A few of my all time favorite pens for sketching are:
1. Fountain Pens are the best!!! Watersoluble ink makes a nice wash with a water brush. The line can also be varied with pressure and release.
2. Pigma Micron, size 01, by Sakura. Waterproof. Black and other colors 3. Tombow Zoom Pen. waterproof! I love this one. 4.Pentel Slicci. 5. Pilot Hi-Tec C for a fine line.
WAITING TO BOARD ALASKA AIRLINES for Seattle, Washington.
Airport waiting holds one of the best opportunities for sketching people and of course, planes.