New York Times Investigative Reporter Eric Lipton tells Erin Burnett how his investigation revealed several key security features used for decades on Air Force One are not visible on new retrofitted j

By Mike Stone WASHINGTON, July 20 (Reuters) - The newly announced grounding of President Donald Trump's Qatari-gifted Air Force One jet is likely for security upgrades, experts said, though they questioned whether a month was enough time to significantly enhance the aircraft's defenses.

The jet had faced security concerns in the weeks since its first operational flight on July 1, when Trump flew on it to North Dakota.

US President Donald Trump said Sunday that the Qatari-donated jet that has served as Air Force One will be sent for upgrades, appearing to acknowledge the plane is not as thoroughly outfitted as older aircrafts.

The threat led the Secret Service to urge President Trump to fly out of Turkey on a different plane, raising questions about the security of the Qatari-donated jet.

President Donald Trump has unveiled the new Air Force One, a formerly Qatari-owned jumbo jet now converted into the official U.S. presidential aircraft.

Donald Trump flew on the new Air Force One, a luxury jet gifted from Qatar, for the first time. Here's how it compares to the old presidential plane.

President Trump flew to Michigan on Monday inside the classic Air Force One that now features a new painted color scheme. The plane is now dark blue with a gold stripe and red trim,