atomRC Dolphin over 200MPH! 320km/h!

airframe : AtomRC Dolphin 845mm
Motor : BrotherHobby Special Edition V4 2816 1050Kv
ESC : Flycolor X-CROSS HV3 80A
Prop : Schulze luftschrauben Super-S speed line 6.5x6.5
Servo : Blue Bird BMS-125WV
FC : matek F405-WMN + INAV 7.1.1
Battery : 2 of Tattu R-Line 6S 1400mAh
TVS diode : SMCJ51CA, SMCJ54CA for 12S battery, SMCJ24A, SMCJ26A for 6S
Low ESR high ripple capacitors are added
I'll test brotherhobby's 32.5-12/1050Kv
I want to get more RPM.

[@WipeoutFPV]

Decent setup - looks genuine too, no GPS surges. Just needs a level flight two way run!

[@smackfpv]

Hey! Now this is better for sure. I can trust the numbers this time as opposed to the last video I commented on. Only thing that is missing is a speed run the other direction to account for a tail wind and then average the numbers for top speed. It was very windy when you launched and that could be good for 30 to 40 kph.Well done though!

[@celeselements]

Thank you! I'll try again when there's no wind!
Watch my video about Alpha Strike!

[@andreyl2705]

awesome)

[@celeselements]

Thanks 😁

[@SFPFPV]

Ecalc is usually very accurate and shows the motor pulling over 3000 watts and only going 173MPH. I wonder why it's so off.

[@celeselements]

Yes, the data of Ecalc is really vast and precise. I think that driving a 14 pole 1050Kv motor with 12S is probably foolish in terms of efficiency, so it is not in the data.

[@DODICZEK]

That fast!

[@celeselements]

Thank you!

[@robertoricardo182]

Soon will mod atomrc delta strike (edf) to pusher and use similar kv seput but with 6S and lighter plane. 6S 2800mah and 2814 2200kv motor with graupner speed cam prop 5.2x5.2. Let's see, my goal is 300kmh 😅

[@celeselements]

Good Luck!
I think it would be good to change the three wire of the motor to a thicker one.

[@robertoricardo182]

​@@celeselements since I use EDF tunnel to air flow and space the phase wires only have 3cm motor to esc!

[@celeselements]

@@robertoricardo182 COOL!

[@fpvwing]

Very good. How many amps maximum? I use 3115 1500kv motor but only 6S, with 7x4, might try 7x10

[@celeselements]

Thank you!
At my configuration, the FC can't measure the current on ESC. I didn't check the current with other instrument, but the ESC temp is rise over 194°F(90°C). My ESC is 80A spec, I think the current exceeds that spec. The RPM mark 33,000RPM at full throttle.
Your setup looks robust and fast!

[@pk2396]

3115 1520kv 6s 7x6” 250km/h horizontal 22*C
Pulling roughly 1kW @ 200km/h
1.9kW @ 250km/h
I think with better batteries it would be a little faster.

[@celeselements]

Great work!
I choose 12S for small difference and future options.
I think 12S has a pros at full throttle sustaining than 6S.

[@paparambo2557]

i have a question i build my own dolphin and i got the at75a tmotor esc. i just checked of everything works and my motor does not spin. i can hear my esc beeping but i cant spin my motor.. what could i do?

[@celeselements]

It may not be a problem with the motor or ESC. The beeper sound comes from the motor, which means the ESC and motor are well connected. You might want to check the top and bottom of the throttle and the reverse. If you have FC, please check the receiver's behavior on the Receiver tab.

[@unknowninvictus2520]

why did you add a giant cap on the FC board (the one just before the cooling fan of the ESC)?
Also, Very nice and fast dolphin build!

[@linhtet9279]

Cuz sudden voltage spike

[@unknowninvictus2520]

​@@linhtet9279 Yeah but that doesn't look like the battery circuit?
and what uF does he use.

[@Brian-S]

​​@@unknowninvictus2520you can add a small cap around 220uf to the vbat and ground pads on the flight controller. It helps to clean up the noise before power goes to the regulator on board which goes to the gyro. The less noise you can get to the gyro the better. Never really seen it in wings but it's pretty common on larger or power hungry quads

[@celeselements]

Thank you! You're sharp! A cap on FC is for rush current, surge, etc. honestly, it is a overkill. I think the capacitance is OK with 330~1000uF, mine is 680uF 35V.

[@chrisbee5481]

Which motors did you like better? 32.5-12 or 2816?
I believe you tested both, but on different props.
If I can recommend you a fast prop from my test: APC 6.5x6.5
I dont know why, but smaller props have been faster top speed and more efficient.

[@celeselements]

32.5-12 is on the way to my home.
I think 32.5-12 is a bit bigger and heavier motor, so it can handle more larger prop.
I'll test your recommended prop and APC 5.25x8, 7x11, high pitch prop.
7x11 will burn 2816/1050Kv motor.
Small props has smaller disk area, it act as drag.
I'm looking for a way the best result for me among RPM, speed, current draw and sound!

[@chrisbee5481]

@@celeselements I tried the APC 7x11 prop with 3110 motors. They didnt get fast at all and just draw high current. The problem is they have so much pitch, that they stall at any speed below 200 kph. So even getting in the air is not optimal.
I wouldnt try more than a pitch of 8.
Also not go bigger than 6.5 inch or stay below 7 inch.
With a 5 inch prop you will need higher kv motors.
If you want more silent, three blade props and a pitch of 5 to 6.
But top speed and higher speed cruise efficiency is not as good.
Just ordered some 32.5 12 950kv for 8S with 8x6 props

[@celeselements]

Thanks for sharing.
I have similar experience about 7 inch prop(Super-S 7x7).
As you can see in the video, RPM reach 40K. I think the motor is close to the mechanical limit.

[@ngocoan576]

12s lipo 🤯🤯🤯🤯?

[@celeselements]

Yes! It driven by 12 cell battery!