Flight Planning Basics

Ideal Flight Conditions

• Darker, overcast days and morning/evening flights may require a slower flight to prevent image blur given the requirement for increased exposure time.
• Ideal conditions for data collection are sunny or overcast skies (uniform lighting conditions), within a few hours of solar noon.
• If it is too dark to see your shadow, it is likely too dark to collect high-quality data. The sensor is measuring the interaction of plants with sunlight; darker conditions result in longer sensor exposure times, and thus slower flight speed to prevent image blur. If flying in overcast or darker conditions, decrease flight speed to compensate, especially if flying at low altitude or collecting population data.
• SlantRange sensors are not designed to be waterproof; do not fly in the rain!

Flight Planning Basics

SlantRange sensors are compatible with many third-party flight planners. The following best practices apply regardless of the specific flight planner you choose. 

SlantRange Tip: We recommend using Measure Ground Control for your flight planner. 

• Track crop growth stages closely, and fly in the correct stage for the desired data products.

Plant leaves CANNOT be overlapping for accurate stand counts; in corn, this is typically V2.

• Fly with sufficient resolution for the smallest feature to be measured.

4P+: from 165ft (50m) altitude, ground sample distance (GSD) is .4in (1cm). For high-quality data, flying at an altitude that gives several pixels per leaf is recommended.

• For Aerial Phenotyping, use the altitude, speed, and overlap settings from the assigned Flight Profile for the crop stage:

Tolerances are increased in cloudy conditions to maintain data quality: lower speed and altitude, and increase side-overlap

• Create and cache maps on your tablet with background satellite imagery for offline use
• Overfly the field in both dimensions to ensure complete coverage

In the pattern shown below, the North and South field boundaries are imaged in two flight passes. The side-overlap region of the first two and last two flight legs cover the length of the edge.

On the East and West edges, the aircraft overflies the length of the field, giving the aircraft time to stop, turn, and begin a new straight and level pass before imaging the data needed. Images taken in turns with high pitch and roll angles, where the sensor is not pointed nadir, are typically not suitable for map generation.

SlantRange Tip: When you're ready to fly a mission, follow this pre-flight checklist to ensure you're set up for a successful data collection. 

Post-Flight Data Quality Check

• Upon landing, verify AIS light is still blinking green. Or if using Measure Ground Control has returned to its ready state. 

If not blinking green, data collection likely stopped mid-flight and may need to be reflown for complete coverage. Proceed to use the quality check tools to find where and why data capture ceased.

• Stop data collection by pressing the AIS button for one second until the yellow light is displayed
• Wait for the sensor to return to the ready state where all three AIS lights indicate RTK status, then power down the aircraft.

For multi-battery missions, swap the batteries, and cycle through the flight steps again.

SlantRange Tip: Once you've finished powering down your sensor, run a data quality check from the field.