All Questions
34
questions
35
votes
3
answers
8k
views
What is the primary reason for SpaceX motion to have astronauts board Dragon before fueling up the rocket?
News piece: NASA supports SpaceX plan to fuel rockets with astronauts on board.
The move is criticized by many as unnecessarily dangerous.
From what I understand though, it shouldn't be necessary - ...
- 55.1k
5
votes
0
answers
219
views
What is the droplet size that is desirable for pintle injectors?
The pintle injectors tend to generate droplets after impingement of the fuel and the oxidiser stream and I understand that the droplets will be premixed.
In such a case, even a larger premixed ...
- 4,479
7
votes
4
answers
5k
views
Why is fuel cheap compared to rocket?
The fuel for a Falcon 9 (SpaceX) costs around \$200,000 per launch, while the launch itself costs \$62,000,000.
Safety precautions, rocket shell and rocket engines cost a lot. But why not fuel?
- 73
7
votes
1
answer
2k
views
Could the SpaceX Falcon 9 Block 5 work without sub-cooling the propellants?
I've been reading about some concerns about the densified (sub-cooled) propellants for Falcon 9 crewed missions in Spaceflight Now's article Lawmakers question safety, schedule for Boeing/SpaceX ...
- 1,778
5
votes
1
answer
418
views
Why did the "Secretive SpaceX Zuma Launch" make a big "S" or yin-yang shape in the sky?
The Space.com article Strange Sky Spiral May Come from Secretive SpaceX Zuma Launch shows images from this Tweet and this tweet, the second of which was posted by Dr Marco Langbroek (@Marco_Langbroek):...
- 149k
2
votes
0
answers
525
views
How much fuel is necessary for 2nd stage of Falcon 9 rocket to land?
What is the fuel mass nedeed for the 2nd stage of Falcon 9 rocket to land, how much compared with its total fuel mass that it has? Or how much delta-v is necessary? Would it be able for Falcon 9 to ...
- 2,145
4
votes
1
answer
4k
views
What is the spherical tank in this drawing of the BFS?
The big news in this article is the extremely large carbon-fiber fuel tank. However, the drawing in the article does not show it well. Instead what stands out like a sore thumb in the drawing is the ...
- 149k
6
votes
1
answer
268
views
Can Falcon 9's fuel be ignited by static discharge?
Reading Twitter comments about the recent Falcon 9 pad explosion, some postulated the problem was that a static discharge ignited the fuel as it was being loaded.
Since TEA-TEB is required to ignite ...
- 863
3
votes
0
answers
461
views
What could be wrong in the ground support equipment to cause the Falcon 9 AMOS on pad explosion? [closed]
The AMOS-6 mission Falcon 9 had a RUD (Rapid Unscheduled Disassembly) event on the pad, and it is initially postulated that it was related to fueling the second stage.
We know that SpaceX revamped ...
- 80k
0
votes
2
answers
2k
views
Falcon 9 fuel use [closed]
How much fuel does a Falcon 9 rocket used by SpaceX use, for a trip to the International Space Station?
Any possibility of Teslas batteries being used in the future?
4
votes
0
answers
99
views
What is the icy formation on these rockets? [duplicate]
I've sometimes seen icy formations form and break off of spacecraft. In today's SpaceX launch, there are a couple examples (times based on video) at 51:55 where you can see it growing:
Two similar ...
- 1,144
6
votes
1
answer
511
views
SpaceX Webcast - What is visible in this clip? [duplicate]
I've just watched the SES-9 Launch Webcast and was wondering what is visible at about 37:15?
Does the Falcon 9 have cameras in the kerosene (or LOX) tank?
- 163
11
votes
2
answers
922
views
How long can a vehicle stay fueled before the liquid oxygen gets too warm?
On February 28 2016, Falcon 9 attempted a second launch for its 22nd flight. However, it was put on hold for about 20 minutes at T-01:33 and had its countdown reset to T-11:44, giving a total of about ...
- 306
2
votes
1
answer
372
views
How much fuel remains in a booster such as the one used for Jason-3
Building off of this question, I am curious as to how much (just a simple magnitude of order) propellant remains inside a booster to cause such an explosion? Considering cost, I would expect very ...
- 2,941
15
votes
3
answers
6k
views
Is the supercooled LOX used in Falcon 9 Full Thrust a first?
One of the changes made to the Falcon 9 v1.1 Full Thrust was using supercooled liquid oxygen at 66 K (-340 F) as well as chilled RP-1.
I've seen various claims that this is a first in the industry. ...
- 773