diff --git a/public/models/fleet/types.json b/public/models/fleet/types.json
index 3492f58c9..d0a62f091 100644
--- a/public/models/fleet/types.json
+++ b/public/models/fleet/types.json
@@ -1149,6 +1149,7 @@
     70,
     79
    ],
+   "typical_len": 300,
    "rules": [
     {
      "min_len": 70,
@@ -1188,6 +1189,7 @@
     80,
     89
    ],
+   "typical_len": 250,
    "rules": [
     {
      "name_re": "\\bLNG\\b|\\bGAS\\b",
@@ -1214,6 +1216,7 @@
     60,
     69
    ],
+   "typical_len": 140,
    "rules": [
     {
      "min_len": 70,
@@ -1243,6 +1246,7 @@
     37,
     37
    ],
+   "typical_len": 19,
    "rules": [
     {
      "min_len": 35,
@@ -1273,6 +1277,7 @@
     30,
     30
    ],
+   "typical_len": 24,
    "rules": [
     {
      "min_len": 15,
@@ -1343,6 +1348,7 @@
     55,
     55
    ],
+   "typical_len": 40,
    "rules": [
     {
      "min_len": 25,
@@ -1358,6 +1364,7 @@
     40,
     49
    ],
+   "typical_len": 40,
    "rules": [
     {
      "min_len": 20,
@@ -1373,6 +1380,7 @@
     33,
     33
    ],
+   "typical_len": 100,
    "rules": [
     {
      "min_len": 50,
diff --git a/src/data/fleetModels.js b/src/data/fleetModels.js
index 7c0204fdd..6a3749561 100644
--- a/src/data/fleetModels.js
+++ b/src/data/fleetModels.js
@@ -133,8 +133,9 @@ export function hullBeam(beam) {
 /**
  * The model for a vessel of AIS ship type `shipType` and the reported length
  * and beam (metres) and name: the first rule that matches in the first type
- * range that has one, else `default_vessel`. Drawn at the reported length, as
- * built when it is unknown.
+ * range that has one, else `default_vessel`. Drawn at the reported length;
+ * when it is unknown (most live feeds send none), chosen and drawn at the
+ * range's `typical_len`, else as built.
  * @param {object} types Parsed `types.json`.
  * @param {number} [shipType]
  * @param {number} [length]
@@ -145,13 +146,14 @@ export function hullBeam(beam) {
 export function resolveVessel(types, shipType, length, beam, name) {
   const L = hullLength(length) ?? 0;
   const B = hullBeam(beam) ?? 0;
-  const drawn = L > 0 ? L : null;
   if (shipType !== undefined && shipType !== null) {
     for (const group of types.vessels) {
       if (!(shipType >= group.types[0] && shipType <= group.types[1])) continue;
+      const len = L > 0 ? L : (group.typical_len ?? 0);
+      const drawn = len > 0 ? len : null;
       for (const rule of group.rules) {
-        if (rule.min_len && L < rule.min_len) continue;
-        if (rule.max_len && L > rule.max_len) continue;
+        if (rule.min_len && len < rule.min_len) continue;
+        if (rule.max_len && len > rule.max_len) continue;
         if (rule.name_re && !new RegExp(rule.name_re).test(name ?? ''))
           continue;
         if (rule.max_bl && !(B > 0 && L > 0 && B / L <= rule.max_bl)) continue;
@@ -159,7 +161,7 @@ export function resolveVessel(types, shipType, length, beam, name) {
       }
     }
   }
-  return { model: types.default_vessel, length: drawn };
+  return { model: types.default_vessel, length: L > 0 ? L : null };
 }
 
 /**
diff --git a/src/data/fleetModels.test.mjs b/src/data/fleetModels.test.mjs
index 9eb484a6a..f0387e65d 100644
--- a/src/data/fleetModels.test.mjs
+++ b/src/data/fleetModels.test.mjs
@@ -57,6 +57,7 @@ const sliceTypes = {
   vessels: [
     {
       types: [70, 79],
+      typical_len: 300,
       rules: [
         { min_len: 70, max_len: 140, max_bl: 0.12, model: 'inland_cargo' },
         {
@@ -133,6 +134,29 @@ test('vessels: the first matching rule of the first type range with one, else th
   });
 });
 
+test("vessels of unknown length are chosen and drawn at their range's typical length", () => {
+  assert.deepEqual(resolveVessel(sliceTypes, 70), {
+    model: 'container_ship',
+    length: 300,
+  });
+  assert.deepEqual(resolveVessel(sliceTypes, 70, 511, 126), {
+    model: 'container_ship',
+    length: 300,
+  });
+  assert.deepEqual(resolveVessel(sliceTypes, 70, 90, 15), {
+    model: 'general_cargo',
+    length: 90,
+  });
+  assert.deepEqual(resolveVessel(sliceTypes, 31), {
+    model: 'tug',
+    length: null,
+  });
+  // Every passenger, cargo and tanker range of the set has one.
+  for (const code of [60, 70, 80]) {
+    assert.ok(resolveVessel(types, code).length > 100, String(code));
+  }
+});
+
 test("vessels: AIS's out-of-range sizes (511 m long, 126 m abeam) are unknown, drawn as built", () => {
   assert.deepEqual(resolveVessel(sliceTypes, 52, 511), {
     model: 'tug',