BUD/S Phase 2 Length & What It Involves – Full Guide

Overview

BUD/S Phase 2 lasts 7 weeks and focuses on combat diving, underwater skills, and water confidence. Candidates train at Naval Amphibious Base Coronado, mastering open-circuit and closed-circuit diving, knot-tying, and small boat operations.

Phase 2 eliminates candidates who cannot perform under extreme physical and psychological stress in aquatic environments. It is the second of three phases in the Basic Underwater Demolition/SEAL (BUD/S) pipeline, governed by Naval Special Warfare Command (NSWC) under 10 U.S.C. § 5063 and OPNAVINST 5400.44A.

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Statutory & Regulatory Framework

BUD/S training operates under the authority of the U.S. Navy and Department of Defense (DoD). Key directives include:

• 10 U.S.C. § 5063: Establishes the Chief of Naval Operations (CNO) as the principal advisor on Navy operations, including SEAL training.
• OPNAVINST 5400.44A: Outlines Naval Special Warfare (NSW) policies, including BUD/S curriculum and safety standards.
• NAVSEA S9086-CN-STM-010: Provides diving and salvage manuals for military operations, including BUD/S diving protocols.
• SECNAV M-5210.1: Governs records management for BUD/S candidates, including medical and performance evaluations.

NSWC enforces these regulations through BUD/S instructors, who are active-duty SEALs with operational experience. Candidates must meet Medical Standards for Special Operations Forces (SOF), outlined in DoD Instruction 6130.03.

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Step-by-Step Process & Requirements

1. Arrival & Pre-Phase 2 Briefing (Week 1)

• Candidates report to Naval Amphibious Base Coronado and undergo a medical and gear inspection.
• Instructors review Phase 1 performance (Hell Week, physical screening test, and land warfare skills).
• Key requirement: Candidates must pass a 3-mile ocean swim in 80 minutes or less (wearing fins) to enter Phase 2.

2. Dive Physics & Theory (Week 1-2)

• Classroom instruction covers:
• Boyle’s Law, Henry’s Law, and Dalton’s Law (critical for underwater pressure management).
• Decompression sickness (DCS) symptoms and treatment.
• Closed-circuit diving (rebreather) principles.
• Candidates take written exams; failing twice results in dismissal.

3. Pool Competency (Week 2-3)

• Pool Comp is the most feared event in Phase 2. Candidates must demonstrate:
• Drown-proofing: Float for 5 minutes, swim 100 meters, and perform underwater knot-tying.
• Mask and regulator removal/replacement while underwater.
• Treading water with hands tied for 10 minutes.
• Failure to complete Pool Comp leads to immediate rollback or drop-on-request (DOR).

4. Open-Circuit Diving (Week 3-5)

• Candidates train in MK-16 rebreathers and SCUBA gear in San Diego Bay.
• Skills include:
• Underwater navigation (using compass and natural landmarks).
• Dive tending (assisting a buddy in distress).
• Small boat operations (inflatable boat handling, beach landings).
• Minimum dive depth: 40 feet; maximum depth: 130 feet (with instructor supervision).

5. Closed-Circuit Diving (Week 5-6)

• Candidates transition to closed-circuit oxygen rebreathers (MK-25).
• Key challenges:
• No bubbles: Must maintain stealth while diving.
• Oxygen toxicity management (risk of seizures if depth limits are exceeded).
• Emergency ascent drills (simulating equipment failure).
• Final dive test: A 2,000-yard underwater navigation course with a 90% accuracy requirement.

6. Final Evaluations & Transition to Phase 3 (Week 7)

• Land Warfare Review: Candidates must pass a timed obstacle course and weapons handling test.
• Medical Check: Ensures no decompression sickness (DCS) or ear injuries.
• Graduation: Top performers earn the Navy Diver (ND) insignia and advance to Phase 3 (Land Warfare).

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Common Pitfalls, Exceptions, & Penalties

Key Penalties:

• Rollback: Repeating Phase 2 (common for Pool Comp failures).
• Drop-on-Request (DOR): Voluntary withdrawal (no stigma, but no re-entry).
• Medical Discharge: Permanent disqualification for injuries like pulmonary barotrauma.

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Frequently Asked Questions (FAQs)

How long is BUD/S Phase 2?

BUD/S Phase 2 lasts 7 weeks, including dive theory, pool competency, open-circuit diving, and closed-circuit diving.

What is the hardest part of Phase 2?

Pool Comp is the most challenging event. Candidates must perform drown-proofing, underwater knot-tying, and mask/regulator drills while instructors aggressively disrupt them.

Can you fail Phase 2 and still become a SEAL?

Yes, but you must repeat Phase 2 (rollback). If you fail twice, you are dismissed from BUD/S.

What happens if you panic during a dive?

Instructors immediately pull you up and assess your condition. Panic underwater is grounds for dismissal due to safety risks.

Do you get weekends off in Phase 2?

No. Candidates train 6 days a week, with Sunday reserved for gear maintenance and medical checks.

What gear do you use in Phase 2?

• MK-16 rebreather (open-circuit).
• MK-25 rebreather (closed-circuit).
• Dive computer (for depth/time tracking).
• Fins, mask, snorkel, and weight belt.

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Practical Next Steps & Checklist

Preparation Checklist

• ✅Swim 3+ miles weekly (focus on combat sidestroke).
• ✅Practice breath-holding (aim for 2+ minutes).
• ✅Study dive physics (Boyle’s Law, Henry’s Law).
• ✅Master knot-tying (bowline, square knot, clove hitch).
• ✅Get a hyperbaric physical (check for ear/sinus issues).

Official Contacts & Resources

• Naval Special Warfare Preparatory School (NSW Prep): www.sealswcc.com
• BUD/S Medical Screening: 1-800-NAV-RECR
• NSW Recruiting Directorate: 619-437-2878
• Dive Manual (NAVSEA S9086-CN-STM-010): www.public.navy.mil

Disclaimer: This article is for informational and educational purposes only. It does not constitute formal military advice and does not guarantee BUD/S success. Always consult official Navy sources for training requirements.