Body language maintain a certain amount of physical space between the other person. Tone of voice is a combination of spoken language and body language. The manner in which something is said can affect how it should be interpreted. Shouting, smiling, irony and so on may add a layer of meaning which is neither pure body language nor speech. Human communication is extremely complex and one must look at the whole in order to make any determination as to the attitudes being expressed. Body language is a major contributor to the attitude a person conveys to others. Albert Mehrabian maintains that during
Wide-body aircraft wake turbulence is generally related to the weight of an aircraft, these categories are based on one of four weight categories: light, medium, heavy, and super. Due to their weight, all current wide-body aircraft are categorized as "heavy", or in the case of the A380 in U.S. airspace, "super". The wake-turbulence category also is used to guide the separation of aircraft. Super- and heavy-category aircraft require greater separation behind them than those in other categories. In some countries, such as the United States, it is a requirement to suffix the aircraft's call sign with the word "heavy" (or "super") when