FSX Spikes using SRTM

Trying out some Mesh using 1 arc second SRTM data and resample.

I'm not familiar with this process at all, so just need to know if these spikes are a problem I can fix, or just a case of "Garbage In, Garbage Out" - ie bad input data.

The data in Global Mapper 15 seems to have a lot of white patches, but I'm not sure what that means. Is that missing data?



Thanks folks, I've found some better data. Not the best but it will have to do as data for this part of the world seem rather scarce.

Now to figure out how to make these cliff faces look nice...