black triangle heading west over pike county pa. during daytime with clear skies.

At 2:45 pm i was reclining at our community pool and my view was looking west. i saw something way up about 90 degrees over my head heading west. it was black and i initially thought it was a bird very high up. however as i followed it as it moved away from me i became sure it was a vehicle under control. first it was a black equilateral triangle. there were cirrus clouds in the blue sky and it would momentarily go behind them so i estimated it was about 20,000 feet up. it was the size of half my pinky finger nail or maybe an eighth of an inch. it did not waver in its flight path. it traversed about 120 degrees of sky in somewhere between 45 seconds and one minute. it made no sound. the area I was in is a forest community and very quiet apart from some children in the pool. once the object was past me i should have heard a low rumble of exhaust. but nothing. there also was no exhaust contrail. i went to my subscription of flightradar24.com and input the UTC ! time of 18:30 to 19:00 and nothing with a transponder was over my community at the time. 14:45 translates into 18:45 universal time.i consider the event anomalous.of course, i always watch the sky but when at the pool i leave my phone home so it wont get wet. and that is always when you see these things.