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22
To give some idea of the sort of information people might want to get from a FTV this is a description of the 
X-5's telemetry setup.

It would be interesting to find out how many of the questions the X-15 collected data on are still relevant today. 

Obviously the FTV's goal is primarily to flight test the SABRE engine and its inlet, so I wouldn't expect it to have anything like the 590Kg (1300lb) allocated to flight test instrumentation the X-15 had. Most of this was prepared away from the aircraft and mounted onto an "elevator" pallet for installation into the instrument bay.

OTOH it is true that such hardware has become much smaller and lighter in the half century since the X-15 last flew. Although I'm not sure if a combined pressure and temperature sensor operating over the needed range exists. For this environment I think Low or High Temperature Cofired Ceramic would be a better technology than Silicon based MEMS. No one is going to be doing multi channel recording by deflecting light beams with mirrors onto film stock, when you can record onto a 32GB micro SD card today.

As for its construction one technique I'd not seen to help construct leading edges is the notion of prestressing them,  although it never seems to have been tried in practice it looks like quite a good way to save mass, especially given that carbon fibre was still a lab curiosity when the report was written.

Other potential design features would be making the body as a Sears Haack shape for minimal drag (as Skylon does) and possibly use winglets to lower drag further (as they won't have to withstand full reentry).
23
Historical Spaceflight / Re: Apollo Service Module Detail Images
« Last post by woods170 on Today at 08:24 AM »
For the level of detail that you desire, the book is indispensable.
Full 360 degree detail of every feature and protrusion.
For example, the service module is divided into 6 sectors surrounding a central helium tank.
Sector 1 is 50 degrees and contains scientific instruments.
Sector 2 is 70 degrees and contains propellant tanks.
Sector 3 is 60 degrees and contains propellants tanks.
Sector 4 is 50 degrees and contains fuel cells.

For the other sectors.....maybe you should bite the bullet and get the book! ;)

The book contains a visual and written description of the engineering behind both the SM and the CM. The visual description consists of 3D CGI based directly on the engineering blueprints for the CS and CM.
Generally, this is done correctly and to a high level of detail.
There is however one major error in the book: the proportions of the CM crew hatch. It is way off. Author acknowledged such some time after the book came out.
The book also contains lots of information about the materials used to construct both the CM and the SM. But the book holds substantially less information about coloring, let alone how the surfaces react to light. I might post one or two (partial) examples of pages from the book, to give you an idea. Will be several hours though, given that I'm away from home right now.
24
TESS downlink signal has been detected by UHF-Satcom and Scott Tilley (IMAGE re-discoverer):

https://twitter.com/uhf_satcom/status/987062005667385344
https://twitter.com/coastal8049/status/987094571560546304
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Please, pretty please, give us some measurements. Definitive to whatever accuracy your excellent rig allows! Just move to 10% of the time spent testing, and 90% spent improving the rig, from 100% spent improving the rig...
The hope is that these newest upgrades will allow for a more seamless integration with LabView....

OK, a true story, then I'll shut up.

Some decades ago I was a software performance specialist. I was asked to measure the performance of message routing software. It was important stuff, so I spent time writing scripts, automating procedures, testing what I'd done, and generally making sure I could reproduce the work at the touch of a button. After a few days I was still at it, but a senior engineer came to me, with the data he had wanted already in hand. He was at least two, probably three grades above me, the lead for dozens of engineers. "How did you do that?" I asked politely. "I just sat with a list of tests and executed all of them by hand, and used command line functions to measure resource usage. There were only a couple of hundred tests, it took about half a day.".

I'm sure you'll do a fantastic job, but the above is worth remembering.
26
Commercial Space Flight General / Re: Ripple Aerospace
« Last post by Steven Pietrobon on Today at 07:46 AM »
Thanks for your replies Nick!
27
Power system failure cost Isro GSAT-6A: VSSC chief

Quote
A failure in the power system could have led to the Indian Space Research Organization (Isro) losing contact with the recently launched GSAT-6A communication satellite, a senior official of the Vikram Sarabhai Space Centre (VSSC) said on Wednesday.

Quote
"We have already analysed and understood what could have gone wrong. The power system comprises the solar panel, battery and circuit. We assume a short has happened in the electrical circuit," VSSC director S Somanath said, adding that the protection circuits might not have become functional on time, leading to the damaging of wires.

Quote
Ruling out a possible sabotage, Somanath said that all systems were tested at various stages. He added that the scientists were still trying to control the satellite.

"We located the satellite immediately after the loss of contact, we are continuing to see the satellite, and we are trying to send some commands. But the satellite is tumbling, and is not under control. We hope that one day it will start receiving commands and we will be able to bring it to a safe mode. In the past, some satellites have responded after months of remaining out of contact," the VSSC director said.

Somanath said based on the GSAT-6A experience, additional precautions were being taken.

worldtimedate [ http://www.world-timedate.com/ ]
28
Not a surprise but good to know still on track, even if next launch has slipped to Q3:

Quote
SpaceX's Shotwell: Expect a 'couple more' Falcon Heavy launches this year
EMRE KELLY  |  FLORIDA TODAY Updated 3 hours ago

https://www.floridatoday.com/story/tech/science/space/2018/04/19/spacex-shotwell-expect-couple-more-falcon-heavy-launches-year/535071002/
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SNC Dream Chaser Section / Re: SNC Dream Chaser DISCUSSION Thread
« Last post by woods170 on Today at 07:22 AM »
He noted that there are no requirements under its NASA contract that require those cargo missions to fly on U.S. vehicles, citing NASA’s use of European and Japanese cargo vehicles to resupply the ISS.

I find this hard to believe, I think Orbital had to certify Antares contains enough US components to qualify as US launch vehicle when signing CRS1 contract. European and Japanese provided cargo vehicle in exchange for NASA sending their astronauts to ISS, I don't see how that is comparable to this situation.

Requirements changed between CRS 1 & 2. This may have been one of the changes. One can only assume that if SNC is spending the money to investigate foreign launch providers, that it must be possible.

I can tell you, based on source information, that your bolded IS in fact one of the changes.
30
SpaceX General Section / Re: TED talk by Gwynne Shotwell
« Last post by john smith 19 on Today at 07:19 AM »
FFR is great for missions to Eris, unfortunately, the power density is quite small, meaning it accelerates very slowly and can push a comparably minimal amount of mass, and burnout happens quite early as the reactor runs out of energy.
A million second-newton is a 20MW or so reactor.
I'd point out that typical NTR reactors were in the GW power range in the early 1970's.

I'd also note that for an Isp of 1000 000 you get a mass ratio of about 21 for 10% of C and once outside of a planetary gravity well its thrust is not that important. It will take a long while to accelerate to cruise speed.

Most importantly there has been very little serious effort on engineering a FFR.  I was merely pointing out no new physics are needed to do it, but the engineering is complex.
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