Article in 'Government Computer News' about the NGS and benchmarks...

[+mikeb226]

http://gcn.com/Articles/2010/07/12/Geodeti...aps.aspx?Page=1

[+tech22]

The article makes it sound to me like no one will be paying attention to the benchmark updates any longer...

[AZcachemeister]

Indeed, increasing GPS accuracy is making the passive marks less and less necessary.

I doubt there will be a time when they are completely useless, however.

And if something should happen to the GPS satellites...

[Bill93]

Horizontal (e.g. triangulation station) marks are still sometimes useful but not as necessary as they once were before GPS.

 

True (elevation) benchmarks are still required for many purposes because GPS (ellipsoid) height is not the same kind of (orthometric) elevation needed for real-world work. It will be another 8-10 years according to the GRAV-D plan before they have enough gravity data to let GPS data be converted to orthometric at the accuracy required for many purposes.

[Bill93]

GRAV-D is happening. Some professional surveyors got a tour of the plane, as discussed here: http://surveyorconnect.com/index.php?mode=thread&id=49335

 

They give a link to the spec sheet on the instrument or one very similar.

Edited February 6, 2011 by Bill93