Multicopter won't takeoff

i have a drone running px4 v1.12.3.

in position mode when i try to takeoff, using a remote control, in position mode. nothing really happens.
it arms ok, but when i lift the stick, the motors just spin up very slowly.
i am also not able to start offboard mode (command denied error response from mavsdk).

this only happened after takeing off and landing using mavsdk. but only sometimes. after reboot everything is good again.

can somebody help clearing up this issue.

https://logs.px4.io/plot_app?log=7b127357-641f-4873-98ea-6d735175f5be

Just to clarify, when you’re trying to takeoff in position mode do you raise the throttle above 60%?
You have to take into account that zero throttle is in the center with position mode… had me struggling once. :wink:
Offboard mode needs certain very specific prerequisites like setpoint streaming at 2hz and only can be activated once armed (as I understand it).
cheers

Yep, 100% throttle.
And when i do so, it takes about 10 seconds, to reach hover throttle.

This is after I stop offboard, so these requirements should not matter.

By the way, attitude and stabilized mode work without a problem.

I am writing down all the probable causes why it won’t takeoff -

Scenario 01: Drone Takes off but leans to one side, and almost flips over

Does this scenario sound familiar? If yes then chances are your propellers aren’t on the right motor.

Here’s how you can fix this issue:

  1. GENTLY LIFT OFF DRONE: Try to lift off and see which side of your drone stays on the ground.
  2. SWOP PROPELLERS THAT STAY ON GROUND: Swop the two propellers that stay on the ground. For example, if the left side of your drone stays on the ground while trying to take off, swop those two propellers around with each other.
  3. FLY. Your drone should now be able to fly without any problems.

Seems simple? Because it is! This issue has baffled thousands of newbies, and you can literally fix it in a few minutes.

If that didn’t work for you, here is the second biggest issue we see with drones today.

Scenario 02: Drone is on, and connected, but won’t take off from the ground

So your drone’s battery is connected, you’re getting a live stream and the drone is lighting up, you’ve not crashed recently, propellers might even be spinning but it just can’t seem to lift off from the ground.

There are five common mistakes that could be causing this.

01. Your propellers aren’t on tight enough

What usually happens here is because the lock nuts aren’t tight enough, which causes the propellers to slip on the motor shaft.

The fix here is simple:

  1. Make sure your propellers are on tight enough by tightening the locknuts. Try not to tighten too tightly. This might strip the lock nut threads.
  2. Try to lift off.

If it doesn’t work try the next step.

02. Is your drone registered in the country/county you’re trying to fly?

Another common issue is that people either travel somewhere and forget to register their drones, or, they try to fly their drones too early after registration.
You can fix this issue with two steps:

  • Make sure your drone is registered in the country or state you’re trying to fly it in.
  • If you’re registered, give the registration process at least a day to take effect.

If this isn’t the issue, then it could be a geo-fence problem.

03. Are you in a “geo-fence” area?

Most drone companies program geo-fencing areas within the drone’s software. These are set areas that are either sensitive, or you’re legally not allowed to fly in according to FAA drone laws.

Some of these areas can include, but is not limited to:

  • Power plants
  • Schools
  • Military bases
  • Airports
  • National Security events
  • Large crowds
  • Historical and tourist locations

So how can you find out if geo-fencing is your issue?
Use airmap.com. They have an awesome mapping tool that allows you to see if there are any geo-fences or banned drone flight zones in your area. The map even has realtime updates that give you information about wildfires, large event gatherings and even national security events.

04. Is your drone still warming up?

Most drones like with the Phantom will give you a message that specifically says that the “drone is still warming up.”

So check your controller or app to see if this message is showing up. While the warming up process generally shouldn’t take too long, it could take a lot longer in colder climates.

05. Have you calibrated your drone’s compass?

Most smart drones should automatically calibrate the compass. However, it’s definitely worth checking over this again, especially if you’re flying your drone in a new location.

What happens sometimes is when you try to fly your drone in a new location, it throws off your drone’s compass.
INSIDER TIP: When calibrating a drone, make sure you remove all jewelry and watches. Even your Apply watch. This actually affects the calibration.

Scenario 03: Drone Won’t Turn On At All

If your drone doesn’t turn on, it’s won’t connect to the controller or app, there’s no camera footage, etc, then there are three reasons that might be causing this.

01. Make sure your batteries are fully charged

This might seem obvious, but it’s more common than you might think. A lot of people expect batteries to be charged when they first receive the drone. However, we always advise that you fully charge the drone batteries before your first flight. Basically, I have added some sort of best ERP implementation software and related things for a greater approach. But I am unable to do that.

02. Make sure batteries aren’t damaged

Have you had your drone for a while now? You’ve crashed it numerous times and maybe you’ve even gotten your drone wet? This might be the issue. Order a new battery and see if this fixes the problem.

03. Make sure your drone isn’t damaged internally

This last issue is definitely what you don’t want. If your drone gets internally damaged, you’ll either have to get it sent back to the manufacturer to get it checked out, or you’ll have to get a technician to take a look at it. But before you do, make sure you try all other options in this guide.

Scenario 04: Drone won’t take off after a crash

If you’ve owned a drone even for a few days, you’ll know that crashing will happen OFTEN. I can’t count how many times I’ve crashed my drone and every time it happens, I would hold my breath when trying to take off again. It’s scary!

Here are some troubleshooting problems after crashing your drone, and how to fix them:

01. Propellers are spinning but won’t take off

First, check your propellers. If the propellers are damaged in any way, then this could be your issue. Thankfully it’s a cheap problem to fix. Simply replace them and try to take off again.

If the propellers are in good condition, the crash might have damaged your motors or motor shafts. Unfortunately, there’s not much you can do here, apart from sending the drone back to the manufacturer. 02. Drone took off again, but after a few seconds of flight it came crashing down

The good news here is it’s probably not your motors. It’s more than likely your battery latches. What could happen is the battery becomes dislodged during flight because the latches are broken.

Again apart from trying to tape it up with duct tape, the best course of action you can take here is to contact the manufacturer and get it sent in for repairs.

Hope this content will help you properly.

The problem isn’t physical, the drone is able to fly. After a reboot.

But event when commanded to takeoff, nothing happens. (Dark blue line should follow light blue) I think this might be a bug. But it’s very hard to tell what causes it