SpaceX launches resumes





After the break, almost half a year of the accident launch vehicle Falcon-9 (in the mission of CRS-7 service ISS), the company SpaceX is resuming flights. Start is planned for the window between 4.00 and 5.00 pm on 20 December to Moscow time (20.00 - 21.00 pm on 19 December, Eastern Standard Time). This launch should be withdrawn 11 satellites telecommunications company Orbcomm. The launch will be carried out with a new version of the launch vehicle - the Falcon 9 v1.2 (according to other sources - the name of the Falcon 9 v1.1 Full Thrust).

Satellites Orbcomm, weighing 172 kilograms each, will be withdrawn HEO:


Work on a new version of the missile were launched before the accident, but SpaceX after it decided to make an inspection of all used in the launch vehicle equipment for compliance with certification that the much delayed training. Falcon-9 v1.2 is to replace an older version of the Falcon 9 v 1.1 on a permanent basis (assuming one more run v 1.1 contract NASA and NOAA). September 21 have already been inspected improved version of the first stage:



In preparation for the upcoming flight, the first step was taken to the start More November 20 to the end of November has been delivered and the second stage. The static test firing of the missile exactly which flight - will be held on December 16, three days before the start. Already preparing for the start of two more missiles (the old and new versions) for starts in January, by February, preparing the next flight to the ISS.

The new version of the rocket thrust would increase by 15%, capacity tanks by 10% (by increasing the density of the fuel, which is achieved by cooling the liquid oxygen to the lower temperatures). Similar improvements are provided in the second stage. In general, the missile "grew up" on the 1, 5 meters, starting weight increased from 506 to 541 tons. This allows not only for the planting program CRS (Dragon-fly and the ISS), which were carried out with a significant "underload", but in the other the flights.

This flight provides a landing of the first stage on the ground (with the return of the rocket to the launch site), unlike previous attempts to land on a barge (the rate of rocket flight), at the moment it is reported that SpaceX has not yet managed to get permission to land, and perhaps to test landing on the land will not succeed. It was also stated that after the launch of the satellites in the second stage will remain a significant part of the fuel, and after the separation of the satellite, it is supposed to conduct additional tests (attempts to return to its orbit is not provided).

About the course of the investigation of the accident CRS-7: July 28, 2015, after the regular take-off, in a tank of liquid oxygen the Falcon 9 there was a sharp increase in pressure of about 139 seconds of flight, which resulted in the accident. This preliminary assessment, further investigation will reveal more.
Before the accident, the first stage of the rocket, including all nine engines Merlin 1D worked normally, the first stage of a full-time job continued for a few seconds after the release of pressure. Dragon ship survived the accident and continued to transmit information until it disappeared over the horizon.

SpaceX being investigated under the supervision of the Federal Aviation Agency, with the participation of NASA and US Air Force. Collection of flight data was not as simple as because of the large amounts of data - 3,000 telemetry channels, video review and inspection of the wreckage, and due to the rapidly evolving process of the accident.

From the first indication to the loss of all telemetry - it has been only 0, 893 seconds. The last few weeks (report published July 25 - approx. Trans.) Team of engineers spent thousands of hours in the process of meticulous data, comparing data rockets at millisecond to understand what the reason was preceded by accident, and the final loss of telemetry at 0, 893 seconds.
At this time, the investigation continues, SpaceX and the team involved in the investigation continues to analyze a significant amount of data, conduct additional tests in order to fully test this version. However, with the current data we can say that the probable cause was identified.

Preliminary analysis showed that increasing the pressure in the oxygen tank top stage was caused by a defective part of the structure (a spacer) in the second stage. Booster the Falcon 9 has several hundred spacers, and over the lifetime of a few thousand was used. Spacer, which we consider faulty, has been certified to the load due to 4500 kilograms (10 000 pounds), but has failed already at five times lower load - 700 kilogram (2 000 pounds).

In the case of CRS-7 mission, presumably one of these items in the second stage collapsed at 138 seconds of flight. The system pressurization worked normally, but after the destruction of the struts geliumnaya system was destroyed. This increase in pressure in the second step led to the fact that the stage has lost structural integrity within a time less than one second.

Despite the fact that these spacers were used in all the previous flights of the Falcon 9, and have been certified for loads far in excess of flight, SpaceX will no longer use these spacers in their products. In addition, SpaceX will conduct additional checks of all equipment used in the launch vehicle compliance certification documentation.

As noted above, these are preliminary findings. Our investigation will continue to check the reliability of all parts of the launch vehicle, at the moment, we expect the return of flying in the fall and execution of all flights scheduled for 2015.

Despite the regrettable loss of CRS-7, analysis of events in the end, will make our launch vehicles safer and more reliable for all customers, including NASA, the US Air Force and commercial customers. It is critical that our carrier rockets will be even safer when we start the transportation of US astronauts on the ISS in 2017.

Original text
The same reason (the loss of the launch vehicle in connection with the destruction of the spacer holding tank with liquid helium) Musk voiced at conference ISSRDC 2015 . Currently SpaceX has more than 60 orders for the общую worth over 7 billion $ .

Joke of humor Find the 10 differences
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Source: geektimes.ru/post/266524/

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