to estimate the size of unknown elements in the panel. Accuracy will vary depending on the quality of the photo located, the angle the shot was taken from, etc. However, this can give a good guideline on dimensions in situations where there may be no other source of information. The level of functionality will also vary within the 'pit'. Very realistic-looking pits may have nonfunctioning instruments, simply in place to complete the 'feel' of the cockpit. At the top end of realism would be individual real instruments, either modified from actual aircraft components or replicated. This approach provides the maximum immersion, but presents a dramatic increase in building complexity, with interface electronics needing to be fabricated and the associated software drivers needing to be written. A compromise between the two is to display the instruments on a monitor and mount this behind the panel. The simulated instruments can then be seen through the cutouts which can give a realistic effect, especially if the aircraft uses 'glass cockpit' displays in real life. Many pit builders go through the process of building a basic, low-spec compromise pit first, just to give them a dedicated environment to practice their hobby. The lessons learned in this process can be put to good use if they later decide to build a high-spec compromise or replica pit, which requires a great deal of time, effort, and passion to complete. General aviation Home based simulators have been a common training aid for private pilots for many years. Recently, the increased power of home PCs and improvements in graphics and simulation technology has opened up further opportunities to use a PC as a training aid. In fact, it is now quite easy to achieve a very high-fidelity training experience in one's own living room using off-the-shelf commercial products. While early simulators allowed instrument approaches to be practiced, with photographic scenery add ins pilots can now practice visual flights and navigation. Rehearsing a flight in the PC, before performing it in the real world, making training sessions in the real aircraft more productive. Recognizing this market, a number of suppliers provide ready-to-go desktop simulation products. Radio stacks, instruments, yokes, pedals, throttle quadrants, and seats are readily available from pilot shops. This allows a highly realistic GA cockpit to be put together in a matter of minutes. However an enthusiast is likely to extend well beyond the functional cockpit a