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Apparently the copter was made with off-the-shelf parts. I wonder if I can cop a replica somewhere, and how it would fly considering it is built for martian ai

Apparently the copter was made with off-the-shelf parts. I wonder if I can cop a replica somewhere, and how it would fly considering it is built for martian air

kibwen 6y ago
Here's a really excellent video that answers all your questions: https://m.youtube.com/watch?v=GhsZUZmJvaM https://m.youtube.com/watch?v=GhsZUZmJvaM TL;DW: Martian atmosphere is so sparse that it's equivalent to flying at 100,000 feet on Earth. (The altitude record on Earth is 85,000 feet, set by the SR-71.) In order to fly at all the blades have to spin at nearly the (Martian) speed of sound. The drone wouldn't fly on Earth because the atmosphere is so dense that the blades would never make it up to speed.
- dralley 6y ago
  > (The altitude record on Earth is 85,000 feet, set by the SR-71.) The A-12 Arkangel flew higher (95,000 feet) and faster, but was short-lived and so highly classified that it doesn't hold any "official" records. And a MiG pilot flew up to 123,000 feet, but only on a ballistic trajectory, it wasn't a sustainable altitude.
ggreer 6y ago
If it was made with off-the-shelf parts then it's a testament to how wasteful NASA has become. Building that helicopter took them 6 years and $80 million.[1] 1. See page 20 of the launch press kit: https://www.jpl.nasa.gov/news/press_kits/mars_2020/download/mars_2020_launch_press_kit.pdf https://www.jpl.nasa.gov/news/press_kits/mars_2020/download/...
- vietjtnguyen 6y ago
  They can't exactly procure a bunch of parts and then call it a day. Lots of the cost is tied to the verification and validation. Then there's the system design, requirements engineering, trade studies, system integration, engineering models, simulation, software, environmental testing, launch costs, ground command and data systems, interfacing with the rover, etc. Paying engineers to do all that is what makes it so expensive.
  - ggreer 6y ago
    The $80M doesn't cover the launch costs. That would be part of the $2.4B for the overall rover project. For comparison: SpaceX's entire Falcon 1 program cost $90M over 6 years. That was to develop two new rocket engines (Merlin & Kestrel), build out the launch site on Omelek Island, and launch five times.
    - vietjtnguyen 6y ago
      Sure. I meant it more in the sense that there are some launch costs associated with the Mars Helicopter because it consumes mass budget. As to the SpaceX point. Yes, I think SpaceX is more efficient with their money than NASA, but this will boil down to a discussion of counterfactuals and degrees of "wastefulness". Was NASA wasteful? What does it mean to be wasteful? What's the threshold? What would it cost SpaceX to build the Mars Helicopter? Can we really compare a launch vehicle versus a tech demo of a rotorcraft operating on another planet? Would that $80M be better spent just funding SpaceX? I don't know. I just don't think it's fair to simply say "If it was made with off-the-shelf parts then it's a testament to how wasteful NASA has become". The engineering has to happen. Could NASA have been more efficient with it? Probably. Was it wasteful? I don't think so.
  - m4rtink 6y ago
    Yeah, with launch windows every two and hal years only, 9 months of travel time, still expensive launch costs and complicated landing requirements you really need to make sure stuff works. Sure, for stuff you can reasonably test in Earth gravity and atmosphere you can just weld stuff together in a field and then fly it until it stops crashing. Thats a case when you can iterate quickly and relatively easily with lots of COTS stuff.

Apparently the copter was made with off-the-shelf parts. I wonder if I can cop a replica somewhere, and how it would fly considering it is built for martian air

kibwen 6y ago

Here's a really excellent video that answers all your questions: https://m.youtube.com/watch?v=GhsZUZmJvaM https://m.youtube.com/watch?v=GhsZUZmJvaM TL;DW: Martian atmosphere is so sparse that it's equivalent to flying at 100,000 feet on Earth. (The altitude record on Earth is 85,000 feet, set by the SR-71.) In order to fly at all the blades have to spin at nearly the (Martian) speed of sound. The drone wouldn't fly on Earth because the atmosphere is so dense that the blades would never make it up to speed.

dralley 6y ago
> (The altitude record on Earth is 85,000 feet, set by the SR-71.) The A-12 Arkangel flew higher (95,000 feet) and faster, but was short-lived and so highly classified that it doesn't hold any "official" records. And a MiG pilot flew up to 123,000 feet, but only on a ballistic trajectory, it wasn't a sustainable altitude.

ggreer 6y ago

If it was made with off-the-shelf parts then it's a testament to how wasteful NASA has become. Building that helicopter took them 6 years and $80 million.[1] 1. See page 20 of the launch press kit: https://www.jpl.nasa.gov/news/press_kits/mars_2020/download/mars_2020_launch_press_kit.pdf https://www.jpl.nasa.gov/news/press_kits/mars_2020/download/...

vietjtnguyen 6y ago
They can't exactly procure a bunch of parts and then call it a day. Lots of the cost is tied to the verification and validation. Then there's the system design, requirements engineering, trade studies, system integration, engineering models, simulation, software, environmental testing, launch costs, ground command and data systems, interfacing with the rover, etc. Paying engineers to do all that is what makes it so expensive.
- ggreer 6y ago
  The $80M doesn't cover the launch costs. That would be part of the $2.4B for the overall rover project. For comparison: SpaceX's entire Falcon 1 program cost $90M over 6 years. That was to develop two new rocket engines (Merlin & Kestrel), build out the launch site on Omelek Island, and launch five times.
  - vietjtnguyen 6y ago
    Sure. I meant it more in the sense that there are some launch costs associated with the Mars Helicopter because it consumes mass budget. As to the SpaceX point. Yes, I think SpaceX is more efficient with their money than NASA, but this will boil down to a discussion of counterfactuals and degrees of "wastefulness". Was NASA wasteful? What does it mean to be wasteful? What's the threshold? What would it cost SpaceX to build the Mars Helicopter? Can we really compare a launch vehicle versus a tech demo of a rotorcraft operating on another planet? Would that $80M be better spent just funding SpaceX? I don't know. I just don't think it's fair to simply say "If it was made with off-the-shelf parts then it's a testament to how wasteful NASA has become". The engineering has to happen. Could NASA have been more efficient with it? Probably. Was it wasteful? I don't think so.
- m4rtink 6y ago
  Yeah, with launch windows every two and hal years only, 9 months of travel time, still expensive launch costs and complicated landing requirements you really need to make sure stuff works. Sure, for stuff you can reasonably test in Earth gravity and atmosphere you can just weld stuff together in a field and then fly it until it stops crashing. Thats a case when you can iterate quickly and relatively easily with lots of COTS stuff.