Fellsteruk wrote:Proper battery management and thermal cooling is the way to battery longevity but I guess only time will tell as to how good they are or how bad the degradation is.
A lot of the training material for the Velis (unsurprisingly) is about battery management. There's an estimated figure for the number of charging cycles a battery can handle, provided you treat them well. I don't have the figure in my head; let me get back on that. The Lithium-Polymer technology is not new, of course, so the estimates are based on real-life experience.
The batteries will need to be replaced at some point. I guess you could see the replacement cost divided by the number of hours flown as a part of the "fuel cost", the other part being the actual electricity. A 40 minute flight will use perhaps 20 kWh, which costs in the region of two to three pounds (with Swedish prices), so there's room in the fuel budget for battery replacements.
Cooling of the batteries is important not only for longevity but for safety: you really, really don't want a battery fire in-flight. One of the main differences between the earlier prototype Alpha Electro and the Velis is the cooling. There's a liquid cooling system and also quite large air intakes on the sides of the aircraft. AIUI, those changes were important for the EASA type approval. It cost some weight, though, so the ballistic parachute that was in the Alpha (and that we have in the Rotax-powered Virus) is gone. I believe they removed the speed brakes for the same reason.
If there's a particular part of the aircraft that anyone is interested to see, make a post here and mention my username so I don't miss it. I can take a picture and upload when I get the chance. (The engine would obviously be interesting, but I can't remove the cowling.)
Autocorrect is so frustrating. It's always making me say things I didn't Nintendo.