How altitude above mean sea level affects triggering of RTH

This article provides insight into how the flight altitude above mean sea level affects the triggering of automatic RTH. You’ll also learn about expected flight times and recommendations for maximizing flight time.

Air density decreases as the altitude above mean sea level increases. Lower air density means that WingtraOne motors need more power to generate the thrust required to make it fly. Increased engine power causes increased battery consumption. Another important factor to consider is air temperature. Air density decreases as the temperature increases. Flight time is also affected by humidity, payload weight, wind, hover time, and battery age.

Automatic RTH ensures that WingtraOne always has enough battery capacity to land safely. For more information about which parameters influence the failsafe RTH feature, please follow the link to this article Failsafe scenarios.

With the v1.9.5 software release, auto RTH works reliably at altitudes up to 3000m above mean sea level (AMSL) and you no longer have to manually trigger RTH to ensure a safe landing. This newest software release also enhances safety by factoring in the absolute altitude of the take-off location to determine a safe timing for automatic RTH triggering. For flights above 3000m, reliable RTH is not guaranteed. For more information about environmental condition requirements to ensure safe flights with your WingtraOne, please read the Environmental conditions article.

Guidelines for expected minimal flight time:

  • At 3000m AMSL  and 20m transition altitude at ~25°C = ca 20 min flight time
  • At 2500m AMSL  and 20m transition altitude at ~25°C = ca 25 min flight time
  • At 2000m AMSL and 20m transition altitude at ~25°C = ca 30 min flight time

To ensure maximal flight time at given altitude please make sure of the following:

  • The Transition altitude is as low as possible (How transition altitude impacts flight time)
  • The survey is as close as possible to the take-off location both in distance to the survey area (visual line of sight) and vertical distance to the survey altitude (not more than 120m above take-off location)

If the above mentioned settings do not allow your expected flight time, please contact Wingtra Support for further information and advice.

Starting from version 1.10 a new message is showing up when the altitude above mean sea level of the home point exceeds the 2500 m. This is a warning message to remind that the flight altitude is close to the limit of WingtraOne capabilities so that additional attention is given to the flight planning.

Screenshot_20191003-080234_highAltitude

When the altitude of the home point exceeds the 3000 m amsl, then another message informs the operator that flying in these conditions is unsafe and warranty is not valid in case of an incident.

Screenshot_20191003-075952_highAltitude_above3000