The L-39 is a single-engine advanced trainer used by many of the world's air forces, and as such it has many of the design features and handling characteristics as the high-performance fighters that its students will one day fly. The cockpits are fully pressurized, heated and air-conditioned. Each of the tandem cockpits is equipped with enough flight controls, flight instruments, engine gauges, and system status indicators to allow either pilot to safely operate the airplane. As with most military jet trainers, the back seat was designed for instructors and, like many modern trainers, there is limited or no access to certain controls and switches in the rear "pit." In the L-39, these items include environmental controls, fuel pump switches, and the normal electrical controls. Also, the rear seat occupant cannot monitor the Exhaust Gas Temperature (EGT) simultaneously with the front-seater. In actual practice, none of these factors is a problem. There are duplicates of the really important controls in the back (and who really needs all that stuff, anyway?) The back seater does, however, have a few unique items to himself: a fiendish array of levers and switches which allow him to fail the front-seater’s instruments at will -- a holdover from the airplane’s days as a military trainer.