|
|
|
Thread Tools | Display Modes |
#1
|
|||
|
|||
Telemetry data from SpaceX Youtube
87 620
positioning retro burns to slow. It looks like. One thing I might need to clarify is my conclusion. When I say "shut Falcon9 down" I am referring to a man-rating for the craft. Perfection is required. Upgrading Falcon9 to perfect is going to cost more than designing and testing a rocket intended as man-rated from first concept. It is a real hard challenge, from accurate and durable guidance system to perfect return capsule de-orbit engine ejection. Pushing used engines is ok for satellites. As an aside. Robert Shawyer's "impossible drive" is well matched to the job of correcting the satellites sent into elliptical orbit. It is fuel-less and runs on a solarpanel. Get orbit data of the quality of NORAD or NASA. It appears well suited to station keeping for 22,000 mile high communications satellites also-because it was designed so. I was happy to be the only proponent for Shawyer in the New Scientist internet discussion bulletin board. In general it is easier to go the Shawyer and fair deal directly for building rights. It is ridiculously easy as such a thruster. |
#2
|
|||
|
|||
Telemetry data from SpaceX Youtube
On Wednesday, January 20, 2016 at 11:15:49 AM UTC-5, wrote:
87 620 positioning retro burns to slow. It looks like. One thing I might need to clarify is my conclusion. When I say "shut Falcon9 down" I am referring to a man-rating for the craft. Perfection is required. Upgrading Falcon9 to perfect is going to cost more than designing and testing a rocket intended as man-rated from first concept. It is a real hard challenge, from accurate and durable guidance system to perfect return capsule de-orbit engine ejection. Pushing used engines is ok for satellites. As an aside. Robert Shawyer's "impossible drive" is well matched to the job of correcting the satellites sent into elliptical orbit. It is fuel-less and runs on a solarpanel. Get orbit data of the quality of NORAD or NASA.. It appears well suited to station keeping for 22,000 mile high communications satellites also-because it was designed so. I was happy to be the only proponent for Shawyer in the New Scientist internet discussion bulletin board. In general it is easier to go the Shawyer and fair deal directly for building rights. It is ridiculously easy as such a thruster. as long as malfunctions dont kill crew, things like excellent escape systems. theres no need to design and build a brand new vehicle. besides with a higher flight rate a cargo craft is more likely to identify saftety issues |
#3
|
|||
|
|||
Telemetry data from SpaceX Youtube
"Fred J. McCall" wrote in message
... bob haller wrote: as long as malfunctions dont kill crew, things like excellent escape systems. There is always some chance of killing crew, but Dragon V2 on Falcon, even with used engines, is probably 'safer' than anything on one of the man-rated boosters that includes solids. Solids and liquids display approximately the same failure rates and there is no reason to believe a 'used' engine that is designed for reuse would be any more failure prone. However, failure modes for solids tend to be sudden and violent, while liquids malfunction in more benign ways. theres no need to design and build a brand new vehicle. besides with a higher flight rate a cargo craft is more likely to identify saftety issues Higher flight rates are indeed more likely to uncover uncommon failure modes so that they can be addressed. [See, Bob? When you make sense I will actually agree with you.] I'm going to have to mark this day. Seriously though, Bob and Fred are right. You can't have perfection (hell airliners aren't perfect, but at this point we've pretty much ironed out most mechanical kinks). And yeah, I'd ride Falcon 9 today. As I've said, if NASA absolutely needed to fly someone today, give me a good lawn chair, a scuba tank and I'd climb into a Dragon cargo module for the ride. (Ok, yeah, I'd really prefer some sort of escape system, but the point is, I think they've got a good track record). -- Greg D. Moore http://greenmountainsoftware.wordpress.com/ CEO QuiCR: Quick, Crowdsourced Responses. http://www.quicr.net |
#4
|
|||
|
|||
Telemetry data from SpaceX Youtube
On Thursday, January 21, 2016 at 10:01:14 AM UTC-5, Greg (Strider) Moore wrote:
"Fred J. McCall" wrote in message ... bob haller wrote: as long as malfunctions dont kill crew, things like excellent escape systems. There is always some chance of killing crew, but Dragon V2 on Falcon, even with used engines, is probably 'safer' than anything on one of the man-rated boosters that includes solids. Solids and liquids display approximately the same failure rates and there is no reason to believe a 'used' engine that is designed for reuse would be any more failure prone. However, failure modes for solids tend to be sudden and violent, while liquids malfunction in more benign ways. theres no need to design and build a brand new vehicle. besides with a higher flight rate a cargo craft is more likely to identify saftety issues Higher flight rates are indeed more likely to uncover uncommon failure modes so that they can be addressed. [See, Bob? When you make sense I will actually agree with you.] I'm going to have to mark this day. Seriously though, Bob and Fred are right. You can't have perfection (hell airliners aren't perfect, but at this point we've pretty much ironed out most mechanical kinks). And yeah, I'd ride Falcon 9 today. As I've said, if NASA absolutely needed to fly someone today, give me a good lawn chair, a scuba tank and I'd climb into a Dragon cargo module for the ride. (Ok, yeah, I'd really prefer some sort of escape system, but the point is, I think they've got a good track record). -- Greg D. Moore http://greenmountainsoftware.wordpress.com/ CEO QuiCR: Quick, Crowdsourced Responses. http://www.quicr.net when is the planned first flight of the manned version.?? |
#5
|
|||
|
|||
Telemetry data from SpaceX Youtube
On 1/21/2016 1:12 AM, JF Mezei wrote:
On 2016-01-20 18:08, Fred J. McCall wrote: failure prone. However, failure modes for solids tend to be sudden and violent, while liquids malfunction in more benign ways. When you look at the antares failure, it was sudden and violent. Actually I disagree. If you go back and review the video https://www.youtube.com/watch?v=BSr4hUcROwo you can see an explosion on one engine but that was not enough to destroy the rocket, what it did however was cause the vehicle to lose significant thrust, enough that it came back to ground but only after a few seconds, which is an eternity in terms of rocket explosions. Plenty of time for an automated launch escape system to activate had there been one. The big explosion and the one that destroyed the rocket occurred after it crashed back into the launch pad. Had that crash occurred just a mere 100-200 ft further to the north, it would have involved the tank farm that fed the pad and the explosion would have been far more spectacular! Orbital/Wallops got very, very lucky there. You can tell this another way as well and that is the absence of radial debris streaming away from the rocket until after the crash back on the pad. A solid engine failure normally generates LOTS of radial debris. Speaking of Wallops, there's a good article in NasaSpaceFlight.com today about the restorations of the pad and the move to the new Antares with the Russian RD-181 engine. As opposed to the old Russian NK-33 derived Aerojet AJ-26, the new engine does not require super-cold LOX, but rather than remove the sub-chiller from the pad, they decided to keep it and use it to mix into the LOX stream along with a sub-chiller bypass in order to maintain better LOX temperature control. This was viewed as a cheaper more viable option than replacing the existing LOX piping with vacuum insulated piping. But then again had the tank farm been totally destroyed would that decision have been the same? Interesting... http://www.nasaspaceflight.com/2016/...s-second-life/ Dave |
#6
|
|||
|
|||
Telemetry data from SpaceX Youtube
On 1/21/2016 10:01 AM, Greg (Strider) Moore wrote:
I'm going to have to mark this day. Seriously me too! Anyone got the phone number for Hell? I'm thinking about calling ahead and booking a ski vacation. ;-) Dave |
#8
|
|||
|
|||
Telemetry data from SpaceX Youtube
"Jeff Findley" wrote in message
... In article , says... wrote: Pushing used engines is ok for satellites. Shuttle was man-rated and flew nothing but used engines. True. I believe that every single SSME was fired on a test stand before it flew for the first time on an orbiter. This is how you screen for "infant mortality" problems. Yeah, I'm pretty sure they were fired on the test stands. In addition, each shuttle did a flight readiness test firing also. (some multiple times do to Return to Flight firings.) Jeff -- Greg D. Moore http://greenmountainsoftware.wordpress.com/ CEO QuiCR: Quick, Crowdsourced Responses. http://www.quicr.net |
|
Thread Tools | |
Display Modes | |
|
|
Similar Threads | ||||
Thread | Thread Starter | Forum | Replies | Last Post |
Telemetry data from SpaceX Youtube | [email protected] | Policy | 16 | January 24th 16 04:16 PM |
SpaceX and NASA Host Teleconference Today on SpaceX 2 Mission to Space Station | Jeff Findley[_2_] | Policy | 5 | March 4th 13 09:40 PM |
T2K orbital telemetry data/ mission results | R Neutron | History | 2 | November 15th 03 06:50 AM |
Telemetry and Command References? | Martin Sagara | Technology | 1 | August 23rd 03 04:48 AM |
51-L RCS Telemetry (Two Details) | John Maxson | Space Shuttle | 3 | August 14th 03 01:56 AM |