Last week at our MTS Innovation Day, we had a great conversation about drone payloads, specifications, and efficiency.
It started with the kind of question we all ask: “If I fly Sensor X at 300 feet, is it more efficient than Sensor Y at 300 feet?”
It seems like a perfectly reasonable comparison.
But is it the right comparison?
I think there are really two ways we need to look at sensor efficiency.
The first is simple: same altitude versus same altitude.
Put two sensors at 300 feet AGL, look at their field of view, calculate their ground swath and determine how many flight lines each need to cover the project.
That tells us something important about coverage.
But it doesn’t necessarily tell us which system is more efficient.
Why? Because they may not be producing the same result.
One camera might have a much wider field of view and cover substantially more ground, while the other is producing a significantly better GSD.
We’re comparing acreage, but we’re not necessarily comparing equivalent deliverables.
That leads to what I think is the more interesting question: What happens when we require both systems to produce the same GSD?
Now we’re comparing the sensors based on the result the customer needs.
We recently ran the numbers using a CHCNAV AA6D dual-camera system and a DJI Zenmuse P1 with a 35 mm lens.
At 300 feet, the P1 produces roughly a 1.15 cm GSD.
To produce approximately that same GSD, the AA6D needs to fly considerably lower—around 160 feet AGL.
You might assume that flying almost 140 feet lower would eliminate the AA6D’s coverage advantage.
It doesn’t.
The AA6D’s two-camera configuration provides a combined 110° field of view. Even at the lower altitude, it still produces a ground swath of roughly 458 feet, compared with approximately 308 feet for the P1 at 300 feet.
At 60% sidelap, that translates to flight-line spacing of roughly:
- AA6D — 183 feet
- P1 — 123 feet
That’s nearly a 50% difference in effective flight-line spacing while targeting essentially the same GSD.
Now we’re talking about efficiency in a way that matters.
- Fewer flight lines.
- Fewer turns.
- Less acceleration and deceleration.
- Potentially fewer battery changes.
- Less time over the project.
- And ultimately, more acres collected in a working day.
Does that make one sensor “better” than the other?
No—and that’s really the point.
Every sensor is a collection of compromises: resolution, focal length, field of view, weight, altitude, speed, overlap, accuracy, point density, processing requirements and, of course, cost.
There isn’t a single specification that tells us which payload is best.
The question shouldn’t be: “Which sensor has the better specs?”
It should be: “What deliverable does my project require, and which combination of aircraft, sensor, altitude and flight plan gets me there most efficiently?”
That’s a much more interesting conversation—and exactly the kind of conversation we enjoy having at MTS.