3 ms·

Just to clarify: this is about insurance for the payload, not the booster. So, the insurance costs only depend on how likely the insurance company thinks it is

by 1958325146 6y ago

Just to clarify: this is about insurance for the payload, not the booster. So, the insurance costs only depend on how likely the insurance company thinks it is for the satellite to be blown up and how much the satellite costs, not how much the launch costs.

bumby 6y ago
Thanks for clarifying. That’s interesting because I would assume a reused structure (rather then reused design) would be at greater risk for failure. More fatigue cycles etc. I believe in the case of govt payloads they are self insured to around 80% or so but that’s obviously a different case. I also wonder if that affects the business plan for how to decide which payloads go on which rocket
- nickik 6y ago
  Well, when you get in a plane, would you rather it be the first or the 100s? There is basically a curve from where its more risk in the early launches and then gets better, as it nears end of live, risk goes up again.
  - bumby 6y ago
    Depends on what you mean. I’d like to be at or near the first flight of a new plane using a time-tested design. Failure rates (more specifically hazard rates) in most components tend to increase with time (I.e., follow a time-dependent failure model like a Weibull distribution and not a constant rate model). The “bathtub” curve is usually more associated with components with a constant failure rate (where the ideal place is after infant mortality but before wear out). There are two types of uncertainties here and I think we’re talking about different ones. One is a design uncertainty that can be mitigated using a well-used and understood design. The other is a component failure uncertainty which increases as service life increases. So the ideal place to be is in a well-vetted design with new-ish components.
    - nickik 6y ago
      I not arguing about design uncertainty, rather production uncertainty. A failure in the production is more likely to fail on the first flight then the 3rd.
      - bumby 6y ago
        I don’t think reliability theory, particularly in aerospace, supports this claim unless the quality control is lacking. To be fair, SpaceX has had quality issues in the past but they seem to learn quickly from it. To reiterate, the hazard rate tends to increase with service life. So as components age, there is an increased risk of failure.

bumby 6y ago

Thanks for clarifying. That’s interesting because I would assume a reused structure (rather then reused design) would be at greater risk for failure. More fatigue cycles etc. I believe in the case of govt payloads they are self insured to around 80% or so but that’s obviously a different case. I also wonder if that affects the business plan for how to decide which payloads go on which rocket

nickik 6y ago
Well, when you get in a plane, would you rather it be the first or the 100s? There is basically a curve from where its more risk in the early launches and then gets better, as it nears end of live, risk goes up again.
- bumby 6y ago
  Depends on what you mean. I’d like to be at or near the first flight of a new plane using a time-tested design. Failure rates (more specifically hazard rates) in most components tend to increase with time (I.e., follow a time-dependent failure model like a Weibull distribution and not a constant rate model). The “bathtub” curve is usually more associated with components with a constant failure rate (where the ideal place is after infant mortality but before wear out). There are two types of uncertainties here and I think we’re talking about different ones. One is a design uncertainty that can be mitigated using a well-used and understood design. The other is a component failure uncertainty which increases as service life increases. So the ideal place to be is in a well-vetted design with new-ish components.
  - nickik 6y ago
    I not arguing about design uncertainty, rather production uncertainty. A failure in the production is more likely to fail on the first flight then the 3rd.
    - bumby 6y ago
      I don’t think reliability theory, particularly in aerospace, supports this claim unless the quality control is lacking. To be fair, SpaceX has had quality issues in the past but they seem to learn quickly from it. To reiterate, the hazard rate tends to increase with service life. So as components age, there is an increased risk of failure.