Narrative:

After all pre-flight checks and protocols were executed; the aircraft took off. Shortly after takeoff (~1.5 seconds); the aircraft was observed as acting in a strange manner (non-commanded oscillations and yaw movements). The pilot in command (PIC) reacted to the problem immediately and began the sequence for regaining control of the aircraft. 4 seconds later; the aircraft continued to ascend to ~35' AGL; still performing the uncharacteristic yaw/oscillation movements. It was the decision of the PIC (as per protocol) to land the aircraft immediately. The PIC was only able to control throttle at this point (5 seconds into flight). Therefore; he made the decision to decrease throttle at an extensive rate to land the aircraft abruptly. The aircraft landed ~50' from its original take off point. Total altitude throughout the entire mission was ~35'. The highest ground speed during the incident was ~5'/second. The aircraft performed an emergency landing. Although damage to the aircraft; 3rd party property was not damaged and no person (flight crew or otherwise) was physically harmed during the mishap. Preliminary analysis from the flight crew determined that there was a sensor issue triggered immediately after takeoff which induced uncommon aircraft characteristics. Further analysis of this issue will be performed to determine the root cause(s). The aircraft is currently not in an airworthy state and will not be flying until (1) the internal investigation is complete and (2) the flight crew has the necessary external approvals to do so.

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Original NASA ASRS Text

Title: UAV ground commander reported the drone flying erratically after takeoff.

Narrative: After all pre-flight checks and protocols were executed; the aircraft took off. Shortly after takeoff (~1.5 seconds); the aircraft was observed as acting in a strange manner (non-commanded oscillations and yaw movements). The Pilot in Command (PIC) reacted to the problem immediately and began the sequence for regaining control of the aircraft. 4 seconds later; the aircraft continued to ascend to ~35' AGL; still performing the uncharacteristic yaw/oscillation movements. It was the decision of the PIC (as per protocol) to land the aircraft immediately. The PIC was only able to control throttle at this point (5 seconds into flight). Therefore; he made the decision to decrease throttle at an extensive rate to land the aircraft abruptly. The aircraft landed ~50' from its original take off point. Total altitude throughout the entire mission was ~35'. The highest ground speed during the incident was ~5'/second. The aircraft performed an emergency landing. Although damage to the aircraft; 3rd party property was not damaged and no person (flight crew or otherwise) was physically harmed during the mishap. Preliminary analysis from the flight crew determined that there was a sensor issue triggered immediately after takeoff which induced uncommon aircraft characteristics. Further analysis of this issue will be performed to determine the root cause(s). The aircraft is currently not in an airworthy state and will not be flying until (1) the internal investigation is complete and (2) the flight crew has the necessary external approvals to do so.

Data retrieved from NASA's ASRS site and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.