diff --git a/common/src/main/kotlin/org/valkyrienskies/clockwork/ClockworkConfig.kt b/common/src/main/kotlin/org/valkyrienskies/clockwork/ClockworkConfig.kt
index 07814181d..9b17458d7 100644
--- a/common/src/main/kotlin/org/valkyrienskies/clockwork/ClockworkConfig.kt
+++ b/common/src/main/kotlin/org/valkyrienskies/clockwork/ClockworkConfig.kt
@@ -100,6 +100,9 @@ object ClockworkConfig {
         @ConfigEntry(description = "The maximum surface area (in blocks) that the hot air balloon floodfill will scan when trying to determine the balloon's exterior.", min = 1.0)
         var hotAirBalloonMaxScanSurface = 100000.0
 
+        @ConfigEntry(description = "Display invalid non-air blocks when doing a hot air balloon floodfill.")
+        var hotAirBalloonDebugInvalidBlocks = false
+
         @ConfigEntry(description = "Force multiplier when no rpm is given")
         var angleFollowingBaseAngleErrorMultiplier = 50.0
 
diff --git a/common/src/main/kotlin/org/valkyrienskies/clockwork/content/forces/BalloonController.kt b/common/src/main/kotlin/org/valkyrienskies/clockwork/content/forces/BalloonController.kt
index d11572e4e..3488e6657 100644
--- a/common/src/main/kotlin/org/valkyrienskies/clockwork/content/forces/BalloonController.kt
+++ b/common/src/main/kotlin/org/valkyrienskies/clockwork/content/forces/BalloonController.kt
@@ -23,6 +23,7 @@ import org.valkyrienskies.clockwork.content.forces.data.BalloonData
 import org.valkyrienskies.clockwork.content.forces.data.BalloonData.PhysBalloonData
 import org.valkyrienskies.clockwork.util.AABBHelper.mergeAdjacentFast
 import org.valkyrienskies.clockwork.util.AerodynamicUtils.dimensionMap
+import org.valkyrienskies.clockwork.util.DebugOutputUtil.indicatePositionToNearbyPlayers
 import org.valkyrienskies.core.api.VsBeta
 import org.valkyrienskies.core.api.attachment.getAttachment
 import org.valkyrienskies.core.api.ships.LoadedServerShip
@@ -358,7 +359,9 @@ class BalloonController: ShipPhysicsListener {
 
             for (dir in Direction.values()) {
                 val n = cur.relative(dir)
-                if (level.getBlockState(n).isValidBalloonEnclosure(level, n)) continue
+                val bs = level.getBlockState(n)
+                if (bs.isValidBalloonEnclosure(level, n))
+                    continue
                 val nl = n.asLong()
                 if (!visited.contains(nl)) q.add(nl)
             }
@@ -389,12 +392,21 @@ class BalloonController: ShipPhysicsListener {
 
         @JvmStatic
         fun BlockState.isValidBalloonEnclosure(level: Level, pos: BlockPos): Boolean {
-            return !this.isAir && this.isCollisionShapeFullBlock(level, pos)
+            if (this.isAir) return false
+            if (this.isCollisionShapeFullBlock(level, pos)) return true
+            // For debugging non-trivial failures when building balloon enclosures (non-full blocks)
+            if (ClockworkConfig.SERVER.hotAirBalloonDebugInvalidBlocks)
+                indicatePositionToNearbyPlayers(level, pos.center, "debug.invalid_balloon_enclosure", pos)
+            return false
         }
 
         @JvmStatic
         fun BlockState.isValidBalloonEnclosureDirectional(level: Level, pos: BlockPos, direction: Direction): Boolean {
-            return !this.isAir && !this.isFaceSturdy(level, pos, direction.opposite)
+            if (this.isAir) return false
+            if (this.isFaceSturdy(level, pos, direction.opposite)) return true
+            if (ClockworkConfig.SERVER.hotAirBalloonDebugInvalidBlocks)
+                indicatePositionToNearbyPlayers(level, pos.center, "debug.invalid_balloon_enclosure_directional", direction, pos)
+            return false
         }
     }
 }
diff --git a/common/src/main/kotlin/org/valkyrienskies/clockwork/util/DebugOutputUtil.kt b/common/src/main/kotlin/org/valkyrienskies/clockwork/util/DebugOutputUtil.kt
new file mode 100644
index 000000000..f2d384a8c
--- /dev/null
+++ b/common/src/main/kotlin/org/valkyrienskies/clockwork/util/DebugOutputUtil.kt
@@ -0,0 +1,26 @@
+package org.valkyrienskies.clockwork.util
+
+import net.minecraft.client.multiplayer.ClientLevel
+import net.minecraft.core.particles.ParticleTypes
+import net.minecraft.server.level.ServerLevel
+import net.minecraft.world.level.Level
+import net.minecraft.world.phys.Vec3
+import org.valkyrienskies.clockwork.ClockworkLang
+
+object DebugOutputUtil {
+    fun indicatePositionToNearbyPlayers(level: Level, pos: Vec3, langKey: String?, vararg args: Any) {
+        val particleType = ParticleTypes.END_ROD
+        val particleCount = 20
+
+        val player = level.getNearestPlayer(pos.x, pos.y, pos.z, 256.0, false)
+        if (langKey != null) player?.displayClientMessage(ClockworkLang.translate(langKey, *args).component(), false)
+        if (level is ServerLevel)
+            level.sendParticles(
+                particleType,
+                pos.x, pos.y, pos.z,
+                particleCount, 0.3, 0.3, 0.3, 0.0
+            )
+        else if (level is ClientLevel)
+            repeat(particleCount) { level.addParticle(particleType, pos.x, pos.y, pos.z, 0.0, 0.0, 0.0) }
+    }
+}
\ No newline at end of file
diff --git a/common/src/main/resources/assets/vs_clockwork/lang/en_us.json b/common/src/main/resources/assets/vs_clockwork/lang/en_us.json
index 76e34b4ba..af8ae2e19 100644
--- a/common/src/main/resources/assets/vs_clockwork/lang/en_us.json
+++ b/common/src/main/resources/assets/vs_clockwork/lang/en_us.json
@@ -464,5 +464,8 @@
   "vs_clockwork.ponder.solid_delivery.text_9": "and belts",
 
   "death.attack.gas_burn": "%s was singed to a crisp",
-  "death.attack.gas_explosion": "%s couldn't handle the pressure"
+  "death.attack.gas_explosion": "%s couldn't handle the pressure",
+
+  "vs_clockwork.debug.invalid_balloon_enclosure": "Invalid balloon block: %s",
+  "vs_clockwork.debug.invalid_balloon_enclosure_direction": "Invalid balloon block for direction %s: %s"
 }