diff --git a/years/1986/logbook.html b/years/1986/logbook.html
index 995d58cb0..b6695a6cf 100644
--- a/years/1986/logbook.html
+++ b/years/1986/logbook.html
@@ -20,7 +20,7 @@ Arrival statement.
 
 <hr />
 
-<div class="tripdate" id="1986_s01">1986-07-27</div>
+<div class="tripdate" id="1986-07-27a">1986-07-27</div>
 <div class="trippeople">Fred Smartarse, <u>Dave Smartarse</u>, </div>
 <div class="triptitle">123  - 123 Wave 1</div>
 
@@ -30,7 +30,7 @@ Tuesday David &amp; Fred Smartarse rig first section of new pitches. Second wave
 
 <hr />
 
-<div class="tripdate" id="1986_xyz">1986-07-27</div>
+<div class="tripdate" id="1986-07-27b">1986-07-27</div>
 <div class="trippeople">Mike W., Kurt Keinnamen, <u>Phil Tosser</u>, </div>
 <div class="triptitle">123  - wave 2</div>
 
@@ -39,7 +39,7 @@ A good trip for dropping tackle. German caver Kurt (non-expo) along for the trip
 
 <hr />
 
-<div class="tripdate" id="1986_12">1986-07-31</div>
+<div class="tripdate" id="1986-07-31a">1986-07-31</div>
 <div class="trippeople"><u>Mike Wideboy</u></div>
 <div class="triptitle">surface  - stupour</div>
 
@@ -47,7 +47,7 @@ A trip with no time-underground field present.
 
 <hr />
 
-<div class="tripdate" id="1986_13">1986-08-01</div>
+<div class="tripdate" id="1986-08-01a">1986-08-01</div>
 <div class="trippeople">Mike Wideboy</div>
 <div class="triptitle">123  - terminal</div>