Legal reasons of wattage output is my guess. I'm sure his radio and fpv set up are over legal limits of the FCC. I can put my i1 on the back deck of my house and go sit in my workshop which is on the front side of the house and take off and fly to the front side of my workshop. So at start up signal is going thru 3 walls or up thru the roof and back down. I also have a metal roof on my place.
That could be part of it. The antenna when he landed looks like some sort of T-shaped affair and not like the stock one. I see Futaba was his sponsor so maybe they gave him some aid too.
Another thing is the FPV's don't have all the GPS/GEO and compass stuff so they can probably navigate around metal objects better too.
I was also curious of how close he was to that engineer who closed the window.
From his gear list, he listed the camera as this 1/3" sensor with a 150 degree field of view:
https://www.amazon.com/gp/product/B...6V8YZ&linkId=d52d13ffd16f2576c0363f34d4a74518
Using this field of view calculator for a 1/3" sensor and getting to their claim of a 150 degree angle of view (
Depth of Field, Angle & Field of View, & Equivalent Lens Calculator - Points in Focus Photography{%22c%22:[{%22f%22:0,%22av%22:%221.8%22,%22fl%22:0.8,%22d%22:1219}],%22m%22:0} ) I had to use a 0.8mm lens. At four feet, it would give one a 24' horizontal view of the train's lead engine so the FPV drone was pretty close to the cab to alert the engineer. The guy may have been able to swat at it if any closer.
So he was very, very close to the train do do the video with that camera setup. Probably not that much clearance between the steel bridge and train either to fly between them. Thing must be a flying gnat and some razor sharp reflexes of the pilot.
Fwiw, the guy won 1st place in recent Great Lakes Cup Championship too. If you want to see his take-off location, it's here as we've used it for butt-breaks on motorcycle rides from Truckee, CA to Reno, NV along I-80: 39.482921 -119.993854 His range check was .55 miles and distance to the bridge is about 500 feet so not that far, just the wide-angle makes it appear further. His training video shows some of them riding in a van following two flat bed semi-trucks with hoops on them to practice flying at moving objects, courtesy of Futaba too.