A week on the road

A couple months ago, I proposed a new device to a customer, and they agreed. This week I helped to install and test it. It is a system to measure the thrust of an installed engine. That task is normally reserved for a test cell. This particular customer has no traditional test cell, but is doing heavy enough maintenance on his engines that a more in-depth test of the engine's performance may be warranted, at least according to some folks in the government. Anyway, the theory behind the system is based on using a strain gage instead of a load cell. There is a slight decrease in accuracy compared to a load cell, but it is still within reasonable limits of a half percent or less. There is a tremendous difference in cost between the system I designed versus a traditional brick & mortar test cell, which can run as high as $30M.

Anyway, we installed the system and did several tests with an engine that was run in a calibrated test cell. So we know that engine's performance characteristics. Now I am trying to make sure what we measured with the new system is accurately reflecting how the engine is running. It was pretty neat being in the cockpit of that aircraft, a B747, and watching the thrust readout change as the throttles were moved around. Sometimes its fun to be an engineer!