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Indian Launchers / Re: ISRO General News
« Last post by worldtimedate on Today at 06:54 AM »
In an unprecedented goodwill gesture, ISRO - probably prodded by Prime Minister Modi - is going to launch small satellite building program for students from 45 developing nations at its own expenses.

Now it will be a matter of curiosity to observe how some of India's smaller but hostile neighbours - that accept as anathema anything gifted by India with one country having even recently returned helicopters gifted by India and some of these countries being hesitant to gleefully accept the service of the SAARC satellite built and launched by India last year and one country even having gone one step further by offering India the financial and even technical resources for the development of the SARC satellite - respond to such magnanimous offer extended by India in the field of Space Program which cannot be expected from any space power.

Source : ISRO to launch free satellite training programme for students from developing nations

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The Indian Space Research Organisation (ISRO) is set to offer students from developing countries an eight-week training programme that will equip them to build small satellites.

Students are expected from 45 countries, with ISRO footing their expenses. They will be trained at the space agency's U.R. Rao Space Centre (URSC) in Bengaluru.

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ISRO chairman Kailasavadivoo Sivan announced the launch of the programme - INDOUNSSP: Capacity Building Programme on Small Satellite Development - at the ongoing UNISPACE Symposium being held in Vienna between 18 June and 21 June. "India is proud to announce an excellent capacity building programme," Sivan said at the symposium. "It is mainly to give opportunity for students from other countries to come to India and get involved in learning of space technology as well as getting hands-on experience in building satellites."

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Sivan also said that if these satellites meet quality standards, ISRO will launch them. URSC chairman M. Annadurai said the objective of the training programme is to enable students from countries that have limited knowledge or exposure to small satellites to build them efficiently. Each participating country is expected to nominate two students: A mechanical engineer and an electrical engineer. They will be selected in batches of 30 each year, from 15 countries, and split into three teams of 10 students.

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ISRO will work in conjunction with the trainees. Functioning nanosats will be launched by the Satish Dhawan Space Centre on PSLVs and will hold payloads developed independently by ISRO itself. In the past, ISRO has guided the realisation and launch of five student satellites, all from India, and has also conducted satellite training programmes for 19 developing countries.

worldtimedate [ http://www.world-timedate.com/ ]
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Static fire photo

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"SpaceX Completes Successful Static Fire Test of Reused Falcon 9 Rocket for NASA Resupply Launch to ISS" @SpaceX #Falcon9 @NASA #CRS15 @Space_Station @elonmusk . Read my story plus static fire/water spout pics @ken_kremer spaceupclose.com
kenkremer.blogspot.com/2018/06/spacex…

https://twitter.com/ken_kremer/status/1010758528750047233
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SpaceX BFR - Earth to Deep Space / Re: Building BFR
« Last post by daveklingler on Today at 06:47 AM »
Lots of talk of autoclaves here. For something this massive, anyone sane would be looking at out-of-autopclave  processes. This ranges from dry-layup with prepreg CF (using low-temperature bonding), dry-layup with non-prepreg resin sheets (laid in-between CF layers, heat of the oven melts it to infiltrate and bond the layers), or dry-layup with resin infusion (probably not for something this large and strength-critical). All these processes are common in that they do not use an autoclave just a 'low temperature' oven (generally anywhere from 80°C to 180°C depending on resin), they use a single-piece mould with vacuum-bagging (avoids a costly multi-piece mould), and retain the strength, weight, and low-defect benefits of pre-preg over wet-layup. Modern OOA pre-preg does not even require the store-to-tool refrigeration that it once did, eliminating that cost too.

Out-of-autoclave is not the automatic answer for primary structure that is designed for many reuses. There must be a good reason composite aircraft wings and fuselages use massive autoclaves and not out-of-autoclave prepregs. If they do go with an OOA process it would almost certainly just be a typical oven-cured prepreg like what is currently used for fairings and interstages, not a resin infusion or separate resin sheet layup (I’ve never heard of that).
Everyone not building on an existing line designed decades ago is moving away from autoclaving when they can. e.g. the LM X-55 Advanced Composite Cargo Aircraft, Boeing Phantom Eye, Solar Impulse 2, Irkut MC-21, Cirrus SR-22, JASSM, CH-47 forward pylon replacement, 787 pressure bulkhead and control surfaces, etc.

What about the 777X wing though? That is a new line, built in-house by Boeing, and uses massive autoclaves. I have to think that Boeing had a good reason for doing that. My guess is that it has something to do with the possible void content in the OOA laminate and fatigue considerations. But that’s just pure speculation.

It's likely that fabrication processes for 777x were locked in by 2014, and planned a few years earlier. Once a process has been approved by the FAA and it's part of Boeing's internal engineering practice, not to mention their subs, there would have to be a very good reason to make any changes. The significant schedule risk and engineering changes involved could both threaten the company, not to mention external bureaucracy, so they stick with what works.

IOW, Boeing has already been through enough grief with the 787 and knows better than to go looking for more.

All of the extant OOA processes can now come very close to the same resin-fiber ratios that can be achieved with prepregs, which was a big issue even 10 years ago. Voids aren't really an issue if everything's done correctly, but weight and consistency of other engineering properties are. It's a big challenge to develop a repeatable, exact, consistent process that your engineers can count on and your floor workers can get perfect day after day without fail for an entire product lifetime. A 1% weight difference  in a vacuum infusion layup caused by a fill-in worker's difference in technique, or a slight shift in ambient room temperature, or a worn vacuum pump seal, etc. can cause big-time weight and balance problems in an airliner or control and navigation problems in a rocket.   All the big aerospace companies have solved these problems, but the solutions require methodical caution.

It'll be interesting to see what SpaceX finally uses, or even what they make themselves for the first few years. The size of BFR may require quite a bit of experimentation before they get their processes down.
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No news so we'll say it's been delayed to June 27 around 03:30 UTC
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SpaceX BFR - Earth to Deep Space / Re: Building BFR
« Last post by meekGee on Today at 06:24 AM »

Do they even have room for a big enough autoclave in the tent?  I'm assuming they are assembling the test BFS there in its entirety and it's not just for testing certain parts of the production prior to the factory being built.

Is it really so time-consuming to build an autoclave and then put up a 65,000 square foot hangar around it?

Boeing's 9m diameter autoclave took over 65000 man hours to build, so quite time consuming /labour intensive for the size of it.

http://www.aschome.com/index.php/en/asc-completes-worlds-largest-autoclave

And you just know that 9 m is just a temporary step back from 12 m... 

Boeing invests in tooling to run a production line for decades.  SpaceX in 10 years will have moved on from BFR to the RBFR.
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Just saw Tiangong 2 over Auckland, traveling from North-West to South-West. No additional glints or flares this time. It was about 60 seconds later than Heavens-Above prediction. But also strangely enough; saw another spacecraft traveling almost perpendicular to Tiangong 2: wasn't visible as long, but it was much brighter. According to Heavens-above; there are a whole host of Sats coming over as I'm typing this! Better put on a warm hat and go outside... ;)
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Space Science Coverage / Re: JAXA Hayabusa2 Mission : General Thread
« Last post by yoichi on Today at 05:44 AM »
https://twitter.com/haya2e_jaxa/status/1010759732515098625

[email protected]‏ @haya2e_jaxa

Our 8th Trajectory Control Manoeuvre (TMC08) for optical navigation was made on June 24, 2018 from ~09:30-09:40 JST. Trusters gave a velocity change of ~0.2cm/3 (+y), 2cm/s (+z). The distance to Ryugu from Hayabusa2 was 38km & the relative speed after TCM08 was ~0.08 m/s (8 cm/s)
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SpaceX BFR - Earth to Deep Space / Re: Building BFR
« Last post by Cheapchips on Today at 05:43 AM »

Do they even have room for a big enough autoclave in the tent?  I'm assuming they are assembling the test BFS there in its entirety and it's not just for testing certain parts of the production prior to the factory being built.

Is it really so time-consuming to build an autoclave and then put up a 65,000 square foot hangar around it?

Boeing's 9m diameter autoclave took over 65000 man hours to build, so quite time consuming /labour intensive for the size of it.

http://www.aschome.com/index.php/en/asc-completes-worlds-largest-autoclave
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Indian Launchers / Re: NavIC/IRNSS discussion
« Last post by worldtimedate on Today at 04:56 AM »
India's desi GPS 'NavIC' all set to navigate you

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Soon, your smartphones and car navigation systems may take directions from NavIC, the government's desi global positioning system (GPS) that has been developed to challenge the current GPS system of the West.

NavIC, an ambitious project pursued by the Modi government, is in the final stages of launch, and could soon be offered as an Indian counter to foreign systems currently being used by companies and other users.

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Sawhney said that the smartphones that are currently being sold in the country depend on foreign GPS systems. "Once we are officially there, the NavIC can be embedded on chips and other devices as well as on vehicle navigation systems."

With seven satellites, the NavIC covers only India and its surroundings and is considered to be more accurate than the American system. NavIC will provide standard positioning service to all users with a position accuracy of 5 metre. The GPS, on the other hand, has a position accuracy of 20-30 metre.

Even more remarkable for Indian scientists is that NavIC is technically superior to the American GPS. "Our system has dual frequency (S and L bands). GPS is dependent only on L band.

worldtimedate [ http://www.world-timedate.com/ ]
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I'm afraid my Chinese launch watching skills are not very good. The only places I know to check are Spaceflightfans.cn and CCTV13. No news on either of sites.

http://www.spaceflightfans.cn/event/long-march-2c-rocket-launch-yaogan30-05-satellite?instance_id=1665
http://tv.cctv.com/cctv13/
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