Simulation cockpits or simpits are environments designed to replicate a vehicle cockpit. Although many pits commonly designed around an aircraft cockpit, the term is equally valid for train, spacecraft or car projects. 'Simpit' is generally used to refer to amateur, home built, setups which are the focus of this article. For more information on commercial flight simulators please see Flight Simulator. Aircraft simpits By their very nature, aircraft cockpits tend to have complex controls, instrumentation, and radios not present in other types of simulation. Recreating these present specific additional challenges to anyone building a cockpit. Aircraft components are often expensive to purchase, and access to real aircraft cockpits is likely to be restricted due to security concerns, especially in the wake of the 9/11 attacks or if the builder has chosen a current military aircraft. A way to avoid a lot of the pitfalls is to not replicate a specific aircraft, simply a class of aircraft. Thus creating a generic GA, airliner, or military cockpit, which while it will not have every button or switch of the real aircraft, will have all the key elements for simulation. The other end of the scale is to build an exact 1:1 replica of the real cockpit, using real panels or even a complete cockpit from the chosen plane. All cockpit builds will be somewhere between these two concepts, and even highly accurate replica pits will often make some concessions, if only due to limitations of the simulation software driving them. For replica pits, the choice of aircraft will be key. With the growth of home cockpits, there are a number of companies who sell complete kits for common aircraft, and the details of current Airbus and Boeing aircraft panels are fairly easy to obtain. For older aircraft, museums or scrap yards can be valuable sources of information. However, while research will often locate a lot of information, sometimes it is a minor detail that is needed. For example, how wide the center pedestal is, how large it should be, or its relative placement in the pit. Where the information is not in the public domain, more subtle techniques have been developed to obtain the information. For example, pixel counting from a digital photo of the aircraft. By counting the pixels in an item of known size, for example, a standard cockpit instrument, a scale can be established. This can then be used