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Joined 1 year ago
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Cake day: June 13th, 2023

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  • Computer code is very complicated, so when humans write code we write in a way we can understand. We name functions and variables with names that make sense, and we put comments in the code so we can understand how it works.

    Compliers don’t care about any of those things. Variable names are turned into numbers, and comments are ignored.

    You can convert machine code back to source code, it will be missing all those human readable labels and explanations. You can recreate them, but its a major process. Reverse engineering is done sometimes, but there’s a reason is not common.

    There’s also the issue of licensing. An important part of free and/or open source software is that you have permission to modify the source code. You probably don’t have a license to use the code if its closed source. There are ways to do this legally but it adds extra hurdles and inconvenience to an already major process.


  • Her plane is worse than most. Its one of the last trijets in production. Planes with a small number of large engines are more efficient than planes with many small engines, which is why modern planes are all twinjets with wide high-bypass engines.

    Airlines care about fuel efficiency. A minor reduction in fuel burn results in increased profits, and they operate large fleets. A small increase in efficiency across an entire fleet is huge. If you own a private jet, you are spending huge amounts of money to have one, the cost of fuel would only be a minor concern.

    The solution to private jets is regulation. Private jets don’t need to exist. They don’t need to be replaced by another kind of airplane. The solution is to replace all planes on overland routes with electrified rail. Let the rich buy private railcars for transport.

    I’m not skeptical on the concept of small aircraft. I wanted to give context because very few people will picture bush planes and puddle jumpers from the mention of “commercial aviation.”

    PS: My calculations for fuel burn were based on comparing the range to the fuel capacity. Those are the numbers I have ready access. Planes are much less efficient when the tanks are full, and swift’s plane has a longer range, so it’s probably not quite as bad as my calculations indicate on comparable flights.


  • The carbon comes from the fuel. Burning a ton of jet fuel will release the same amount of carbon regardless of the plane that burns it.

    Taylor Swift’s plane is a Dassault Falcon 7X. It weighs around 17 tons and seats 12 to 16 passengers.

    Her plane burns 60% less fuel than a 737 MAX 8. However, her plane holds 9% of the passengers of the MAX 8, so its far less efficient per passenger than typical commercial aircraft.

    Private planes are not a huge contributor to carbon emissions in comparison to others. They’re bad, obviously. But there are far more commercial airplanes, and they fly much more frequently than private jets.

    Private jets get people’s attention. One person being directly responsible for that much carbon is notable is unconscionable. But it’s the scale of transportation overall that is the issue.






  • For context jet fuel is around 9,720 Wh/L. However, energy density(energy per volume) is less important in aviation than specific energy(energy per mass) as weight is far more likely to be the limiting factor.

    A standard lithium ion battery has 100-265 Wh/kg

    The article claims 500 Wh/kg in this new battery.

    Jet fuel has around 12,000 Wh/kg.

    Though this is a major improvement in battery tech, batteries are unlikely to ever improve to the point to even approach the energy storage of liquid fuels.

    Batteries cannot run commercial aviation as it currently exists. Battery planes will need to fly slower and shorter. There is no other way.






  • It works for the Cirrus because that plane is tiny. A parachute big enough to safely land a commercial jet is not feasible.

    If a commercial plane has a failure, say an engine failure as in the news story, the pilots with fly the plane with the other engine to a safe landing.

    If the Cirrus has an engine failure it becomes a glider. If there’s no airports nearby you’ll have to ditch in a field somewhere. There is a lot less redundancy in general aviation.

    If you’re a new pilot buying your first plane, having a parachute on the plane is a nice feature.