A day before the tragedy unfolded in the skies above the Potomac River in Washington D.C ., another United States military helicopter reportedly came close to colliding with a passenger jet that had to abort its landing at the Ronald Reagan Washington National Airport due to a risk of a possible collision. Knewz.com has learned that the incident is one of many similar close calls in recent years, which have been the source of substantial concern about potential crashes. Around a week earlier,