Allyn-Grapeview

This is the first of a series of zig zags to get by Seattle and stay below clouds while not hitting all the pointy mountains and structures sticking up.

The forecast had predicted 2000 ft ceiling in the area during my time of transit. In reality it got down to 800 ft. And that's avoiding the frequent saggy bottomed clouds. Relied on my moving map gps systems with vertical terrain profile to weave through. It never got troublesome although required considerable weaving. Followed inlets a lot since they were at sea level. Managed to stay clear of the plethora of restricted flying areas too.

Maybe this is why the controller in Portland wondered if I had a gps map system.

To extract precise zig zag information I used the aircraft's 'black box' data they are record at one second intervals.Read more