On June 20, 2005, at 1130 eastern daylight time, a Cessna 182, N53538, registered to and operated by Cleghorn Aviation Incorporated, was reported missing 18 miles off the coast of Naples, Florida. The personal flight was operated under the provisions of Title 14 CFR Part 91 with an instrument flight plan filed. Instrument meteorological conditions prevailed at the time of the accident. The pilot has not been found, and is presumed to be fatally injured. The main wreckage has not been located, and is presumed to have sustained substantial damage. The flight departed Naples, Florida at 1100 on June 20, 2005. According to Fort Myers approach control, the airplane departed Naples Municipal Airport (APF) at 1100 on a cross-country flight to Key West International Airport. The pilot was transferred to Miami Center Control after departure from APF. The flight was cleared to 5000 feet by Fort Myers Approach and instructed to contact Miami air traffic control center (ARTCC). The pilot established radio contact with Miami Center at 1113 level at 5,000 feet. The controller acknowledged, issued the altimeter setting, and stated, " if you need to deviate for weather east of course is approved and just let me know if you need anything." At 1116, the controller transmitted alerts for convective SIGMETs 28E and 29E, warning of severe weather in the vicinity of Vero Beach, Miami, Sarasota, and Key West, as well as the Palm Beach area. At 1119, the controller transmitted, "N53538, if you need to deviate for east of course as you may need is approved." The pilot responded, "it doesn't look like it's gonna get much better - we're not having a bad ride here at 5,000." At 1121, the pilot requested to, " take it to the west just a little bit maybe direct Key West stay outside the warning areas." The controller missed the transmission and asked the pilot to repeat it. The pilot then requested direct Key West and stated that he believed he could stay outside the warning areas. The controller approved direct Key West, but again told the pilot that if he needed to deviate for weather it would have to be to the east because of the warning areas. At 1126, the pilot transmitted his call sign but no other message. The controller responded by clearing the flight direct to Key West and stating, "warning areas are cold, you're fine where you're at." There was no response from the pilot. At 1127, the controller cleared the flight to descend to 4,000 feet and issued the Key West altimeter setting. There was no response. The controller made several more unsuccessful attempts to reestablish contact between 1128 and 1132. Following the apparent loss of radar contact with N53538, the controller asked the pilot of ,N888JJ, a Piper Navajo flying at 6,000 feet five miles behind N53538, to look for the missing aircraft. Suncoaster 2 (SCC2), another Navajo, was at 7,000 feet approximately five miles behind N888JJ, also on a southbound track was asked to look for N53538 as well. During the period N888JJ was transitioning the area, the aircraft showed significant altitude excursions. After exiting the area, the pilot reported encountering "heavy" turbulence. Neither N888JJ nor SCC2 was able to provide any additional information on N53538. According to recorded radar display data, the aircraft entered an area of heavy thunderstorms. Review of pilot records revealed the pilot was issued a private pilot certificate on October, with ratings for airplane single-engine land, multiengine land. Review of records revealed that the pilot completed his instrument flight test on June 6, 2005. The pilot held a third-class medical certificate issued on June 10, 2005. Review of records indicated that the pilot accumulated a total of 322 flight hours. The pilot's logbook was not recovered for review. Review of records revealed that the last annual inspection was completed on August 2, 2004. Review of radar data revealed that the airplane disappeared off of radar approximately 18 miles south of Marco Island, Florida. During the search and rescue debris was located, it consisted of a passenger-briefing card, wheel assembly, seat back, and oxygen bottle, and the main wreckage was not located. FAA order 7110.65, "Air Traffic Control," paragraph 2-6-4, "Weather and Chaff Services," states: 2-6-4. WEATHER AND CHAFF SERVICES A. Issue pertinent information on observed/reported weather or chaff areas. Provide radar navigational guidance and/or approve deviations around weather or chaff areas when requested by the pilot. Do not use the word "turbulence" in describing radar-derived weather. 1.Issue weather and chaff information by defining the area of coverage in terms of azimuth (by referring to the 12-hour clock) and distance from the aircraft or by indicating the general width of the area and the area of coverage in terms of fixes or distance and direction from fixes. 2.Issue the level of echo intensity when that information is available. 3.When equipment limitations exist, controllers shall, at a minimum, ensure that the highest available level of echo intensity within their area of jurisdiction is displayed. 4.When a deviation cannot be approved as requested and the situation permits, suggest an alternative course of action. B. In areas of significant weather, plan ahead and be prepared to suggest, upon pilot request, the use of alternative routes/altitudes. {NEW-2004-12 1-1-3 Note Revised February 19, 2004} NOTE 3 states: Weather significant to the safety of aircraft includes such conditions as tornadoes, lines of thunderstorms, embedded thunderstorms, large hail, wind shear, microburst, moderate to extreme turbulence (including CAT), and light to severe icing. C. Inform any tower for which you provide approach control services if you observe any weather echoes on radar, which might affect their operations. The Miami Center is equipped with digital weather display capability that is designed to show levels 2 through 6 on the NWS VIP scale, and the Miami controller had both extent and intensity information available to him.