While a lot has been accomplished, there are still many problems with the SATS plan. Although the price of air taxis will likely come down as the system matures and expands, they will initially be significantly more expensive than traditional air travel. At the outset, air taxis are likely to be worthwhile mainly for business travelers and others to whom saving time is worth the extra expense. However, the more they are used and the more that are available, the less they will likely cost per flight.
Another major problem is the question of safety. Will the new aircraft be safe? Will local airports be capable of safely handling the increased traffic? Both industry and government agencies have been addressing these issues. As they develop new aircraft, manufacturers have utilized the latest computer and electronic technology to increase the safety and reliability of their planes. Advances in navigation and air traffic control will also be necessary. At the demonstration in Danville, Virginia, NASA introduced a robotic air traffic controller capable of receiving requests to land from incoming planes and assigning them a number in line. Another system identifies each approaching aircraft by altitude, location and direction and shares this information with other aircraft in the vicinity. This is especially valuable for landings during bad weather, a significant problem for smaller airports.