[sokoloff]

The NTSB (not the FAA) handles the part of aircraft accident investigations that you're likely interested in. They then make recommendations to the FAA on matters of aircrew or aircraft certification or other deficiencies that were in the causal chain of the accident.

They also don't travel to the vast majority of aircraft accidents, even ones with fatalities. They do travel to jet (or airline turboprop) accidents with fatalities, but small general aviation aircraft crash fairly regularly with only a small portion of those crashes getting any meaningful investigation from the NTSB.