The Preflight Checks

To ensure a safe flight please note the following points:

Actor Check

See here for more information.

There was a Bug befor NGOS 0.60, which allowed proper testing only when all BLCs are connected first.

Sensor Check

Enter the the following commands in the shell:

• loop adc10     -> battery
  loop adc12     -> gyro / temperature (if you own HW-0.21 or HW-0.22)
  loop adc16     -> gyro / temperature (if you own a HW-0.20)
  loop adc24     -> barometer
  loop acc       -> accelerometer
  loop rc        -> rc-mixer output

When you turn the copter in your hand, do the values change? Do they change in the right range and direction?
You may use qNGctrl for better visibility as well.

If loop rc does not show rc-mixer signal output, then check it the rc-mixer's inputs used with the following commands:

• loop rc-sum    -> rc-mixer input rc-sum
  loop dsl uart0 -> rc-mixer input rc-dsl on uart0
  loop dsl uart1 -> rc-mixer input rc-dsl on uart1
  loop dsl dsl0  -> rc-mixer input rc-dsl on dsl0
  loop dsl dsl2  -> rc-mixer input rc-dsl on dsl1

If everything looks fine, you are about ready to fly but sure to do the following Range Check before!

Range Check

Perform a range-check before first flight!

1. Set a behavior that plays a melody while the rc-signal is lost:

   • behavior add while.rc.signal.lost(25) actor.play.melody(3) 

2. Verify the correct settings of the behaviors by entering

   • list behaviors 

   If the behavior appears store it with

   • conf store 

3. Check if the behavior works: Switch on your transmitter and your NG, then switch off the transmitter and your NG should start screaming immediately. If that does not happen there are 2 possibilities:
   1. The behavior doesn't work
   2. There is someone on your channel
4. Now perform the range check: Place your transmitter somewhere about 1m from the ground, leave the antenna inserted, switch the transmitter on. Now switch the NG on and start walking away from the transmitter, ensure that you are not standing between transmitter and copter.

   Always walk in the same direction, don't turn the copter around in your hand. If the NG starts playing the melody <50m you should rethink your antenna construction! You may walk up to around 200m like this but you can stop after about 100-150m, without hearing the beeper and everything will be fine and you can do the following Pre-Flight Check.

Pre Spinup Check

Now that you have ensured that the RC-Connection between your NG and the Transmitter is working correctly you have to look at the UAV mechanics:

1. Check the propellers, do they have any damage? Are they discolored around the hub? if so -> change

2. Check the connection between propeller and motor, is it possible to turn a propeller without turning the motor? if so -> lock it! loose screws can be locked with Loctite 2701 for example. Don't forget also to check any propeller mounting equipment. Are the Props mounted for the correct direction (Clockwise vs Counterclockwise)?

3. Check the motors, are they mounted well to the frame? some motors have stand-off mounts, f.ex the DAT 750 or the CF2822, check if you have slippage in it. if so -> lock it!

4. Check if there are any wires in the prop-range, the antenna and the balancer cable are special candidates!
5. Check if all plugs are connected correctly and secured against accidential disconnection (this applies to the sensor-breakouts, too)
6. Check if the battery is mounted firmly, a loose battery can fall out of the copter, for more grip you may use table tennis rubber or sponge

7. Check the motors, do they make any abnormal sounds when you turn them by hand? if so -> change bearings and check if there is dust or some kind of pebbles between the stator and the magnets. A good place for buying bearings is Causemann.

8. Check the battery status of your transmitter, starting with an empty transmitter battery is absolutely negligent!
9. Check the antenna of your transmitter, if its loose screw it in and pull it out all the way!

Spinup Check

At first hold your NG with your hands while starting the motors! That way it will not flip and break before the first liftoff. It might be easier to hold the NG from above then from below, and push it back to the ground if anything goes wrong. For medium to large copters, the copter may be to powerful to hold it with the force of your wrist.

Make sure NOT to touch the moving propellers! It will hurt! Wear clothing that covers at least your arms.

Verify that you have the required liability-insurance for your NG and that the insurance has accepted you (and you have paid the insurance).

Make sure to choose a room or an area for the first spinup where you can do no damage. Glass stores and large Carparks are generally a bad idea. Your living-room may contain items that a person near you thinks valuable, too...

1. Powerup your RC, powerup your NG. Then move the Throttle/Yaw stick to the top left corner. This Calibrates your Gyros and should be done before each flight. Now move the stick to the lower right corner. This will start the spinup phase of the chosen controller. When activated your NG should spin up its motors within 2 seconds (default parameter). Moving the Throttle/Yaw stick to the lower left corner will switch the motors off again. You should not get troubles up to this point since the chosen controller did not yet take control. In the spinup phase and until you activate the flight phase by moving throttle upwards, the controller is not yet activated.
2. Do all motors run quiet and without vibrations?
3. After spinup, the NG is ready and awaits activation of the controller's flight phase. You do that by moving the throttle stick a bit up. Listen carefully if the NG makes a beep here, if not you have forgotten the Jumper and you won't hear the battery warning!! As soon as you move the stick the NG flight controller leaves the spinup phase and starts controlling the motors. This is the moment you see if all works. If your NG tries to break out something is amiss. If it tries to stabilize and the LED blinks rapidly the controller works and you are in state "flying".

4. If you turn the NG in any direction, you should feel the NG working against your movements.
   If not, check if the props are mounted for the correct turn-directions, the motors are turning in the right directions, the controllers are mounted with the IDs assigned in the correct order and the Sensorboard is oriented correctly related to the controller-IDs.

5. Set the NG on the ground, and turn throttle down all the way. Move the Nick/Roll stick until you see a reaction, and verify that the reaction is into the same direction as you expect.

You can always spindown the motors by moving the throttle stick on your remote to the lowest possible position and then to the left. Note that this won't work if you have no remote-control reception (cut antenna, sender battery empty, receiver cable damanged/unplugged, ...)

Congratulations! Your NG is ready for a real test flight!