WASHINGTON-Federal investigators said the temporary relocation of Marine One's landing zone due to White House construction was a factor in a safety incident earlier this month involving the military helicopter carrying President Trump.
On Aug. 4, Marine One took off from the White House, bound for Joint Base Andrews in Maryland. Air-traffic controllers didn't halt commercial flights at Reagan National as required under safety protocols, The Wall Street Journal reported.
A preliminary report released by the National Transportation Safety Board on Thursday said the temporary relocation of Marine One's departure take-off location to the Ellipse - where it "was temporarily operating from while construction was ongoing at the White House"-prevented an adequate "line-of-sight to ensure communications."
The White House didn't immediately respond to a request for comment on the report.
Not all of the radio transmission from Marine One pilots were heard by air traffic controllers at the airport. Some of the transmissions were captured by a commercial app used by aviation enthusiasts, but not the tower, NTSB said in its report.
The report also says that Marines tried to give a three-minutes-to-take-off warning to controllers another way and that failed too.
The report says that the collision avoidance system went off in a regional jet that took off at the airport, warning of the helicopter. It estimates Marine One and the regional jet were 0.8 miles apart laterally and about 700 feet apart vertically.
President Trump began construction of a new granite helipad at the White House shortly after the UFC fight at the White House in June, adding it to a list of construction projects the president is overseeing. Trump is also building a ballroom at the White House and revamping the northern entrance to the building, which is currently covered in scaffolding.
The construction at the White House has required a change in the location of the helicopter departure from the south lawn of the White House to The Ellipse, which is slightly further south.
Federal aviation officials have moved air-traffic control antennas and are implementing new procedures to avoid a repeat of the safety incident with Marine One.
The planned changes, which also include boosting radio signals, aim to reduce potential communications interference at Ronald Reagan Washington National Airport and ensure controllers clear the airspace of commercial traffic before the president's helicopter takes off, the Journal has reported.
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