The rationale used most frequently by the Department of Defense for the SR-71's termination was financial. The Blackbird's operation and maintenance costs were very high. Furthermore, they argued, imaging satellites could now conduct world-wide surveillance more efficiently and less expensively than manned reconnaissance aircraft. Independant aerospace analyst's, however, deflated this argument somewhat by pointing to the unique advantages aircraft bring to the reconnaissance arena. Aircraft for example are inherently flexible and unpredictable.
Aircraft have wide choice of routes, so tracking ships are unlikely to see it on the way in.
Thus it appears plausible that aircraft may still have a role in global reconnaissance. It would carry a crew of two and use a synthetic aperture radar with real-time downlink for reconnaissance. It is suggested that this type of platform could be very responsive, much more easily maintainable than the SR-71 and could deliver imagery of most points of interest within six hours of of the decision to go. A wide range of reports of observations of mysterious aerial phenomena have been associated with the Aurora aircraft. These observations are also in regards, consistent with the suggested Exotic Propulsion Aircraft.