Mysterious loss in speed

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I was reviewing a Litchi waypoint mission flown with my P4 yesterday when I noticed the speed dropped well below the 12.5 mph cruising speed I had set. I created this mission using a P3P last year and it flew the same route at a relatively constant speed. I don't understand what's happening here though. The only thing I can think of is Smart RTH. During the flight I experienced a few "Downlink Lost" messages. Could this be the culprit? (I didn't bother disabling the option in the controller) Because I make heavy use of waypoint missions, this is a serious issue I need to get a handle on. The first drop in speed occurs at 1m 27.7s into the flight.

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Meta4

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The only thing I can think of is Smart RTH. During the flight I experienced a few "Downlink Lost" messages. Could this be the culprit?
Your Downlink Lost messages had dn effect on speed.
They are just advising that the downlink was lost and the mission carries on as it would if the complete control signal was lost.
Smart RTH was not involved.
The drone never entered RTH mode during the flight.
 

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I was reviewing a Litchi waypoint mission flown with my P4 yesterday when I noticed the speed dropped well below the 12.5 mph cruising speed I had set. I created this mission using a P3P last year and it flew the same route at a relatively constant speed. I don't understand what's happening here though. The only thing I can think of is Smart RTH. During the flight I experienced a few "Downlink Lost" messages. Could this be the culprit? (I didn't bother disabling the option in the controller) Because I make heavy use of waypoint missions, this is a serious issue I need to get a handle on. The first drop in speed occurs at 1m 27.7s into the flight.

DJI Flight Log Viewer - PhantomHelp.com
Wind? There were 5-10 mph winds in that area yesterday. More at altitude. A few clear speed changes occurred roughly when you changed direction to go around corners. For example, when you turned from S Jones Blvd to W Rochelle Ave. Perhaps it was simply wind gusts? Could it be that simple?
 
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Your Downlink Lost messages had dn effect on speed.
They are just advising that the downlink was lost and the mission carries on as it would if the complete control signal was lost.
Smart RTH was not involved.
The drone never entered RTH mode during the flight.
You're right of course, RTH was never triggered. I was just grasping at straws. I had read another thread on Smart RTH quirks and it made me wonder if that could have been the problem here.
 
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Wind? There were 5-10 mph winds in that area yesterday. More at altitude. A few clear speed changes occurred roughly when you changed direction to go around corners. For example, when you turned from S Jones Blvd to W Rochelle Ave. Perhaps it was simply wind gusts? Could it be that simple?
I just checked the Litchi waypoint values and somehow the cruising speed values had changed! I haven't looked at this route since last year. The drone was flying exactly as it should have. It was all my fault. Sigh...
 
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