terrylewis
First Officer
Flight distance : 3517287 ft
United States
Offline
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Flying always requires a balance of risk assessment versus reward. Trying to squeeze every last bit of fuel from our batteries requires conservative piloting strategies that take into account the possible reduced propulsion output and slower response at these low fuel levels. Situationally, unless pilots actually practice flying under these "low fuel" situations and understand the flight envelope, they should not continue flying below 30% other than returning home and landing.
For a short period of time, DJI aircraft were dropping from the sky due to inteligent battery cell shutdowns. DJI incorpoated improvements so that propulsion output is automatically adjusted based on battery temperature and cell voltage. Horizontal and vertical speed are also decreased to avoid triggering battery protection.
You originally posted the video of this flight which showed your aircraft climbing above a skier who tracked from the bottom of the frame to the top of the frame with the Inspire looking straight down. As the skier exited the frame top, it appears that the pilot began decending to pan up and behind the skier. It appeared that the Inspire settled into the snow behind the skier and then power was applied to climb out of the snow and return to the pilot's location for immediate landing.
Based on your RC logs, the pilot stick inputs correspond to the previously posted video recording:
The six cells of the Inspire battery appear to have operated as stated above. Realizing that between 3.4 and 3.3 volts, the battery is essentially on "low fuel light", the power reduction kept you flying without battery shutdown:
Battery Cells
If you review the healthy drome summaries, it appears you were operating in an area that may have contained quartz deposits or some other interference was reducing your RC-> aircraft communication and reducing your GPS signal:
From your RC log, it appears that the decent/throttle stick input was excessively long, perhaps due to poor control communications, and the aircraft settled into the snow. The batteries operated surprisingly well to keep the aircraft powered even after settling into the snow.
This conjecture can ony be confirmed by reviewing the aircraft Flight Data Recording logs and comparing the information the aircraft was actually receiving.
If you want to share the aircraft log for this flight, I'd be glad to take a look and compare the flight from the Inspire' viewpoint.
It really sucks that the camera was damaged, sorry!
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