> For the complete documentation index, see [llms.txt](https://docs.deltaquad.com/tac/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.deltaquad.com/tac/flight/executing-and-monitoring-a-mission/emergency-procedures/during-takeoff.md). # During Takeoff ### **Toilet Bowling** Operator Action: **LAND or ALTITUDE** The vehicle should take off in a straight line after the first few meters. If the vehicle starts "toilet bowling" (circling up), the mission should be aborted and a sensor calibration must be performed. If an autonomous landing does not stop the toilet bowling behavior, **ALTITUDE** mode should be engaged for a manual landing. ### **Not Holding Position** Operator Action: **LAND or ALTITUDE** The vehicle should take off in a straight line. If the vehicle starts drifting from its position by more than a few meters, it should be commanded to **LAND**. Contact support to have your log files analyzed. If an autonomous landing cannot safely be performed, **ALTITUDE** mode should be engaged for a manual landing. **When operating in GNSS-Denied mode, some drift is expected above 10 meters.** ### **Takeoff Failure** Operator Action: **DISARM (Emergency Action -> SHUTDOWN)** If the vehicle fails to take off or only one-half of the vehicle rises, the VTOL propellers are likely damaged, mounted incorrectly, or upside down. The operator should disarm the vehicle and review the propeller configuration as described in the [manual](/tac/maintenance/propeller-replacement.md). --- # Agent Instructions This documentation is published with GitBook. GitBook is the documentation platform designed so that both humans and AI agents can read, navigate, and reason over technical content effectively. Learn more at gitbook.com. ## Querying This Documentation If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question. Perform an HTTP GET request on the current page URL with the `ask` query parameter, and the optional `goal` query parameter: ``` GET https://docs.deltaquad.com/tac/flight/executing-and-monitoring-a-mission/emergency-procedures/during-takeoff.md?ask=&goal= ``` `ask` is the immediate question: it should be specific, self-contained, and written in natural language. `goal` is optional and describes the broader end goal you are ultimately trying to accomplish on behalf of the user. GitBook uses it to tailor the answer towards what is most useful for that goal. The response will contain a direct answer to the question and relevant excerpts and sources from the documentation. Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.