Any ideas why this is happening?

[Virgil UK]

Could it be that Blade is losing nominals somehow and has nothing to attach the measured value to?

Using Version 5.2 Bladerunner and 3.1 Blade.

[Pat Ahern]

That shape may not be "airfoily" enough. When I (Blade) have trouble with wierd looking data, I double check what the mean line looks like. If it's smooth and continuous, then I'd say it's the vectors (actuals or nominals???). If the mean line is loopy/spiraly or just not smooth, then I'd say it was Blade. I had to send some files to Hex about an airfoil section that had crazy spirals, figure 8s, etc for a mean line. They said the shape wasn't recognized as an airfoil by Blade. They made some adjustment ???? and sent me new Blade software that saw the shape as an airfoil. That fixed it.

[Virgil UK]

Thanks, I'll check the mean line but this program has worked fine before.