In 2013 , conditions were such that a weather advisory was put out Judgment_communication to the 5,800 participants Participation to reconsider Deciding running Motion the race Competition if they had not trained Education_teaching in the heat or at higher altitudes and that officials were considering altering Change or canceling Removing the event .

The aircraft were in an area known as the `` Hudson River VFR Corridor '' , which extends Expansion from the surface of the river to altitudes of at various locations along the Hudson River in the immediate area of New York City .

The number of fighter aircraft and anti-aircraft guns assigned Choosing to defensive Defending duties in the home islands was inadequate , and most of these aircraft and guns had difficulty reaching the high altitudes at which B-29s often operated Control .

Much of the battle took place Process_start in harsh mountain conditions , entailing large-scale combat Hostile_encounter at altitudes of over 4,000 metres ( 14,000 feet ) .

It is now believed that the crew became Becoming confused as to their exact location while flying Self_motion at high altitudes through the ( then poorly understood ) jet stream .