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An opinion piece on a need for focus
In the wake of SpaceX's most recent anomaly:
http://arstechnica.com/science/2016/...acex-to-focus/ rick jones -- Don't anthropomorphize computers. They hate that. - Anonymous these opinions are mine, all mine; HPE might not want them anyway... feel free to post, OR email to rick.jones2 in hpe.com but NOT BOTH... |
#2
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An opinion piece on a need for focus
Le 02/09/2016 ŕ 20:47, Rick Jones a écrit :
In the wake of SpaceX's most recent anomaly: http://arstechnica.com/science/2016/...acex-to-focus/ rick jones “Sending thousands to colonize Mars may just have to be put on the back burner until he can send three people to ISS.” Interesting article. |
#3
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An opinion piece on a need for focus
JF Mezei wrote:
Proper change control could limit manned vehicle to only versions that have flown at least X times without fail. Cargo ones could adopt improvements constantly. (once an improvement has flown enough times, it can be incorporated in the design for manned flight). Perhaps, but SpaceX's history to date hasn't suggested they want to have two versions of the Falcon 9 going at the same time. In fact, their payload user's guide touts how the Falcon 9 is going to be even safer for customer payloads because it has been built around the idea of man-rating the launcher. As for the mention of schedule importance in another thread, the way the launch manifest (when it was still published with such information) kept showing the launch dates of various customers slipping, and the way things continue to seem to slip (even prior to this recent anomaly) suggests that anyone currently a SpaceX customer isn't worrying much about schedules. Yet anyway. rick jones -- The computing industry isn't as much a game of "Follow The Leader" as it is one of "Ring Around the Rosy" or perhaps "Duck Duck Goose." - Rick Jones these opinions are mine, all mine; HPE might not want them anyway... feel free to post, OR email to rick.jones2 in hpe.com but NOT BOTH... |
#4
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An opinion piece on a need for focus
JF Mezei wrote:
Proper change control could limit manned vehicle to only versions that have flown at least X times without fail. Cargo ones could adopt improvements constantly. (once an improvement has flown enough times, it can be incorporated in the design for manned flight). Here we go again. Read the following closely: THEY DO NOT CONSTANTLY TINKER WITH THE ****ING ROCKETS. Which part of that don't you understand? -- "Some people get lost in thought because it's such unfamiliar territory." --G. Behn |
#5
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An opinion piece on a need for focus
On Saturday, September 3, 2016 at 9:57:00 AM UTC+12, JF Mezei wrote:
On 2016-09-02 14:47, Rick Jones wrote: In the wake of SpaceX's most recent anomaly: http://arstechnica.com/science/2016/...acex-to-focus/ The article writer focuses on 2 failures in 15 months. Could have equally said 2 failures in 24 months. Or a 100% failure rate in Sept 2016. The fact that there are some employees looking at feasability of going to Mars doesn't prevent work from being done to improve reliability of Falcon 9. As I recall, the first of those was due to some new strut not up to task in a tank. Proper change control could limit manned vehicle to only versions that have flown at least X times without fail. Cargo ones could adopt improvements constantly. (once an improvement has flown enough times, it can be incorporated in the design for manned flight). SpaceX has not been happy with the FTS system provider. That is one piece that SpaceX has outsourced and that contractor has consistently been late in delivering their product, and have consistently had problems and delays. If the current explosion is related to FTS this is a strong argument that SpaceX should bring that part of its supply chain in-house. Includes info regarding debris, flight termination, risk calculations: https://www.federalregister.gov/arti...ion-for-launch https://www.federalregister.gov/arti...nts-for-launch the predicted risk of RTLS exceeds the limit normally imposed and a waiver of this limit was accepted by the authorities on this occasion. The predicted risk will be adjusted in light of real data, but no one was hurt, so the adjustment for casualties resulting from a launch will be quite low. SpaceX will be keen to make such waivers unnecessary in the future. It is a testament to the process FAA and the Air Force have for their ranges that no accidents involving casualties on the ground have happened in the US. Of course as long as the actual number of casualties is 0 from US ranges, making estimates on the actual risk involves a lot of guesses. The most recent rocket-related incidents with fatalities in the US are the cold flow test stand explosion related to SpaceShip Two engine development, and the Titan 4 SRB test stand incident at Edwards in 1990. Neither had anything to do with an actual launch. Here is the launch manifest for the rest of the year; Cape Canaveral Air Force Station & Kennedy Space Center, Florida JULY 28 – ULA / Atlas-V 421 rocket / NROL-61 Classified / 8:37 a.m. EDT AUGUST 19 – ULA / Delta-IV Medium+ (4,2) rocket / AFSPC-6 for USAF / Launch Window TBD AUGUST TBD – SpaceX / Falcon-9 rocket / JCSAT-16 satellite / Launch Date & Window TBD SEP 8 – ULA / Atlas-V 411 rocket / OSIRIS-REX asteroid sample return mission / 7:05 – 9:05 p.m. EDT * * * DESTROYED * * * SEP TBD – SpaceX / Falcon-9 rocket / AMOS-6 satellite / Launch Date & Window TBD SEP TBD – SpaceX / Falcon-9 rocket / SES-10 satellite / Launch Date & Window TBD SEP TBD – SpaceX / Falcon-9 rocket / EchoStar 23 satellite / Launch Date & Window TBD * * * DESTROYED * * * OCT 3 – ULA / Atlas-V 401 rocket / SBIRS GEO 3 satellite for USAF / Launch Window TBD OCT 20 – ULA / Delta-IV Medium+ (5,4) / Wideband Global SATCOM-8 satellite for USAF / Launch Window TBD * * * RESCHEDULED * * * OCT TBD – SpaceX / Falcon-9 rocket / SES-11 (Echostar 105) satellite / Launch Date & Window TBD * * * RESCHEDULED * * * NOV 4 – ULA / Atlas-V 541 rocket / GOES-R Weather satellite / 5:40 p.m. EDT NOV 11 – SpaceX / Falcon-9 rocket / CRS-10 ISS Resupply for NASA / Launch Window TBD NOV 21 – Orbital ATK / Pegasus air launch / NASA’s CYGNSS satellite / Launch Window TBD NOV TBD – SpaceX / Falcon Heavy Inaugural DEMO Flight / Launch Date & Window TBD DEC 1 – ULA / Atlas-V 401 rocket / NROL-79 / Launch Window TBD DEC 8 – ULA / Atlas-V 431 rocket / EchoStar-19 satellite / Launch Window TBD Vandenberg Air Force Base, California SEP 12 – SpaceX / Falcon-9 rocket / Iridium Next satellites 1-10 / 10:33 p.m. PDT SEP 15 – ULA / Atlas-V 401 / WorldView-4 satellite / 11:30-11:44 a.m. PDT OCT TBD – Orbital ATK / Minotaur-C rocket / Skysat satellites for Google / Launch Date & Window TBD OCT TBD – SpaceX / Enhanced Falcon-9 v1.1 / Formosat 5 & misc cubesats / Launch Date & Window TBD DEC 1 – ULA / Atlas-V 401 / NROL-79 classified / Launch Date & Window TBD DEC TBD – SpaceX / Falcon-9 rocket / Iridium Next satellites 11-20 / Launch Date & Window TBD Wallops Flight Facility, VA AUGUST 22 – Orbital ATK / Antares Return-to-Flight / Cygnus OA-5 ISS Resupply / Launch Window TBD DEC 30 – Orbital ATK / Antares / Cygnus OA-7 ISS Resupply / Launch Window TBD Here is what happened during the DSCOVR launch 15 Jan 2015 The Deep Space Climate Observatory (DSCOVR) Following a well-trodden processing regime, the Falcon 9 v1.1 moved smoothly through a Static Fire Test of its nine Merlin 1D first-stage engines on Saturday, 31 January, after which it was removed from SLC-40 for the installation of its DSCOVR payload. It then headed into the Launch Readiness Review (LRR) and Flight Readiness Review (FRR) milestones and is expected to return to SLC-40 and be raised to the vertical tomorrow (Saturday). As with Dragon cargo missions to the ISS, the DSCOVR launch window is an instantaneous one, with no margin to accommodate last-minute technical issues or poor weather. If the vehicle cannot launch at the prescribed time on Sunday, the attempt will be scrubbed and the countdown clock recycled to support the backup opportunity on Monday. After rollout, the Falcon 9 v1.1 will be fueled with liquid oxygen and a highly refined form of rocket-grade kerosene, known as “RP-1.” The cryogenic nature of the oxygen—whose liquid state exists within a temperature range from -221.54 degrees Celsius (-368.77 degrees Fahrenheit) to -182.96 degrees Celsius (-297.33 degrees Fahrenheit)—requires the fuel lines of the engines to be chilled, in order to avoid thermally shocking or fracturing them. All propellants should be fully loaded within one hour and at 5:57 p.m. Sunday, assuming no technical constraints, the countdown will pass its final “Go/No-Go” polling point of all stations at T-13 minutes. The Terminal Countdown will get underway at T-10 minutes, during which time the Merlin 1D engines will be chilled, ahead of their ignition sequence. All external power utilities from the Ground Support Equipment (GSE) will be disconnected and at 6:05 p.m. the roughly 90-second process of retracting the “strongback” from the vehicle will occur. The Flight Termination System (FTS)—which is tasked with destroying the Falcon 9 v1.1 in the event of a major accident during ascent—will be placed onto internal power and armed. By T-2 minutes and 15 seconds, the first stage propellant tanks will attain flight pressure, after which the engines will be purged with gaseous nitrogen and at T-60 seconds the SLC-40 complex’s “Niagara” deluge system of 53 nozzles will come to life, flooding the pad surface and flame trench with 30,000 gallons (113,500 liters) of water, per minute, to suppress acoustic energy radiating from the engine exhausts. At T-3 seconds, the Merlins will roar to life, ramping up to a combined thrust of 1.3 million pounds (590,000 kg). Following computer-commanded health checks, the stack will be released from SLC-40 to begin SpaceX’s second mission of 2015. Immediately after clearing the tower, the booster will execute a combined pitch, roll, and yaw program maneuver to establish itself onto the proper flight azimuth to deliver DSCOVR into space. Eighty seconds into the climb uphill, the vehicle will exceed the speed of sound and experience a period of maximum aerodynamic duress—colloquially dubbed “Max Q”—on its airframe. At about this time, the Merlin 1D Vacuum engine of the second stage will undergo a chill-down protocol, ahead of its own ignition later in the ascent. At 6:12 p.m., 130 seconds after liftoff, two of the first-stage engines will throttle back, in order to reduce the rate of acceleration at the point of Main Engine Cutoff (MECO). Finally at T+2 minutes and 58 seconds, the seven remaining engines will shut down, and, a few seconds later, the first stage will separate from the rapidly ascending stack. It will then attempt the second ASDS landing in the Atlantic Ocean. Traveling at a velocity of 2,900 mph (4,670 km/h), the stabilization of the 150-foot-tall (46-meter) first stage has been likened to someone balancing a rubber broomstick on their hand, in the midst of a fierce windstorm. Three Merlin firings will be performed to steadily reduce this velocity and stabilize the first stage: an initial “boost-back” burn will adjust the vehicle’s impact point, after which a “supersonic retro-propulsion” burn will slow it to about 560 mph (900 km/h) and a final “landing” burn will bring this down still further to just 4.5 mph (7.2 km/h). During the final burn, the first stage will deploy its four extendable landing legs and a quartet of lattice-like hypersonic grid fins—configured in an “X-wing” layout—will be unfurled to control the lift vector and, together with engine gimbaling, will enable a precise touchdown on the ASDS. “Grid fins perform well in all velocity ranges, including supersonic and subsonic speeds, with the exception of the transonic regime, due to the shockwave enveloping the grid,” Spaceflight101 noted in June 2014. “These properties make them ideally suitable for the Falcon 9 first stage that starts out at supersonic speeds and returns to subsonic velocity as it travels through the atmosphere, en-route to the landing site.” With two degrees of freedom, the fins have the capacity to rotate and tilt, thereby enabling them to eliminate roll rates and maintaining control during flight. Unfortunately, it would appear that the failure of the fins to operate correctly—having run out of sufficient hydraulic fluid during atmospheric flight—was a contributory factor in last month’s failure. That shortfall is expected to be resolved for this second attempt. With the first stage gone, the turn will then come for the Falcon 9 v1.1’s restartable second stage, whose Merlin 1D Vacuum engine—with a maximum thrust of 180,000 pounds (81,600 kg)—will come to life to support two discrete “burns,” then set DSCOVR free about a half-hour after leaving the Cape. The small spacecraft will then be on its own to complete the 110-day journey to reach the L1 Lagrange Point and should be on-station by the end of May. |
#6
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An opinion piece on a need for focus
On Saturday, September 3, 2016 at 12:35:24 PM UTC+12, Fred J. McCall wrote:
JF Mezei wrote: Proper change control could limit manned vehicle to only versions that have flown at least X times without fail. Cargo ones could adopt improvements constantly. (once an improvement has flown enough times, it can be incorporated in the design for manned flight). Here we go again. Read the following closely: THEY DO NOT CONSTANTLY TINKER WITH THE ****ING ROCKETS. Which part of that don't you understand? -- "Some people get lost in thought because it's such unfamiliar territory." --G. Behn You have no idea what you're talking about. What part of that don't you understand? |
#7
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An opinion piece on a need for focus
Jesus, Mook, let it go until we actually know something. There is no
reason to believe there was an FTS problem other than that dingleberry you pulled off your ass telling you that it was. William Mook wrote: SpaceX has not been happy with the FTS system provider. That is one piece that SpaceX has outsourced and that contractor has consistently been late in delivering their product, and have consistently had problems and delays. If the current explosion is related to FTS this is a strong argument that SpaceX should bring that part of its supply chain in-house. snip MookSpew -- "Ordinarily he is insane. But he has lucid moments when he is only stupid." -- Heinrich Heine |
#8
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An opinion piece on a need for focus
William Mook wrote:
On Saturday, September 3, 2016 at 12:35:24 PM UTC+12, Fred J. McCall wrote: JF Mezei wrote: Proper change control could limit manned vehicle to only versions that have flown at least X times without fail. Cargo ones could adopt improvements constantly. (once an improvement has flown enough times, it can be incorporated in the design for manned flight). Here we go again. Read the following closely: THEY DO NOT CONSTANTLY TINKER WITH THE ****ING ROCKETS. Which part of that don't you understand? You have no idea what you're talking about. What part of that don't you understand? Keep not letting reality intrude, Mookie. It's a scary world out there.... -- "Ordinarily he is insane. But he has lucid moments when he is only stupid." -- Heinrich Heine |
#9
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An opinion piece on a need for focus
JF Mezei wrote:
On 2016-09-02 20:07, Rick Jones wrote: Perhaps, but SpaceX's history to date hasn't suggested they want to have two versions of the Falcon 9 going at the same time. Depends on definition of "man rated". If it requires things are properly tested before manned flight, It sort of does, but not what you're thinking of. ... then it makes sense to implement changes/improvements on cargo rockets first and once they have flown enough, you then implement those changes to man rated rockets. No, it doesn't. You don't seem to understand that engineering is not just "let's cobble a bit and see what happens". This is more of a logistics issue than one of keeping 2 models in production. Except you only have the 'logistics problem' because you are keeping 2 models in production. You build your V1.2 rockets for cargo, but keep parts to build a V1.1 for manned flight, but after V1.2 has flown enough, manned flighst use V1.2 as well. So it is a staggered impememntation instead of keeping 2 models. You can't define away the fact that you are talking about keeping two models in production. Also, with re-usability, SpaceX will have to deal with inventory of stage1s of different versions. So it has to deal with those logistics anyways. Well, no, it doesn't. In fact, their payload user's guide touts how the Falcon 9 is going to be even safer for customer payloads because it has been built around the idea of man-rating the launcher. The design may have all the features needed for man rated flight, but if the design is constantly tweaked to improve it, then this introduces uncertainties for launch (as with those tank struts that caused catastrophe last year). Which part of the following statement is it that is confusing to you? THEY DON'T CONSTANTLY TWEAK THE ****ING ROCKETS!!!!!!!!!! You make changes in 'blocks', not rocket by rocket. If you're constantly mucking about with the rocket, how do you ever establish the reliability of the thing? Every ****ing one is different under your scheme. NOBODY does that ****. We don't do it with airplanes, either. information) kept showing the launch dates of various customers slipping, and the way things continue to seem to slip (even prior to this recent anomaly) suggests that anyone currently a SpaceX customer isn't worrying much about schedules. Yet anyway. Customers can't do much but wait. It isn't as if they can go to Wendys if the lineup at McDonalds is too long. Their satellite is designed for launch on a specific rocket (structural attachments etc) and it will take longer to book on new launcher and modify satellite for it. Well, actually they can, if the delay is long enough. If you're liuanching a new GPS satellite, and you already have 30 in orbits that work, a delay isn't a big deal. But if you have already started to sell internet to a remote community and your sattelite is delayed by a year, then you have problems. Different customers have different needs and priorities. Only a huckster like Mook would sell something he doesn't have. -- "Some people get lost in thought because it's such unfamiliar territory." --G. Behn |
#10
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An opinion piece on a need for focus
JF Mezei wrote:
On 2016-09-02 22:08, William Mook wrote: SpaceX has not been happy with the FTS system provider. The shuttle was re-usable and still had range safety. Yes, it did, because it wasn't under positive human control during boost. If it decided to go some weird direction because of a computer glitch there was bugger all anyone could do about it other than stop it. What we're talking about here is similar to a data centre with fancy automated freon/CO2 fire suppression, but fire department still requires highly destructire water sprinklers be installed over all the computer equipment. No, it isn't. Today's rockets don't go "randomly" like a tiny rocket or a balloon that you let fly on its own as it deflates. Except today's rockets can do precisely that. One of the videos Mook posted showed an ArianeSpace launch where the guidance software freaked out and commanded a 90 degree turn. They blew the FTS to stop the rocket. At, or right off the pad, when the rocket explodes, is there a point in range safety since it is already exploding and whether you do range safety or not, it won't make a difference to damage ? (Wallops and now Cap with Falcon9 were at/near pad). You don't understand how Range Safety works. There is ZERO evidence that the FTS on the SpaceX rocket was ever fired and there wouldn't be a reason to do so. And once in the air, they're over the ocean, so what is the point of detonating it ? Chances are that if it malfunctions, it either explodes or ceases to have propulsion and won't make it to any habited areas across the atlantic. We don't roll dice. Let me explain to you how Range Safety works. What they do is they watch the VELOCITY VECTOR of the vehicle. There is a defined 'safety corridor' based on danger to people. When the velocity vector points outside the 'safety corridor' they fire the FTS. You seem to think that the FTS is for 'terminating' rockets that have already blown up. It isn't. The touchy part now is that Falcon9 can return home, and during its return, what if it aims for that cute bikini clad lady on Coco Beach instead of the designated landing pad? I could see the utility of having self destruct in that one case. Works the same way I described above. However, with self destruct, won't debris be spread over greater area and thus cause mroe damage instead of letting rocket fall on the beach? You don't understand what an FTS does. It doesn't just blow up the rocket. It TERMINATES THRUST. Remember, Range Safety is looking at the velocity vector of the vehicle and will blow it BEFORE you have to worry about debris. This **** isn't magic and we've been doing it for a long time. -- "Insisting on perfect safety is for people who don't have the balls to live in the real world." -- Mary Shafer, NASA Dryden |
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