Hi guys, I'm fairly new to the world of rc flying and have recently purchased a P4 and having lots of fun with it. I took the P4 out in very windy weather yesterday and managed to get 32 m/s out of it (115kmh or 71.5mph).I flew 2.8km along a very remote coastal area down wind when I realised that I couldn't make it back because of the head wind! I was forced to set it down 3kms away behind a deserted beach in knee deep grass. Now I had a 1hr hike along the cliff tops ahead of me to retrieve it, I did manage to find it and it suffered no damage. Lesson learnt! I now know to only fly up wind in these conditions.
Phantom 4 Top Speed (Wind Assisted)
- Thread starter Stoney
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Definitely was a nail biter but ended up ok in the end. I've got sore feet today from the hike though!
Nice, I was somehow able to get mine to a top speed of 84 mph the other day. It was flying!
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If I'm not mistaken, and a might be, something about the curvature of the earth, there is a negligible difference (and it's counterintuitive) that you actually travel less distance to get from A to B at a lower altitude from what I just read because I thought it was the other way around.
The differential factor is negligible at by like .21 factor or something. But it says, that you get more efficiency at higher altitudes because the air is thinner. Not sure how true that is at 75 meters vs 300 but maybe read up on it. I think the move when you are running out of battery and are worried about making it back is to get a little higher until your battery is getting low and then get lower for obvious reasons. I am not 100% on this and I would read up more on it. I will be.
The GO logs numbers are not accurate. In-flight speeds and altitudes are greater than shown in my GO app as I am flying. My top speed in the logs show 89 mph. I never went that fast, in the low 70's sure, my max elevation is also off by over 300 feet. One thing for sure is that with the wind helping you along you get home PDQ. One very windy day going in the wind turned around at 53% and got back home at 37%, (all in s mode) going out I was getting something like 16mph, coming back was in the 70's. (That was fun)
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I could stand to be correctly, but I believe the Top Altitude data stored within the Go App is you actual top take off altitude, not your top flight altitude. It used to be named Take Off Altitude in earlier versions of the Go App I believe and I didn't pay attention to what it was recording and thought my altitude was way off as well until I realized it was take off height, not flight altitude.
That would make more sense, it would be off by maybe 30 some feet. Next time I travel where the elevation would have a considerable difference from here I will backup my logs and start fresh and see how close it's to the actual take off elevation.
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Any advantage you might get at a higher altitude (and I doubt it would be significant if at all) is likely to be less than the loss of battery you'd experience by climbing with a weak battery.
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Maybe, as I said, I am unaware of the actual number and "I doubt it would be significant at all" but I would look at it.
It's all about numbers.
For example, as any pilot on here will tell you, for a scientific reason I couldn't really tell you, when at very high altitude (like 35k) for some reason the curveture of the Earth actually makes the trip shorter because of where you fly and while seeing if that makes a difference at such a low altitude (it doesn't), I ran into debates as to whether or not it's better to go higher to get to thin air or not.
Most people say it depends on how much battery is left and how much distance. Don't claim to know so just saying I would read up on it as I will in case I ever find myself in a similar situation.
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That sounds like confusion with great circle flight routes which are shorter than the straight line on the map because of curvature of the earth.
And the increased efficiency jets encounter flying high in thin air (less friction).
Neither is much help flying a Phantom.
But if you are concerned about getting home when your battery is low, don't waste any volts climbing to a higher altitude.
You need the juice for getting home.
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Yes, I was considering both of those things that you are showing. I didn't exactly know how to explain the curveture as well as your image does but I was saying I don't think that matters but thin air, I don't know either, and it also depends on how high you already are and how far you actually are. I haven't done any studies on what the move would be so don't claim to know.That sounds like confusion with great circle flight routes which are shorter than the straight line on the map because of curvature of the earth.
And the increased efficiency jets encounter flying high in thin air (less friction).
Neither is much help flying a Phantom.
But if you are concerned about getting home when your battery is low, don't waste any volts climbing to a higher altitude.
You need the juice for getting home.
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