diff --git a/CHANGELOG.md b/CHANGELOG.md
index 4850335..8b1d5d5 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,5 +1,9 @@
 # Changelog
 
+## v0.62.0 — 2026-09-23 07:36
+- **Fixed 24x world clock (#135).** Finalized the closed issue #117 spec: the world clock runs at the fixed `WORLD_TIME_SCALE = 24` while any plane is flying or in repair, and stays FROZEN when the whole fleet is grounded — replacing v0.56.0's idle slowdown (`IDLE_WORLD_TIME_SCALE = WORLD_TIME_SCALE / 24`, ISS-128). **Production rate is now exactly 24x regardless of legacy stored values:** `tickOnce` in `lib/sim/engine.ts` computes `advanceMs = advance ? min(elapsed, MAX_TICK_ELAPSED_MS) × scale : 0` where `scale = FLIGHT_TEST_HOOKS === '1' ? sim.timeScale : WORLD_TIME_SCALE` — pre-v0.52.0 saves hold `timeScale: 1000` (the old UI ladder), which is why the live instance still ran at ×1000; only deployments with the env var set honor the stored override written by `POST /api/test/set-timescale` (range [1, 100_000], kept for tests). A frozen tick skips expiry/delivery/repair/spawn entirely and only updates `lastRealTickMs`, so resuming activity never fast-forwards the frozen span. The client mirror (`advanceSimClock` in `lib/useSimClock.ts`) holds its anchor value while grounded, so polls re-anchor without any jump. Removed: `IDLE_WORLD_TIME_SCALE` from `lib/worldClock.ts`, and — **separate finding** — `FLIGHT_TEST_HOOKS: "1"` from the production `docker-compose.yml`: it enabled the `/api/test/*` hooks in prod AND (pre-gate) made the live instance honor its stale stored 1000; e2e runs only in CI against `docker-compose.ci.yml`, which sets the var itself. Unchanged on purpose: the ~1 s background tick (started at boot), the test hook endpoint, and the inert legacy columns `paused`/`lastSelectedTimeScale` (nothing reads them; no migration — per #117 saves reset when multiplayer ships). The OpenAPI description of `/api/state` ("while no plane is flying or in repair the clock stays frozen") now matches the code.
+- **Tests.** Unit: `lib/sim/engine.test.ts` — both rate branches pinned: with `FLIGHT_TEST_HOOKS=1` stubbed (the file's default, like CI) stored overrides are honored; a new production test unsets the var and proves a legacy stored `timeScale: 1000` still advances at exactly ×24. Grounded-fleet tests pin a FROZEN clock (no idle creep, resume-without-catch-up after takeoff, raised timeScale ignored while grounded); describe renamed to "grounded fleet freezes the world clock (#135)" and pins `WORLD_TIME_SCALE = 24`. `lib/useSimClock.test.ts` — the grounded case asserts staying exactly at the anchor value. E2E: `e2e/sim.spec.ts`'s idle test becomes an exact freeze (delta === 0 after ~2.5 s of idleness); `e2e/state.spec.ts`'s restart test tightens from bounded delta to EXACT clock equality across `docker compose restart`; `e2e/right-pane.spec.ts` verifies the frozen clock, then asserts the abandon-penalty preview matches the server exactly (zero drift under a frozen clock — replaces the DRIFT_MS slope tolerance); `e2e/events.spec.ts` relaxes strict clock advance between SSE frames to non-decreasing (a grounded fleet pushes identical-clockMs frames; advance itself is pinned in sim.spec.ts). The activateWorld/deactivateWorld wrappers are unchanged — a repairing plane still means full scale.
+
 ## v0.61.0 — 2026-09-23 07:12
 - **Special remote airports (ISS-097).** The world dataset was curated to `large_airport` only, so genuinely empty regions — Antarctica, the high Arctic, Alaska, northern Canada and far islands — had no markers at all. New pure function `isRemote(airports, icao)` in `lib/airports.ts` (reusing the existing `haversineKm` from `lib/geo.ts`): an airport is remote when no other member of the given list lies within `REMOTE_RADIUS_KM = 1000`. The curation in `scripts/build-world-airports.mjs` now runs over ALL fixed-wing rows: every large_airport (unchanged clustering) plus every non-large row that is remote against the kept set; same-station twins (two strips <40 km apart at one base) collapse via the same greedy 40 km clustering. `data/airports_world.csv` grows from 1119 → **1483 rows** (+364 remote airports), including Rothera (EGAR), Halley (EGAH) and Showa skiway (AT25) in Antarctica; Grise Fiord (CYGZ), Alert (CYLT), Ny-Ålesund (ENAS — Svalbard's only marker within 1000 km of a large airport) and Wrangel Island (UHMZ) in the Arctic; Bethel (PABR) and other Alaska strips; Canadian-Arctic smalls; and far islands such as Easter (SCIP), Canton (PCIS), Henderson/Pago Pago (PMDY) and Ascension (FHAW). The only change to a pre-existing row is an upstream `home_link` refresh on CYLW. New airports become contract origins/destinations and map markers unchanged — the most isolated airport in the new set (Easter Island) has its nearest neighbour 2599 km away, well under the 9000 km job cap, so every origin stays flyable; `filterWorldAirports` already accepts small/medium/seaplane types, so no runtime change was needed.
 - **Tests.** Unit +4 in `lib/airports.test.ts`: a synthetic radius boundary (equator pair at ~945 km vs ~1052 km), real coordinates (Frankfurt↔Amsterdam is not remote; McMurdo vs Christchurch is), an unknown ICAO returning false, and the committed-dataset curation invariant — every non-large row has no large airport within 1000 km and at least one non-large row exists.
diff --git a/docker-compose.yml b/docker-compose.yml
index d4049ae..f43545f 100644
--- a/docker-compose.yml
+++ b/docker-compose.yml
@@ -8,11 +8,10 @@ services:
       # Game state SQLite (v0.6.0): seeded on first run, must survive rebuilds.
       # Dedicated dir — do NOT mount over /app/data (would mask airports_world.csv).
       - "./db:/app/db"
-    environment:
-      # e2e-only affordance (v0.7.0): enables POST /api/test/create-package and
-      # /api/test/expire-package so the suites can force known routes/expiries;
-      # 404 without this var.
-      FLIGHT_TEST_HOOKS: "1"
+    # No environment on purpose (#135, v0.62.0): FLIGHT_TEST_HOOKS must NOT be set in production —
+    # it enables the /api/test/* hooks AND makes tickOnce honor legacy stored timeScale values
+    # (pre-v0.52.0 saves hold 1000). The e2e suite runs only in CI against docker-compose.ci.yml,
+    # which sets the var itself.
     networks:
       - dev_net
     labels:
diff --git a/e2e/actions.spec.ts b/e2e/actions.spec.ts
index 504a5da..3d9857a 100644
--- a/e2e/actions.spec.ts
+++ b/e2e/actions.spec.ts
@@ -98,10 +98,10 @@ async function setHealth(page: Page, planeId: string, fields: Record<string, unk
   expect(res.status()).toBe(200);
 }
 
-// A fully grounded fleet only advances at the idle real-time rate (ISS-128) — put the starter in
-// repair so the clock runs at FULL scale for tests that need fast-forwarding. The €1.5k repair cost
-// is why the expiry test captures its cash/rep baseline AFTER deactivateWorld; deactivateWorld
-// restores full health and no gate afterwards.
+// A fully grounded fleet freezes the world clock (#135) — put the starter in repair so the clock
+// runs at FULL scale for tests that need fast-forwarding. The €1.5k repair cost is why the expiry
+// test captures its cash/rep baseline AFTER deactivateWorld; deactivateWorld restores full health
+// and no gate afterwards.
 async function activateWorld(page: Page): Promise<void> {
   await setHealth(page, 'plane-starter', { health: 50 });
   expect((await page.request.post('/api/planes/plane-starter/repair')).status()).toBe(200);
@@ -344,9 +344,9 @@ test('expired packages deliver and abandon with no reward and no penalty', async
     expect(res.ok()).toBeTruthy();
   }
 
-  // A fully grounded fleet only advances at the idle real-time rate (ISS-128) — put the starter in
-  // repair for the expiry window so scale 1000 can fast-forward past both deadlines quickly. The €1.5k
-  // repair cost is why the cash/rep baseline below is captured AFTER deactivateWorld, not before it.
+  // A fully grounded fleet freezes the world clock (#135) — put the starter in repair for the expiry
+  // window so scale 1000 can fast-forward past both deadlines quickly. The €1.5k repair cost is why
+  // the cash/rep baseline below is captured AFTER deactivateWorld, not before it.
   await activateWorld(page);
   try {
     // Fast-forward past both deadlines — the tick flips loaded → expired (slot kept).
diff --git a/e2e/events.spec.ts b/e2e/events.spec.ts
index d113d27..f80bae6 100644
--- a/e2e/events.spec.ts
+++ b/e2e/events.spec.ts
@@ -63,8 +63,10 @@ test('GET /api/events streams state snapshots over SSE', async () => {
   }
 
   // The initial snapshot arrives on connect; the second comes from a background tick within ~1 s.
+  // A grounded fleet freezes the clock (#135), so consecutive frames may carry the SAME clockMs —
+  // non-decreasing is what proves real pushes, not replays (advance itself is pinned in sim.spec.ts).
   expect(clocks.length).toBeGreaterThanOrEqual(2);
-  expect(clocks[1]).toBeGreaterThan(clocks[0]); // clock advanced between pushes — real updates, not replays
+  expect(clocks[1]).toBeGreaterThanOrEqual(clocks[0]);
 
   // ISS-133: no terminal package history in any frame (the DB keeps it forever; frames must not),
   // and a bounded frame size even on an instance with long-running history (~597 KB pre-v0.59.0).
diff --git a/e2e/panes.spec.ts b/e2e/panes.spec.ts
index 859862d..1c928b7 100644
--- a/e2e/panes.spec.ts
+++ b/e2e/panes.spec.ts
@@ -39,9 +39,9 @@ async function setHealth(page: Page, planeId: string, fields: Record<string, unk
   expect(res.status()).toBe(200);
 }
 
-// A fully grounded fleet only advances at the idle real-time rate (ISS-128) — put the starter in
-// repair so the clock runs at FULL scale for tests that need fast-forwarding. The €1.5k repair cost
-// is irrelevant to every spec's relative cash assertions; deactivateWorld restores full health and no gate afterwards.
+// A fully grounded fleet freezes the world clock (#135) — put the starter in repair so the clock
+// runs at FULL scale for tests that need fast-forwarding. The €1.5k repair cost is irrelevant to
+// every spec's relative cash assertions; deactivateWorld restores full health and no gate afterwards.
 async function activateWorld(page: Page): Promise<void> {
   await setHealth(page, STARTER, { health: 50 });
   expect((await page.request.post(`/api/planes/${STARTER}/repair`)).status()).toBe(200);
@@ -151,7 +151,7 @@ test('sim clock ticks smoothly between polls at the fixed world rate (ISS-007, I
   // 409s on non-available planes — it must be grounded before activateWorld.
   await flyHomeViaApi(page);
   await setScale(page, WORLD); // self-heal may have left the fast test rate behind
-  // A grounded fleet only advances at the idle real-time rate (ISS-128) — put the starter in repair for full scale.
+  // A fully grounded fleet freezes the world clock (#135) — put the starter in repair for full scale.
   await activateWorld(page);
   try {
     await page.goto('/');
diff --git a/e2e/right-pane.spec.ts b/e2e/right-pane.spec.ts
index 1390004..548c3a2 100644
--- a/e2e/right-pane.spec.ts
+++ b/e2e/right-pane.spec.ts
@@ -274,26 +274,17 @@ test('on-board list: fly-to-destination + abandon with penalty preview; flying p
 
   // The abandon button previews the penalty at its snapshot's clock (same formula as the server).
   // The fleet is grounded here (the starter just loaded; workers:1 and every spec's cleanup leave no
-  // other planes), so the world runs at the idle real-time rate (ISS-128) — verify it actually did,
-  // then bound the UI's staleness instead of racing a frozen clock.
+  // other planes), so the world clock is FROZEN (#135) — verify it actually is, then the preview must
+  // match the server exactly: a frozen clock means zero drift between any two snapshots.
   const c0 = (await getState(page)).simState.clockMs;
-  const t0 = Date.now();
   await new Promise((r) => setTimeout(r, 1_500)); // > one background-tick interval
   const state = await getState(page);
-  const idleDelta = state.simState.clockMs - c0;
-  expect(idleDelta, 'world should advance at the idle real-time rate while grounded (ISS-128)').toBeGreaterThan(0);
-  expect(idleDelta).toBeLessThan((Date.now() - t0) * WORLD); // clearly below the full world rate
+  expect(state.simState.clockMs - c0, 'the grounded clock must stay frozen (#135)').toBe(0);
 
-  // The UI renders the penalty from its last snapshot — up to one poll interval (~1 s, useGameState)
-  // older than `state`, i.e. ≤ ~2 game-seconds of clock drift at the idle real-time rate (ISS-128).
-  // Allow the formula's slope over that window instead of an exact string match.
-  const DRIFT_MS = 3_000; // a couple of poll intervals at the idle rate (= 1), margin for slow CI boxes
-  const span = pkg.deadlineSimTime - pkg.createdSimTime;
   const penaltyText = ((await page.getByTestId(`abandon-penalty-${pkg.id}`).textContent()) ?? '').replace(/[^0-9.]/g, '');
   expect(Number.isFinite(Number(penaltyText)), `penalty text: ${penaltyText}`).toBe(true);
   const expectedPenalty = penaltyFor(pkg.reward, pkg.createdSimTime, pkg.deadlineSimTime, state.simState.clockMs);
-  const slopePerGameMs = (pkg.reward * 0.45) / span; // abandonPenaltyPct's SPAN across the package lifetime
-  expect(Math.abs(Number(penaltyText) - expectedPenalty)).toBeLessThanOrEqual(slopePerGameMs * DRIFT_MS + 0.01);
+  expect(Number(penaltyText), 'frozen clock → the preview matches the server exactly').toBe(expectedPenalty);
 
   // Fly to the destination through the UI — the button is the destination's name.
   const flyBtn = page.getByTestId(`fly-to-${pkg.id}`);
diff --git a/e2e/sim.spec.ts b/e2e/sim.spec.ts
index ca39127..a73b1df 100644
--- a/e2e/sim.spec.ts
+++ b/e2e/sim.spec.ts
@@ -1,15 +1,14 @@
 import { test, expect, type Page } from '@playwright/test';
 
-// v0.52.0 (ISS-117) fixed world clock against the live origin: a fully grounded fleet slowing to
-// real time instead of freezing (ISS-128), background-tick advance at a raised rate while
-// something is active, package expiry via the FLIGHT_TEST_HOOKS hooks (enabled in docker-compose.yml),
-// and market top-up.
+// v0.52.0 (ISS-117), finalized in #135: fixed world clock against the live origin — a fully
+// grounded fleet freezes the clock, background-tick advance at a raised rate while something is
+// active, package expiry via the FLIGHT_TEST_HOOKS hooks (enabled in docker-compose.yml), and
+// market top-up.
 
 // Must match lib/sim/engine.ts — kept in sync manually (same pattern as MIN_ZOOM/MAX_ZOOM in map.spec.ts).
 const MAX_TICK_ELAPSED_MS = 2_000;
 const SCALE = 1000; // test rate for fast-forwarding legs
 const WORLD = 24; // the fixed world rate (ISS-117) — must match lib/worldClock.ts
-const IDLE = 1; // the idle real-time rate (ISS-128) — must match IDLE_WORLD_TIME_SCALE in lib/worldClock.ts (= WORLD / 24)
 const MAX_DELTA_PER_TICK = MAX_TICK_ELAPSED_MS * SCALE; // 2_000_000 game ms per tick at scale 1000
 // Must match MARKET_TARGET_OPEN_PACKAGES in lib/game/seed.ts.
 const MARKET_TARGET = 10;
@@ -48,10 +47,9 @@ async function setHealth(page: Page, planeId: string, fields: Record<string, unk
   expect(res.status()).toBe(200);
 }
 
-// A fully grounded fleet only advances at the idle real-time rate (ISS-128) — put the starter in
-// repair so the clock runs at FULL scale for tests that need fast-forwarding. The €1.5k repair
-// cost is irrelevant to every spec's relative cash assertions; deactivateWorld restores full health
-// and no gate afterwards.
+// A fully grounded fleet freezes the world clock (#135) — put the starter in repair so the clock
+// runs at FULL scale for tests that need fast-forwarding. The €1.5k repair cost is irrelevant to
+// every spec's relative cash assertions; deactivateWorld restores full health and no gate afterwards.
 async function activateWorld(page: Page): Promise<void> {
   await setHealth(page, STARTER, { health: 50 });
   expect((await page.request.post(`/api/planes/${STARTER}/repair`)).status()).toBe(200);
@@ -73,25 +71,15 @@ test.afterEach(async ({ page }) => {
   await setScale(page, WORLD);
 });
 
-test('a fully grounded fleet slows the clock to real time instead of freezing it (ISS-128)', async ({ page }) => {
+test('a fully grounded fleet freezes the world clock (#135)', async ({ page }) => {
   const s = await getState(page);
   expect(s.planes.every((p) => p.status === 'available'), 'fleet should be grounded at spec start').toBe(true);
 
-  const t0 = Date.now();
   const c0 = s.simState.clockMs;
   await sleep(2_500); // ~2.5 s of real idleness — several background ticks plus the reads below
   const after = await getState(page);
-  const elapsedReal = Date.now() - t0;
 
-  const delta = after.simState.clockMs - c0;
-  expect(delta, 'the idle clock must advance (no longer frozen)').toBeGreaterThan(0);
-  // ≈ real time: each tick counts min(gap, MAX_TICK_ELAPSED_MS) × IDLE rate, so the total can only fall
-  // short of the wall span when a tick gap was clamped — worst case is one clamped idle-rate tick.
-  expect(delta).toBeGreaterThanOrEqual(Math.min(elapsedReal * IDLE * 0.5, MAX_TICK_ELAPSED_MS * IDLE));
-  // …and never more than the wall span itself (plus one clamp of pre-read downtime for slow boxes)…
-  expect(delta).toBeLessThanOrEqual(elapsedReal + MAX_TICK_ELAPSED_MS);
-  // …which is clearly below the full world rate: at ×24 this window would be ≥ ~60 game seconds.
-  expect(delta).toBeLessThan(elapsedReal * WORLD);
+  expect(after.simState.clockMs - c0, 'the grounded clock must stay frozen').toBe(0);
 });
 
 test('timeScale 1000 advances the clock by roughly real-time × 1000 between polls', async ({ page }) => {
diff --git a/e2e/state.spec.ts b/e2e/state.spec.ts
index c19b308..4651c82 100644
--- a/e2e/state.spec.ts
+++ b/e2e/state.spec.ts
@@ -8,9 +8,6 @@ import { test, expect } from '@playwright/test';
 const repoRoot = path.join(__dirname, '..');
 const composeArgs = process.env.E2E_COMPOSE_ARGS ?? '';
 
-// Must match lib/sim/engine.ts — kept in sync manually (same pattern as e2e/sim.spec.ts).
-const MAX_TICK_ELAPSED_MS = 2_000;
-
 interface StateBody {
   account: { cash: number; reputation: number };
   simState: { clockMs: number }; // ISS-117: the snapshot carries only the game clock
@@ -45,9 +42,8 @@ test('GET /api/state returns a seeded snapshot', async ({ page }) => {
 test('state survives a container restart (sim clock + account persisted)', async ({ page }) => {
   test.setTimeout(180_000);
 
-  // Self-heal to a fully grounded fleet first — while idle the clock advances at real time
-  // (ISS-128), so the post-restart snapshot is bounded by one clamped tick of downtime plus live
-  // ticks, not byte-for-byte identical.
+  // Self-heal to a fully grounded fleet first — a grounded fleet freezes the world clock (#135),
+  // so no tick advances it across the restart and the post-restart clock is exactly unchanged.
   await expect
     .poll(async () => {
       const res = await page.request.get('/api/state');
@@ -60,7 +56,6 @@ test('state survives a container restart (sim clock + account persisted)', async
   const resBefore = await page.request.get('/api/state');
   expect(resBefore.status()).toBe(200);
   const before = (await resBefore.json()) as StateBody;
-  const tBefore = Date.now();
 
   execSync(`docker compose ${composeArgs} restart flight`, { cwd: repoRoot, stdio: 'pipe' });
 
@@ -80,17 +75,12 @@ test('state survives a container restart (sim clock + account persisted)', async
 
   expect(after).toBeDefined();
   const a = after!;
-  const tAfter = Date.now();
 
   // The DB file on the volume must be loaded, not re-seeded (PLAN.md: "sim clock persisted across
-  // sessions"): account and entity ids are byte-identical. With the fleet grounded above, ISS-128
-  // advances the clock at real time while idle — bounded tolerance instead of exact equality: no
-  // ticks run while the container is down, so the first post-restart tick counts the downtime
-  // clamped to MAX_TICK_ELAPSED_MS × IDLE rate (= 1), and every other counted gap lies inside the
-  // live wall span [tBefore, tAfter] at that same rate. A re-seed would reset clockMs backwards.
-  const delta = a.simState.clockMs - before.simState.clockMs;
-  expect(delta).toBeGreaterThanOrEqual(0); // never goes backwards — not re-seeded
-  expect(delta).toBeLessThanOrEqual(MAX_TICK_ELAPSED_MS + (tAfter - tBefore));
+  // sessions"): account and entity ids are byte-identical. With the fleet grounded above, the world
+  // clock is FROZEN (#135) — no tick advances it while the container is down or after restart, so
+  // the post-restart clock is EXACTLY unchanged; a re-seed would reset clockMs backwards instead.
+  expect(a.simState.clockMs - before.simState.clockMs).toBe(0);
   expect(a.account.cash).toBe(before.account.cash);
   expect(a.account.reputation).toBe(before.account.reputation);
   expect(a.planes.map((p) => p.id).sort()).toEqual(before.planes.map((p) => p.id).sort());
diff --git a/lib/sim/engine.test.ts b/lib/sim/engine.test.ts
index 7150504..f26fa96 100644
--- a/lib/sim/engine.test.ts
+++ b/lib/sim/engine.test.ts
@@ -16,7 +16,6 @@ import {
   deliverPackages,
   expirePackages,
   finishRepairs,
-  IDLE_WORLD_TIME_SCALE,
   MAX_TICK_ELAPSED_MS,
   reputationGainFor,
   shouldAdvanceTime,
@@ -31,9 +30,9 @@ import {
 // public tickNow()/setTestTimeScale() wrappers (singleton + lock) are covered by the e2e suite
 // (every spec's setScale helper hits /api/test/set-timescale; sim.spec.ts pins its validation).
 
-// ISS-117 / ISS-128: fresh DBs seed a GROUNDED starter, so any test that needs FULL-scale advance
-// must put a plane in flight first (a grounded fleet only advances at the idle real-time rate) —
-// departureSimTime at the game-clock origin keeps its arrival hours away.
+// #135: fresh DBs seed a GROUNDED starter, so any test that needs clock advance must put a plane in
+// flight first (a fully grounded fleet freezes the world) — departureSimTime at the game-clock
+// origin keeps its arrival hours away.
 async function makeWorldActive(inst: Awaited<ReturnType<typeof openGameDb>>) {
   await inst.db.update(schema.planes)
     .set({ status: 'flying', destIcao: 'LEMD', departureSimTime: STARTING_CLOCK_MS })
@@ -46,11 +45,15 @@ const T0 = 1_750_000_000_000; // seed moment / fake "now" at DB open
 beforeAll(async () => {
   vi.useFakeTimers();
   vi.setSystemTime(T0);
+  // #135 (v0.62.0): this file exercises the FLIGHT_TEST_HOOKS branch of tickOnce — stored
+  // sim.timeScale overrides are only honored when the env var is set, exactly like CI.
+  vi.stubEnv('FLIGHT_TEST_HOOKS', '1');
   dir = await fs.mkdtemp(path.join(os.tmpdir(), 'flight-sim-'));
 });
 
 afterAll(async () => {
   vi.useRealTimers();
+  vi.unstubAllEnvs();
   await fs.rm(dir, { recursive: true, force: true });
 });
 
@@ -62,7 +65,7 @@ async function freshDb(name: string) {
 describe('tickOnce — clock advance', () => {
   it('advances the clock by elapsed real ms × timeScale', async () => {
     const inst = await freshDb('scale.db');
-    await makeWorldActive(inst); // a grounded fleet would slow the world to the idle real-time rate (ISS-128)
+    await makeWorldActive(inst); // a fully grounded fleet freezes the clock (#135)
     vi.setSystemTime(T0 + 1_000); // one real second later
     await inst.db.update(schema.simState).set({ timeScale: 5 });
 
@@ -72,30 +75,48 @@ describe('tickOnce — clock advance', () => {
     expect(sim.lastRealTickMs).toBe(T0 + 1_000);
   });
 
-  it('a fully grounded fleet advances at the idle real-time rate, not frozen (ISS-128)', async () => {
-    const inst = await freshDb('idle.db'); // seeded starter is on the ground → idle
+  it('production (no FLIGHT_TEST_HOOKS): a legacy stored timeScale is ignored — always WORLD_TIME_SCALE (#135)', async () => {
+    const inst = await freshDb('prod-rate.db');
+    await makeWorldActive(inst);
+    await inst.db.update(schema.simState).set({ timeScale: 1_000 }); // what a pre-v0.52.0 save holds
+
+    vi.setSystemTime(T0 + 1_000);
+    const saved = process.env.FLIGHT_TEST_HOOKS;
+    delete process.env.FLIGHT_TEST_HOOKS;
+    let sim: schema.SimStateRow;
+    try {
+      sim = await tickOnce(inst);
+    } finally {
+      if (saved !== undefined) process.env.FLIGHT_TEST_HOOKS = saved; // restore the stubbed value
+    }
+
+    expect(sim.clockMs).toBe(STARTING_CLOCK_MS + 1_000 * WORLD_TIME_SCALE); // ×24, NOT ×1000
+  });
+
+  it('a fully grounded fleet freezes the clock, then resumes with no catch-up (#135)', async () => {
+    const inst = await freshDb('idle.db'); // seeded starter is on the ground → frozen
 
     vi.setSystemTime(T0 + 3_600_000); // an hour of real idleness
     let sim = await tickOnce(inst);
-    expect(sim.clockMs).toBe(STARTING_CLOCK_MS + MAX_TICK_ELAPSED_MS * IDLE_WORLD_TIME_SCALE); // clamped to one idle-rate tick — no fast-forward, no freeze
+    expect(sim.clockMs).toBe(STARTING_CLOCK_MS); // frozen — no fast-forward, no idle creep
     expect(sim.lastRealTickMs).toBe(T0 + 3_600_000);
 
-    // A plane takes off: resumes from where it stopped, with NO catch-up for the idle time.
+    // A plane takes off: resumes from where it stopped, with NO catch-up for the frozen time.
     await inst.db.update(schema.simState).set({ timeScale: 60 });
     await makeWorldActive(inst);
     vi.setSystemTime(T0 + 3_600_500);
     sim = await tickOnce(inst);
-    expect(sim.clockMs).toBe(STARTING_CLOCK_MS + MAX_TICK_ELAPSED_MS * IDLE_WORLD_TIME_SCALE + 500 * 60); // only the 500 ms since activity × 60
+    expect(sim.clockMs).toBe(STARTING_CLOCK_MS + 500 * 60); // only the 500 ms since activity × 60
   });
 
-  it('a grounded fleet ignores any raised timeScale — the idle rate wins (ISS-128)', async () => {
+  it('a grounded fleet ignores any raised timeScale — frozen regardless (#135)', async () => {
     const inst = await freshDb('idle-scale.db');
     await inst.db.update(schema.simState).set({ timeScale: 1_000 }); // FLIGHT_TEST_HOOKS-style override
 
     vi.setSystemTime(T0 + 1_000);
     const sim = await tickOnce(inst);
 
-    expect(sim.clockMs).toBe(STARTING_CLOCK_MS + 1_000 * IDLE_WORLD_TIME_SCALE); // real time, NOT ×1000
+    expect(sim.clockMs).toBe(STARTING_CLOCK_MS); // frozen, NOT ×1000
   });
 
   it('clamps long absences: a 1-hour gap advances at most MAX_TICK_ELAPSED_MS × scale', async () => {
@@ -586,13 +607,12 @@ describe('finishRepairs (v0.39.0, ISS-069)', () => {
   });
 });
 
-describe('idle slowdown — a grounded fleet slows the world to real time (ISS-128)', () => {
-  it('pins IDLE_WORLD_TIME_SCALE = WORLD_TIME_SCALE / 24, i.e. exactly real time', () => {
-    expect(IDLE_WORLD_TIME_SCALE).toBe(WORLD_TIME_SCALE / 24);
-    expect(IDLE_WORLD_TIME_SCALE).toBe(1); // one game-second per real second
+describe('grounded fleet freezes the world clock (#135)', () => {
+  it('pins WORLD_TIME_SCALE = 24 — the single fixed world rate (ISS-117)', () => {
+    expect(WORLD_TIME_SCALE).toBe(24);
   });
 
-  it('shouldAdvanceTime: grounded/empty fleets are idle; any flying or repairing plane advances', () => {
+  it('shouldAdvanceTime: grounded/empty fleets are frozen; any flying or repairing plane advances', () => {
     expect(shouldAdvanceTime([])).toEqual({ advance: false, flying: 0, repairing: 0 });
     expect(shouldAdvanceTime([{ status: 'available' }, { status: 'available' }])).toEqual({ advance: false, flying: 0, repairing: 0 });
     expect(shouldAdvanceTime([{ status: 'flying' }, { status: 'available' }])).toEqual({ advance: true, flying: 1, repairing: 0 });
@@ -600,13 +620,13 @@ describe('idle slowdown — a grounded fleet slows the world to real time (ISS-1
     expect(shouldAdvanceTime([{ status: 'flying' }, { status: 'repairing' }])).toEqual({ advance: true, flying: 1, repairing: 1 });
   });
 
-  it('a fully grounded fleet advances at the idle rate but keeps tracking real time', async () => {
-    const inst = await freshDb('idle-pause.db'); // seeded starter is on the ground → idle
+  it('a fully grounded fleet stays frozen but keeps tracking real time', async () => {
+    const inst = await freshDb('idle-pause.db'); // seeded starter is on the ground → frozen
     vi.setSystemTime(T0 + 3_600_000);
 
     const sim = await tickOnce(inst);
 
-    expect(sim.clockMs).toBe(STARTING_CLOCK_MS + MAX_TICK_ELAPSED_MS * IDLE_WORLD_TIME_SCALE); // real-time rate, clamped — not frozen
+    expect(sim.clockMs).toBe(STARTING_CLOCK_MS); // frozen — no idle creep
     expect(sim.lastRealTickMs).toBe(T0 + 3_600_000); // …and the real-time anchor moved on
   });
 
diff --git a/lib/sim/engine.ts b/lib/sim/engine.ts
index 500a887..80c36f9 100644
--- a/lib/sim/engine.ts
+++ b/lib/sim/engine.ts
@@ -9,7 +9,7 @@ import { FUEL_DISCOUNT_PER_REP, FUEL_PRICE_PER_L, MAX_FUEL_DISCOUNT, PLANE_TYPES
 import { SPECIALS } from '@/lib/game/specials';
 import { getStateSnapshot, parseIcaoQueue, sseFrame } from '@/lib/game/state';
 import { broadcast } from '@/lib/sse';
-import { IDLE_WORLD_TIME_SCALE } from '@/lib/worldClock';
+
 import {
   generatePackage,
   MARKET_TARGET_OPEN_PACKAGES,
@@ -22,10 +22,12 @@ import { arrivalTimeFor, fuelAtWeighted, requiredFuelFor, windBurnFactor } from
 
 // Server-authoritative sim engine (v0.7.0). ISS-117 (v0.52.0): the clock advances on a background
 // tick (~1 s, started at boot from instrumentation.ts) AND on every read/action — both through the
-// same locked tickOnce path. Each tick advances by (real ms since last tick) × timeScale, clamped
-// per tick so long absences never fast-forward the game; while no plane is flying or in repair the
-// world slows to real time instead of freezing (IDLE_WORLD_TIME_SCALE, ISS-128 v0.56.0), and
-// lastRealTickMs always keeps tracking real time.
+// same locked tickOnce path. Each tick advances by (real ms since last tick) × scale, clamped per
+// tick so long absences never fast-forward the game; while no plane is flying or in repair the
+// world clock stays FROZEN (#135 v0.62.0 — final ISS-117 semantics), and lastRealTickMs always
+// keeps tracking real time, so resuming activity never fast-forwards the frozen span. Scale is the
+// fixed WORLD_TIME_SCALE in production; only FLIGHT_TEST_HOOKS deployments honor sim.timeScale
+// (the test-hook override) — legacy saves may hold stale values (#135).
 
 // Clamp constant: max real-time gap counted by a single tick. Chosen at 2000 ms — comfortably above
 // both the client poll interval (~1 s) and the background-tick interval, so active play advances
@@ -33,9 +35,10 @@ import { arrivalTimeFor, fuelAtWeighted, requiredFuelFor, windBurnFactor } from
 // 2 s × scale.
 export const MAX_TICK_ELAPSED_MS = 2_000;
 
-// ISS-117 / ISS-128: the fixed world rates — re-exported here so server code and tests have one
-// familiar home (full rate while something is active, real-time rate while fully grounded).
-export { IDLE_WORLD_TIME_SCALE, WORLD_TIME_SCALE } from '@/lib/worldClock';
+// ISS-117: the fixed world rate — imported for tickOnce, re-exported so server code and tests
+// have one familiar home.
+import { WORLD_TIME_SCALE } from '@/lib/worldClock';
+export { WORLD_TIME_SCALE };
 
 // Reputation gain per delivered package: BASE + PER_KM × great-circle km, rounded
 // to 2 decimals (reputation is REAL). A short hop (~300 km) earns ~1.15 rep, a
@@ -64,10 +67,10 @@ function withLock<T>(fn: () => Promise<T>): Promise<T> {
 
 // --- Tick core (takes a GameDb so unit tests can inject their own instance) ---
 
-// ISS-117 / ISS-128: idle decision — pure, so unit tests feed it synthetic fleets. The world clock
-// runs at full scale only while something is happening (at least one plane flying OR in repair); a
-// fully grounded fleet slows it to IDLE_WORLD_TIME_SCALE (real time) instead of freezing it, so
-// expiries/spawns keep running until a dispatch or repair starts.
+// #135: advance decision — pure, so unit tests feed it synthetic fleets. The world clock runs at
+// full scale only while something is happening (at least one plane flying OR in repair); a fully
+// grounded fleet freezes it entirely — no expiry/spawn/repair progress until a dispatch or repair
+// starts again.
 export function shouldAdvanceTime(planes: Array<{ status: string }>): { advance: boolean; flying: number; repairing: number } {
   let flying = 0;
   let repairing = 0;
@@ -84,15 +87,16 @@ export async function tickOnce(inst: GameDb): Promise<schema.SimStateRow> {
   if (!sim) throw new Error('sim_state row missing');
 
   const nowMs = Date.now();
-  // ISS-128: a fully grounded fleet slows the world to real time (IDLE_WORLD_TIME_SCALE) instead of
-  // freezing it — packages keep spawning/expiring while idle. An active fleet keeps its full scale,
-  // including any FLIGHT_TEST_HOOKS override in sim.timeScale. lastRealTickMs always tracks real
-  // time, so resuming activity never fast-forwards the idle duration.
+  // #135: a fully grounded fleet freezes the world — no advance, no expiry/spawn/repair progress.
+  // lastRealTickMs always tracks real time, so resuming activity never fast-forwards the frozen span.
   const planeRows = await inst.db.select().from(schema.planes);
   const { advance } = shouldAdvanceTime(planeRows.map((p) => ({ status: p.status })));
+  // #135 (v0.62.0): production ALWAYS runs at the fixed world rate — legacy saves may hold a stale
+  // timeScale (e.g. 1000 from pre-v0.52.0 UI controls, or an old e2e run against the live instance).
+  // Only FLIGHT_TEST_HOOKS deployments honor sim.timeScale, which POST /api/test/set-timescale writes.
+  const scale = process.env.FLIGHT_TEST_HOOKS === '1' ? sim.timeScale : WORLD_TIME_SCALE;
   const elapsed = Math.max(0, nowMs - sim.lastRealTickMs);
-  const scale = advance ? sim.timeScale : IDLE_WORLD_TIME_SCALE;
-  const advanceMs = Math.min(elapsed, MAX_TICK_ELAPSED_MS) * scale;
+  const advanceMs = advance ? Math.min(elapsed, MAX_TICK_ELAPSED_MS) * scale : 0;
   const clockMs = Math.round(sim.clockMs + advanceMs);
 
   if (advanceMs > 0) {
diff --git a/lib/useSimClock.test.ts b/lib/useSimClock.test.ts
index 1b39c28..cfc61ce 100644
--- a/lib/useSimClock.test.ts
+++ b/lib/useSimClock.test.ts
@@ -1,11 +1,11 @@
 import { describe, expect, it } from 'vitest';
 import { advanceSimClock, type SimClockAnchor } from './useSimClock';
-import { IDLE_WORLD_TIME_SCALE, WORLD_TIME_SCALE } from './worldClock';
+import { WORLD_TIME_SCALE } from './worldClock';
 
 // ISS-007 (v0.16.1) — the pure extrapolation core of lib/useSimClock.ts. The hook itself is a
 // thin setInterval + re-sync wrapper covered by e2e (panes.spec.ts "ticks smoothly between polls");
-// this suite pins the math: game time advances real-time × WORLD_TIME_SCALE, and slows to
-// real-time × IDLE_WORLD_TIME_SCALE while idle (ISS-128).
+// this suite pins the math: game time advances real-time × WORLD_TIME_SCALE while something is
+// flying or in repair, and stays frozen at the anchor value while fully grounded (#135).
 
 const anchor = (over: Partial<SimClockAnchor> = {}): SimClockAnchor => ({
   clockMs: 1_750_000_000_000,
@@ -25,10 +25,10 @@ describe('advanceSimClock', () => {
     expect(advanceSimClock(anchor(), 1_000_000)).toBe(1_750_000_000_000);
   });
 
-  it('advances at the idle real-time rate (IDLE_WORLD_TIME_SCALE) while grounded, not frozen (ISS-128)', () => {
+  it('stays exactly at the anchor value while grounded (frozen, #135)', () => {
     const a = anchor({ advancing: false });
-    expect(advanceSimClock(a, 1_000_000)).toBe(1_750_000_000_000); // zero elapsed — still the anchor value
-    expect(advanceSimClock(a, 1_001_000)).toBe(1_750_000_000_000 + 1_000 * IDLE_WORLD_TIME_SCALE); // a full second later — real time, not frozen
+    expect(advanceSimClock(a, 1_000_000)).toBe(1_750_000_000_000); // zero elapsed — the anchor value
+    expect(advanceSimClock(a, 1_001_000)).toBe(1_750_000_000_000); // a full second later — still frozen
   });
 
   it('clamps to the anchor value when nowMs is before the anchor (clock skew), never backwards', () => {
diff --git a/lib/useSimClock.ts b/lib/useSimClock.ts
index 6a782bb..a1d443c 100644
--- a/lib/useSimClock.ts
+++ b/lib/useSimClock.ts
@@ -2,16 +2,15 @@
 
 import { useEffect, useRef, useState } from 'react';
 import type { StateSnapshot } from './game/state';
-import { IDLE_WORLD_TIME_SCALE, WORLD_TIME_SCALE } from './worldClock';
+import { WORLD_TIME_SCALE } from './worldClock';
 
 // ISS-007 (v0.16.1): the sim clock ticks smoothly on the CLIENT between polls instead of
 // jumping once per snapshot. The server's authoritative rate is exactly real-time × scale
 // (tickOnce in lib/sim/engine.ts: advance = min(elapsed, MAX_TICK_ELAPSED_MS) × timeScale), so
 // client-side extrapolation mirrors the server's own model. Every new snapshot re-anchors to
 // server truth, bounding any drift by network latency only. ISS-117 (v0.52.0): the scale is the
-// fixed WORLD_TIME_SCALE; ISS-128 (v0.56.0): while nothing is happening it slows to
-// IDLE_WORLD_TIME_SCALE (real time) instead of freezing — mirroring the server's idle slowdown,
-// so polls re-anchor without a visible jump.
+// fixed WORLD_TIME_SCALE; #135 (v0.62.0): while nothing is happening it stays FROZEN at the anchor
+// value — mirroring the server's freeze, so polls re-anchor without any jump.
 
 export interface SimClockAnchor {
   // Server truth at anchor time — the snapshot's simState.clockMs.
@@ -23,11 +22,11 @@ export interface SimClockAnchor {
 }
 
 // Pure core of the extrapolation — mirrors tickOnce: while advancing, game time advances by
-// real-time × WORLD_TIME_SCALE; while idle it slows to real-time × IDLE_WORLD_TIME_SCALE (ISS-128).
+// real-time × WORLD_TIME_SCALE; while fully grounded it stays frozen at the anchor value (#135).
 // nowMs before `at` clamps to the anchor value instead of going backwards. Unit-testable in node.
 export function advanceSimClock(anchor: SimClockAnchor, nowMs: number): number {
-  const scale = anchor.advancing ? WORLD_TIME_SCALE : IDLE_WORLD_TIME_SCALE;
-  return anchor.clockMs + Math.max(0, nowMs - anchor.at) * scale;
+  if (!anchor.advancing) return anchor.clockMs; // frozen while everything is grounded (#135)
+  return anchor.clockMs + Math.max(0, nowMs - anchor.at) * WORLD_TIME_SCALE;
 }
 
 // ~10 fps display refresh — smooth for a seconds-precision wall clock without busy re-renders.
@@ -43,7 +42,7 @@ export function useSimClock(snapshot: StateSnapshot | null): number | null {
   useEffect(() => {
     if (!snapshot) return;
     // Mirror of the server's shouldAdvanceTime (lib/sim/engine.ts): full rate only while a plane
-    // is flying or in repair, idle real-time otherwise. One line on purpose — keep it in sync.
+    // is flying or in repair, frozen otherwise (#135). One line on purpose — keep it in sync.
     const advancing = snapshot.planes.some((p) => p.status === 'flying' || p.status === 'repairing');
     anchorRef.current = { clockMs: snapshot.simState.clockMs, at: Date.now(), advancing };
     setDisplayMs(advanceSimClock(anchorRef.current, Date.now()));
diff --git a/lib/worldClock.ts b/lib/worldClock.ts
index ed105b4..a72d2b3 100644
--- a/lib/worldClock.ts
+++ b/lib/worldClock.ts
@@ -3,7 +3,8 @@
 // lib/useSimClock.ts extrapolates between polls at this same constant, so keep them in sync here.
 export const WORLD_TIME_SCALE = 24;
 
-// ISS-128 (v0.56.0): a fully grounded fleet no longer freezes the world — it slows to real time
-// (one game-second per real second) so packages keep spawning/expiring and the market stays fresh.
-// Derived from the existing constant: WORLD_TIME_SCALE / 24 = 1, i.e. exactly "real-time".
-export const IDLE_WORLD_TIME_SCALE = WORLD_TIME_SCALE / 24;
+// #135 (v0.62.0): a fully grounded fleet FREEZES the world clock — shouldAdvanceTime
+// (lib/sim/engine.ts) gates every tick and advanceSimClock (lib/useSimClock.ts) holds its anchor
+// value, so polls re-anchor without any jump. This replaces the v0.56.0 idle slowdown
+// (IDLE_WORLD_TIME_SCALE = WORLD_TIME_SCALE / 24): final semantics are ISS-117's — frozen when
+// everything is grounded, full rate otherwise.
diff --git a/package.json b/package.json
index d9c7496..ff7f3cb 100644
--- a/package.json
+++ b/package.json
@@ -1,6 +1,6 @@
 {
   "name": "flight-ops",
-  "version": "0.61.0",
+  "version": "0.62.0",
   "private": true,
   "scripts": {
     "dev": "next dev -p 3000",