Systems that operate in extremely volatile environments, such as orbiting satellites, must be designed with a strong emphasis on fault tolerance. Rather than rely solely on the system hardware, it may be beneficial to entrust some of the fault handling to software at the application level, which can utilize semantic information and software communication channels to achieve fault tolerance with considerably less power and performance overhead. We show the implementation and evaluation of such a software-level approach, application-level fault tolerance and detection (ALFTD) into the orbital thermal imaging spectrometer (OTIS).