Youll Know It When It Happens

After talking with Ranger Grant, head upstairs and speak with engineer Allison Valentine about her missing friend.

Return to the ground floor and enter the Supply Closet. Investigate the blood on the ground with a Perception 6 check to discover an NCR engineer has likely been killed and impersonated.

Hack the terminal in the Visitor’s Center (Average difficulty) and check the “Security Duty Roster” to learn about a potential sniper.

Head upstairs to the observation deck (south of Allison Valentine) and speak with Ranger Grant. Ask about the President's arrival to trigger the appearance of Bear Force One.

Option 1: End the quest quickly. Turn south-south-west, climb a ladder, and wait for the Vertibird to land. Search the machine and pass a Repair 50 or Explosives 50 check to find a bomb. Inform Ranger Grant in the Visitor's Center about the bomb; he will cancel the speech and send the President home.

Option 2: Deal with assassination attempts. If you choose not to tell Ranger Grant about the bomb (but disarm it if possible), head north-north-east past the Vertibird to the edge of the tower. Equip a long-range weapon like Ratslayer or the Gobi Campaign Survival **Sharpshooter Rifle**. Watch the northern tower; when another person arrives and dispatches the ranger there, kill the newcomer (a Legion sniper in disguise).

After dealing with the sniper, tell Ranger Grant. Focus on the crowd below Kimball. An engineer who previously tampered with the Vertibird will appear. If they move towards the President, shoot them. They will attempt to stab a ranger and then Kimball if you don't intervene. Kill the engineer to secure the President's safety.