Maintenance: distance wear, broken-state burn ×1.5, repair action (ISS-069, v0.39.0)

lib/db/client.ts

@@ -31,7 +31,9 @@ CREATE TABLE IF NOT EXISTS planes (
   lat REAL NOT NULL,
   lon REAL NOT NULL,
   departure_sim_time INTEGER,
-  queue TEXT NOT NULL DEFAULT '[]'
+  queue TEXT NOT NULL DEFAULT '[]',
+  health REAL NOT NULL DEFAULT 100,
+  repair_until_sim_time INTEGER
 );
 CREATE TABLE IF NOT EXISTS packages (
   id TEXT PRIMARY KEY NOT NULL,
@@ -88,6 +90,14 @@ function migrateColumns(raw: RawSqlJsDatabase): void {
   if (!cols('packages').has('special')) {
     raw.exec('ALTER TABLE packages ADD COLUMN special TEXT');
   }
+  // v0.39.0 (ISS-069): plane health — pre-existing rows backfill to full health.
+  if (!cols('planes').has('health')) {
+    raw.exec('ALTER TABLE planes ADD COLUMN health REAL NOT NULL DEFAULT 100');
+  }
+  // v0.39.0 (ISS-069): repair gate — nullable, no default; pre-existing rows stay NULL = not in repair.
+  if (!cols('planes').has('repair_until_sim_time')) {
+    raw.exec('ALTER TABLE planes ADD COLUMN repair_until_sim_time INTEGER');
+  }
   // v0.30.0 (ISS-057): last-selected speed — pre-existing rows backfill to the row's OWN
   // current time_scale so a legacy DB resumes at the speed it was running, not the default.
   if (!cols('sim_state').has('last_selected_time_scale')) {

lib/db/schema.ts

@@ -7,7 +7,9 @@ import { integer, real, sqliteTable, text } from 'drizzle-orm/sqlite-core';
 export const planes = sqliteTable('planes', {
   id: text('id').primaryKey().notNull(),
   model: text('model').notNull(),
-  status: text('status', { enum: ['available', 'flying'] }).notNull(),
+  // v0.39.0 (ISS-069): 'repairing' = grounded in the shop until repairUntilSimTime passes; the
+  // engine flips it back to 'available' on a tick. All status guards key off 'available'.
+  status: text('status', { enum: ['available', 'flying', 'repairing'] }).notNull(),
   fuel: real('fuel').notNull(),
   maxFuel: real('max_fuel').notNull(),
   locationIcao: text('location_icao').notNull(),
@@ -24,6 +26,12 @@ export const planes = sqliteTable('planes', {
   // of ICAO strings ('[]' when empty). The ACTIVE leg stays destIcao +
   // departureSimTime; on landing the engine auto-chains queue[0] if fuel covers it.
   queue: text('queue').notNull().default('[]'),
+  // Structural health in [0, 100] (v0.39.0, ISS-069) — wears down by WEAR_PER_KM per km of
+  // landed legs; at 0 the plane is broken and burns BROKEN_BURN_MULTIPLIER × more fuel.
+  health: real('health').notNull().default(100),
+  // Sim-clock epoch ms when an active repair finishes (v0.39.0, ISS-069) — set with status
+  // 'repairing', cleared by the engine's flip-back pass; NULL = not in repair.
+  repairUntilSimTime: integer('repair_until_sim_time'),
 });
 
 // Cargo packages (v0.12.0) replace the old contracts table end-to-end: a package

lib/deriveEvents.test.ts

@@ -22,6 +22,8 @@ const basePlane = (id: string): PlaneState => ({
   departureSimTime: null,
   lat: 50.03,
   lon: 8.56,
+  health: 100, // v0.39.0 (ISS-069) — full-health fixture default
+  repairUntilSimTime: null,
   queue: [],
 });
 

lib/game/actions.test.ts

@@ -10,12 +10,15 @@ import { haversineKm, initialBearingDeg } from '@/lib/geo';
 import { weatherFor } from '@/lib/weather';
 import { requiredFuelFor, windBurnFactor } from '@/lib/sim/movement';
 import {
+  BROKEN_BURN_MULTIPLIER,
   FUEL_DISCOUNT_PER_REP,
   FUEL_PRICE_PER_L,
   MAX_FUEL_DISCOUNT,
   MAX_PLANE_DISCOUNT,
   PLANE_DISCOUNT_PER_REP,
   PLANE_TYPES,
+  REPAIR_COST,
+  REPAIR_DURATION_MS,
   repRate,
   SELL_FRACTION,
 } from './catalog';
@@ -30,6 +33,7 @@ import {
   loadPackage,
   queueLeg,
   refuelPlane,
+  repairPlane,
   sellPlane,
 } from './actions';
 
@@ -233,6 +237,30 @@ describe('flyPlane', () => {
 
     await expectActionError(flyPlane(inst, 'plane-starter', 'LEMD'), 409, /insufficient fuel/i);
   });
+
+  it('uses the ×1.5 broken burn for fuel feasibility when health is 0 (v0.39.0, ISS-069)', async () => {
+    const inst = await freshDb('fly-broken.db'); // EDDF → LEMD
+    const fc = await loadAirportsGeoJson();
+    const from = fc.features.find((f) => f.properties.icao === HUB_ICAO)!.properties;
+    const to = fc.features.find((f) => f.properties.icao === 'LEMD')!.properties;
+    const km = haversineKm(from.lat, from.lon, to.lat, to.lon);
+    const type = PLANE_TYPES.atr72;
+    const w = weatherFor(HUB_ICAO);
+    const f = windBurnFactor(w.windKt, w.windDirDeg, initialBearingDeg(from.lat, from.lon, to.lat, to.lon));
+    // The tank holds EXACTLY the healthy requirement — a broken plane needs more than that.
+    await inst.db.update(schema.planes)
+      .set({ health: 0, fuel: requiredFuelFor(type.burnPerKm * f, type.emptyWeightKg, type.maxFuel, km) })
+      .where(eq(schema.planes.id, 'plane-starter'));
+
+    await expectActionError(flyPlane(inst, 'plane-starter', 'LEMD'), 409, /insufficient fuel/i);
+
+    // Same tank at full health is flyable — the broken multiplier is what blocked it.
+    const inst2 = await freshDb('fly-broken-healthy.db');
+    await inst2.db.update(schema.planes)
+      .set({ fuel: requiredFuelFor(type.burnPerKm * f, type.emptyWeightKg, type.maxFuel, km) })
+      .where(eq(schema.planes.id, 'plane-starter'));
+    await flyPlane(inst2, 'plane-starter', 'LEMD'); // must not throw
+  });
 });
 
 describe('queueLeg (v0.25.0, ISS-043)', () => {
@@ -779,3 +807,83 @@ describe('refuelPlane', () => {
     );
   });
 });
+
+describe('repairPlane (v0.39.0, ISS-069)', () => {
+  it('charges exactly REPAIR_COST, restores health to 100 and grounds the plane for REPAIR_DURATION_MS', async () => {
+    const inst = await freshDb('repair-ok.db');
+    await inst.db.update(schema.planes).set({ health: 42 }).where(eq(schema.planes.id, 'plane-starter'));
+    const cashBefore = (await inst.db.select().from(schema.account))[0].cash;
+
+    const { cost } = await repairPlane(inst, 'plane-starter');
+
+    expect(cost).toBe(REPAIR_COST);
+    const plane = (await inst.db.select().from(schema.planes))[0];
+    expect(plane.status).toBe('repairing');
+    expect(plane.health).toBe(100); // restored to full…
+    expect(plane.repairUntilSimTime).toBe(T0 + REPAIR_DURATION_MS); // …with the gate set from the seeded clock (no tick in direct calls)
+    const account = (await inst.db.select().from(schema.account))[0];
+    expect(account.cash).toBeCloseTo(cashBefore - REPAIR_COST, 6);
+  });
+
+  it('is a free no-op when health is already full', async () => {
+    const inst = await freshDb('repair-full.db'); // seeded starter at 100
+    const cashBefore = (await inst.db.select().from(schema.account))[0].cash;
+
+    const { cost } = await repairPlane(inst, 'plane-starter');
+
+    expect(cost).toBe(0);
+    const plane = (await inst.db.select().from(schema.planes))[0];
+    expect(plane.status).toBe('available'); // not grounded…
+    expect(plane.health).toBe(100);
+    expect(plane.repairUntilSimTime ?? null).toBeNull(); // …and no gate set
+    expect((await inst.db.select().from(schema.account))[0].cash).toBe(cashBefore);
+  });
+
+  it('rejects a flying plane with 409', async () => {
+    const inst = await freshDb('repair-flying.db');
+    await inst.db.update(schema.planes)
+      .set({ status: 'flying', departureSimTime: T0, destIcao: 'LEMD' })
+      .where(eq(schema.planes.id, 'plane-starter'));
+
+    await expectActionError(repairPlane(inst, 'plane-starter'), 409, /only grounded planes can be repaired/);
+  });
+
+  it('rejects a plane that is already repairing with 409', async () => {
+    const inst = await freshDb('repair-busy.db');
+    await inst.db.update(schema.planes)
+      .set({ status: 'repairing', repairUntilSimTime: T0 + REPAIR_DURATION_MS })
+      .where(eq(schema.planes.id, 'plane-starter'));
+
+    await expectActionError(repairPlane(inst, 'plane-starter'), 409, /only grounded planes can be repaired/);
+  });
+
+  it('blocks load/fly/refuel/sell while repairing (the existing status guards)', async () => {
+    const inst = await freshDb('repair-blocks.db');
+    await inst.db.update(schema.planes).set({ health: 50 }).where(eq(schema.planes.id, 'plane-starter'));
+    await repairPlane(inst, 'plane-starter');
+
+    await insertOpenPackage(inst); // open package at the hub — loadable if the plane were grounded
+    await expectActionError(loadPackage(inst, 'p-open', 'plane-starter'), 409, /repairing/);
+    await expectActionError(flyPlane(inst, 'plane-starter', 'LEMD'), 409, /repairing/);
+    await expectActionError(refuelPlane(inst, 'plane-starter'), 409, /repairing/);
+    // A second plane so the "last remaining" guard cannot fire before the status one.
+    await inst.db.insert(schema.planes).values({
+      id: 'plane-extra', model: 'atr72', status: 'available', fuel: 100, maxFuel: PLANE_TYPES.atr72.maxFuel,
+      locationIcao: HUB_ICAO, destIcao: null, lat: 50, lon: 8, departureSimTime: null,
+    });
+    await expectActionError(sellPlane(inst, 'plane-starter'), 409, /repairing/);
+  });
+
+  it('rejects the repair when cash is below REPAIR_COST with 409', async () => {
+    const inst = await freshDb('repair-poor.db');
+    await inst.db.update(schema.planes).set({ health: 50 }).where(eq(schema.planes.id, 'plane-starter'));
+    await inst.db.update(schema.account).set({ cash: REPAIR_COST - 1 });
+
+    await expectActionError(repairPlane(inst, 'plane-starter'), 409, /insufficient funds/i);
+  });
+
+  it('rejects an unknown id with 404', async () => {
+    const inst = await freshDb('repair-unknown.db');
+    await expectActionError(repairPlane(inst, 'ghost'), 404);
+  });
+});

lib/game/actions.ts

@@ -9,12 +9,15 @@ import { requiredFuelFor, windBurnFactor } from '@/lib/sim/movement';
 import { runAction } from '@/lib/sim/engine';
 import { getStateSnapshot, parseIcaoQueue } from './state';
 import {
+  conditionBurnMultiplier,
   FUEL_DISCOUNT_PER_REP,
   FUEL_PRICE_PER_L,
   MAX_FUEL_DISCOUNT,
   MAX_PLANE_DISCOUNT,
   PLANE_DISCOUNT_PER_REP,
   PLANE_TYPES,
+  REPAIR_COST,
+  REPAIR_DURATION_MS,
   repRate,
   SELL_FRACTION,
 } from './catalog';
@@ -118,8 +121,9 @@ export async function flyPlane(inst: GameDb, planeId: string, destIcao: string):
   const distanceKm = haversineKm(origin.lat, origin.lon, destFeature.properties.lat, destFeature.properties.lon);
   // Weighted burn model (v0.16.0): the leg needs enough fuel to cover it arriving empty; wind-
   // adjusted (v0.36.0) by departure weather vs route heading — every call site uses this same factor.
+  // v0.39.0 (ISS-069): a broken plane (health ≤ 0) burns BROKEN_BURN_MULTIPLIER × more per km.
   const w = weatherFor(plane.locationIcao);
-  const burnPerKm = type.burnPerKm * windBurnFactor(w.windKt, w.windDirDeg, initialBearingDeg(origin.lat, origin.lon, destFeature.properties.lat, destFeature.properties.lon));
+  const burnPerKm = type.burnPerKm * windBurnFactor(w.windKt, w.windDirDeg, initialBearingDeg(origin.lat, origin.lon, destFeature.properties.lat, destFeature.properties.lon)) * conditionBurnMultiplier(plane.health);
   const requiredL = requiredFuelFor(burnPerKm, type.emptyWeightKg, type.maxFuel, distanceKm);
   if (requiredL > plane.fuel) {
     throw new GameActionError(409, `insufficient fuel: the leg needs ${Math.round(requiredL)} L but the plane has ${Math.round(plane.fuel)} L`);
@@ -284,6 +288,7 @@ export async function buyPlane(inst: GameDb, model: string): Promise<{ planeId:
     lat: home.lat,
     lon: home.lon,
     departureSimTime: null,
+    health: 100, // new planes arrive at full health (v0.39.0, ISS-069)
   });
   await inst.db.update(schema.account).set({ cash: Math.round((account.cash - cost) * 100) / 100 });
   await persist(inst);
@@ -367,10 +372,11 @@ export async function refuelPlane(inst: GameDb, planeId: string, opts: RefuelOpt
     const origin = await airportByIcao(plane.locationIcao);
     const dest = await airportByIcao(pkg.destIcao);
     const distanceKm = haversineKm(origin.lat, origin.lon, dest.lat, dest.lon);
-    // Same wind-adjusted requirement flyPlane checks (v0.36.0) — departure weather vs route heading.
+    // Same wind-adjusted requirement flyPlane checks (v0.36.0) — departure weather vs route heading;
+    // v0.39.0 (ISS-069): broken planes burn BROKEN_BURN_MULTIPLIER × more, same factor as flyPlane.
     const w = weatherFor(plane.locationIcao);
     const requiredL = requiredFuelFor(
-      type.burnPerKm * windBurnFactor(w.windKt, w.windDirDeg, initialBearingDeg(origin.lat, origin.lon, dest.lat, dest.lon)),
+      type.burnPerKm * windBurnFactor(w.windKt, w.windDirDeg, initialBearingDeg(origin.lat, origin.lon, dest.lat, dest.lon)) * conditionBurnMultiplier(plane.health),
       type.emptyWeightKg,
       type.maxFuel,
       distanceKm,
@@ -404,6 +410,38 @@ export async function refuelPlane(inst: GameDb, planeId: string, opts: RefuelOpt
   return { cost };
 }
 
+// --- Repair (POST /api/planes/:planeId/repair) — v0.39.0 (ISS-069) ---
+
+// Restore a worn-out plane to full health for the flat REPAIR_COST; it is grounded in 'repairing'
+// status until sim.clockMs + REPAIR_DURATION_MS, when the engine's tick flips it back to
+// 'available'. Only GROUNDED planes can be repaired (409 otherwise); an already-full-health
+// repair is a free no-op (mirrors refuel's). 404 unknown plane; 409 not grounded / insufficient funds.
+export async function repairPlane(inst: GameDb, planeId: string): Promise<{ cost: number }> {
+  const rows = await inst.db.select().from(schema.planes).where(eq(schema.planes.id, planeId));
+  const plane = rows[0];
+  if (!plane) throw new GameActionError(404, `plane ${planeId} not found`);
+  if (plane.status !== 'available') {
+    throw new GameActionError(409, `plane is ${plane.status}, only grounded planes can be repaired`);
+  }
+  // Free no-op when the plane is already at full health — nothing to repair.
+  if (plane.health >= 100) return { cost: 0 };
+
+  const sim = (await inst.db.select().from(schema.simState))[0];
+  if (!sim) throw new Error('sim_state row missing');
+  const account = (await inst.db.select().from(schema.account))[0];
+  if (!account) throw new Error('account row missing');
+  if (account.cash < REPAIR_COST) {
+    throw new GameActionError(409, `insufficient funds: repair costs ${REPAIR_COST}, you have ${Math.round(account.cash)}`);
+  }
+
+  await inst.db.update(schema.planes)
+    .set({ health: 100, status: 'repairing', repairUntilSimTime: sim.clockMs + REPAIR_DURATION_MS })
+    .where(eq(schema.planes.id, planeId));
+  await inst.db.update(schema.account).set({ cash: Math.round((account.cash - REPAIR_COST) * 100) / 100 });
+  await persist(inst);
+  return { cost: REPAIR_COST };
+}
+
 // --- Route helper (response convention, v0.8.0) ---
 
 // Run an action under the sim lock — tick FIRST so validation/mutation see current

lib/game/catalog.test.ts

@@ -1,5 +1,5 @@
 import { describe, expect, it } from 'vitest';
-import { FUEL_DISCOUNT_PER_REP, MAX_FUEL_DISCOUNT, MAX_PLANE_DISCOUNT, PLANE_DISCOUNT_PER_REP, PLANE_TYPES, repRate, STARTER_MODEL } from './catalog';
+import { BROKEN_BURN_MULTIPLIER, conditionBurnMultiplier, FUEL_DISCOUNT_PER_REP, MAX_FUEL_DISCOUNT, MAX_PLANE_DISCOUNT, PLANE_DISCOUNT_PER_REP, PLANE_TYPES, repRate, STARTER_MODEL } from './catalog';
 import { STARTING_REPUTATION } from './seed';
 
 // v0.28.0 (ISS-047) — catalog sanity: the progression ladder must stay well-formed as types are added.
@@ -43,3 +43,21 @@ describe('repRate', () => {
     expect(repRate(1_000_000, FUEL_DISCOUNT_PER_REP, MAX_FUEL_DISCOUNT)).toBe(MAX_FUEL_DISCOUNT);
   });
 });
+
+// v0.39.0 (ISS-069) — the broken-state burn factor: ×BROKEN_BURN_MULTIPLIER at/below zero health, exactly 1 above it.
+describe('conditionBurnMultiplier', () => {
+  it('is exactly 1 for any positive health', () => {
+    expect(conditionBurnMultiplier(100)).toBe(1);
+    expect(conditionBurnMultiplier(42)).toBe(1);
+    expect(conditionBurnMultiplier(0.5)).toBe(1); // worn but not broken
+  });
+
+  it('is exactly BROKEN_BURN_MULTIPLIER at and below zero health', () => {
+    expect(conditionBurnMultiplier(0)).toBe(BROKEN_BURN_MULTIPLIER);
+    expect(conditionBurnMultiplier(-3)).toBe(BROKEN_BURN_MULTIPLIER); // defensive — wear clamps at 0, but the gate is <= 0
+  });
+
+  it('pins the broken multiplier at ×1.5', () => {
+    expect(BROKEN_BURN_MULTIPLIER).toBe(1.5);
+  });
+});

lib/game/catalog.ts

@@ -122,6 +122,25 @@ export const FUEL_DISCOUNT_PER_REP = 0.005;
 // ponytail: balance-tunable — max refuel price discount (reached at rep ≥ 50).
 export const MAX_FUEL_DISCOUNT = 0.2;
 
+// --- Maintenance (v0.39.0, ISS-069) ---
+
+// ponytail: balance-tunable — health lost per km of landed legs (~13 mid-range EDDF↔LEMD hops to break from full).
+export const WEAR_PER_KM = 0.005;
+
+// ponytail: balance-tunable — burn multiplier for a broken plane (health ≤ 0): it still flies, just thirsty.
+export const BROKEN_BURN_MULTIPLIER = 1.5;
+
+// Broken-state burn factor for one plane's health — the third multiplicative term alongside wind at every
+// per-plane burn site (flyPlane feasibility, refuel forFlight, engine landed fuel + auto-chain, live display).
+export function conditionBurnMultiplier(health: number): number {
+  return health <= 0 ? BROKEN_BURN_MULTIPLIER : 1;
+}
+
+// ponytail: balance-tunable — flat repair cost in € (per-type if balance demands it).
+export const REPAIR_COST = 1_500;
+// ponytail: balance-tunable — how long a repair grounds the plane, sim ms (3 game days).
+export const REPAIR_DURATION_MS = 3 * 86_400_000;
+
 // Snapshot shape of one catalog entry in GET /api/state (v0.10.0): `model` is the
 // id used by buy/dispatch, `label` the display name — clients compute all market
 // previews (buy price, sell payout, refuel cost) from these + the economy constants.

lib/game/seed.test.ts

@@ -49,6 +49,7 @@ describe('buildSeed', () => {
       lat: 50.0333,
       lon: 8.5706,
       queue: [], // v0.25.0 (ISS-043) — no queued legs on first run
+      health: 100, // v0.39.0 (ISS-069) — full health on first run
     });
   });
 

lib/game/seed.ts

@@ -42,6 +42,8 @@ export interface SeedPlane {
   // Upcoming legs not yet started (v0.25.0, ISS-043) — serialized to the queue
   // column as JSON text on insert; defaults to an empty queue.
   queue?: string[];
+  // Structural health in [0, 100] (v0.39.0, ISS-069) — new planes start at full health.
+  health: number;
 }
 
 export interface SeedPackage {
@@ -237,6 +239,7 @@ export function buildSeed(input: {
     lat: hub.lat,
     lon: hub.lon,
     queue: [], // no queued legs on first run (v0.25.0)
+    health: 100, // full health on first run (v0.39.0, ISS-069)
   };
 
   const count = PACKAGE_COUNT_MIN + Math.floor(rng() * (PACKAGE_COUNT_MAX - PACKAGE_COUNT_MIN + 1));

lib/game/state.ts

@@ -3,7 +3,7 @@ import { haversineKm, initialBearingDeg } from '@/lib/geo';
 import { weatherFor } from '@/lib/weather';
 import { getGameDb } from '@/lib/db/client';
 import * as schema from '@/lib/db/schema';
-import { catalogEntries, FUEL_PRICE_PER_L, PLANE_TYPES, SELL_FRACTION, type CatalogEntry } from './catalog';
+import { conditionBurnMultiplier, catalogEntries, FUEL_PRICE_PER_L, PLANE_TYPES, SELL_FRACTION, type CatalogEntry } from './catalog';
 import { fuelAtWeighted, progressAt, positionAt, windBurnFactor } from '@/lib/sim/movement';
 
 // Read-only game-state snapshot for client polling (GET /api/state).
@@ -11,7 +11,8 @@ import { fuelAtWeighted, progressAt, positionAt, windBurnFactor } from '@/lib/si
 export interface PlaneState {
   id: string;
   model: string;
-  status: 'available' | 'flying';
+  // v0.39.0 (ISS-069): 'repairing' = grounded in the shop until repairUntilSimTime passes.
+  status: 'available' | 'flying' | 'repairing';
   fuel: number;
   maxFuel: number;
   locationIcao: string;
@@ -28,6 +29,11 @@ export interface PlaneState {
   // Upcoming legs NOT yet started (v0.25.0, ISS-043) — ordered ICAOs; the active
   // leg is destIcao. The engine auto-chains queue[0] on landing when fuel covers it.
   queue: string[];
+  // Structural health in [0, 100] (v0.39.0, ISS-069) — wears down with distance flown; at 0 the
+  // plane is broken and burns BROKEN_BURN_MULTIPLIER × more fuel until repaired.
+  health: number;
+  // Sim-clock epoch ms when an active repair finishes (v0.39.0, ISS-069); null when not in repair.
+  repairUntilSimTime: number | null;
 }
 
 // Parse the planes.queue JSON column into an ICAO list (v0.25.0). Guards against
@@ -107,10 +113,12 @@ export async function getStateSnapshot(): Promise<StateSnapshot> {
     const pos = positionAt(from.lat, from.lon, to.lat, to.lon, progress);
     // Wind-adjusted burn (v0.36.0) — weather is a pure function of the departure ICAO, so this
     // recomputes exactly the factor the engine used for the leg; no stored state needed.
+    // v0.39.0 (ISS-069): broken planes burn BROKEN_BURN_MULTIPLIER × more — p.health is frozen at
+    // departure (wear lands only), so this stays bit-consistent with the engine's landed fuel.
     const w = weatherFor(p.locationIcao);
     return { ...pos, fuel: fuelAtWeighted(
       p.fuel,
-      type.burnPerKm * windBurnFactor(w.windKt, w.windDirDeg, initialBearingDeg(from.lat, from.lon, to.lat, to.lon)),
+      type.burnPerKm * windBurnFactor(w.windKt, w.windDirDeg, initialBearingDeg(from.lat, from.lon, to.lat, to.lon)) * conditionBurnMultiplier(p.health),
       type.emptyWeightKg,
       type.maxFuel,
       distanceKm,
@@ -140,6 +148,8 @@ export async function getStateSnapshot(): Promise<StateSnapshot> {
         lat: live?.lat ?? p.lat,
         lon: live?.lon ?? p.lon,
         queue: parseIcaoQueue(p.queue),
+        health: p.health, // v0.39.0 (ISS-069) — stored value; wear accumulates at landing only
+        repairUntilSimTime: p.repairUntilSimTime,
       };
     }),
     packages: packageRows.map((p) => ({

lib/mapData.test.ts

@@ -34,8 +34,8 @@ describe('planesGeoJson', () => {
     const fc = planesGeoJson(
       snapshot({
         planes: [
-          { id: 'plane-starter', model: 'atr72', status: 'available', fuel: 6300, maxFuel: 6300, locationIcao: 'EDDF', locationName: 'Frankfurt Main Airport', destIcao: null, destName: null, departureSimTime: null, lat: 50.03, lon: 8.56, queue: [] },
-          { id: 'plane-2', model: 'atr72', status: 'flying', fuel: 4000, maxFuel: 6300, locationIcao: 'EDDF', locationName: 'Frankfurt Main Airport', destIcao: 'EDDV', destName: 'Hannover Airport', departureSimTime: 1000, lat: 51.2, lon: 9.1, queue: [] },
+          { id: 'plane-starter', model: 'atr72', status: 'available', fuel: 6300, maxFuel: 6300, locationIcao: 'EDDF', locationName: 'Frankfurt Main Airport', destIcao: null, destName: null, departureSimTime: null, lat: 50.03, lon: 8.56, health: 100, repairUntilSimTime: null, queue: [] },
+          { id: 'plane-2', model: 'atr72', status: 'flying', fuel: 4000, maxFuel: 6300, locationIcao: 'EDDF', locationName: 'Frankfurt Main Airport', destIcao: 'EDDV', destName: 'Hannover Airport', departureSimTime: 1000, lat: 51.2, lon: 9.1, health: 100, repairUntilSimTime: null, queue: [] },
         ],
       }),
     );
@@ -61,7 +61,7 @@ describe('planesGeoJson', () => {
       snapshot({
         catalog: [],
         planes: [
-          { id: 'p1', model: 'mystery', status: 'available', fuel: 1, maxFuel: 2, locationIcao: 'EDDF', locationName: 'x', destIcao: null, destName: null, departureSimTime: null, lat: 0, lon: 0, queue: [] },
+          { id: 'p1', model: 'mystery', status: 'available', fuel: 1, maxFuel: 2, locationIcao: 'EDDF', locationName: 'x', destIcao: null, destName: null, departureSimTime: null, lat: 0, lon: 0, health: 100, repairUntilSimTime: null, queue: [] },
         ],
       }),
     );
@@ -72,7 +72,7 @@ describe('planesGeoJson', () => {
     const fc = planesGeoJson(
       snapshot({
         planes: [
-          { id: 'p1', model: 'atr72', status: 'flying', fuel: 1, maxFuel: 2, locationIcao: 'EDDF', locationName: 'x', destIcao: null, destName: null, departureSimTime: 0, lat: 0, lon: 0, queue: [] },
+          { id: 'p1', model: 'atr72', status: 'flying', fuel: 1, maxFuel: 2, locationIcao: 'EDDF', locationName: 'x', destIcao: null, destName: null, departureSimTime: 0, lat: 0, lon: 0, health: 100, repairUntilSimTime: null, queue: [] },
         ],
       }),
     );
@@ -89,7 +89,7 @@ describe('routesGeoJson (v0.12.0 — one line per flying plane\'s current leg)',
     const fc = routesGeoJson(
       snapshot({
         planes: [
-          { id: 'p1', model: 'atr72', status: 'available', fuel: 1, maxFuel: 2, locationIcao: 'EDDF', locationName: 'F', destIcao: null, destName: null, departureSimTime: null, lat: 50.03, lon: 8.56, queue: [] },
+          { id: 'p1', model: 'atr72', status: 'available', fuel: 1, maxFuel: 2, locationIcao: 'EDDF', locationName: 'F', destIcao: null, destName: null, departureSimTime: null, lat: 50.03, lon: 8.56, health: 100, repairUntilSimTime: null, queue: [] },
         ],
       }),
       AIRPORTS,
@@ -101,7 +101,7 @@ describe('routesGeoJson (v0.12.0 — one line per flying plane\'s current leg)',
     const fc = routesGeoJson(
       snapshot({
         planes: [
-          { id: 'p1', model: 'atr72', status: 'flying', fuel: 1, maxFuel: 2, locationIcao: 'EDDF', locationName: 'F', destIcao: 'EHAM', destName: 'A', departureSimTime: 0, lat: 51, lon: 9, queue: [] },
+          { id: 'p1', model: 'atr72', status: 'flying', fuel: 1, maxFuel: 2, locationIcao: 'EDDF', locationName: 'F', destIcao: 'EHAM', destName: 'A', departureSimTime: 0, lat: 51, lon: 9, health: 100, repairUntilSimTime: null, queue: [] },
         ],
       }),
       AIRPORTS,
@@ -118,7 +118,7 @@ describe('routesGeoJson (v0.12.0 — one line per flying plane\'s current leg)',
     const fc = routesGeoJson(
       snapshot({
         planes: [
-          { id: 'p1', model: 'atr72', status: 'flying', fuel: 1, maxFuel: 2, locationIcao: 'ZZZZ', locationName: '?', destIcao: 'EDDV', destName: 'H', departureSimTime: 0, lat: 0, lon: 0, queue: [] },
+          { id: 'p1', model: 'atr72', status: 'flying', fuel: 1, maxFuel: 2, locationIcao: 'ZZZZ', locationName: '?', destIcao: 'EDDV', destName: 'H', departureSimTime: 0, lat: 0, lon: 0, health: 100, repairUntilSimTime: null, queue: [] },
         ],
       }),
       AIRPORTS,
@@ -130,8 +130,8 @@ describe('routesGeoJson (v0.12.0 — one line per flying plane\'s current leg)',
     const fc = routesGeoJson(
       snapshot({
         planes: [
-          { id: 'p1', model: 'atr72', status: 'flying', fuel: 1, maxFuel: 2, locationIcao: 'EDDF', locationName: 'F', destIcao: 'EDDV', destName: 'H', departureSimTime: 0, lat: 51, lon: 9, queue: [] },
-          { id: 'p2', model: 'atr72', status: 'flying', fuel: 1, maxFuel: 2, locationIcao: 'EDDV', locationName: 'H', destIcao: 'EHAM', destName: 'A', departureSimTime: 0, lat: 52.4, lon: 9.6, queue: [] },
+          { id: 'p1', model: 'atr72', status: 'flying', fuel: 1, maxFuel: 2, locationIcao: 'EDDF', locationName: 'F', destIcao: 'EDDV', destName: 'H', departureSimTime: 0, lat: 51, lon: 9, health: 100, repairUntilSimTime: null, queue: [] },
+          { id: 'p2', model: 'atr72', status: 'flying', fuel: 1, maxFuel: 2, locationIcao: 'EDDV', locationName: 'H', destIcao: 'EHAM', destName: 'A', departureSimTime: 0, lat: 52.4, lon: 9.6, health: 100, repairUntilSimTime: null, queue: [] },
         ],
       }),
       AIRPORTS,
@@ -144,7 +144,7 @@ describe('queuedRoutesGeoJson (ISS-043 v0.26.0 — dotted queue line: dest → q
   it('draws nothing for a grounded plane, even with a non-empty queue', () => {
     const fc = queuedRoutesGeoJson(
       [
-        { id: 'p1', model: 'atr72', status: 'available', fuel: 1, maxFuel: 2, locationIcao: 'EDDF', locationName: 'F', destIcao: null, destName: null, departureSimTime: null, lat: 50.03, lon: 8.56, queue: ['EHAM'] },
+        { id: 'p1', model: 'atr72', status: 'available', fuel: 1, maxFuel: 2, locationIcao: 'EDDF', locationName: 'F', destIcao: null, destName: null, departureSimTime: null, lat: 50.03, lon: 8.56, health: 100, repairUntilSimTime: null, queue: ['EHAM'] },
       ],
       AIRPORTS,
     );
@@ -154,7 +154,7 @@ describe('queuedRoutesGeoJson (ISS-043 v0.26.0 — dotted queue line: dest → q
   it('draws nothing for a flying plane with an empty queue', () => {
     const fc = queuedRoutesGeoJson(
       [
-        { id: 'p1', model: 'atr72', status: 'flying', fuel: 1, maxFuel: 2, locationIcao: 'EDDF', locationName: 'F', destIcao: 'EHAM', destName: 'A', departureSimTime: 0, lat: 51, lon: 9, queue: [] },
+        { id: 'p1', model: 'atr72', status: 'flying', fuel: 1, maxFuel: 2, locationIcao: 'EDDF', locationName: 'F', destIcao: 'EHAM', destName: 'A', departureSimTime: 0, lat: 51, lon: 9, health: 100, repairUntilSimTime: null, queue: [] },
       ],
       AIRPORTS,
     );
@@ -165,7 +165,7 @@ describe('queuedRoutesGeoJson (ISS-043 v0.26.0 — dotted queue line: dest → q
     const fc = queuedRoutesGeoJson(
       [
         // Active leg EDDF→EHAM stays in routesGeoJson; the queue line is ONLY EHAM → EDDV → LEMD.
-        { id: 'p1', model: 'atr72', status: 'flying', fuel: 1, maxFuel: 2, locationIcao: 'EDDF', locationName: 'F', destIcao: 'EHAM', destName: 'A', departureSimTime: 0, lat: 51, lon: 9, queue: ['EDDV', 'LEMD'] },
+        { id: 'p1', model: 'atr72', status: 'flying', fuel: 1, maxFuel: 2, locationIcao: 'EDDF', locationName: 'F', destIcao: 'EHAM', destName: 'A', departureSimTime: 0, lat: 51, lon: 9, health: 100, repairUntilSimTime: null, queue: ['EDDV', 'LEMD'] },
       ],
       AIRPORTS,
     );
@@ -182,8 +182,8 @@ describe('queuedRoutesGeoJson (ISS-043 v0.26.0 — dotted queue line: dest → q
   it('skips a plane whose dest or a queued ICAO is missing from the airport index', () => {
     const fc = queuedRoutesGeoJson(
       [
-        { id: 'p1', model: 'atr72', status: 'flying', fuel: 1, maxFuel: 2, locationIcao: 'EDDF', locationName: 'F', destIcao: 'ZZZZ', destName: '?', departureSimTime: 0, lat: 51, lon: 9, queue: ['EHAM'] },
-        { id: 'p2', model: 'atr72', status: 'flying', fuel: 1, maxFuel: 2, locationIcao: 'EDDF', locationName: 'F', destIcao: 'EHAM', destName: 'A', departureSimTime: 0, lat: 51, lon: 9, queue: ['ZZZZ'] },
+        { id: 'p1', model: 'atr72', status: 'flying', fuel: 1, maxFuel: 2, locationIcao: 'EDDF', locationName: 'F', destIcao: 'ZZZZ', destName: '?', departureSimTime: 0, lat: 51, lon: 9, health: 100, repairUntilSimTime: null, queue: ['EHAM'] },
+        { id: 'p2', model: 'atr72', status: 'flying', fuel: 1, maxFuel: 2, locationIcao: 'EDDF', locationName: 'F', destIcao: 'EHAM', destName: 'A', departureSimTime: 0, lat: 51, lon: 9, health: 100, repairUntilSimTime: null, queue: ['ZZZZ'] },
       ],
       AIRPORTS,
     );
@@ -193,9 +193,9 @@ describe('queuedRoutesGeoJson (ISS-043 v0.26.0 — dotted queue line: dest → q
   it('one feature per qualifying plane — grounded and empty-queue planes draw nothing', () => {
     const fc = queuedRoutesGeoJson(
       [
-        { id: 'p1', model: 'atr72', status: 'flying', fuel: 1, maxFuel: 2, locationIcao: 'EDDF', locationName: 'F', destIcao: 'EHAM', destName: 'A', departureSimTime: 0, lat: 51, lon: 9, queue: ['LEMD'] },
-        { id: 'p2', model: 'atr72', status: 'flying', fuel: 1, maxFuel: 2, locationIcao: 'EHAM', locationName: 'A', destIcao: 'EDDV', destName: 'H', departureSimTime: 0, lat: 52.3, lon: 4.7, queue: [] },
-        { id: 'p3', model: 'atr72', status: 'available', fuel: 1, maxFuel: 2, locationIcao: 'EDDV', locationName: 'H', destIcao: null, destName: null, departureSimTime: null, lat: 52.46, lon: 9.68, queue: ['LEMD'] },
+        { id: 'p1', model: 'atr72', status: 'flying', fuel: 1, maxFuel: 2, locationIcao: 'EDDF', locationName: 'F', destIcao: 'EHAM', destName: 'A', departureSimTime: 0, lat: 51, lon: 9, health: 100, repairUntilSimTime: null, queue: ['LEMD'] },
+        { id: 'p2', model: 'atr72', status: 'flying', fuel: 1, maxFuel: 2, locationIcao: 'EHAM', locationName: 'A', destIcao: 'EDDV', destName: 'H', departureSimTime: 0, lat: 52.3, lon: 4.7, health: 100, repairUntilSimTime: null, queue: [] },
+        { id: 'p3', model: 'atr72', status: 'available', fuel: 1, maxFuel: 2, locationIcao: 'EDDV', locationName: 'H', destIcao: null, destName: null, departureSimTime: null, lat: 52.46, lon: 9.68, health: 100, repairUntilSimTime: null, queue: ['LEMD'] },
       ],
       AIRPORTS,
     );

lib/mapData.ts

@@ -10,7 +10,8 @@ import { positionAt } from './sim/movement';
 export interface PlaneFeatureProps {
   id: string;
   modelLabel: string;
-  status: 'available' | 'flying';
+  // v0.39.0 (ISS-069): 'repairing' planes render on the grounded layer (flying === false).
+  status: 'available' | 'flying' | 'repairing';
   fuelText: string; // "1234 / 6300 L"
   routeText: string; // "Origin → Destination" while flying, '' when grounded
   flying: boolean;

lib/openapi.test.ts

@@ -3,7 +3,7 @@ import { describe, expect, it } from 'vitest';
 import { openApiSpec } from './openapi';
 
 describe('OpenAPI spec', () => {
-  it('documents exactly the thirteen public endpoints (4 read + 9 player actions)', () => {
+  it('documents exactly the fourteen public endpoints (4 read + 10 player actions)', () => {
     expect(Object.keys(openApiSpec.paths).sort()).toEqual([
       '/api/airports',
       '/api/market/buy-plane',
@@ -15,6 +15,7 @@ describe('OpenAPI spec', () => {
       '/api/planes/{planeId}/queue', // v0.25.0 (ISS-043)
       '/api/planes/{planeId}/queue/cancel', // v0.25.0 (ISS-043)
       '/api/planes/{planeId}/refuel',
+      '/api/planes/{planeId}/repair', // v0.39.0 (ISS-069)
       '/api/sim',
       '/api/state',
       '/api/version',
@@ -115,6 +116,7 @@ describe('OpenAPI spec', () => {
       'destIcao',
       'destName',
       'fuel',
+      'health', // v0.39.0 (ISS-069) — structural health in [0, 100]
       'id',
       'lat',
       'locationIcao',
@@ -123,6 +125,7 @@ describe('OpenAPI spec', () => {
       'maxFuel',
       'model',
       'queue', // v0.25.0 (ISS-043) — upcoming legs not yet started
+      'repairUntilSimTime', // v0.39.0 (ISS-069) — active repair gate; null when not repairing
       'status',
     ]);
 
@@ -174,7 +177,7 @@ describe('OpenAPI spec', () => {
     expect(Object.keys(error)).toEqual(['error']);
   });
 
-  it('documents the eight action endpoints: snapshot on 200, Error on their 4xx paths', () => {
+  it('documents the nine action endpoints: snapshot on 200, Error on their 4xx paths', () => {
     // The spec object is a literal type; these helpers view it as plain JSON.
     const post = (p: string) =>
       ((openApiSpec.paths as Record<string, { post?: unknown }>)[p]?.post ?? {}) as {
@@ -193,6 +196,7 @@ describe('OpenAPI spec', () => {
       '/api/market/buy-plane',
       '/api/market/sell-plane',
       '/api/planes/{planeId}/refuel',
+      '/api/planes/{planeId}/repair', // v0.39.0 (ISS-069)
     ]) {
       const ok = post(p).responses['200'] as { content: Record<string, { schema: { $ref: string } }> };
       expect(ok.content['application/json'].schema.$ref).toBe('#/components/schemas/StateSnapshot');
@@ -208,6 +212,7 @@ describe('OpenAPI spec', () => {
     expect(errorCodes('/api/market/buy-plane')).toEqual(['400', '409']);
     expect(errorCodes('/api/market/sell-plane')).toEqual(['400', '404', '409']);
     expect(errorCodes('/api/planes/{planeId}/refuel')).toEqual(['400', '404', '409']); // v0.16.0 optional body
+    expect(errorCodes('/api/planes/{planeId}/repair')).toEqual(['404', '409']); // v0.39.0 (ISS-069) — no body, so no 400
 
     // Request bodies: load/fly/buy/sell take their dedicated schemas; abandon takes none;
     // refuel's is OPTIONAL (v0.16.0) — no body still means "fill to full".
@@ -233,6 +238,7 @@ describe('OpenAPI spec', () => {
     const refuelBody = post('/api/planes/{planeId}/refuel').requestBody;
     expect(refuelBody?.content['application/json'].schema.$ref).toBe('#/components/schemas/RefuelRequest');
     expect(refuelBody?.required).toBe(false); // optional — no body still means "fill to full"
+    expect(post('/api/planes/{planeId}/repair').requestBody).toBeUndefined(); // v0.39.0 (ISS-069) — no body, like abandon
 
     // Path parameters are declared on the parameterized routes.
     const paramNames = (p: string) => post(p).parameters?.map((x) => x.name);
@@ -242,6 +248,7 @@ describe('OpenAPI spec', () => {
     expect(paramNames('/api/planes/{planeId}/queue')).toEqual(['planeId']); // v0.25.0 (ISS-043)
     expect(paramNames('/api/planes/{planeId}/queue/cancel')).toEqual(['planeId']); // v0.25.0 (ISS-043)
     expect(paramNames('/api/planes/{planeId}/refuel')).toEqual(['planeId']);
+    expect(paramNames('/api/planes/{planeId}/repair')).toEqual(['planeId']); // v0.39.0 (ISS-069)
 
     // Request schema shapes.
     const load = openApiSpec.components.schemas.LoadPackageRequest;

lib/openapi.ts

@@ -404,6 +404,31 @@ export const openApiSpec = {
         },
       },
     },
+    '/api/planes/{planeId}/repair': {
+      post: {
+        summary: 'Repair a grounded plane',
+        description:
+          'Restore a worn-out plane to full health for the flat repair cost (v0.39.0, ISS-069): the plane is grounded in "repairing" status until 3 sim days pass, when the engine\'s tick flips it back to "available". While repairing it cannot load, fly, refuel or be sold; a broken plane (health ≤ 0) still flies but burns 50% more fuel. A full-health repair is a free no-op (cost 0). No body.',
+        operationId: 'repairPlane',
+        parameters: [
+          { name: 'planeId', in: 'path', required: true, schema: { type: 'string' } },
+        ],
+        responses: {
+          200: {
+            description: 'Repair started (or free no-op) — full state snapshot (health 100, status "repairing" with the gate set, cash reduced by the flat cost)',
+            content: { 'application/json': { schema: { $ref: '#/components/schemas/StateSnapshot' } } },
+          },
+          404: {
+            description: 'Unknown plane id',
+            content: { 'application/json': { schema: { $ref: '#/components/schemas/Error' } } },
+          },
+          409: {
+            description: 'Plane is not grounded (flying or already repairing), or cash is insufficient for the repair cost',
+            content: { 'application/json': { schema: { $ref: '#/components/schemas/Error' } } },
+          },
+        },
+      },
+    },
   },
   components: {
     schemas: {
@@ -595,7 +620,7 @@ export const openApiSpec = {
         properties: {
           id: { type: 'string' },
           model: { type: 'string' },
-          status: { enum: ['available', 'flying'] },
+          status: { enum: ['available', 'flying', 'repairing'] }, // v0.39.0 (ISS-069) — "repairing" = grounded in the shop until repairUntilSimTime passes
           fuel: { type: 'number' },
           maxFuel: { type: 'number' },
           locationIcao: { type: 'string' },
@@ -620,6 +645,16 @@ export const openApiSpec = {
             description:
               'Upcoming flight legs NOT yet started (v0.25.0) — ordered ICAOs; the active leg is destIcao. The engine auto-chains queue[0] on landing when fuel covers it.',
           },
+          health: {
+            type: 'number',
+            description:
+              'Structural health in [0, 100] (v0.39.0) — wears down by a fixed amount per km of landed legs; at 0 the plane is broken and burns 50% more fuel until repaired.',
+          },
+          repairUntilSimTime: {
+            type: ['integer', 'null'],
+            description:
+              'Sim-clock epoch ms when an active repair finishes (v0.39.0) — set with status "repairing", cleared by the engine\'s flip-back; null when not in repair.',
+          },
         },
         required: [
           'id',
@@ -635,6 +670,8 @@ export const openApiSpec = {
           'lat',
           'lon',
           'queue',
+          'health', // v0.39.0 (ISS-069) — structural health in [0, 100]
+          'repairUntilSimTime', // v0.39.0 (ISS-069) — active repair gate; null when not repairing
         ],
       },
       PackageState: {

lib/sim/engine.test.ts

@@ -8,7 +8,7 @@ import * as schema from '@/lib/db/schema';
 import { loadAirportsGeoJson } from '@/lib/airports';
 import { haversineKm, initialBearingDeg } from '@/lib/geo';
 import { weatherFor } from '@/lib/weather';
-import { PLANE_TYPES } from '@/lib/game/catalog';
+import { BROKEN_BURN_MULTIPLIER, PLANE_TYPES, WEAR_PER_KM } from '@/lib/game/catalog';
 import { SPECIALS } from '@/lib/game/specials';
 import { MARKET_TARGET_OPEN_PACKAGES, mulberry32 } from '@/lib/game/seed';
 import { arrivalTimeFor, fuelAtWeighted, requiredFuelFor, windBurnFactor } from './movement';
@@ -16,6 +16,7 @@ import {
   clampTimeScale,
   deliverPackages,
   expirePackages,
+  finishRepairs,
   MAX_TICK_ELAPSED_MS,
   MAX_TIME_SCALE,
   MIN_TIME_SCALE,
@@ -331,6 +332,114 @@ describe('deliverPackages (v0.12.0 arrival delivery)', () => {
   });
 });
 
+describe('wear on landed legs + broken burn (v0.39.0, ISS-069)', () => {
+  const FROM = 'EDDF';
+  const TO = 'LEMD';
+
+  // Starter flying EDDF→LEMD with a full tank — same shape as the deliverPackages setup above.
+  async function setupFlight(name: string) {
+    const inst = await freshDb(name);
+    const fc = await loadAirportsGeoJson();
+    const from = fc.features.find((f) => f.properties.icao === FROM)!.properties;
+    const to = fc.features.find((f) => f.properties.icao === TO)!.properties;
+    const km = haversineKm(from.lat, from.lon, to.lat, to.lon);
+    const type = PLANE_TYPES.atr72;
+
+    await inst.db.update(schema.planes)
+      .set({ status: 'flying', destIcao: TO, departureSimTime: T0, fuel: type.maxFuel })
+      .where(eq(schema.planes.id, 'plane-starter'));
+
+    return { inst, from, to, km, type };
+  }
+
+  it('drops health by exactly WEAR_PER_KM × km on a landed leg', async () => {
+    const { inst, km } = await setupFlight('wear-leg.db');
+
+    expect(await deliverPackages(inst, T0 + travelMs(km, PLANE_TYPES.atr72.speedKmh))).toBe(1);
+
+    const plane = (await inst.db.select().from(schema.planes))[0];
+    expect(plane.health).toBeCloseTo(100 - WEAR_PER_KM * km, 9); // one mid-range hop ≈ −9.8 health
+  });
+
+  it('clamps at 0 across multiple legs', async () => {
+    const { inst, from, to, km, type } = await setupFlight('wear-clamp.db');
+    // Start below one leg's wear so the first landing clamps…
+    await inst.db.update(schema.planes)
+      .set({ health: WEAR_PER_KM * km / 2 })
+      .where(eq(schema.planes.id, 'plane-starter'));
+
+    expect(await deliverPackages(inst, T0 + travelMs(km, type.speedKmh))).toBe(1);
+    let plane = (await inst.db.select().from(schema.planes))[0];
+    expect(plane.health).toBe(0); // clamped — never negative…
+
+    // …and a second leg keeps it pinned at 0.
+    const eham = (await loadAirportsGeoJson()).features.find((f) => f.properties.icao === 'EHAM')!.properties;
+    const nextKm = haversineKm(to.lat, to.lon, eham.lat, eham.lon);
+    await inst.db.update(schema.planes)
+      .set({ status: 'flying', destIcao: 'EHAM', departureSimTime: T0 + travelMs(km, type.speedKmh), fuel: type.maxFuel })
+      .where(eq(schema.planes.id, 'plane-starter'));
+
+    expect(await deliverPackages(inst, T0 + travelMs(km, type.speedKmh) + travelMs(nextKm, type.speedKmh))).toBe(1);
+    plane = (await inst.db.select().from(schema.planes))[0];
+    expect(plane.health).toBe(0); // still clamped after the second leg
+  });
+
+  it('a broken plane burns ×1.5 more fuel on the leg (landed fuel)', async () => {
+    const { inst, from, to, km, type } = await setupFlight('wear-broken.db');
+    await inst.db.update(schema.planes).set({ health: 0 }).where(eq(schema.planes.id, 'plane-starter'));
+
+    expect(await deliverPackages(inst, T0 + travelMs(km, type.speedKmh))).toBe(1);
+
+    const w = weatherFor(FROM);
+    const f = windBurnFactor(w.windKt, w.windDirDeg, initialBearingDeg(from.lat, from.lon, to.lat, to.lon));
+    const plane = (await inst.db.select().from(schema.planes))[0];
+    // The ×1.5-adjusted closed form — the same factor livePlane() shows in flight…
+    expect(plane.fuel).toBeCloseTo(
+      fuelAtWeighted(type.maxFuel, type.burnPerKm * f * BROKEN_BURN_MULTIPLIER, type.emptyWeightKg, type.maxFuel, km, 1),
+      6,
+    );
+
+    // …and strictly less than the healthy control on the identical leg.
+    const control = await setupFlight('wear-broken-control.db');
+    expect(await deliverPackages(control.inst, T0 + travelMs(km, type.speedKmh))).toBe(1);
+    const healthy = (await control.inst.db.select().from(schema.planes))[0];
+    expect(healthy.fuel).toBeCloseTo(fuelAtWeighted(type.maxFuel, type.burnPerKm * f, type.emptyWeightKg, type.maxFuel, km, 1), 6);
+    expect(plane.fuel).toBeLessThan(healthy.fuel); // the broken plane genuinely burned more
+  });
+});
+
+describe('finishRepairs (v0.39.0, ISS-069)', () => {
+  it('flips repairing planes back to available once the gate passes, clearing the gate', async () => {
+    const inst = await freshDb('repair-finish.db');
+    await inst.db.update(schema.planes)
+      .set({ status: 'repairing', repairUntilSimTime: T0 + 5_000 })
+      .where(eq(schema.planes.id, 'plane-starter'));
+
+    expect(await finishRepairs(inst, T0 + 4_999)).toBe(0); // gate not reached yet…
+    let plane = (await inst.db.select().from(schema.planes))[0];
+    expect(plane.status).toBe('repairing');
+
+    expect(await finishRepairs(inst, T0 + 5_000)).toBe(1); // <= is inclusive at the clock
+    plane = (await inst.db.select().from(schema.planes))[0];
+    expect(plane.status).toBe('available');
+    expect(plane.repairUntilSimTime ?? null).toBeNull(); // gate cleared
+  });
+
+  it('runs inside tickOnce even when nothing landed: a past gate flips the plane back', async () => {
+    const inst = await freshDb('repair-tick.db');
+    await inst.db.update(schema.planes)
+      .set({ status: 'repairing', repairUntilSimTime: T0 + 1_500 })
+      .where(eq(schema.planes.id, 'plane-starter'));
+
+    vi.setSystemTime(T0 + 2_000); // one clamped tick at scale 1 → clock T0+2000 ≥ gate; nothing is flying
+    await tickOnce(inst);
+
+    const plane = (await inst.db.select().from(schema.planes))[0];
+    expect(plane.status).toBe('available');
+    expect(plane.repairUntilSimTime ?? null).toBeNull();
+  });
+});
+
 describe('slow to 1× when a landing leaves any plane on the ground (ISS-057)', () => {
   const FROM = 'EDDF';
   const TO = 'LEMD';

lib/sim/engine.ts

@@ -5,7 +5,7 @@ import * as schema from '@/lib/db/schema';
 import { loadAirportsGeoJson } from '@/lib/airports';
 import { haversineKm, initialBearingDeg } from '@/lib/geo';
 import { weatherFor } from '@/lib/weather';
-import { PLANE_TYPES } from '@/lib/game/catalog';
+import { conditionBurnMultiplier, PLANE_TYPES, WEAR_PER_KM } from '@/lib/game/catalog';
 import { SPECIALS } from '@/lib/game/specials';
 import { parseIcaoQueue } from '@/lib/game/state';
 import {
@@ -79,6 +79,9 @@ export async function tickOnce(inst: GameDb): Promise<schema.SimStateRow> {
     await expirePackages(inst, clockMs);
     // ISS-057: remember the landings so the tick can slow down when a plane is left on ground.
     landedThisTick = await deliverPackages(inst, clockMs);
+    // v0.39.0 (ISS-069): repairs whose gate has passed flip back to 'available' — runs even when
+    // nothing landed this tick; BEFORE the spawns so a just-repaired plane gets coverage work too.
+    await finishRepairs(inst, clockMs);
     await spawnOpenPackages(inst, clockMs);
     // AFTER delivery on purpose: a plane that just landed gets work spawned
     // at its new location within the same tick.
@@ -126,6 +129,23 @@ export async function expirePackages(inst: GameDb, clockMs: number): Promise<num
   return n;
 }
 
+// Repairs whose gate has passed flip the plane back to 'available' and clear the gate
+// (v0.39.0, ISS-069) — same shape as expirePackages: one guarded pass over the rows,
+// `<=` inclusive at the clock. Returns the count flipped.
+export async function finishRepairs(inst: GameDb, clockMs: number): Promise<number> {
+  const rows = await inst.db.select().from(schema.planes).where(eq(schema.planes.status, 'repairing'));
+  let n = 0;
+  for (const p of rows) {
+    if (p.repairUntilSimTime !== null && p.repairUntilSimTime <= clockMs) {
+      await inst.db.update(schema.planes)
+        .set({ status: 'available', repairUntilSimTime: null })
+        .where(eq(schema.planes.id, p.id));
+      n++;
+    }
+  }
+  return n;
+}
+
 // Finalize in-flight planes whose arrival time has passed (v0.12.0 delivery):
 // for every package bound to the plane and destined for its dest_icao — 'loaded'
 // ones still inside their deadline are delivered (cash += reward + reputation
@@ -160,16 +180,21 @@ export async function deliverPackages(inst: GameDb, clockMs: number): Promise<nu
 
     // Arrived: progress is exactly 1 here, so remaining fuel is the full-leg weighted burn —
     // wind-adjusted (v0.36.0) by departure weather vs route heading, same factor flyPlane used.
+    // v0.39.0 (ISS-069): broken planes (health ≤ 0 at DEPARTURE) burn BROKEN_BURN_MULTIPLIER × more —
+    // p.health is the pre-landing value, so this stays bit-consistent with livePlane()'s gauge.
     const w = weatherFor(p.locationIcao);
     const landedFuel = fuelAtWeighted(
       p.fuel,
-      type.burnPerKm * windBurnFactor(w.windKt, w.windDirDeg, initialBearingDeg(from.lat, from.lon, to.lat, to.lon)),
+      type.burnPerKm * windBurnFactor(w.windKt, w.windDirDeg, initialBearingDeg(from.lat, from.lon, to.lat, to.lon)) * conditionBurnMultiplier(p.health),
       type.emptyWeightKg,
       type.maxFuel,
       distanceKm,
       1,
     );
 
+    // Wear (v0.39.0, ISS-069): health drops by WEAR_PER_KM per km of this landed leg, clamped at 0.
+    const newHealth = Math.max(0, p.health - WEAR_PER_KM * distanceKm);
+
     // Deliver every bound package whose destination is the airport just reached —
     // runs whether or not a queued leg chains next (ISS-043).
     const onBoard = packageRows.filter((pk) => pk.planeId === p.id && pk.destIcao === to.icao);
@@ -203,10 +228,12 @@ export async function deliverPackages(inst: GameDb, clockMs: number): Promise<nu
       const nextDest = queue[0];
       const next = byIcao.get(nextDest); // unknown ICAO in the queue → cannot chain
       if (next) {
-        // Wind-adjusted requirement for the NEXT leg — it departs from `to` (v0.36.0).
+        // Wind-adjusted requirement for the NEXT leg — it departs from `to` (v0.36.0). v0.39.0 (ISS-069):
+        // the chained leg starts AFTER this landing's wear, so its burn uses newHealth — exactly what
+        // livePlane()/the next landing will compute for that flight.
         const wNext = weatherFor(to.icao);
         const nextRequiredL = requiredFuelFor(
-          type.burnPerKm * windBurnFactor(wNext.windKt, wNext.windDirDeg, initialBearingDeg(to.lat, to.lon, next.lat, next.lon)),
+          type.burnPerKm * windBurnFactor(wNext.windKt, wNext.windDirDeg, initialBearingDeg(to.lat, to.lon, next.lat, next.lon)) * conditionBurnMultiplier(newHealth),
           type.emptyWeightKg,
           type.maxFuel,
           haversineKm(to.lat, to.lon, next.lat, next.lon),
@@ -226,6 +253,7 @@ export async function deliverPackages(inst: GameDb, clockMs: number): Promise<nu
               lat: to.lat,
               lon: to.lon,
               fuel: landedFuel,
+              health: newHealth, // v0.39.0 (ISS-069) — this leg's wear persists into the chained flight
               destIcao: chainedTo,
               departureSimTime: clockMs, // the arrival instant — position is exactly `to`
               queue: JSON.stringify(queue),
@@ -236,6 +264,7 @@ export async function deliverPackages(inst: GameDb, clockMs: number): Promise<nu
               lat: to.lat,
               lon: to.lon,
               fuel: landedFuel,
+              health: newHealth, // v0.39.0 (ISS-069) — this leg's wear persists on the grounded plane
               departureSimTime: null,
               destIcao: null,
               queue: JSON.stringify(queue),