Especially if we include Experimental aircraft, there are many different makes and models from which owners and operation may choose, each of them having their own set of features. Whether we want an aircraft to perform aerobatics, do aerial application, conduct training or even engage in cargo operations, theres a model out there, somewhere, optimized for the mission. But all aircraft embody compromises: none literally can do everything.

For example, we can trade fuel for payload, but rarely can we have plenty of both. Likewise, airplanes optimized for short-field operations usually suffer reduced cruise airspeeds and/or restricted useful load when compared to others. And primary trainers can be good at a lot of things, but regular transportation in the IFR system isnt one of them. What does make for a good IFR airplane? What characteristics should it have, and which can be omitted?
