NTSB Identification: MIA04FA076
14 CFR Part 91: General Aviation
Accident occurred Tuesday, April 20, 2004 in Tampa, FL
Aircraft: Cessna 177RG, registration: N1910Q
Injuries: 2 Fatal.
This is preliminary information, subject to change, and may contain errors. Any errors in this report will be corrected when the final report has been completed.
On April 20, 2004, about 1134 eastern daylight time, a Cessna 177RG, N1910Q, registered to and operated by a private individual, as a Title 14 CFR Part 91 personal flight, ditched into Tampa Bay, Tampa, Florida. Visual meteorological conditions prevailed and no flight plan was filed. The private-rated pilot and one passenger received fatal injuries, and the airplane incurred substantial damage. The flight originated in Pompano Beach, Florida, the same day, about 0930.
Witnesses offloading cargo from ships at the Port of Tampa Bay, stated that they heard the accident airplane make a "popping" noise, and they looked and saw the airplane in a controlled descending turn. One other witness stated that he was about one mile away in a small boat installing a "fish finder", and he became aware of the airplane when he heard a loud smacking noise as the airplane hit the water. He said he then started his 5-horsepower motor and proceeded to the place where he saw the airplane. He estimates that it took him about 3-to 5 minutes to arrive at the location, and that the airplane sank after being afloat for slightly over a minute.
An attendant at the Peter O. Knight Airport, Tampa, Florida, stated that she heard a radio communications transmission during which the voice stated that his airplane engine was experiencing roughness and backfiring. Shortly after the initial call, the attendant said she heard the pilot say "we're not going to make it." The accident airplane subsequently ditched in Tampa Bay, about a third of a mile short of the airport, in about 16 feet of water. Postaccident examination of the airplane revealed no anomalies with the airframe and flight controls or engine. During a detailed examination of the Teledyne Continental Motors dual-drive magneto, the magneto's cam was shown to have lost all lubrication, and the points were seized. Airplane records showed that the last known magneto overhaul was conducted by Electrosystems, Inc in October 1997. The records also showed that the magneto had been reinstalled on July 21, 2003, when the engine was overhauled, but a magneto overhaul had not been performed. Teledyne Continental Motors SB643B Service Bulletin pertinent to subject magneto, specifies that the magneto be overhauled when the engine is overhauled. In addition, Textron Lycoming's Mandatory Service Bulletin specifies mandatory parts replacement at overhaul and during repair and normal maintenance. Examination of the Bendix Fuel Flow Divider which was installed on the accident airplane revealed that the subject fuel flow divider did not have the latest diaphragm installation, as specified in Bendix Fuel Systems Service Bulletin RS-86, dated December 23, 1983.
The National Transportation Safety Board determines the probable cause(s) of this accident as follows:
Improper maintenance by other maintenance personnel, and the reinstallation of an unserviced magneto during an engine overhaul, which resulted in the magneto malfunctioning, a loss of engine power, and the airplane being ditched into the water.
The most current "Factual Report" that has been released can be found at http://www.ntsb.gov/ntsb/brief2.asp?ev_id=20040426X00509&ntsbno=MIA04FA076&akey=1