Steering problems on turbojet hydroplane

[FranklinRatliff]

"Craig [Arfons]told me the boat lacked steering authority and wanted to go in the direction centrifugal force (Spinning turbine)wanted to go.-
The good run he made was lining up off to one side and the boat barely making it between the top end markers----AND this was before the AB [afterburner]."

http://www.users.myisp.co.uk/~climen...d/coniston.htm

In the above link (photo) of Donald Campbell's Bluebird you can see how there was a planing shoe instead of a skeg under the middle of the stern with the rudder located to the left of the shoe and a fixed fin located to the right (I think the fixed fin was a later addition). Campbell's boat with the Orpheus engine weighed about 2,000 lbs more than the Craig Arfons boat and had about the same thrust, but had no problems in running on a lake only a little longer than the one Craig used.

You know how you can look at something over and over and suddenly see details you've been missing?

I was looking over photos I took of Craig's boat and noticed how the rudder set-up was designed not only to be very strong but to evenly distribute the loads so that no one part of the boat such as the transom was overloaded. I think now that was the root cause of Craig's problems with being unable to hold the boat on course.

The rudder on Craig's boat was a short blade bolted inside a pillow block with the pillow block pivoted at the top on a bracket just underneath the drag chute anchor and at the bottom on a bracket halfway down the trailing edge of the skeg. The bracket on the skeg was further supported by a channel or angle iron bolted to each side of the skeg with the iron angled upwards, paralleling the bottom edge of the skeg. The rudder extended maybe half a foot deeper than the skeg. It seems possible to me Craig's rudder was either in a turbulent wake or a hole in the water.

http://www.lesliefield.com/personali...d_a_prayer.htm