/comments?post=16587"}],"version-history":[{"count":0,"href":"https:\/\/starpath.global\/blog\/wp-json\/wp\/v2\/posts\/16587\/revisions"}],"wp:attachment":[{"href":"https:\/\/starpath.global\/blog\/wp-json\/wp\/v2\/media?parent=16587"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/starpath.global\/blog\/wp-json\/wp\/v2\/categories?post=16587"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/starpath.global\/blog\/wp-json\/wp\/v2\/tags?post=16587"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}