Video & Multimedia
Related: About this forumDuckhunter935
(16,974 posts)Lock issue on one of the legs. If not for that it would have been another successful landing like the last one. Even more difficult as it was on the barge this time. Each one brings in more data. How many NASA rockets had issues when they startled. By the way, the satellite was successfully put into orbit.
Great job SpaceX
Cassiopeia
(2,603 posts)They almost got it. I'm sure they will be able to develop this into a reliable system very soon saving us a lot of money.
It was an encouraging attempt. Landed exactly on target as well.
Duckhunter935
(16,974 posts)Shot to the barge. Next time
backscatter712
(26,355 posts)They're thinking it's due to icing from landing in the mists like that.
Sooooooooooo close!
Duckhunter935
(16,974 posts)Spitfire of ATJ
(32,723 posts)Duckhunter935
(16,974 posts)Faulty latch mechanism it appears
Spitfire of ATJ
(32,723 posts)Duckhunter935
(16,974 posts)the legs seem to be able to hold up and have not failed. It was a latch mechanism and not the leg being undersized for the application.
Spitfire of ATJ
(32,723 posts)Duckhunter935
(16,974 posts)it tipped after shutdown.
Spitfire of ATJ
(32,723 posts)backscatter712
(26,355 posts)Every ounce counts on rockets. It costs a fortune to put satellites into orbit.
The legs are designed to be juuuuuuust strong enough to hold up the rocket on landing, when it's only got a little bit of fuel and liquid oxygen left in the tanks.
Spitfire of ATJ
(32,723 posts)Duckhunter935
(16,974 posts)know it was not latched.
Spitfire of ATJ
(32,723 posts)Don't they have an alternate chute recovery?
Duckhunter935
(16,974 posts)I do not think they had chutes as they are conserving weight to get the payloads bigger.
not to mention, I did not say they knew for sure or had sensors. I said it is entirely possible.
Spitfire of ATJ
(32,723 posts)backscatter712
(26,355 posts)The Falcon 9 first stage lands using a "hoverslam" - its engine's minimum power is so powerful it would cause the rocket to shoot back up into the air, on its lowest throttle setting (understand that the rocket stage is pretty light at this point, as its tanks are almost empty). So it has a landing scheme where it fires up the engine juuuuust at the last possible second, so as it's falling, the rocket slows its fall, until exactly at zero altitude, the rocket is slowed to zero descent rate.
There is no abort. You can't boost back into the air and throttle back down - the throttle's as low as it'll go. Apparently, there are a lot of technical reasons why it's hard to make a rocket engine that will "deep-throttle" - they usually will run great at full thrust, and if engineered right, will still run OK at 65% thrust, but they start sputtering and vibrating and shimmying and banging when you try to cut the throttle further than that. Something about instabilities in fuel and LOX flow when they're not flowing at a high enough flow rate - they don't mix well in the combustion chamber as they burn.
Besides, even if the Falcon 9 first stage did have the capability to deep-throttle, and thus abort, go back up, hover, and retry the landing, it wouldn't be able to hover for very long - as it's landing, the rocket's almost out of gas and LOX.
Spitfire of ATJ
(32,723 posts)backscatter712
(26,355 posts)The rocket has to land pretty gently, and on its legs, to be able to survive. The video shows what happens if it tips over - the tanks are not strong enough to handle those kinds of side-forces, they split open, and kablooie.
The landing has to be pretty precise, and parachutes don't do precise.
Spitfire of ATJ
(32,723 posts)PersonNumber503602
(1,134 posts)and use it to attack Space X. Often times they have no idea what exactly Space X is ultimately perfecting with these. It's just Space X either, but with pretty much with anything related to space flight.
yuiyoshida
(41,762 posts)no one was in that...ouch!
Duckhunter935
(16,974 posts)catbyte
(34,170 posts)backscatter712
(26,355 posts)The landing was the only part that didn't go right, and that part's experimental.
Duckhunter935
(16,974 posts)and they learned more from the data.
Cassiopeia
(2,603 posts)I think SpaceX is going to work out the bugs on landing the first stage pretty soon. It will drastically cut down on the cost to launch things into space.
Trajan
(19,089 posts)Plucketeer
(12,882 posts)This thing should already be old hat. For this and the Space-X ship - why not have 4 or 6 long pneumatically extendable stabilizers that would clamp the rocket upright at the moment just before the engine(s) is shut off? I can't believe such a thing isn't already in use!
backscatter712
(26,355 posts)They're extended pneumatically.
The hard part is that the landing legs have to be able to keep a long, skinny object stable, which is why they extend outwards, and they have to be LIGHT, LIGHT, LIGHT. Every ounce counts in launch vehicles, so the suggestions "add another gadget to the vehicle to let it do this!" run into that roadblock.
And the rocket isn't going to land precisely down to the inch - it may be off the center of the landing pad by a few feet in any direction, so that makes developing a gadget on the landing barge to hold the rocket down difficult. That, and the gadget has to be able to withstand the hot exhaust blast from the rocket engine.
Plucketeer
(12,882 posts)Heck, I can go to Lowes right now and buy a laser measuring device. How hard would it be to tie such an input into the control of pneumatic cylinders to where the individual cylinders that surround the landing spot would only move as far as is necessary to follow the rocket to it's touchdown point and extend accordingly?
Duckhunter935
(16,974 posts)backscatter712
(26,355 posts)It did its job as an experimental craft, and did have a few successful landings before that accident.
The Delta Clipper did pave the way for the Falcon 9.
Duckhunter935
(16,974 posts)Plucketeer
(12,882 posts)Even Ben Carson could tell you that.
Delver Rootnose
(250 posts)...it looks to me as if the main cylinder is bent at landing and causes the fall.
Cassiopeia
(2,603 posts)and the direction of the fall that causes that illusion.