3 ms·

Was there anything special about the center core other than boosting longer and needing to land out at sea? Seems like they've landed plenty out at sea, but not

by webXL 9y ago

Was there anything special about the center core other than boosting longer and needing to land out at sea? Seems like they've landed plenty out at sea, but not while landing two on land. I thought this was impressive: "With a total of 27 first-stage engines, Falcon Heavy has engine-out capability that no other launch vehicle can match—under most payload scenarios, it can sustain more than one unplanned engine shutdown at any point in flight and still successfully complete its mission." http://www.spacex.com/falcon-heavy http://www.spacex.com/falcon-heavy

phpnode 9y ago
The centre core is significantly strengthened to cope with the additional load from the side boosters. It also has slightly different aerodynamic properties because of the fixed struts that hold the boosters in place. Either of these could have affected the landing. They'll collect data and fix it.
- jpgvm 9y ago
  It ran out of fuel. There was enough to relight the centre engine but not the 3 outer engines required to complete the landing.
  - GraemeL 9y ago
    It didn't actually run out of fuel. It didn't have enough of the hypergolic mix used to ignite the engines (triethylaluminium & triethylborane that causes the green flash sometimes seen at ignition) and only one of the three engines needed for the landing burn re-lit.
eunoia 9y ago
Here are some really rough numbers derived from pausing the live stream. Falcon Heavy Side Booster Separation - 61km, 6,881 km/hr Falcon Heavy Core 1st Stage Separation - 92.5km, 9,474 km/hr Also a link to screen caps of speeds/altitudes of previous Falcon 9 separations http://www.planetary.org/multimedia/space-images/charts/falcon-9-first-stage.html http://www.planetary.org/multimedia/space-images/charts/falc...
NamTaf 9y ago
It is probably the fastest/highest burn they've ever tried to land, and thus needs the most fuel to land, expeirences the most structural stress, etc. etc.

by webXL 9y ago

phpnode 9y ago

The centre core is significantly strengthened to cope with the additional load from the side boosters. It also has slightly different aerodynamic properties because of the fixed struts that hold the boosters in place. Either of these could have affected the landing. They'll collect data and fix it.

jpgvm 9y ago
It ran out of fuel. There was enough to relight the centre engine but not the 3 outer engines required to complete the landing.
- GraemeL 9y ago
  It didn't actually run out of fuel. It didn't have enough of the hypergolic mix used to ignite the engines (triethylaluminium & triethylborane that causes the green flash sometimes seen at ignition) and only one of the three engines needed for the landing burn re-lit.

eunoia 9y ago

Here are some really rough numbers derived from pausing the live stream. Falcon Heavy Side Booster Separation - 61km, 6,881 km/hr Falcon Heavy Core 1st Stage Separation - 92.5km, 9,474 km/hr Also a link to screen caps of speeds/altitudes of previous Falcon 9 separations http://www.planetary.org/multimedia/space-images/charts/falcon-9-first-stage.html http://www.planetary.org/multimedia/space-images/charts/falc...

NamTaf 9y ago

It is probably the fastest/highest burn they've ever tried to land, and thus needs the most fuel to land, expeirences the most structural stress, etc. etc.