# X55 and Hybrid Module Setup and Operation

## X55 and Hybrid Module Setup

Some of these steps are repeated from the X55 Operation Manual, but this listing of steps is specific for the Hybrid Module Setup.

* Remove the X55 from the travel case or other storage position.
* Insert the landing gear into the landing gear mount and close the latches. Insert the safety pin into the landing gear mount and make sure the landing gear is fully secured.

![](https://2409858111-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2F1kam0V1LiqOorrn8CMy4%2Fuploads%2Fc0RBxVW6lMGrdGnTST31%2F0.png?alt=media) ![](https://2409858111-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2F1kam0V1LiqOorrn8CMy4%2Fuploads%2FdRRuejlko5CN7YEWXYDW%2F1.png?alt=media)

* Check and verify that there is no damage to the carbon fiber tube structure.
* Remove the arm holder clips. Unfold the arms and remove the prop protectors.

![](https://2409858111-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2F1kam0V1LiqOorrn8CMy4%2Fuploads%2FHaZcg5i1L8DI9ipXmBl4%2F2.png?alt=media)

* Secure the arms by tightening the knobs and securing the latches once fully tightened. The latch is a redundant safety mechanism to prevent the knob from coming loose during flight. Unfold the propellers and make sure they are straight.

![](https://2409858111-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2F1kam0V1LiqOorrn8CMy4%2Fuploads%2FMV8BdvGlrSzCcFhFmQTf%2F3.png?alt=media) ![](https://2409858111-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2F1kam0V1LiqOorrn8CMy4%2Fuploads%2FdBuwUf0H3891JRGK2AMO%2F4.png?alt=media)

* Check the propeller blades for damage, nicks, scrapes, or looseness/play. If a propeller blade has been nicked, it should be replaced. Check blade bolts and make sure they are tight.
* Check the Motors, make sure they spin freely, and that there is no scraping sound or grinding feeling.
* Place the Hybrid Module on top of the X55 and close all four latches.

![](https://2409858111-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2F1kam0V1LiqOorrn8CMy4%2Fuploads%2FDskPvQRHFRZZ8cXtUBiW%2F5.png?alt=media)

![](https://2409858111-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2F1kam0V1LiqOorrn8CMy4%2Fuploads%2F1qoiz8WSBTofIy7TZska%2F6.png?alt=media)

* Fill up the fuel tank to the desired level (see [“Filling the Hybrid Module Fuel Tank”](filling-the-hybrid-module-fuel-tank) section).
* Secure the payload to the payload rails of the X55.
* Check the Center of gravity (CG) by carefully picking up the drone from the Hybrid Module handles with one finger on each side (see arrows below), keeping your fingers aligned with the location of the landing gear leg mounts. Try to make adjustments (front/back) to move the CG to the center of the X55. Secure the payload to the payload rails once the CG is centered.

![](https://2409858111-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2F1kam0V1LiqOorrn8CMy4%2Fuploads%2FNEnIr1FW3IUYm0jiSxzP%2F7.png?alt=media)

{% hint style="warning" %}
Bringing the CG as close to the center of the X55 as possible will improve the controls of the X55 and minimize unequal motor output.
{% endhint %}

* Check that all antennas, GPS modules, payload mounts, and electrical connectors are secure.
* Turn on the remote radio controller and allow it to boot up completely. Always turn on the remote radio controller before powering on the Hybrid Module and X55. Open up the QGC application.
*   Plug the Main Power Cable into the “Power In” connector on the X55 and the “Power Out” connector on the Hybrid Module. The system will not power up yet.\
    \


    <figure><img src="https://2409858111-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2F1kam0V1LiqOorrn8CMy4%2Fuploads%2FqAArUw1sFIbHmJEsJP6v%2F9.png?alt=media" alt="" width="375"><figcaption></figcaption></figure>
*   When you are ready to turn on the system, make sure the Charge Bypass Switch is in the OFF/KILL position, and then swiftly plug in the On/Off Key to the Hybrid Module output panel. Wait at least 15 seconds before the next step and do not disturb the aircraft, as the sensor initialization process needs the airframe to be still for proper operation.

    ![](https://2409858111-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2F1kam0V1LiqOorrn8CMy4%2Fuploads%2FZTA7r5oTPRqL8HMqvcZc%2F10.png?alt=media)

{% hint style="warning" %}
If the Hybrid Module moves during initialization, the gyro sensor may not calibrate properly and will fail to start or give gyro-related warnings.
{% endhint %}

* After initialization of the aircraft, proceed to move the Charge Bypass Switch to the center (ON) position. You should hear a 1-2 second priming pulse from the fuel pump.
* When you are ready to start the engine, use the roto-start kit with the drill. Insert the bit into the hex adapter on the engine, making sure that the bit engages well with the starting mechanism. Hold the drill tightly, make sure it is in the fastest setting, and that it is set up in the counter-clockwise (CCW) direction. Spin start the engine, going for 5-10 seconds at a time, or until the engine starts.&#x20;



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* Allow the engine to idle for at least 1 minute, and observe the engine and the Hybrid Module to make sure there are no leaks or visible problems.

## Steps Before Takeoff

*   Check the fuel level of the Hybrid Module, which will be represented as a percentage in the GCS - make sure it corresponds with the actual level of fuel in the tank.\
    \


    <figure><img src="https://2409858111-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2F1kam0V1LiqOorrn8CMy4%2Fuploads%2FmJfLpaRghIeC1E9KKX7I%2F0.png?alt=media" alt="" width="375"><figcaption></figcaption></figure>
* On the ground station, make sure that the system voltage is at least 49V. If the system voltage is less than 49V, activate the Charge Bypass Switch (flip it upwards) and allow the system to charge fully. While the system is charging, the Status LED will be slowly blinking. After the system is charged, the LED will be solid. Turn off the Charge Bypass Switch (move it to the center position) after it is charged.
* Check the radio controller and GCS battery level, and make sure they are sufficient for the duration of the operation, or that a backup power source is available to keep them running for longer operations.
* Make sure the engine is running smoothly and listen/look for any abnormal sounds and sights.
* Double-check the failsafe settings to make sure they are as expected.
* Check that the buttons and switches on the radio controller are set correctly based on the desired flight modes.
* Verify that there are no flight warnings in QGC/Mission Planner, the EKF status is ready, and that there is a GPS fix.
* Manually check and make sure the propellers are clear to spin.

{% hint style="danger" %}
The X55’s props spin at a high rpm and can cause severe injury and damage. Always make sure the propellers are clear to spin and stay at least 5m away from the X55 during takeoff.
{% endhint %}

* Press and hold the arm switch for 2 seconds to pre-arm the X55. The LEDs on the GPS will turn blinking green, indicating that the X55 is ready for arming.

![](https://2409858111-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2F1kam0V1LiqOorrn8CMy4%2Fuploads%2FfgZZu1HtD29k0cKy65g7%2F2.png?alt=media)

## Takeoff and Pre-Mission Checks <a href="#pcox4rn4h6ol" id="pcox4rn4h6ol"></a>

* Select Altitude Hold Mode or Loiter Mode (preferred).
* To start the motors, hold the left stick at full low throttle and full right yaw to arm. Ensure the motors start to spin. At the same time, the act of arming the X55 will trigger the Hybrid Module to go into the RUN mode.

{% hint style="danger" %}
The X55’s props will start to spin at idle speed even if the throttle is all the way down.
{% endhint %}

* Apply power to lift off and ascend quickly off the ground (1-2 meters). Confirm the X55 feels stable and responds correctly to small stick inputs for pitch, roll, and yaw.
* Allow the system to hover in place for at least 30 seconds.
*   At the end of the 30 second hover, check the GCS to make sure the following data is within the range of normal:

    1. System Current - less than 53 Amps on average
    2. System Voltage - greater than 49V
    3. Fuel percentage - approximately matching the level in the tank. Additionally, make sure that no errors or warnings become active on the GCS before attempting to start a mission or manual flight.
    4. Proceed to the mission/desired flight mode with caution.



    <figure><img src="https://2409858111-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2F1kam0V1LiqOorrn8CMy4%2Fuploads%2FjLseCbbp3iA7Ojyxnqnt%2F4.png?alt=media" alt="" width="375"><figcaption><p>Fuel percentage check -approximately matching the level in the tank</p></figcaption></figure>

## During Flight <a href="#id-3krrx7qwht1w" id="id-3krrx7qwht1w"></a>

* Check the fuel percentage, voltage, and current readings at regular intervals if possible. Make sure they are consistent with the expected readings. For example, if the system is not overloaded, the system voltage should not generally be dropping below 49V. Additionally, the total system current should not be more than 50A. The fuel percentage should be decreasing according to the estimated flight time of the specific payload configuration (i.e. for a 3 pound payload, after 1 hour of flight, the fuel percentage should have gone down by about 50%, but not significantly more).
* Be alert to any warnings or errors that appear on the screen, and take the appropriate action, if necessary, or make sure that the appropriate failsafe actions are triggered.
* Ensure telemetry & radio controller link signal strength is within the operating limit.
* Be aware of meteorological changes during flight.
* Be aware of any manned/unmanned flights around the operation area.

{% hint style="danger" %}
The recommended landing fuel percentage is 15% or more
{% endhint %}

{% hint style="danger" %}
It is the pilot's responsibility to always maintain a visual line of sight with the X55, and to avoid flying over people, or near any aircraft. Use visual observers if necessary.
{% endhint %}

{% hint style="info" %}
If the system is not loaded with more payload than the Hybrid Module can supply power for, the system voltage will not decrease below 49V, and only the fuel percentage will decrease. However, in the event that the system is loaded with more payload than advisable, the batteries will begin to drain. In this situation, the standard battery failsafe actions will become active when the system voltage reaches these configured voltage levels.
{% endhint %}

{% hint style="danger" %}
Running with higher than advisable payloads decreases the available battery capacity, and is less safe in the event of an emergency.
{% endhint %}

## Descent, Landing, and Power Down <a href="#tss9mpeq7q8i" id="tss9mpeq7q8i"></a>

* Make sure the landing area is clear.
* Descend with a steady angled flight path towards the landing area, and avoid descending vertically into the downdraft.
* Slowly descend the X55 to touch down with minimal horizontal movement to avoid rollover.
* Upon landing, disarm the motors by holding the throttle all the way down and moving the stick to full left yaw. This will also trigger the Hybrid Module to transition into the IDLE operation mode.
* Ensure that all motors are stopped and disarmed before approaching the X55.

{% hint style="danger" %}
The Hybrid Module heat sink (on the front of the module) and exhaust muffler will be very hot after running the system. Avoid touching or making contact with these for at least 10 minutes after landing.
{% endhint %}

*   Press the arm switch to further disarm the X55 before approaching the vehicle.\


    <figure><img src="https://2409858111-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2F1kam0V1LiqOorrn8CMy4%2Fuploads%2Ftd8ZpLzQxMXO0KKgc3Rl%2F10.png?alt=media" alt="" width="262"><figcaption></figcaption></figure>
* Allow the Hybrid Module to IDLE for at least 1 minute to cool down, before killing the engine.\

* Kill the engine by flipping the Charge Bypass Switch to the downward position.\

* Turn off the system by removing the On/Off Key quickly.&#x20;

## After Each Flight <a href="#id-3a131gm61npq" id="id-3a131gm61npq"></a>

1. Inspect all motors for any signs of damage, grinding, or debris.
2. Inspect all propellers for any signs of damage or play.
3. Inspect all booms for any signs of damage/play.
4. Inspect landing gear for any damage or cracks.
5. Inspect the engine, exhaust, and wiring for any signs of leaks, damage, or broken connections.

## After the Last Flight <a href="#z1f17yu95n2o" id="z1f17yu95n2o"></a>

* Remove the AS120 plug that is connecting the Hybrid Module and the X55.
* Remove the Hybrid Module from the X55.
* Release the knob latches and unthread the knobs.
* Fold the propeller blades and install the propeller protectors to secure the propellers and prevent them from moving around.
* Fold the booms inwards and install the arm holder clips.

![](https://2409858111-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2F1kam0V1LiqOorrn8CMy4%2Fuploads%2FM9ZfOqkVEBSUKoNvpu9R%2F11.png?alt=media)

* Remove the landing gear and fold the antennas up for storage.

![](https://2409858111-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2F1kam0V1LiqOorrn8CMy4%2Fuploads%2FOtSmgDyQNNdQ5AE56vKD%2F12.png?alt=media)

* Place the X55 into the case carefully, and pay special attention to the GPS when putting the X55 into the travel case.\

* Wait for the Hybrid Module components to cool down for at least 5-10 minutes before placing the Hybrid Module back in its case.

{% hint style="danger" %}
We strongly recommend emptying the fuel tank before placing the Hybrid Module into the travel case to prevent fuel from sloshing/leaking inside the travel case. If you travel with the fuel in the Hybrid Module, take special care to not angle the case more than 20 or 30 degrees off of horizontal.
{% endhint %}
