diff --git a/html_ui/Pages/VCockpit/Instruments/Airliners/B747_8/FMC/B747_8_FMC_VNAVPage.js b/html_ui/Pages/VCockpit/Instruments/Airliners/B747_8/FMC/B747_8_FMC_VNAVPage.js
index 427f20ca7..735d295d6 100644
--- a/html_ui/Pages/VCockpit/Instruments/Airliners/B747_8/FMC/B747_8_FMC_VNAVPage.js
+++ b/html_ui/Pages/VCockpit/Instruments/Airliners/B747_8/FMC/B747_8_FMC_VNAVPage.js
@@ -89,11 +89,11 @@ class B747_8_FMC_VNAVPage {
             n1Cell = n1Value.toFixed(1) + "%";
         }
 
-        let weightIndex = SimVar.GetSimVarValue("TOTAL WEIGHT", "pounds") - 608000;
-        let maxFltLevel = 431
-        if (weightIndex >= 0){
-            maxFltLevel = 431 - (weightIndex / 362000 * 110)
-        }
+        //Calculate maximum Flight level - uses linear regression derived formula from actual aircraft data
+        let currentWeight = SimVar.GetSimVarValue("TOTAL WEIGHT", "pounds");
+        let weightLimitedFltLevel = (((-0.02809 * currentWeight) + 56571.91142) / 100);
+        let maxFltLevel = Math.min(431, weightLimitedFltLevel);
+        
         fmc.setTemplate([
             [crzPageTitle, "2", "3"],
             ["CRZ ALT", "STEP TO"],