This was a 7.5 acre land survey project flown for Magyar Surveying of Astoria and it was my first paid job on the Oregon Coast. Mike Magyar is a fantastic guy as well as a highly skilled surveyor and I look forward to much more work with him in the future. This was also the first job flown with my new Phantom 4 Pro UAV. For this project I used 6 Air Targets surveyed by Mike as my GCPs (Ground Control Points) for georeferencing the data set and set aside another 4 as checkpoints for accuracy. The dataset consisted of just over 1,000 photos flown at around 60-70 feet altitude giving me a ground sample distance (pixel width) of 0.23in. Thanks to the new UAS Facility Maps I knew that I could not legally fly over 100 feet in height anyway due to the nearby Astoria airport. The data set created from this imagery created a huge 165 million point cloud with an average density of nearly 750 points per square meter. After some point cloud cleanup and orthomosaic editing the data set was delivered to Mike who was very pleased with the results. My RMS Error (ft) was X = 0.012367, Y = 0.004687, Z = 0.028565 which created a very high resolution surface model for Mike to compare his survey points against as well.
There were some challenges to the job though!
1. Wind – Wow… afternoon wind on the Oregon Coast can really pick up! When I left the house Mike had texted me that winds were calm and weather was good but by the time I got to Astoria over an hour later the winds were gusting… and I was flying my brand new bird over ocean water at times along the shore!
2. Seagulls! Throughout the job gulls were dive bombing the P4Pro and I was just waiting for one to knock it out of the sky into the waves below! Thankfully, I’m fully insured!
3. Flight Restrictions – This was a challenging job as it was directly next to a busy thoroughfare running through Astoria. Without permission from the FAA I had to be very cautious not to fly over moving vehicles or pedestrians. I’m definitely looking forward to obtaining a waiver to do this in the future. In the mean time I need to plan my flightlines so that they do not cross above roads and I need to inform any pedestrians entering the AOI of the drone survey in progress.