# Weather Conditions

## Heat

When operating in high-temperature environments, special attention must be given to the cooling and storage conditions of the DeltaQuad Evo:

* **Airflow Requirement:**\
  If the ambient temperature exceeds **25°C for more than 5 minutes**, the DeltaQuad Evo must be placed in an environment with **at least 2 m/s airflow** to prevent overheating of internal components.
* **Direct Sunlight Exposure:**\
  The aircraft **must not be exposed to direct sunlight for more than 5 minutes** while idle. Prolonged exposure can cause excessive heating of internal systems. It is **best practice to provide shade** for the aircraft during pre-flight preparations.\
  During flight, the Evo benefits from sufficient natural airflow to maintain stable operating temperatures, even in direct sunlight.
* **Storage Conditions:**\
  Always store the Evo in a **stable ambient temperature** environment. Avoid moving the aircraft directly from cold to warm conditions, as this may lead to **moisture condensation** inside sensitive electronics.

## Rain

Operations during rain are **generally not recommended**.

* **Tolerance:**\
  The DeltaQuad Evo is designed to tolerate **moderate rain (up to 7 mm/h)** while in flight. However, the aircraft **must not be launched during active rainfall**.
* **Airspeed Sensor Considerations:**\
  Exposure to rain during flight may result in **airspeed sensor failure**. In such cases, the onboard control system automatically switches to **fixed-thrust flight mode**, allowing the mission to continue safely. This mode increases power consumption and reduces maneuverability.
* **Post-Flight Procedure After Rain:**\
  If the airspeed sensor is affected by moisture or has failed due to rain, the aircraft **may not be relaunched within 24 hours** of the incident. Before the next takeoff, the airspeed sensor must be **verified to function correctly**.
* **Payload Considerations:**\
  **ISR payloads** may experience **reduced visibility or performance degradation** when exposed to rainfall.

## Fog / Clouds

The DeltaQuad Evo **must not be flown in fog**, and flight through **cloud layers should be minimized**.\
These conditions can lead to **unstable flight behavior** due to turbulence and may cause **moisture accumulation or ice formation** on control surfaces.

## Cold

Operation in cold conditions requires additional caution to prevent icing and control-surface obstruction.

* **Temperature Range Restriction:**\
  The DeltaQuad Evo **must not be flown between −5°C and +5°C** in the presence of **any atmospheric moisture** (e.g., fog, drizzle, or light rain).\
  Moisture in this temperature range can **freeze instantly on the wings, fuselage, or propellers**, leading to loss of lift and thrust.

## Active Snowfall

* **Do Not Fly:** The DeltaQuad Evo must **not** be launched or flown during active snowfall. Snow on propellers, sensors, or control surfaces can cause unstable flight and reduced performance.
* **Sensor Impact:** Snow can obstruct cameras, LiDAR, and other optical sensors, affecting navigation and ISR capabilities.
* **Post-Flight Check:** After exposure to snow, inspect and clear all sensors, propellers, and control surfaces before the next flight.
* **Freezing Risk:** Avoid flying near or below 0°C in snow to prevent ice buildup on the airframe, which can reduce lift and thrust or impair control.

## Snow and Mud

* **Takeoff and Landing:**\
  The DeltaQuad Evo **must not take off directly from snow or wet mud**, as these materials can adhere to the landing gear. Once retracted, they may **solidify or freeze**, potentially **preventing proper gear deployment** during landing.
* **Post-Landing Procedure:**\
  After operating in snowy or muddy environments, the **landing gear must be thoroughly cleaned** before subsequent missions.