The United States has only had three major commercial airline disasters in over 10 years with respect to fatalities. The days of major disasters like TWA Flight 800 or the hijacked planes of 9/11 are over. The United States has done plenty to prevent commercial airline accidents. Airlines in South America, Asia and Africa are the ones we need to worry about.
Organizations like the DOT and the NTSB are enough to prevent airplane accidents because they work along side companies like Boeing to help airline safety. Often times when safety is in question, companies and the NTSB will ground a specific aircraft until the problem is resolved. Also, aircraft have inspection and mechanical minimums that require that they be serviced after an amount of hours in the air.
While the amount of flights keeps increasing weekly, the overall percentage of airplane-related accidents has remained the same or has gone down over the last 50 years. Currently, we are on pace to increase computer security and interconnectivity that will help air traffic controllers, airlines and pilots be safer in the air than ever before.
When it comes to preventing accidents dealing with planes this can take range a number of different things. One will always argue that not enough funding is being diverted to things dealing with planes to make sure they are alright that more and more needs to be done. However, how much is enough?