On October 1, 1993, at 1220 mountain standard time, a Cessna O- 2A, N5151A, experienced a partial loss of engine power to the front and rear engines during initial climb from the Ryan Field near Tucson, Arizona. The pilot made a forced landing in an open field about two miles east of the airport. The airplane was substantially damaged upon impacting the rough, desert terrain. The commercial pilot was not injured. The flight was originating at the time of the mishap. The pilot verbally reported that prior to the accident flight the airplane had been idle for several years. The pilot had been hired to ferry the airplane from Arizona to the southeast United States. In preparation for the flight, a contractor had performed limited maintenance on the airplane. According to the pilot, during takeoff the airplane's front engine suddenly lost power. Its rpm reduced from full power to about 1,600 rpm, and then the rear engine lost power. The fuel flow became "low and intermittent" and the airplane stopped climbing. The pilot further reported that because the engines' oil temperature and pressure remained in the normal operating range, he believed both engines had experienced fuel starvation. On October 7, 1993, a Federal Aviation Administration (FAA) airworthiness inspector verbally reported to the National Transportation Safety Board that its examination of the airplane revealed two of the front engine's six fuel injectors were found partially clogged with a foreign substance. The FAA inspector stated that the contractor had evidently not completely purged the airplane's entire fuel system during efforts at preparing the airplane for the ferry flight. In October of 1993 and in May of 1994, the pilot was requested to complete the required Safety Board "Aircraft Accident Report," NTSB Form 6120.1. When the Board receives the pilot's form, it will be appended to this report.