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I use small 2S and 3S lipos to fly small FPV cine drones with ELRS receivers, for example drones by Betafpv, Geprc and Flywoo. 

I am investigating a control problem which is un-commanded control movements causing drones to crash.
Typically these lipos, eg my Gaoneng 3S lipos previously had 650 mah capacity and were rated 120C/240C. Now my new Gaoneng 3S lipos have 880 mah capacity and are rated 160C/320C.

I believe the un-commanded control movements only occur with the higher current 160C/320C lipos. I asked Gemini has this problem been reported?

A. The issue you are describing is a known phenomenon in the FPV community, often referred to as "high-C noise" or "voltage transient interference." While Gaoneng (GNB) batteries are generally well-regarded, the jump from a 120C to a 160C/320C rating (even if the numbers are slightly inflated for marketing) implies a significant decrease in Internal Resistance (IR).

This lower resistance allows the battery to deliver current much faster, which inadvertently triggers two specific problems in small cine drones.

1. Electrical Noise (Voltage Spikes)
High C-rated batteries can produce extreme current "punches." When your ESCs rapidly change motor speed to stabilize the drone, they draw huge bursts of current. Because the 160C cells have very low IR, these bursts create massive voltage spikes.

The Result: On small 2S/3S builds (BetaFPV, Flywoo, GEPRC), the onboard capacitors and filtering are often "just enough" for standard batteries. The sharper spikes from the 160C batteries can bypass the FC's filtering and reach the Gyro sensor.

The Symptom: The Gyro sees this electrical noise as physical movement. It tells the FC to "correct" a movement that didn't happen, leading to a sudden twitch, a "death roll," or a full crash.

2. PID Tuning & Motor Authority
In Betaflight, the "strength" of your controls is proportional to your battery voltage.

Voltage Sag: Your older 120C batteries likely "sagged" (dropped voltage) significantly under load, which naturally dampened the drone's reactions.

Higher Authority: The 160C/320C batteries hold their voltage much higher during maneuvers. This makes the drone "hotter." If your PID tune was already close to the edge of instability, the extra power from the new batteries can push the P-term or D-term into high-frequency oscillations (twitches) that the FC can't handle.

3. ELRS Link Interference (EMI)
Small drones often have the ELRS receiver or its antenna mounted very close to the battery leads.

The high-current bursts from a 160C battery generate a stronger Electromagnetic Field (EMI).

This can cause a momentary "Receiver Reboot" or a "packet loss" event. If your ELRS failsafe isn't set to "Drop," or if the RX glitches and sends a rogue signal during a reboot, the drone will jump or move un-commanded before it recovers (or crashes).

Recommended Troubleshooting Steps
To confirm and fix this, I recommend the following steps in order:

Step Action Why?
1. Add a Capacitor Solder a 35V 470uF Low ESR capacitor to the battery pads (if there isn't one already). This is the #1 fix for "High C" twitches. It absorbs the voltage spikes before they hit the FC.
2. Lower PID Master In Betaflight, go to the PID Tuning tab and lower the Master Multiplier slider by 10-15%. This reduces the "aggressiveness" of the tune to account for the extra power of the new batteries.
3. Vbat Sag Comp Enable "Vbat Sag Compensation" in the Betaflight PID tab (set to 100%). This tells the FC to automatically adjust its "strength" based on the battery's performance, helping bridge the gap between your 650mAh and 880mAh packs.
4. Check Antenna Ensure your ELRS antenna is at least 15-20mm away from the main power leads and ESC. This reduces the chance of EMI from high-current bursts interfering with your control link.

Has this happened on multiple drones, or is it consistently one specific model? If you tell me which model is crashing most often, I can give you the specific capacitor size or Betaflight CLI commands to try first.
END

This has got me interested, I am thinking how I will handle it.

The Jetson One electric aircraft - a quadcopter - costs US$128 000 and in California does not require a pilot licence.

https://www.youtube.com/shorts/2qbQHWsm7Do

Here is a race for Jetson One pilots
https://www.youtube.com/shorts/6BrYX1g4UO0

It does face many competitors and many similar personal electric quads have appeared at Chinese aviation shows.

Gemini says:
The Jetson One is a single-seat electric vertical take-off and landing (eVTOL) aircraft designed for personal recreational use.1 Because it is classified as an "ultralight" vehicle in the United States (FAA Part 103), it does not require a pilot's license to operate.2

1. Performance & Flight Capabilities

• Flight Time: Approximately 20 minutes (dependent on pilot weight and weather).3
  
  
• Top Speed: Software limited to 102 km/h (63 mph).4
  
  
• Service Ceiling: 1,500 ft (457 m) above ground level (AGL).5
  
  
• Flight Control: 3-axis joystick with a throttle lever (left hand controls altitude, right hand controls direction).6 It features hands-free hover and emergency hold functions.7
  
  

• Dimensions (Unfolded): 2,480 mm (L) x 1,500 mm (W) x 1,030 mm (H) (approx. 8.1 x 4.9 x 3.4 ft).
  
• Dimensions (Folded): Width reduces to 900 mm (approx.8 3 ft), allowing it to fit in a trailer or large van.
  
  
• Empty Weight: ~86 kg (190 lbs).9
  
  
• Max Pilot Weight: 95 kg (210 lbs).10
  
  
  

• Motors: 8 electric brushless outrunner motors (coaxial configuration).11
  
  
• Power Output: 88 kW (approx.12 118 horsepower).
  
  
• Battery: High-discharge Lithium-Ion battery.13
  
  
• Charging Time:
  
  • 1 hour at 230V.
    
  • 2 hours at 110V.
    
  • Note: Batteries are swappable to allow for back-to-back flights without waiting for a charge.14
    
    

• Propulsion Redundancy: The aircraft can sustain continuous flight even if one motor fails.16
  
  
• Ballistic Parachute: Equipped with a rapid-deployment parachute for critical emergencies.17
  
  
• Obstacle Avoidance: LiDAR sensors help track terrain and avoid obstacles.18
  
  
• Chassis: All-aluminum space airframe with a safety cell and crumple zones.19
  
  
• Auto-Land: If the pilot releases the controls, the craft automatically hovers; it can also perform an emergency auto-landing.20
  
  
  

• Price: Approximately $128,000 USD.21 (Prices have risen from the initial $92,000 launch price).
  
• Deposit: A down payment (approx. $22,000) is typically required to secure a build slot.
  
• Availability: Production is highly limited.22 The 2024 and 2025 production runs were reported as sold out, with new orders likely being scheduled for 2026 delivery.23
  
• Delivery Status: The first customer delivery (to tech entrepreneur Palmer Luckey) was completed in September 2025.24
  
  

• USA: Operated under FAA Part 103 (Ultralight).25 No pilot's license is required, but flight is restricted to uncontrolled airspace and non-congested areas during daylight hours.26
  
  
• Other Countries: Regulations vary significantly; prospective owners must check local aviation authority rules regarding eVTOL/ultralight operation.
  

https://www.youtube.com/watch?v=8Qqq5MJ1XYc

Remarkable video on how FPV started in 1986, in RC planes, and its subsequent evolution. A security camera was attached to a RC plane and they figured a way to wirelessly send the video feed back to the pilot. Drones and multicopters did not emerge till many years later. This history makes the claim that DJI has hacked FPV.

NickFPV is from Sydney and is starting an operation to manufacture and sell drones, with a 4 inch called the Archetype and a tiny whoop in the pipeline - they will be sold at MantisFPV and an outfit called Aether FPV.

You can place a backorder for the Archetype 4 inch drone with O4 PRO at Aether FPV for shipping in January.  https://aetherfpv.com/collections/drones...bind-n-fly
MantisFPV has the Archetype frame in stock:
https://www.mantisfpv.com.au/aetherfpv-a...-kit-t700/

Nick has done many good drone videos on youtube, including discussion of his relation with MantisFPV and with Newbeedrone. I once briefly met him when flying my drone at a bushland site. Nick is exploring how a drone freestyle competition might be established and how it may be judged.

There is an interesting video on charging tx lipos by Joshua Bardwell

https://www.youtube.com/watch?v=BDJZya1VGY4

He points out that newer Radiomaster txs coming AFTER the Tx16 and the Boxer - that is the TX15 Max and GX12 - have a "Smart Balance Battery Circuit". This means when you plug your tx into a charger, the lithium battery inside gets a balance charge. For earlier txs including the boxer and Tx16, the 2S lipo (or lithium ion) batteries receive a non-balanced charge when charged inside the tx, and Bardwell explains why that might be problematic. If the 2 cells have a different internal resistance, a voltage imbalance may develop over time and might be unnoticed as one low cell and one high cell may add up to a normal total voltage, and a potentially dangerous imbalance may develop.

Its easy to check. In my boxer I have a Radiomaster (RM) Lipo 6.2 Ah lipo pack plugged in by the balance lead, and my Tx16 has a RM 2S Li-ION 5.0 Ah pack, also connected by the balance lead. Both these batteries have a charge lead with an XT30 connector, so when they are removed from the tx it is simple to plug them in for a normal balance charge on a regular balance charger. 

After about 3 years of use with countless charges without ever removing the batteries from the 2 txs I found:

On the Boxer lipo the 2 cells had 3.987 v and 3.956v, difference 0.031v. When charging them to 4.2 v the IR was 48 and 51.
On the TX16 Li-ion the 2 cells had 3.908v and 3.877v, difference also 0.031v. When charging them the IR was 36 and 32.

I don't think any problem was imminent with these 2 txs, but I plan to do a lipo check maybe every 6 months. Keeping lithium packs balanced likely extends their life.

I recently posted a thread "The best FPV drone for flying indoors" and the Neo easily beat the other 7 small drones, of which 5 were 2S and 2 were 1S.
 
 After more experience in outdoor locations, I conclude the Neo easily beats the same competition outdoors.
 
The video system and camera on the Neo looks at first glance like the DJI O4 lite video system on the other 7 drones, but it is not. When you connect the Neo to the DJI goggles 3 you have to select Neo, it will not accept DJI O4 which is the required selection for the other 7 drones. The Neo has a much wider field of view, and field of view is the only weak point of the other 7 drones. With the NewBeeAcrobee75 HD O4 2S drone I was able to fit a wide angle lens, but I am not able to fit such a lens to the other 6 drones. The wider field of view helps when flying in a forest.
 
When I fly the Neo in a forest setting it has a much better capability than the other drones.

The Neo flight time is 15 min compared to around 5 minutes for the others.

The ability of the Neo to hover in place is astounding, though I suppose this is expected because it is the only small drone with GPS. The other small drones can be a bit tricky with a 5 kt breeze (especially the 1S drones)  but the Neo handles this readily. The stability of the Neo makes it easy to fly through small gaps that may be difficult with the other drones.

I have done a video of the Neo in a forest but I cannot post it even though the video has been reduced in size to 18.8 MB - does this Forum accept MP4 and MOV video files? I have tried both. The error message says ask the administrator, can anyone advise....

In a previous video I commented on an issue with landing the Neo when flying FPV, and there was a recommendation by Gemini to use the palm landing. I find this is a perfect solution, and ensures the drone does not get wet when forest conditions are wet, and avoids dust or twigs or debris getting into the drone. Gemini says you have to flip the drone to cut the motor after you land it on your palm, but this is not required in my experience. Here is my landing method:
- Fly the drone towards me and have it hover at 1.5m above ground, when it is 1 or 2 m from me.
- turn the camera gimbal 90 deg downwards using the fpv controller switch
- remove goggles and place the fpv controller in a convenient place
-place my hand with extended fingers about 10 cm directly below the drone. It immediately descends slowly and lands on my palm, and automatically cuts the motors after touch down.

Finally the Neo has the best prop guards out of all the small drones, and I have not yet had to replace a propellor.

I sought AI help with Gemini on a landing issue:

Q. When landing the DJI Neo flown with the DJI FPV controller and goggles 3, I have a problem. I cannot use the RTH (return to home) method, as I am flying in an area with multiple tall trees and overhead branches, and overhead wires, and RTH always involves a minimum initial climb of at least 20 m. If I simply lower the throttle, when close to the ground the Neo skitters sideways away from the landing pad.

A. This is a common issue with DJI's standard flight modes (Normal or Sport) and their vision positioning systems, which are designed for flight safety. The "skittering" is likely due to the drone attempting to stabilize itself based on its downward sensors and attitude control, which can become erratic very close to the ground, especially on uneven surfaces or with slight wind.

Here are the key points and potential solutions based on your equipment and situation:

RTH Minimum Altitude: The default behavior of RTH is to ascend to a preset altitude to clear obstacles. As you've noted, this is a problem in your environment. You are correct in avoiding RTH.

Auto-Landing near Ground: In Normal or Sport mode, the drone is programmed to auto-land if it detects a low altitude (e.g., around 0.5 to 1 meter) and you hold the throttle down for a few seconds. This is often the cause of the sudden, undesired movement as the drone takes over to land. It's an intentional feature to help with controlled landings but is not ideal for precision manual maneuvers near the ground.

The Solution: Manual Mode (Acro Mode):

Since you have the DJI FPV Controller 3 and Goggles 3, you have access to Manual Mode (often called Acro Mode in FPV). Manual Mode disables the self-leveling and vision positioning system's influence on flight control. This gives you complete, direct control over the throttle, pitch, roll, and yaw, meaning the drone will no longer try to auto-land or correct for ground effect or sensor readings near the ground.

Caution: Manual Mode requires significantly more pilot skill, as the drone will not automatically level itself or hover. If you stop providing stick input, it will drift and fall. It is highly recommended to practice extensively in a flight simulator (like Liftoff) before attempting a Manual Mode landing in a real-world, confined space.

Manual Landing Procedure (in Manual Mode):

Switch the drone to Manual Mode (if you have enabled it in the settings, which is required).
Fly to a point directly over your landing pad.
Slowly and deliberately lower the throttle stick until the drone descends. You must maintain precise control over the pitch, roll, and yaw to keep it level and stationary over the pad.
Once the drone makes contact with the ground, immediately push the throttle stick down and hold it for a few seconds until the motors stop (or use the motor stop command specific to your controller's setup, which for the FPV Controller 3 in Manual Mode may be the double-tap of the Start/Stop button).

Hi All - a local contacted me on the weekend as he had found a powered glider in his backyard! Photo and contact details below. Please pass this on to everyone who flew over the weekend.

   

Contact details are: 0400 232 800  - Piquet Place in Toongabbie.

On another note, could someone in the club please add their contact details to the Google entry for the Club. Somehow Google has added my mobile number, and peple keep calling me, but I have not been a member for over 5 years!

Regards Simon de Lisle

What is the best FPV drone for flying indoors, especially if you live in a normal house or apartment that lacks high ceilings? I have tested 8 drones with the DJI O4 lite video system that are suited to indoor flying, although I have also flown them in the backyard, the street, over rivers and canals, bush tracks and reserves, and local parks including tiny parks. Of the 8 drones, 2 are 1S drones and 6 are 2S, and the 1S drones are notably smaller and lighter. All these drones give excellent and stunning video performance with either the DJI goggles 3 or the goggles N3.

To fly a fpv drone with the DJI O4 lite video system you need either the DJI goggles 3 AUD 869 or the DJI goggles N3 AUD 359. Both give excellent results.

DJI Neo  drone AUD 299.  To fly this as a FPV drone you need the DJI FPV controller 3 AUD229

The other drones are flown with any elrs transmitter/controller.

NEWBEEDRONE ACROBEE75 HD O4 2S  AUD404
 
HAPPYMODEL MOBULA7  O4 2S racing drone  AUD499

BETAFLIGHT FEMTO 2" 2S  AUD 390

SUB250 NANOFLY20 2S 2 Inch HD O4  AUD549 

FLYLENS 75 O4 2S Whoop FPV Drone AUD 414

FIREFLY18 1S Nano Baby V3 O4 with Flywoo DJI O4 Lite Wide-Angle Lens 360AUD

METEOR75 PRO 1S O4  416AUD 

Indoor fpv is difficult and harder than I expected. Beginners should definitely learn to fly outdoors first. When flying indoors sensible people (I include myself, and top fpv gurus such as Bardwell and Captain Drone) fly in angle mode, although real men claim to fly in acro mode.

The WINNER: The DJI Neo is the winner by a large margin. It makes flying indoors easy, because it has rock steady stability. With the other 7 drones, if you loose full concentration for a split second you may bang into a ceiling or a wall; this helps explain why all but 2 of the above drones have prop guards. With the Neo you have an option to convert the  DJI FPV controller 3 into full manual mode, which makes it fly like any other fpv drone. However I use the controller in the default mode it is sold with, ie angle mode + stabilisation. With the Neo in angle+stabilisation if you release the sticks it hovers in place at constant altitude, which is not the case with the other drones.

For elrs and edgetx users, here are instructions for placing a lua script (downloaded from github) on the sd card of your tx. When an aircraft is lost, you run the script as explained in the video, and your tx then guides you to the right spot. The full explanation and demonstration are here. I already use a similar approach by having my tx call out the RSSI value every second or two, using a special function, and this allows you to move closer to get a lower/stronger RSSI value until you see the downed plane. But the lua script seems to be an advance, I plan to try it. 

https://www.youtube.com/watch?v=eeNZkG-rxLY