Phase 71: Missile & Carrier Ops Completion¶

Status: Complete. 46 tests across 4 test files. 5 source files modified, 0 new source files.

Goal: Close the two largest remaining engine gaps — missile flight-to-impact resolution and carrier air operations. Fix 2 pre-existing bugs.

Changes¶

71a: Bug Fixes (2 pre-existing issues)¶

_sim_time_s UnboundLocalError (engine.py): Phase 69 introduced _cur_day_69a = int(_sim_time_s / 86400) for daily sortie reset, but _sim_time_s wasn't assigned until 20 lines later. Moved _sim_time_s = ctx.clock.elapsed.total_seconds() before the daily reset check. Removed duplicate assignment. This bug caused 15 scenario failures.
Missing launcher_id/missile_id in engagement.py: COASTAL_DEFENSE and AIR_LAUNCHED_ASHM launch_missile() calls lacked required launcher_id and missile_id args (the MISSILE handler had them correct). Added launcher_id=attacker_id and unique missile_id to both.

71b: Missile Flight Resolution¶

Wired MissileEngine.update_missiles_in_flight() into battle.py execute_tick (step 4h, after movement and before engagement):

Per-tick flight update advances all active missiles and resolves impacts
GPS accuracy from SpaceEngine feeds into CEP dispersion
Impact damage applied via _apply_aggregate_casualties() to nearest unit within 100m
Gated behind existing enable_missile_routing flag

71c: Missile Defense Intercept¶

Instantiated MissileDefenseEngine on SimulationContext and wired intercept checks:

Added missile_defense_engine field to SimulationContext
Instantiated in _create_engines() with COMBAT RNG stream
Per-tick: for each active missile, AD units (identified by SAM/CIWS/MISSILE_LAUNCHER weapon category) attempt intercept
Cruise missiles → engage_cruise_missile() (with sea-skimming penalty)
Ballistic missiles → engage_ballistic_missile() (layered defense)
Successful intercept deactivates missile before impact resolution

71d: Carrier Ops Battle Loop¶

Wired CarrierOpsEngine into execute_tick (step 4i):

Added enable_carrier_ops: bool = False to CalibrationSchema
Per-tick CAP station updates (endurance tracking, relief flagging)
Carrier unit identification by unit_type containing "carrier" or "cv"
Sortie rate computation based on aircraft count, crew quality, weather
Beaufort > 7 suspends flight operations
Structural wiring only — no current scenarios have carrier units

Files Modified¶

File	Changes
`simulation/engine.py`	71a-1: Fix `_sim_time_s` ordering
`combat/engagement.py`	71a-2: Add launcher_id/missile_id to 2 call sites
`simulation/battle.py`	71b: Missile flight + impact; 71c: Missile defense; 71d: Carrier ops
`simulation/scenario.py`	71c: Add missile_defense_engine field + instantiation
`simulation/calibration.py`	71d: Add enable_carrier_ops flag
`tests/validation/test_phase_67_structural.py`	Add enable_carrier_ops to deferred flags

New Test Files¶

File	Tests
`tests/unit/test_phase_71a_bugfixes.py`	8
`tests/unit/test_phase_71b_missile_flight.py`	12
`tests/unit/test_phase_71c_missile_defense.py`	12
`tests/unit/test_phase_71d_carrier_ops.py`	14
Total	46

CalibrationSchema Fields (1 new)¶

Field	Type	Default	Purpose
`enable_carrier_ops`	`bool`	`False`	Gate carrier flight ops processing

Design Decisions¶

Missile target resolution via spatial proximity: Missiles guide to target_pos, not target_id. Nearest unit within 100m of impact point receives damage. Realistic — weapons guide to coordinates, not entities.
AD unit identification by weapon category: SAM/CIWS/MISSILE_LAUNCHER heuristic. Simple, correct for current data, extensible without schema changes.
Carrier ops structural-only: No scenarios have carrier units. Wiring exercises the API path but won't affect outcomes until carrier units are added. Flag defaults to False.
Reuse existing enable_missile_routing for flight + defense: No additional flag needed — missile defense is meaningless without missile flight.

Postmortem¶

Delivered vs Planned¶

The plan spec (development-phases-block8.md) described 71a/71b/71c as three substeps. Implementation reorganized into 71a (bug fixes, unplanned), 71b (missile flight), 71c (missile defense), 71d (carrier ops). The bug fixes were discovered during planning and added as 71a.

Scope delta: - Added: 71a bug fixes (2 pre-existing issues) — unplanned but essential - Added: MissileDefenseEngine instantiation on SimulationContext (plan assumed it was already there) - Simplified: Carrier ops — plan specified sortie dispatch and recovery windows. Implementation covers CAP + sortie rate + sea state gating. Recovery window management is structural but not scenario-exercised. - Renamed substeps: Plan had 71a/71b/71c → implementation is 71a/71b/71c/71d (4 substeps instead of 3)

Verdict: Scope well-calibrated. 46 tests vs ~32 planned (+44%).

Integration Audit¶

Check	Result
`update_missiles_in_flight` called in battle.py	PASS
`missile_defense_engine` on SimulationContext + instantiated	PASS
`enable_carrier_ops` in CalibrationSchema	PASS
`enable_carrier_ops` in structural test deferred list	PASS
No TODOs/FIXMEs in modified files	PASS
No dead modules	PASS — no new source files

Test Quality¶

Mix: 71a all structural (source inspection); 71b/c/d mixed behavioral + structural
Statistical rigor: 50-trial GPS accuracy sweep, 30-trial high-Pk check, A/B sea-skimming comparison
Edge cases: Zero aircraft, zero Pk, Beaufort > 7, multilayer defense
Weakness: Structural tests tightly coupled to variable names (_m71.active) and log messages ("flight ops suspended") — fragile to refactoring but acceptable for integration verification

Deficits¶

Carrier ops untested in scenarios — enable_carrier_ops is in _DEFERRED_FLAGS. Will be exercised when carrier scenarios are added. (accepted limitation — structural wiring is the deliverable)
AD Pk hardcoded at 0.7 — The base intercept Pk for AD units is hardcoded. Should eventually read from weapon definition. (accepted limitation — below current scenario resolution)
No missile defense checkpoint state — MissileDefenseEngine has get_state/set_state but isn't registered with CheckpointManager. (deferred to Phase 72 — checkpoint completeness)

Documentation Freshness¶

All lockstep docs updated in this commit: - [x] CLAUDE.md Phase 71 entry - [x] development-phases-block8.md status → Complete - [x] devlog/index.md Phase 71 row - [x] devlog/phase-71.md (this file) - [x] README.md test count - [x] MEMORY.md status update

Summary¶

Scope: On target (slight expansion for bug fixes)
Quality: High — 46 tests, all passing, full suite green
Integration: Fully wired — all 3 engines connected to battle loop
Deficits: 3 items (all accepted/deferred)
Action items: Update lockstep docs → done