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62

The boosters do not have the range to get to Africa because they aren't going fast enough. If you look at the graphic below it shows a Falcon Heavy mission. The side boosters do not get very far downrange at all so they return to the cape. The drone ship for the core booster was located 1236km downrange, Africa is over 6000km downrange. The graphic came ...


39

It would only make sense to keep the fairing attached if the stage it was attached to was going to be recovered. The SpaceX falcon and falcon heavy are multi-stage rockets, only the first stage is reusable. The fairing is jettisoned once the aerodynamic pressure is low enough it isn't needed anymore, which is before orbital velocity is reached. Because it's ...


25

The fairings are detached to prevent carrying their un-necessary mass to orbit. This typically happens during the second stage burn. See this question for information about the timing of fairing jettion: How strong and "hot" is the wind on the payload after the fairing is deployed at ~110km? An image showing the fairing separation during the ...


23

In addition to the other answers, a fixed site in Africa would limit the available launch inclinations to a narrow band. A ship can be positioned anywhere in the ocean.


19

Aside from the technical aspects, Africa is comprised of a couple of dozen different countries, all with their own rules and politics, but none of which would appreciate a botched booster landing in their urban centers. Even one incident like this would be enough to make sure no more flights happen.


12

We saw with the Falcon Heavy third flight (STP-2 mission) that the center core landing was attempted at 1240KM from launch, which is the farthest recovery attempt to date. A consequence of the farther distance is that the speed of the core at separation is higher, which requires more fuel to slow down for the re-entry burn. It appears they did not ...


11

Apart from the mass penalty of carrying the fairing through the entire flight that Organic Marble mentioned, a hinged fairing and the mechanism to open and close it would be much more expensive, massive, and unreliable than the simple spring or explosive ejectors used on current rockets. You don't want to get the upper stage all the way into orbit and then ...


10

Yes! The current status (end of June 2019) according to a SpaceX statement via Michael Sheetz is: 45 in final orbits 5 still raising, in final orbits shortly 5 paused during raise for adjustments, will continue 2 intentionally being deorbited to show debris disposal 3 stopped communicating, "passively" deorbiting


9

There is likely minimal effect. At rocket speeds, there is very little effect of shear stress, the only significant effect is particles hitting the leading surface of the rocket. Also due to how fast hey are going, the effect of the rocket of "pushing air out of the way" does not have time to get far ahead of the rocket, and this drops further behind as ...


8

The landing approach for land and drone used by SpaceX targets a safe location, NOT the actual landing location for almost the entire landing event. It is only in the last few seconds, when the computer decides all is well that it diverts to actually hit the proper landing spot. This makes perfect sense. Aim away from your valuable landing location, until ...


6

If the boosters were closer together, like at separation, there is a complex interplay of shockwaves that produces lots of turbulence. If the vehicles stay in each other’s turbulence, it will need to be corrected for by the guidance system, probably using up more RCS fuel. These boosters are far enough apart during descent that they are outside of each other’...


5

The Falcon User manual provides some information: 4.5. Mission Accuracy Data As a liquid propellant vehicle with restart capability, Falcon 9 provides the flexibility required for payload insertion into orbit with higher eccentricity and for deploying multiple payloads into slightly different orbits. Until verified by actual operations, SpaceX ...


5

why not have them simply open, eject the payload, then close again, via a hinge mechanism? Because NOTHING is EVER simple when: accelerating to 17,000 mph, vibrating like mad, and performing an intricate dance among hundreds -- or even thousands -- of moving parts. KISS and blow off what can be blown off.


4

As Elon Musk explains Spacex is considered "Advanced Weapons Technology" by the America Gov, so limits employees to American citizens, I suspect this also limits where they are allow to land them.


3

I suspect that the main reason is this: The number one priority is to deliver the payload. Everything else is subordinate to this imperative. Putting hinges and doors on the fairing adds a layer of complexity -- what if the doors don't open? You've lost the payload. Much better to lose the fairing! That's only $6 million! So they do try to recover the ...


2

The Falcon 2nd stage has 4 Draco (hypergolic) thrusters. In addition to the reflections you point out, their firing also illuminates the 2nd stage engine bell (and puffs dents in the engine cover blanket). I can't find a source that shows their actual location however -- can someone help?


2

The axial vs radial deployment doesn't really matter. If they are released at different orientations or at a different rate of rotation: the satellites will have slightly different velocities and will drift apart. This is important as no kind of maneuvering or even reorientation is particularly safe with satellites in the near touching conditions they are ...


1

PP is to vent the propellant from the spacecraft to prevent it exploding which could cause clouds of debris that can potentially damage other satellites. (https://en.wikipedia.org/wiki/Passivation_(spacecraft)). It's a routine in modern rocket launches since debris issues are getting more severe and could harbor bigger disasters if there's a 'bomb' like ...


1

As mentioned in previous answers, BFR should be able to bring Hubble back. One issue with BFR's multiplanetary configuration is that it is meant to be multiplanetary. Even if it's a great system to go to the Moon or Mars, it is not optimized for Earth. (Even if there are plans/teasers for Earth to Earth transportation using BFR) Tyranny of rocket equation ...


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