SpaceX Tuesday...
Discussion
hidetheelephants said:
I'm pretty sure the net losses of rockets to RUD has steadily declined since Goddard first involuntarily uttered an expletive when his rocket reduced itself to shrapnel and attempted to kill him.
Well given that was a first and a RUD putting rocket losses at 100% to start you would hope so 
Rocket engineering is hard and unforgiving.
The rocket that blew up the other day was just the 29th Falcon 9 mission and they've made considerable upgrades and changes to the design in just that short 6-year lifespan. It's still really a prototype vehicle. They've lost 2 of them now, so that's a 7% failure rate.
The Ariane 5 rocket used to blow up all the time when it first came out. Not to jinx it, but just last month they completed their 73rd straight launch success. That's over 13 years. Still has a 4.6% failure rate though.
Concorde went from having the best airliner safety record for 27 years, to being one of the worst in just a single crash. The cause of it wasn't even the aircraft's fault, but with only 12 aircraft in service, they suddenly had an 11.36% fatality rate per million miles flown. Generally the rate would be roughly 0.5%. The ubiquitous Boeing 737 (all models) has a 0.27% fatality rate per million miles flown. And boy have those things collectively flown some stellar mileage.
The rocket that blew up the other day was just the 29th Falcon 9 mission and they've made considerable upgrades and changes to the design in just that short 6-year lifespan. It's still really a prototype vehicle. They've lost 2 of them now, so that's a 7% failure rate.
The Ariane 5 rocket used to blow up all the time when it first came out. Not to jinx it, but just last month they completed their 73rd straight launch success. That's over 13 years. Still has a 4.6% failure rate though.
Concorde went from having the best airliner safety record for 27 years, to being one of the worst in just a single crash. The cause of it wasn't even the aircraft's fault, but with only 12 aircraft in service, they suddenly had an 11.36% fatality rate per million miles flown. Generally the rate would be roughly 0.5%. The ubiquitous Boeing 737 (all models) has a 0.27% fatality rate per million miles flown. And boy have those things collectively flown some stellar mileage.
Looks like the most recent Chinese launch didn't go to plan either -
https://spaceflightnow.com/2016/09/02/chinese-offi...
https://spaceflightnow.com/2016/09/02/chinese-offi...
RobDickinson said:
The pace of progress is increasing not decreasing.
I wonder how quickly a sat ejection system could work, it'd be quite an addition to the payload weight for once, and dragonII plans to land on water for emergency situations, something not great for a delicate sat..
I believe the Dragon delivery system now has this escape functionI wonder how quickly a sat ejection system could work, it'd be quite an addition to the payload weight for once, and dragonII plans to land on water for emergency situations, something not great for a delicate sat..
Toaster said:
We live in a world of marketing and corporate spin, 3000 lines of data, well you can probably cut out most of them as it was the upper stage Anomaly sounds nice like collateral damage .
It Blew up lost $200M+ and they are looking for the root cause of the Explosion nice neat words about safety of future manned flights etc, This is another reason why there needs to be a real step change in launch technology or maybe we just have to except every X launches these things will Blow up.
Just a thought here but given the value of the non human cargo shouldn't it have an escape rocket on top like a manned flight? its may have just saved $150M worth of hardware.
can you point us to where SpaceX have ever been anything but transparent when dealing with their launch failures?It Blew up lost $200M+ and they are looking for the root cause of the Explosion nice neat words about safety of future manned flights etc, This is another reason why there needs to be a real step change in launch technology or maybe we just have to except every X launches these things will Blow up.
Just a thought here but given the value of the non human cargo shouldn't it have an escape rocket on top like a manned flight? its may have just saved $150M worth of hardware.
Excellent review of the explosion and its possible consequences by Scott Manley -
https://www.youtube.com/watch?v=Ye0EOENUw0c
https://www.youtube.com/watch?v=Ye0EOENUw0c
A press tour of SLC-40 back in 2012:
https://www.youtube.com/watch?v=_FlhbMraqxA
It's raw, unedited footage really, so just flick through it.
The hanger is only about 500 ft from the launch point, so I imagine the recent blast kinda messed it up a tad.
The Falcon 9 in the hanger is a 1.0 version, with the original engine layout.
The look at the returned Dragon capsule near the end is pretty interesting.
https://www.youtube.com/watch?v=_FlhbMraqxA
It's raw, unedited footage really, so just flick through it.
The hanger is only about 500 ft from the launch point, so I imagine the recent blast kinda messed it up a tad.
The Falcon 9 in the hanger is a 1.0 version, with the original engine layout.
The look at the returned Dragon capsule near the end is pretty interesting.
Eric Mc said:
Excellent review of the explosion and its possible consequences by Scott Manley -
https://www.youtube.com/watch?v=Ye0EOENUw0c
That escape system is phenomenal. What 'g' must it be pulling?!https://www.youtube.com/watch?v=Ye0EOENUw0c
The Orion escape system is similar too - but more advanced than - the Apollo system.
However, there is no law saying that a tractor rocket system is the only way.
The Dragon capsule is also designed to land on land - and therefore has braking rockets to allow a soft landing. The escape rocket system and the landing rocket systems are integrated - so it makes sense to have a "pusher" rocket escape system than a tractor system.
However, there is no law saying that a tractor rocket system is the only way.
The Dragon capsule is also designed to land on land - and therefore has braking rockets to allow a soft landing. The escape rocket system and the landing rocket systems are integrated - so it makes sense to have a "pusher" rocket escape system than a tractor system.
p1stonhead said:
That escape system is phenomenal. What 'g' must it be pulling?!
Pad abort test pulled 6G8x SuperDraco at max = 550,000 N. From ignition to full thrust in 0.1s
If you imagine rope & pulley above the capsule (< 10 tonne) attached to a 55 tonne weight that is then shoved off a cliff...
It can fly away from the booster even at Max Q. I find that difficult to picture, with such aero load on the Dragon doing 2x speed of sound and the booster getting a free draft just inches behind it seems like an impossible task.
Simpo Two said:
Any reason why an 'escape system' couldn't be like the Apollo one? That was designed to haul three men to safety.
Propulsive landing.Mission will need either LES or landing, never both. Might as well use the landing system for LES and save the weight and cost of a separate LES.
A drone view of the Boca Chica facility in South Texas,
https://www.youtube.com/watch?v=oQI3URzHdeM
They're currently still waiting on ground stabilisation work before they can start to really build anything.
https://www.youtube.com/watch?v=oQI3URzHdeM
They're currently still waiting on ground stabilisation work before they can start to really build anything.
Calling it an "anomaly" does come across as rather prissy, but like all industries, the space industry has developed it's own language.
Check out this anomaly of a Delta II rocket back in 1997, when one of the solid rocket boosters let rip.:
https://www.youtube.com/watch?v=z_aHEit-SqA
..and an interesting report from someone who was underneath it:
https://www.youtube.com/watch?v=iJP5ncnLwgE
Check out this anomaly of a Delta II rocket back in 1997, when one of the solid rocket boosters let rip.:
https://www.youtube.com/watch?v=z_aHEit-SqA
..and an interesting report from someone who was underneath it:
https://www.youtube.com/watch?v=iJP5ncnLwgE
SpeedyDave said:
Pad abort test pulled 6G
8x SuperDraco at max = 550,000 N. From ignition to full thrust in 0.1s
If you imagine rope & pulley above the capsule (< 10 tonne) attached to a 55 tonne weight that is then shoved off a cliff...
Would it not descend at 9.81 m/sec2 regardless of weight? Your pulley needs some mechanical advantage I think...!8x SuperDraco at max = 550,000 N. From ignition to full thrust in 0.1s
If you imagine rope & pulley above the capsule (< 10 tonne) attached to a 55 tonne weight that is then shoved off a cliff...
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