Aircraft technician working on aircraft parked at gate reported being blown off ladder by jet wash from adjacent aircraft.

Narrative

I am an A&P; and as I was working on an aircraft getting a routine check underway; I went out to fill the Right Hand (#2) Engine with oil. I was in the process of filling the engine when out of nowhere the plane that was next to my gate had turned around and jet-washed me off of my ladder about 5 feet in the air. I got oil all over me and the engine as well as on the ground. The most frightening part was having to bail off of the ladder when I realized I wasn't going to be able to hang on any longer. If there is some sort of safety information that pilots should know about going full-throttle near and against an aircraft that is behind them; this pilot has no regards for others around them; I even had my safety beacon on in my vehicle that was right next to me in clear view of this aircraft. I even had the time to look up the aircraft that was next door to me on the gate. I am still shaken up by the experience and wish for none of my fellow employees operating on the ramp to have to experience something like this.