4 ms·

Hopefully without the added scent for leak detection. I'd assume for rocketry, they have more advanced methods of detecting leaks than our sense of smell.

thinkcontext 4y ago
Actually, there's probably a fair amount of relatively controlled leaking that goes on. There's a certain amount of boil off of the cryo temp methane. In the video of the launch you can see active flaring in the wide shot. And at various points plumes come off the rocket on the pad, that's venting through pressure relief valves.
- mabbo 4y ago
  Controlled release, but that's not leaking. When you release it, you burn it immediately so that a cloud of explosive gas doesn't build up. When it's leaking somewhere, that cloud is building up in an uncontrolled way in an unexpected place.
mabbo 4y ago
They probably do have better means to detect it, but why give up such a powerful and useful one as "every human being that goes anywhere near it can instantly detect it"? Mercaptan is incredible at what it does. A minuscule amount is noticeable by our noses.
xoa 4y ago
To this and sibling posts: as far as I know no, the methane used for rocketry is extremely pure and doesn't have any scent, nor indeed does natural gas getting moved around or used industrially. It's expensive as an additive, but more importantly sulfur is bad news for a big range of applications, and when it comes to engines in general let alone rocket engines combusters/injectors etc are not sulfur loving. Sulfur is bad in vacuum chambers too for that matter, gets into the walls and then the chamber is contaminated forever. This isn't just a methane thing either, it's an issue with traditional fuels. The formulation for RP-1 has changed significantly over time in that respect for example, from the original 500ppm down to 30ppm now. And if it was cheap enough and still mattered one reason rocketry and aerospace companies might be interested in synfuels beyond the environmental aspect is being able to have zero sulfur at all from the get-go.
- CuriousCosmic 4y ago
  While I don't disagree with you, the Terran 1 actually runs on LNG rather than pure methane. I'm not sure what type of constraints they place on the LNG that ends up in the rocket but to my knowledge it's not pure methane like the Starship or other methalox rockets.

thinkcontext 4y ago

Actually, there's probably a fair amount of relatively controlled leaking that goes on. There's a certain amount of boil off of the cryo temp methane. In the video of the launch you can see active flaring in the wide shot. And at various points plumes come off the rocket on the pad, that's venting through pressure relief valves.

mabbo 4y ago
Controlled release, but that's not leaking. When you release it, you burn it immediately so that a cloud of explosive gas doesn't build up. When it's leaking somewhere, that cloud is building up in an uncontrolled way in an unexpected place.

mabbo 4y ago

They probably do have better means to detect it, but why give up such a powerful and useful one as "every human being that goes anywhere near it can instantly detect it"? Mercaptan is incredible at what it does. A minuscule amount is noticeable by our noses.

xoa 4y ago

To this and sibling posts: as far as I know no, the methane used for rocketry is extremely pure and doesn't have any scent, nor indeed does natural gas getting moved around or used industrially. It's expensive as an additive, but more importantly sulfur is bad news for a big range of applications, and when it comes to engines in general let alone rocket engines combusters/injectors etc are not sulfur loving. Sulfur is bad in vacuum chambers too for that matter, gets into the walls and then the chamber is contaminated forever. This isn't just a methane thing either, it's an issue with traditional fuels. The formulation for RP-1 has changed significantly over time in that respect for example, from the original 500ppm down to 30ppm now. And if it was cheap enough and still mattered one reason rocketry and aerospace companies might be interested in synfuels beyond the environmental aspect is being able to have zero sulfur at all from the get-go.

CuriousCosmic 4y ago
While I don't disagree with you, the Terran 1 actually runs on LNG rather than pure methane. I'm not sure what type of constraints they place on the LNG that ends up in the rocket but to my knowledge it's not pure methane like the Starship or other methalox rockets.