My last few flight sessions have been with the new DT-180 drone. Some general LoS flying, but also trying to practice my FPV. Today, I thought I would take my Novas over to the school-field for some flights. Partly cloudy, 90f, and 5mph winds.
Super-Nova (newer Nova #2):
As I get to the field and get everything setup and ready for take-off ... I feel a few sprinkles. I look off in the distance, and a new dark thunder-cloud is approaching. I decide to go for it.
On power-up, I noticed that the Nova's power-up sequence of motor/esc twitch/beeping was different and abnormal. I tried again and got the same. I didn't think much more of it since it Armed ok. I likely bumped the throttle a couple of times to test motor spin, (as I usual do) but not sure. I felt a few more sprinkles so it's now or never. On take-off, it flipped over. Compass puck got cracked. Nova will still Arm, but back/left (aft-port) motor/esc set will not spin prop. Super-Nova definitely not living-up to its name. It never rained.
It took two Nova's and 2 years of flights, but it appears I have finally experienced a stock ESC or Motor failure. Caught me totally off-guard. The Nova was trying to tell me something (a few extended seconds of twitching/beeping of the ultimately non-functioning esc/motor-set on power-up) ... but I didn't understand.
Strange thing about it ... this is the newer Nova (with the v1.6 ESCs), and it 's never been crashed (well, unless you count just now when it flipped on take-off due to a non-spinning motor). Whatever component went bad here, it appears to have happened while Nova was sitting on garage shelf. Either that or it happened on initial take-off/throttle-up/amp-up.
In light of this event, I'm gonna have to add a couple of steps to my main pre-flight checklist.
- Listen for extra (abnormal) beeps/twitching from ESC/Motor sets during initial lipo connection and aircraft power-up (even if it stops after a few seconds).
- After Arming, bump the throttle on/off a few times and make sure all props/motors spin on command.
Because apparently, you can have a failure in a ESC/Motor set and it will still pass pre-arm tests and allow Arming ( basically goes un-detected). Without the pilot performing the above pre-flight observations ... there is no way to prevent a flip/crash/damage when you punch the throttle to take-off.
Current known issues:
1. Repair or replace bad motor and/or ESC in bad set
2. Repair cracked puck and do epoxy mod to reinforce.
3. Check GPS-module cable. I lost GPS for 5 mins during field testing (and it didn't appear to be an GPS-Almanac update).
Only thing here is that both of my Turnigy-2700 Lipos have now puffed-up again and are apparently too large to fit into the old Nova any more (even with PDB raised-up 2mm). I used the Vant-3000 (that I usually run in the Super-Nova) instead.
The Nova flew great. All modes and Loiter. Quanum Retracts are still working fine. Flew around fast and stable. Fun flying and seems more casual than FPV. Just had the one battery that fit, but got over 12 minutes flight-time on it. GPS working OK for a 6-series. Barometer altitude reporting acceptably today on this quad.