Wanttaja
Sky Savant
Got curious about a particular issue: As homebuilts age, do they suffer more mechanical failures?
Grabbed my 1998-2021 homebuilt accident database and ran a quick analysis. The plot below is limited to ages which had at least 50 accidents. This corresponded to the 20-year-old point.
The top line is for all mechanical failures (including those involving the engine), while the bottom (red) line is for failures only with the engines themselves. Both include cases where builder or maintainer error led to the mechanical failure.
As one would expect, there's a peak at the start of the aircraft life....but after that, the trend is apparently downward. Hard to tell, since the number of cases can vary widely. Plotting five-year averages seem to confirm the reduction in the percentage of mechanical issues, although there might be a rise in the ~15 year old category. Drops afterwards, and the rise isn't apparent on the engine-issue factor. There is a spike at the ~25 year point, but by then you're down to ~30 accidents involving 25-year-old aircraft.
Ron Wanttaja
Grabbed my 1998-2021 homebuilt accident database and ran a quick analysis. The plot below is limited to ages which had at least 50 accidents. This corresponded to the 20-year-old point.
The top line is for all mechanical failures (including those involving the engine), while the bottom (red) line is for failures only with the engines themselves. Both include cases where builder or maintainer error led to the mechanical failure.
As one would expect, there's a peak at the start of the aircraft life....but after that, the trend is apparently downward. Hard to tell, since the number of cases can vary widely. Plotting five-year averages seem to confirm the reduction in the percentage of mechanical issues, although there might be a rise in the ~15 year old category. Drops afterwards, and the rise isn't apparent on the engine-issue factor. There is a spike at the ~25 year point, but by then you're down to ~30 accidents involving 25-year-old aircraft.
Ron Wanttaja
