A couple acquaintances of mine, Mark & Skip, were killed Tuesday night when their plane had a total electrical system failure and Mark tried to land his Cessna 206 at a rural airport with a lighted, 3,700 ft. strip where his plane was based. Mistakes were certainly made and we'll never really know why they hit trees hundreds of feet out of line with the runway, suggesting Mark turned final way too late, but the question I want to raise here relates to electrical system redundancy.
With homebuilts, we can build redundancy into our electrical systems. So, help me out here on my understanding of our choices for backup in our electrical systems.
As I recall, the simplest backup is to have an essential bus and a non-essential bus. When the alternator goes kaput, you switch off the non-essential bus and proceed, operating on the battery. How long you can do this depends on remaining battery capacity and how much juice you are using.
Then there is the 8 amp alternator that will keep giving you power to the essential bus indefinitely as long as you don't try to power too much off it.
One of our local builders is installing 2 batteries, but my understanding of the rationale is a little weak. Seems to me the 8 amp alternator is a lighter and perhaps a more effective backup.
Pros & cons of the choices? Any other options?
BTW, leaves and needles on trees are designed by nature to absorb light. They get awfully dark at night. Don't take chances near trees at night.
With homebuilts, we can build redundancy into our electrical systems. So, help me out here on my understanding of our choices for backup in our electrical systems.
As I recall, the simplest backup is to have an essential bus and a non-essential bus. When the alternator goes kaput, you switch off the non-essential bus and proceed, operating on the battery. How long you can do this depends on remaining battery capacity and how much juice you are using.
Then there is the 8 amp alternator that will keep giving you power to the essential bus indefinitely as long as you don't try to power too much off it.
One of our local builders is installing 2 batteries, but my understanding of the rationale is a little weak. Seems to me the 8 amp alternator is a lighter and perhaps a more effective backup.
Pros & cons of the choices? Any other options?
BTW, leaves and needles on trees are designed by nature to absorb light. They get awfully dark at night. Don't take chances near trees at night.
Last edited: