diff --git a/libraries/AP_InternalError/AP_InternalError.cpp b/libraries/AP_InternalError/AP_InternalError.cpp
index 1d08adaf64..0c61d7b8ad 100644
--- a/libraries/AP_InternalError/AP_InternalError.cpp
+++ b/libraries/AP_InternalError/AP_InternalError.cpp
@@ -37,7 +37,7 @@ void AP_InternalError::errors_as_string(uint8_t *buffer, const uint16_t len) con
         "write_mssfmt",  // logger_logwrite_missingfmt
         "many_deletes",  // logger_too_many_deletions
         "bad_getfile",  // logger_bad_getfilename
-        "unused1",
+        "panic",
         "flush_no_sem",  // logger_flushing_without_sem
         "bad_curr_blk",  // logger_bad_current_block
         "blkcnt_bad",  // logger_blockcount_mismatch
diff --git a/libraries/AP_InternalError/AP_InternalError.h b/libraries/AP_InternalError/AP_InternalError.h
index 0c6ee9102c..c489f885c8 100644
--- a/libraries/AP_InternalError/AP_InternalError.h
+++ b/libraries/AP_InternalError/AP_InternalError.h
@@ -42,7 +42,7 @@ public:
         logger_logwrite_missingfmt  = (1U <<  2),  // 0x00004  4
         logger_too_many_deletions   = (1U <<  3),  // 0x00008  8
         logger_bad_getfilename      = (1U <<  4),  // 0x00010  16
-        unused1                     = (1U <<  5),  // 0x00020  32
+        panic                       = (1U <<  5),  // 0x00020  32
         logger_flushing_without_sem = (1U <<  6),  // 0x00040  64
         logger_bad_current_block    = (1U <<  7),  // 0x00080  128
         logger_blockcount_mismatch  = (1U <<  8),  // 0x00100  256