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Part of NASA's Mars 2020 mission, Ingenuity is planned for deployment in April 2021, about 60 days after landing with the rover Perseverance in the crater Jezero at Octavia E. Butler Landing on 18 February 2021.

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Why didn't Ingenuity (helicopter) deploy immediately right after rover landing?

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Why didn't Ingenuity (helicopter) deploy immediately right after rover landing?

For many reasons. Number one is that helicopter is an experimental (i.e., not mission-critical) item. Mission-critical aspects took a much higher priority.

Another reason is that Ingenuity deployment requires the Perseverance to move to a flat spot, drop the helicopter from its undercarriage, and then back away. Perseverance happened to land on a good spot for deployment, but that is a bit irrelevant as Perseverance didn't have the capability to back away right after rover landing.

That gets to the final reason, which is there's only so much room on Perseverance's limited data storage for programs. The main flight computer was used to guide the descent vehicle and the skycrane through the entry, descent, and landing process. The software that enables the rover to rove was not installed on the vehicle at the time of landing. JPL long ago developed the ability to upload new software to their remote vehicles. This takes time, lots of time.

Think of how much time it took you to download a program twenty years ago. Now multiply that by a large number. The overall upload takes place in pieces, and each upload has to be confirmed before it is put into place, with a twenty minute round-trip time. The overall process takes weeks to complete.

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    $\begingroup$ @user39728 Ingenuity is a technology demonstration experiment. It is not mission critical and as such it is not expected to do much except to fly. It will be a complete failure if it doesn't even take off. It will be deemed a marginal success if it takes off but crashes shortly later (but it will be written off for future missions). It will be deemed a complete success if it just once takes off and lands without crashing. The hope is that it will take off and land five times. Even if it succeeds just once, let alone five times, future Mars missions most likely will more capable helicopters. $\endgroup$ Mar 22 at 2:13
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    $\begingroup$ @GamerGypps Those 100 TB drives one can now buy wouldn't last very long in space. Perseverance's flight computer has 2 gigabytes of flash memory, 256 megabytes of DRAM, and 256 megabytes of EPROM. $\endgroup$ Mar 22 at 12:47
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    $\begingroup$ @GamerGypps, using a smaller process node means more vulnerability to radiation. So some of the same advances that make newer tech faster (high-capacity, high-density, etc) also make it more vulnerable. $\endgroup$ Mar 22 at 14:23
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    $\begingroup$ Note the non-critical parts of the mission do use newer technology: ingenuity uses a Snapdragon 801 (smartphone processor from 2014) and the EDL camera system used a commercial Intel Atom processor and 480 GB SSD. $\endgroup$ Mar 22 at 15:21
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    $\begingroup$ @GamerGypps When I started working in this field, spacecraft state of the art was five years behind, maybe ten years behind, earthbound state of the practice. Part of the problem is that because avionics design impacts so many other systems, avionics design decisions are made early on in the spacecraft design process. That alone accounts for perhaps five years. But now we're twenty years behind, and that's primarily because earthbound computing doesn't have to worry much about the severe radiation effects that plague computers that operate outside of the Van Allen Belts. $\endgroup$ Mar 22 at 16:17

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