Why 5"?

So I’m very happy with my Diatone 349 3" quad… But my browsing has led me to this…

And I’m wondering… What really is the benefit of larger quads? Do they fly differently? Do full size TX components give better range…?

Longer arms = longer props = lager motors = 6 cells = ballistic.
There’re YouTube videos to answer the TX question, worth a watch…:+1:

Ok so it’s speed eh? Tbh, not finding the 3“sluggish. It’s been clocked at over 100 by some you tuber. But I’m more in it for freestyle tricks (which I’m sorely lacing the skills for currently!) and I was wondering if the extra weight of a larger quad would help with some of the moves when you’re using the quads own mass to carry through with throttle down?

Also, is it OK to pick up something pre-assembled like this diatone? Or should every self respecting pilot actually build their own!

Hey tom.

Extra mass does help when trying to do some moves(to a point)…

As to build vrs buy…

Time rich build…time poor buy imho

Doesn’t really matter as you will get the soldering iron out anyway lmao

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Hi @tom.at.rye

I have a number of acro/fpv machines in different sizes, the biggest being my Vortex 285’s. Even though they’re capable race/freestyle quads, for their age, due to their bigger size I can easily fit a ubiquitous 3s2200mAh pack. This allows for close to 10mins of cruising and exploring and getting some smooth floaty type video.

WRT range. I fly mainly with FrSky (Taranis X9D) and to-date I’ve not experienced anything close to a failsafe or brownout. All the receivers I use are considered “full range”, from the tiny XSR to the bigger X8R. I do have some models with Spektrum DSM2/DSMX receivers but I only trust these for close in proximity use.

As for the build or RTF route? I personally think it’s dealers choice and theirs alone. If someone has the time and resources to build then good for them, but I don’t recognise them as being any better than someone who goes the RTF/PNF route. In fact I’ve come across some “build it” procrastinators who’d have been better off going the RTF/PNF route.



Why 5 inch? It comfortably fits a gopro or similar on it.

Now that sounds a good reason if any! I hadn’t realised that the flight time could go up so dramatically. I had always thought mAh to weight would cancel each other out.

And yeah. . @notveryprettyboy whacking a go pro on top seems liek a good idea, specially when it comes with good image stabilisation like the hero 7, but CURRENTLY I don’t think anyone particularly wants to see my footage. . I barely bother to put an SD card in! Ill wait till I get better. . . . .

Thanks all for the tips!

There must be an interesting correlation curve … somewhere … but don’t forget the MP/M2P manage 25/30 mins … at far more overall weight, and more battery weight.

There must be efficiencies in prop performance with size, I’d imagine.

(My (very) little Cheerson CX10 only manages a couple of minutes.)

Yeah but I get the feeling that Mavics operate at much lower voltages don’t you think? You just can’t make 'em scream like a quad!!

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I was comparing to the “10mins of cruising” quoted above. I’ve had my MP sat at about 30mph for a full 20 mins.

Most of the work done by the motors is combating gravity (and then air resistance at extreme speeds - but lets stick to “cruising”) so, (assuming identical prop/efficiencies) for the same work its watts that are proportional to the weight … and watts = volts x amps, so lower voltage = higher current to achieve the same power. Without needing to know what voltages are used, voltage makes no difference.

I know. That is really spectacular performance whichever way you look at it. From a quad you’re lucky to get 5 mins.

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Yeah - and it seems that around that 25/30 mins is the limit that’s available (whilst remaining practical) …. so many of the better makes/models sit in that window.

And there’s one thing we know for certain …. if they could make it longer, they most certainly would!

If someone came up with a 60 minute flight time for something that was basically the same as the MP … this forum would be awash with saliva! :wink:

I think if you mounted a miniaturised nuclear reactor on the top of it, that should do the trick? But then there’d be all the moaners. . . “oy you’ve crashed your nuclear drone in my garden. . .now I’m going to have to decontaminate. . blah blah blah. . .” Anyone tried solar panels?

Hmmmm …… but they won’t be light, and I wonder how big they would have to be to produce the power to lift their own weight.
Another interesting set of cures …. nuclear reactor power-plant weight v power output v lifting power v overall weight of “drone”.

Hydrogen cell might be more practical … in many ways. :wink:

You just want the 5-hour flight time of one of these, don’t you?

Yeah - small gas turbine generator.

Hydrogen cell should give better power to weight ratio.

Mavic’s also use FOC (Vector) control making the motors very efficient by lowering flux current.

Similar to industrial variable speed drives.

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Yeah, I was about to say it must’ve have something to do with vector flux control current variability in the FOC Driver. . . d’oh! Why didn’t I realise that straight way?


So does that mean they have a flux capacitor. And if a mavic 2 hits 88mph it will disappear in a a flash of light. :rofl::rofl::rofl::rofl:

Amazingly, you’re spot on with the speed! Some fly away… “dude, I’ve lost my drone in the jurassic era! DJI refresh…?”

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