The Prydwen

The Prydwen is a modified and armored Brotherhood of Steel airship that flies throughout the skies of the Commonwealth. The vessel serves multiple roles for the Brotherhood, including those of aircraft carrier, command center, clinic, personnel quarters, equipment maintenance bay and research facility. It is, for all intents and purposes, an airborne military base. It will be moored to the air traffic control tower at Boston Airport shortly after the Sole Survivor exits Fort Hagen during the quest Reunions.

Background
The Prydwen was constructed at Adams Air Force Base over a period of six years. It took an initial two years to collect the materials necessary and another four to actually construct the airship, and by 2287 had been in service for five years. It weighs forty thousand tons, as noted by Lancer Captain Kells and Elder Maxson. Before the journey to the Commonwealth, its original power plant has been replaced with an updated plant pulled from an old aircraft carrier.

The airship is filled with hydrogen, as stated during the quest Airship Down. Four pylons attached to the ship's flight deck carry a single jet engine each, being responsible for controlling the Prydwen's altitude and help to keep the ship aloft. There are four docking hooks for Brotherhood-modified VB-02 Vertibird gunships attached to the airship's hull. Vertibirds are accessible via the flight deck. Due to the combustible nature of hydrogen, the ship itself is not capable of combat, and this is stated by the crew.

Layout
The Prydwen is divided into two exterior areas and two indoor areas: the flight deck, the command deck, the main deck, and the forecastle.

On the main deck is a medical bay, mess hall, power armor station, crafting equipment, and a shop at the end of the corridor. There are also stairs that lead either up to the living quarters or down to a storage area. Around the perimeter and along the top are patrolled catwalks. The main deck is contained within the airbag, as the hydrogen is inside several canisters positioned around the outer hull.

The flight deck is located along the midsection of the gondola. There is a control room/storage area overlooking the deck, accessible at the back of the flight deck.

The command deck has three levels. The top level has Maxson's observation deck. The next one down is a storage area, with access to the forecastle. Finally, the bridge is at the bottom, where Lancer-Captain Kells can be found.

The forecastle is a small balcony that is accessible from the top of the command deck.

Inhabitants
The Prydwen's crew includes:

Optional crew members:
 * Predictive Analytic Machine, if reprogrammed in the mission Tactical Thinking.
 * Paladin Brandis, if convinced to rejoin the Brotherhood.
 * Madison Li, if convinced to join during From Within.
 * Professor Scara, if convinced to join during Liberty Reprimed.

Notable loot

 * BoS II T-60b power armor - Shadow of Steel quest reward.
 * Long range laser rifle - Found on the Prydwen's forecastle in a crate called sharpshooter stowage. The forecastle entrance is located through the main deck's southern top floor.
 * Three mini nukes can be found on the lower catwalk of the main deck, next to the mini nuke crates that are recovered from the Fort Strong armory during the quest Show No Mercy. Two are on top of the crates and the third is on the floor next to the northwestern crate.
 * X-01 power armor Mk1 helmet, Gauss rifle, Fat Man with two mini nukes, and a fusion core.
 * A large amount of ammo can be stolen from in Proctor Teagan's cage behind a Master lock.
 * Knight-Captain Cade's report - Holotape, in Cade's medical office, next to a terminal.
 * C.I.T. recon report - Holotape, left of the helm on the command deck, on top of one of the southern computer gauges.
 * Personal log - 142 - Holotape, on a nightstand on the east side opposite of the outgoing mail terminal.
 * Quinlan to be deleted - Holotape, on top of a file cabinet in Quinlan's office.
 * Maxson was right - Holotape, located on a nightstand between two beds above the entrance to get to the command deck.
 * Your new assignment - Holotape, on top of a barrel next to a bed, above the entrance to the main deck.
 * Nuka-Cola Quantum - On the main deck, lower catwalk.
 * Commando armor, Honor, Death from Above, Vengeance and Sentinel's Plasmacaster - All sold by Teagan. Honor and Death from Above become available after becoming a paladin, while Vengeance and Sentinel's Plasmacaster become available after becoming a sentinel.
 * Steadfast BOS combat armor chest piece - Reward for completing the quest The Lost Patrol if it is turned in to Kells instead of Danse.
 * Exemplar's T-60c torso - Reward from Kells for completing the quest Duty or Dishonor by persuading Clarke to turn himself in.
 * Visionary's T-60c helmet - Reward from Kells for completing the quest A Loose End.

Pickpocket or dropped on death

 * Eight complete BOS II T-60 power armor suits can be stolen - three from the patrolling sentries, three stationary sentries (main deck, flight deck, command deck) and another two from the power armor bay. (Note: The sentries will continue their patrols/manning their posts, but if they are killed, they will eventually respawn with new sets of armor.)
 * Prydwen armory key - On a Brotherhood knight-captain, near a small diner, the southern part of the ship.
 * Airship captain's hat and Brotherhood Officer Fatigues - Pickpocketed from Knight-Captain Kells.
 * Brotherhood medic fatigues - Worn by Knight-Captain Cade.
 * Bomber jack
 * Engineer's armor
 * Final Judgment - Unique Gatling laser, carried by Elder Maxson who also wears Maxson's battlecoat.
 * Medical goggles
 * Quinlan's armor - Pickpocketed from Quinlan.
 * Science scribe's armor
 * Teagan's armor - Pickpocketed from Teagan.
 * Welding helmet

Related quests

 * Shadow of Steel
 * Airship Down
 * Rockets' Red Glare
 * With Our Powers Combined

Behind the scenes

 * Prydwen (Middle Welsh lit. "fair-faced," "handsome") is the name of King Arthur's ship in the native Welsh literature concerning the legendary character. Arthur and his men board it to sail to the Otherworldly fortress of Annwn [pronounced; ah-noon] in the somewhat cryptic poem Preiddeu Annwfn [pronounced; Prey-they--Ann-oovn] as well as when they sail to and from Ireland in the prose text Culhwch ac Olwen in an attempt to gain a magical cauldron. It is not explicitly named in any other native Arthurian tale or poem, and in the Anglo-Norman literature that drew from it Arthur does not appear to have a comparable vessel.
 * It is pronounced by multiple characters in different ways. Military Frequency AF95 broadcasts pronounce it "preed-win" whereas Paladin Danse pronounces it "prid-win;" the Welsh pronunciation is "prud-when."

Bugs

 * Stealing from the Prydwen armory can result in all Brotherhood NPCs turning hostile against the Sole Survivor. This can happen regardless of whether the Survivor is detected or not and can happen even if a Stealth Boy is used. Solutions include picking up the desired item and moving it outside the armory before stealing it. This does not alert the Brotherhood.
 * This only happens if a very significant amount of loot is stolen.
 * Killing the Brotherhood lancer-sergeant on the northern Vertibird gantry may result, after a save and reload, in an invisible corpse with an untargetable version of the NPC standing over it. The invisible corpse may be looted, and may even be moved, but will revert to its original position on reload. No known fix, but ultimately harmless. This bug has also been seen on the scribes along the flight deck.
 * Following the completion of the quest Airship Down, the Prydwen will still appear as a fast travel destination in the Pip-Boy. Attempting to fast travel to the Prydwen will yield the message "Fast Travel is currently unavailable from this location" regardless of where attempted.
 * After killing Kellogg in the quest Reunions, the Prydwen may not be seen in the sky and Military frequency AF95 may not play. This can be fixed using the console command This will teleport you to the roof of the Cambridge Police Station and tell you to board the vertibird.