Leech: About the design?
Hall: It wasn’t a very stable airplane. Lindbergh wanted it unstable so he’d stay awake. Notice the ailerons are very small. I did that purposely. I was worried that with a full load and sudden gusts, the wing might have structural failure. It lost some weight. I was very satisfied when I was through. The main job was to get good flight data in the limited time we had.
We had more than the usual instrumentation. We had an earth inductor compass and a magnetic compass. The earth inductor wasn’t working too well and failed in flight.
Leech: What was your first reaction to Lindbergh’s planning to fly alone?
Hall: It surprised us but right away we saw the merit. With two people, you need a much larger airplane. One advantage is that one person could rest while the other was flying. Lindbergh felt confident he could do it solo. I wasn’t worried a bit.
Leech: Did Ryan add any engineers?
Hall: I was all alone during the design of the plane, except for two evenings when a purchasing agent helped me with weight analysis. We kept the office door locked so nobody could walk in. A few aeronautical people were always interested in anything and they’d walk around; we didn’t keep anything from them. I don’t think we talked about it but gradually it leaked out. When test flights started, people in San Diego heard about it.
Leech: Where did you make the test flights?
Hall: We flew from Dutch Flats, just opposite from Marine Corps Recruit Depot. Dutch Flats was a tidal flat at one time. I think they built up a dike so water wouldn’t flow in. It was not paved; it was a natural tidal ground with sand and muck. When it rained heavily you might have two to three feet of water.
Just before Lindbergh got here, we had heavy rains and floods for two weeks. You couldn’t leave San Diego except by way of El Centro. Lindbergh came by train about a week later.