system
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human
[Star Wars] How often did a space craft catastrophically fail and crash into a major population center of a planet?

With all the different kinds of craft and units of measurement/standards of quality, shouldn't craft be crashing into planets on a daily basis? Especially major population centers on heavily populated planets? How often did this happen?
gpt
Most planets have some form of local government who is responsible for coordinating landing times and zones , much like our Air Traffic Control at airports. 

In the Legends EU, arrival at any civilized planet is preceded by a comm-link with the local government who provides an orbiting trajectory, approach coordinates, and designated landing zone based on your purpose of visit and your socio-economic status. 

One simply enters this information into their NavCom (Navigation Computer) and the system determines the necessary speed and velocity for a safe approach. These systems will convert any non-Standard units into the necessary units to maintain safe approach. In some ships where the NavCom hasn't been properly maintained or that are too small to carry an onboard NavCom, an astromech droid would have the same responsibilities. 

So really, unless the NavCom/astromech is non-functioning, a crash is highly unlikely. In the case where one may occur, a highly populated planet would also have a dedicated anti-crash system, some combination of ships with tractor beams, or planet-side tractor beams, as well as a rudimentary forcefield that may be enabled when a crash is unavoidable. 

Crashes are more likely on unpopulated planets who cannot afford a proper government control over approach, but this is not always true as many large-scale pirates (ie. Those capable of settling on a dense scale on an otherwise underpopulated/uncivilized planet) will also have similar approach coordination.