On January 3, 2004, a Maule M-7-235B (registration N10430) was involved in an aviation accident near Fort Lauderdale, FL. Investigators recorded the probable cause as: The pilot's decision to deploy full flaps while landing on glassy water, which caused the right float to dig in and the aircraft to invert. This summary draws on records from the U.S. National Transportation Safety Board (NTSB) historical archive.
A float-equipped aircraft inverted after landing on a calm lake when the right float dug in during touchdown with full flaps deployed, according to pilot statements.
What happened
The pilot reported that the conditions on the lake were exceptionally smooth, describing the surface as "glassy." In preparation for the landing, the pilot elected to lower the aircraft's flaps to the full extension setting. Upon initial contact with the water, the right-hand float submerged deeply into the surface. This sudden resistance caused the airplane to pitch forward violently. As the nose dropped, the right wing struck the water, leading to a loss of control that resulted in the aircraft flipping over and coming to rest upside down.
The investigation
Post-acc examination revealed no evidence of mechanical failures or malfunctions prior to the impact. The pilot confirmed that the aircraft was operating normally before the landing attempt began.
Findings
The primary factor contributing to the accident was the decision to use full flaps on glassy water. This configuration caused the right float to dig into the calm surface, initiating the forward pitch and subsequent inversion.
Probable cause
The pilot's decision to deploy full flaps while landing on glassy water, which caused the right float to dig in and the aircraft to invert.