23. A Flight - more than 120m above ground level - permissions must be obtained and shown in your posting - 3 points
I tried this a few ways—both flights and explanations—until I could find the most simple way to fly and try explain it. It still sounds complicated, sorry.
TL;DR
Flew drone 124.4m AGL near Ovingdean cliff. Using Pythagoras, distance to cliff face (closest point of the earth’s surface) was 96.98m—within the UK Drone Code’s 120m limit. Photo evidence includes aerial shots and app screenshots at various heights.
I didn’t seek special permissions from a building owner, I’m saying I obtained permissions when I got my Operator ID and Flyer ID, and I’m showing how the UK Drone Code allows my flight if flying where there are cliffs.
The Drone and Model Aircraft Code on 1 Aug 2023 said “Flying where there are hills, mountains or cliffs Your drone or model aircraft must never be more than 120m (400ft) from the closest point of the earth’s surface.“
I flew at 124m above ground level, but was less than 120m from the closest point of the Earth’s surface, because I was close to a cliff.
The flight was as follows: I was stood on a concrete path close the to bottom of the cliff, and I’m calling this ground level. I took off, flew straight up (no forwards/backwards/sideways movement) pausing at various heights to take photos and screenshots, then landed pretty much on the spot from where the drone took off.
I’m providing an aerial photo at 124.2m, screenshots, and an Airdata share link.
Drone photo was taken at 124.2m, the EXIF data says 124.2m
Screenshots show DJI Fly App, with screen saying the drone shown 1.1m (waist height), 29m (cliff height), 124m (max height)
Airdata seems to support what I’m saying: On ground shown as 0m. Very low hover shown as 1.1m. Cliff height 29.4m. Maximum height reached 124.4m AGL.
The cliff at Ovingdean West Sussex feels like it’s as near as damnit straight up and down. However it’s not perfectly vertical so I have taken this in to account in the maths. I took a straight down drone photo to get the lie of the land, and I estimate the horizontal distance from the top of the cliff to its bottom looks like 5 road lane widths so 20m.
I took a horizontal drone photo just below the top edge of the cliff, the drone was as 29.5m. I estimate the vertical distance from the top edge of the cliff is 124.4m - 29.4m = 94.8m.
So if the drone is 94.8m above the nearest terrain (cliff face) and 20m away from it (horizontally), we can use Pythagoras’ theorem to find how far away on the diagonal. If the adjacent sides are 94.9 and 20, square root of (94.9 x 94.9 + 20 x 20) is 96.98m.
In conclusion my claim is the drone was 96.98m from the closest point of the earth’s surface (permitted by the Drone Code), while at the same time it was 124m above ground level (meeting what’s required by the task). Coincidentally this was discussed by GADC members (unprompted by myself) after I made the flight in Drone off a Cliff edge
DRONE PHOTO
Drone photo 124.2m AGL
Drone Code Aug 2023 from
https://register-drones.caa.co.uk/drone-code/the_drone_code.pdf
3 Screenshots to measure horizontal and vertical distances.
AirData log share:
124m above ground level, Cliff at Ovingdean
1 Aug 2023 DJI Mavic Air 2, on a windy day with 31mph gusts
I claim 3 points please