Adams Air Force Base

 is a heavily fortified Enclave settlement outside the Capital Wasteland, available in the Broken Steel add-on for Fallout 3. The base can only be accessed through the Presidential Metro and is not accessible before you have reached the appropriate point in the quest line. The base is a separate, new area outside of the Capital Wasteland. It appears to be as big as the locations from the previous add-ons The Pitt and Operation: Anchorage.

Related quest: Who Dares Wins
During the Who Dares Wins quest the player is sent to wipe out the remaining Enclave soldiers in the Capital Wasteland at Adams Air Force Base. The base contains a mass of Enclave soldiers, as well as standard defenses such as sentry bots and automated turrets.

Notable loot

 * There is a mini nuke, a first aid box, and some microfusion cells located in a nook above an awning that is reachable from the roof with a walkway covered in steel colored pipes. During the quest Who Dares Wins this roof will overlook a large number of Vertibirds. When coming from the Presidential Metro, keep moving right, and up some stairs. They are on a green tin awning at the far side of this roof. From the metal housing (with the computer and first aid kits) look right, towards the Vertibirds. The mini nuke and microfusion cells might not appear after completing the quest Who Dares Wins. If the military truck below the tin awning is destroyed, such as in a firefight with the Enclave, the resulting explosion may knock the mini nuke and microfusion cells to the ground below.
 * 400x flamethrower fuel - There is a holotape regarding flamer fuel that can be found on an Enclave scientist in the southeast research hanger. The message says that the fuel is located behind the small building due west of the Air Control Tower, beneath a pile of tires and barrels. It's behind the building, near the northwestern most corner of the area, in a very hard locked crate. The scientist with the holotape also carries the key to the stash. The barrels are on top of the crate and you may have to pull 1-2 of them off.
 * There is a mini nuke on the double-stacked large crates in Hanger 2B (the one with the covered catwalk patrolled by the sentry bot). It is highly recommended to clear out all Enclave personnel in and around the hanger and catwalk before retrieving it. Then hop onto the roof while walking up the south end of the covered catwalk, enter through the northwest hole in the roof and make a running jump (while standing) from the top of the cage to the stacked crates.
 * 2x mini nuke in a corridor of the aircraft hanger with three derelict jet planes inside. One is hidden under a desk, the other is hidden behind a filing cabinet.
 * Lots of scrap metal (30+ pieces). It is possible to find more than 100 pieces over the course of the Who Dares Wins quest in and around the base, altogether worth in excess of 1000 caps and at least 500 experience points if you sell them to Walter in Megaton for the Walter's Scrap Metal quest.
 * Lots of medical supplies including stimpaks and blood packs.
 * Enclave Soldier Log - located on a small platform behind a large machine, in the alley directly west of the rooftop where the Sector 2 Artillery Note is located. When in the alley and looking northward, turn left (west) and enter the opening between the walls. Following the alley, then climbing the stairs, there is a large machine. A dead Enclave soldier, a ripper, 2 psychos, a couple first aid boxes are all behind the machine, with the holotape on the Enclave soldier's body.
 * Lots of weapons in the Mobile Base Crawler's armory including an alien blaster (and ammo), a Precision Gatling laser, a heavy incinerator (and ammo), and a combat shotgun among a few others.

After the end of "Who Dares, Wins"
 * 2x Tesla cannon and 73x (roughly 100-115 with Scrounger) electron charge pack in a resupply crate on the back of a truck in front of the gates to the inaccessible area.
 * 2x Tesla cannon and 74x (roughly 100-115 with Scrounger) electron charge pack in a resupply crate in front of the fortification by hangar 4A.
 * 2x Tesla cannon and 74x (roughly 100-115 with Scrounger) electron charge pack in a resupply crate on the west side of the green crates outside the south end of hangar 2B.
 * 2x Tesla cannon and 74x (roughly 100-115 with Scrounger) electron charge pack in a resupply crate southeast of the Air Control Tower, surrounded by a semi-circle of sand bags.

Appearances
appears in the Fallout 3 add-on Broken Steel and is mentioned in Fallout: New Vegas from where ED-E was sent from.

Behind the scenes

 * This location is based on the real-life Joint Base Andrews Naval Air Facility formerly known as Andrews Air Force Base, and indeed, originally was to be named as such. Air Force One is situated at JBANAF. Evidence of this can be seen in the game files: the architecture meshes are in a folder named andrewsbase.

Background
Adams Air Force Base held a pivotal role in ensuring the safety of the United States Government's civilian and military officials if Washington, D.C ever came under threat of nuclear attack.

Government officials would be alerted by early warning signals of inbound Chinese nuclear devices. Officials could then quickly evacuate to Adams Air Force Base via the Presidential Metro and be flown to safety by the U.S Air Force.

Bugs

 * Sometimes wrecked Vertibird pieces hang in mid-air then drop out of the sky when approached.
 * In the alley that leads to the dead Enclave soldier with the Enclave Soldier Log #1, it is possible to become stuck behind the stairs, requiring either a reload of an earlier save or the use of console commands.
 * Sometimes after saving and exiting outside of the Mobile Base Crawler, upon reloading, The Enclave and BoS soldiers previously killed will come back to life wearing nothing. Killing and searching these soldiers will net more armor and weapons.
 * If the player enters Adams Storage Facility for the first time AFTER completing the quest "Who Dares Wins" and exits, this will trigger several Enclave units to spawn, almost always resulting in the game crashing soon after.
 * After retrieving your orders from the supply crate, and heading North-East to find the access terminal that lowers the ramp for the next part of the quest, it is possible to drop through a building, and land 'inside' said building. All textures will flicker as you walk, and you will be 'outside the map'. To do this, head North-East as intended, and take the walkway that flies over a building (the building it flies over has many pipes and generators etc. on the roof), and that hugs the wall of another building. Jump off the walkway on the side that hugs the wall, where the wall indents slightly. You should fall through. Once inside the building, however, you will become trapped, and will have to load from a previous save.
 * During the initial approach through the hangers, it is possible to skip going through the last few and quickly getting to the Brotherhood of Steel members. This can be done by going into one of the side hangers with many Enclave scientists within, jumping on a staircase railing, then jumping to a metal overhang, then through a hole in the hanger out onto the airstrip. Caution is advised though, as the player can shoot at and be shot at by the enclave from their small bunkers on the landing strip.
 * The Deathclaw cages can be lock-picked (Hard), then relocked using the attached Deathclaw Pen Door Terminal (needs to be hacked) multiple times, giving a lot of XP. (NOTE: Breaking the lock will also disable the terminal option to open the door)