It is easy to get wrapped up in the flying aspect of flight testing when taking an airplane through phase 1. We preflight, then launch into sawtooth climbs, stall series, and determine Vx and Vy. But it's important to keep an overall eye on the mechanical aspects of the airframe as well. This is what I found when I climbed up on the wing of our Tundra this morning to add some fuel - a whole bunch of missing PK screws that hold the fuel tank cover plate in place on the left side.
This was obviously a STOP!
It appears in this case that maybe the wrong size screws were installed, or maybe they just weren't tightened fully when it was assembled as part of the factory assist program about ten years ago. Easy to fix of course - just install a bunch of new screws. But a good example of how thorough the preflight needs to be for each test mission. I'm pretty sure they were there when we launched this morning - I looked at all the surfaces. But it's not a bad idea to go over the plane with a screwdriver, just like inspecting an engine compartment with a couple of wrenches in your hand to check fitting tightness.
Fix, fly - repeat.