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Rocket Lab / Re: Neutron vs F9R and SS
« Last post by edzieba on Today at 10:30 am »
The core premise that avionics are too expensive and purely open-loop guidance would be an acceptable alternative may have been true a few decades ago, for fixed-nozzle solid stages.
But today, for a liquid propellant stage, the sensors required are not of extreme cost - particularly as you still need the rest of the avionics suite for open-loop control, engine management, TVC, and other stage functions such as spinup, spindown, and seperation - and even if you decide that ring-laser gyros are too pricey, then your fallback is not 'no IMUs' but use of MEMS IMUs.

You're giving yourself a lot of new headaches, making your vehicle less reliable (the first stage now needs to perform absolutely perfectly as your upper stage has no capability to compensate), for a very tiny cost saving.
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Commercial Space Flight General / Re: Firefly Aerospace
« Last post by TrevorMonty on Today at 10:07 am »
I hope Firefly has her own section because is maybe will be an amazing company...
It might make sense to combine the NGIS and Firefly sections, since the new Antares will use basically the Beta first stage.
Buyout is only guess nobody from NGIS or Firefly have publicly said it will happen. For now they 2 separate companies.
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Spaceflight Entertainment and Hobbies / Re: Space Stamps
« Last post by salyut on Today at 09:45 am »
May 17, 1965, New Caledonia.
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Is there anyway to send a camera inside of the solid boosters to check the condition of the solid material?  This would tell if they need to restack and repair or replace the solid material.

No. Segment delamination since initial stacking that is sufficient to damage the propellant cohesion is not visible to the naked eye.
X-ray, ultrasonic and other non-invasive, non-destructive methods should be able to detect invisible changes,
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Commercial Space Flight General / Re: Phantom Space
« Last post by john smith 19 on Today at 09:25 am »
Checked the website.

So it looks like they want to be another Rocket Lab, in the sense of offering satellite launch and build.

Trouble is that niche has already been filled so it's hard to see what PS will offer that's better against an established player. Especially one that seems to have bought up the #1 providers in their market sector of specific satellite subsystems. IE panels, power systems, reaction wheels etc.

That said it could be that this is the one where Cantrell put's into practice the line of Tom Cruise's character that "Every failure is a dress rehearsal for success"  :)

Or not.  :( 

Time will tell.
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Ha. Thanks. I don't watch or listen to the NSF broadcasts so missed that. Seems like the simplest, least R&R/Cost way to do a mission like this. I still think if this goes ahead it will end up being two missions. One for boost and another (maybe) replacement of Giros.

Screen capture (cropped) from last night's NSF live showing @brickmack's rendering of Dragon forward thrusters boosting hubble
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Commercial Space Flight General / Re: Firefly Aerospace
« Last post by Star One on Today at 09:22 am »
I hope Firefly has her own section because is maybe will be an amazing company...
It might make sense to combine the NGIS and Firefly sections, since the new Antares will use basically the Beta first stage.
Id hope if NGIS do buy out Firefly they might keep it as a separate arms length entity rather than just absorbing it into the general NGIS brand.
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Too much focus on analysis and process above building and getting things done. Also, the tech we had then with rocketry was close to the optimal already (for expendables). And they had more money and wages were lower.

We don't need to spend a significant portion of our GDP on getting back to the Moon today. Even before SpaceX started re-using boosters and lowered the cost of getting to space, we could have designed our lunar exploration system around existing boosters and saved billions and got there a lot faster. Probably more sustainable too.
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If it's a plane, can they then forego the escape capsule as they can glide back to earth unpowered, unlike a rocket?
Historically most danger in rockeet launch is actually at launch. They could scrap the escape module plan if they felt their vehicle is safer than expendables.
Quote from: Halken
You assumed they got to 200 km/h with the sled? Would it not be possible to move that to 400 km/h and would that make any difference?
No I assumed they got 200 metres per second from the sled. The speed of sound at ground level is 340m/s
You can use the design game earlier in the thread to see what happens if you increase the takeoff speed right up to the speed of sound at ground level. That would produce a very loud sonic bang at ground level that would likely be heard for 10s of miles.
Quote from: Halken
They are working on the marginals I believe and since they have raised that kind of money and attracted astronauts they must have found a way where the marginals are enough in their favor. If it was easy everyone would do it.
It's not that much money for the task and I think it's mostly from investors who really want to do something without doing much in the way of due dilligence. 
If they had they'd have realized that the switch from LH2 (like RASV) to kero has major implications on implementability.

If they really have something then they will raise enough funds to execute something or license it to someone. Either will trigger product announcements or PR.

If they have nothing then the company will just disappear like so many before it.  :(

I have no special insight into them and I'm just going by their public statements. If they have been more forthcoming to their investors then they may have more reason to be optimistic. Based on their public statements this thing won't fly.  I could not find an aircraft that had the fuel fraction necessary to make this design possible.

That's not to say it's impossible, but it was beyond what IMHO is one of the most skilled CFRP design and build teams in the aircraft industry can manage. On a side not what the SABRE engine gives Reaction Engines is to build a winged vehicle at a structural fraction that is possible.  In effect SABRE allows you to afford to fit wings to a vehicle.

Do you have some special investment in Radian? You seem quite invested in their success.
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Screen capture (cropped) from last night's NSF live showing @brickmack's rendering of Dragon forward thrusters boosting hubble
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