Perferreds are carried on the corporate balance sheet in the shareholder's equity column, not the debt column.
Preferred stock has a fixed dividend rate, which makes it a fixed-income security. There are a couple of exceptions, however. For example, participating preferred stock may receive greater income under certain circumstances. Also, if the corporation is experiencing cash flow difficulties, the board of directors may withhold preferred dividends. So, though preferred stock typically has a fixed dividend, it isn't guaranteed. (See also: "What is the difference between preferred stock and common stock?")