explain xkcd - User contributions [en]

2148: Cubesat Launch

2019-05-10T19:19:34Z

Hopsj: /* Explanation */

{{comic
| number = 2148
| date = May 10, 2019
| title = Cubesat Launch
| image = cubesat_launch.png
| titletext = Luckily, the damages were partly offset by the prize money we got from accidentally winning the nearby water skiing championship tournament.
}}

==Explanation==
{{incomplete|Created by a Launch Accident Investigator. Please mention here why this explanation isn't complete. Do NOT delete this tag too soon.}}

The comic begins with Megan telling Cueball that being officially part of a {{w|CubeSat}} launch is very expensive, but she has an idea for a much cheaper alternative: use a fishing line on a drone to attach to a rocket just before launch, with the cubesat attached to the other end of the fishing line so it gets pulled into space.

In reality, this plan would fail for multiple reasons.

1. Security would presumably prevent the drone from reaching the rocket.

2. The drone would not be able to attach itself to the rocket in a way that would remain secure.

3. The fishing line would not hold - either the rocket exhaust would sever it, or the force from the cubesat, from gravity plus the acceleration of the rocket, would become more than its tensile strength could withstand.

4. Precise weight is an EXTREMELY important number during launch. The extra weight of the drone, the fishing line, the air drag from the drone, and the cubesat all would combine to put more downward force on the rocket. This unexpected extra weight would not have been calculated during fueling the rocket and the rocket may run out of propellant before achieving the planned orbit.

Whatever her plan was, the plan goes wrong almost immediately. The unexpected force on the rocket from the side causes it to tilt and go off course, perhaps due to the unaccounted force causing bias or instability in the rocket's control system. Perhaps if the rocket's control software employed adaptive control techniques[https://en.wikipedia.org/wiki/Adaptive_control], it could have maintained control in the presence of the unexpected force. Megan and Cueball get tangled in the fishing line and are carried away. It is implied that the rocket crashes not long after. Megan and Cueball miraculously survive and are brought to an investigative board to explain their actions. Megan attempts to defend herself using flawed logic: something was bound to go wrong sooner or later, so it's not my fault that I was the cause.

The title text describes that the supposedly huge damages they caused were partly covered by the earnings from a water skiing championship, which Cueball and Megan presumably won by being dragged across the water by the rocket.

==Transcript==
{{incomplete transcript|Do NOT delete this tag too soon.}}
Megan: A spot on a cubesat launch costs a lot, but you can get a drone and a spool of fishing line for cheap.
Cueball: Uh oh.
''Next panel: wide shot. Megan is flying the drone.''
Megan: No, watch. This is gonna go great.
{{comic discussion}}

2148: Cubesat Launch

2019-05-10T19:18:02Z

Hopsj: /* Explanation */

{{comic
| number = 2148
| date = May 10, 2019
| title = Cubesat Launch
| image = cubesat_launch.png
| titletext = Luckily, the damages were partly offset by the prize money we got from accidentally winning the nearby water skiing championship tournament.
}}

==Explanation==
{{incomplete|Created by a Launch Accident Investigator. Please mention here why this explanation isn't complete. Do NOT delete this tag too soon.}}

The comic begins with Megan telling Cueball that being officially part of a {{w|CubeSat}} launch is very expensive, but she has an idea for a much cheaper alternative: use a fishing line on a drone to attach to a rocket just before launch, with the cubesat attached to the other end of the fishing line so it gets pulled into space.

In reality, this plan would fail for multiple reasons.

1. Security would presumably prevent the drone from reaching the rocket.

2. The drone would not be able to attach itself to the rocket in a way that would remain secure.

3. The fishing line would not hold - either the rocket exhaust would sever it, or the force from the cubesat, from gravity plus the acceleration of the rocket, would become more than its tensile strength could withstand.

4. Precise weight is an EXTREMELY important number during launch. The extra weight of the drone, the fishing line, the air drag from the drone, and the cubesat all would combine to put more downward force on the rocket. This unexpected extra weight would not have been calculated during fueling the rocket and the rocket may run out of propellant before achieving the planned orbit.

Whatever her plan was, the plan goes wrong almost immediately. The unexpected force on the rocket from the side causes it to tilt and go off course, perhaps due to the unaccounted force causing bias or instability in the rocket's control system. Perhaps if the rocket's control software employed [[adaptive control techniques]], it could have maintained control in the presence of the unexpected force. Megan and Cueball get tangled in the fishing line and are carried away. It is implied that the rocket crashes not long after. Megan and Cueball miraculously survive and are brought to an investigative board to explain their actions. Megan attempts to defend herself using flawed logic: something was bound to go wrong sooner or later, so it's not my fault that I was the cause.

The title text describes that the supposedly huge damages they caused were partly covered by the earnings from a water skiing championship, which Cueball and Megan presumably won by being dragged across the water by the rocket.

==Transcript==
{{incomplete transcript|Do NOT delete this tag too soon.}}
Megan: A spot on a cubesat launch costs a lot, but you can get a drone and a spool of fishing line for cheap.
Cueball: Uh oh.
''Next panel: wide shot. Megan is flying the drone.''
Megan: No, watch. This is gonna go great.
{{comic discussion}}

2148: Cubesat Launch

2019-05-10T19:12:55Z

Hopsj: /* Explanation */

{{comic
| number = 2148
| date = May 10, 2019
| title = Cubesat Launch
| image = cubesat_launch.png
| titletext = Luckily, the damages were partly offset by the prize money we got from accidentally winning the nearby water skiing championship tournament.
}}

==Explanation==
{{incomplete|Created by a Launch Accident Investigator. Please mention here why this explanation isn't complete. Do NOT delete this tag too soon.}}

The comic begins with Megan telling Cueball that being officially part of a {{w|CubeSat}} launch is very expensive, but she has an idea for a much cheaper alternative: use a fishing line on a drone to attach to a rocket just before launch, with the cubesat attached to the other end of the fishing line so it gets pulled into space.

In reality, this plan would fail for multiple reasons.

1. Security would presumably prevent the drone from reaching the rocket.

2. The drone would not be able to attach itself to the rocket in a way that would remain secure.

3. The fishing line would not hold - either the rocket exhaust would sever it, or the force from the cubesat, from gravity plus the acceleration of the rocket, would become more than its tensile strength could withstand.

4. Precise weight is an EXTREMELY important number during launch. The extra weight of the drone, the fishing line, the air drag from the drone, and the cubesat all would combine to put more downward force on the rocket. This unexpected extra weight would not have been calculated during fueling the rocket and the rocket may run out of propellant before achieving the planned orbit.

Whatever her plan was, the plan goes wrong almost immediately. The unexpected force on the rocket from the side causes it to tilt and go off course (although it is virtually impossible that two people could exert enough force with their hands and fishing wire to tilt a rocket weighing hundred of tons and with rocket engines putting out hundreds of thousands of pounds of force). Megan and Cueball get tangled in the fishing line and are carried away. It is implied that the rocket crashes not long after. Megan and Cueball miraculously survive and are brought to an investigative board to explain their actions. Megan attempts to defend herself using flawed logic: something was bound to go wrong sooner or later, so it's not my fault that I was the cause.

The title text describes that the supposedly huge damages they caused were partly covered by the earnings from a water skiing championship, which Cueball and Megan presumably won by being dragged across the water by the rocket.

==Transcript==
{{incomplete transcript|Do NOT delete this tag too soon.}}
Megan: A spot on a cubesat launch costs a lot, but you can get a drone and a spool of fishing line for cheap.
Cueball: Uh oh.
''Next panel: wide shot. Megan is flying the drone.''
Megan: No, watch. This is gonna go great.
{{comic discussion}}