The Echo returned us to the Strong this morning.  The sun was shining and there was a slight breeze.  We deployed the seismic equipment and began work shortly after 8 AM.  Probably two hours into the acquisition, we stopped.  During the previous day, the compressor that builds up the air pressure (2000 psi) for the seismic energy source started to emit a rattling noise.  Humans can squeeze ~100-150 psi with their fists; a female Great Horned owl with one talon is 1000 psi…just for trivia's sake.  We believe a ball bearing was going out.  Not good.

We had enough air stored up in our tanks to acquire thirty more minutes of data while we assessed options.  The options were to find a compressor locally that we could rent, fly overnight a new pump assembly from Texas, or have the man who designed the compressor drive us up a new assembly and help us install it.  People don’t rent compressors at such high pressures.  Flying a new pump in would be expensive, and we would not have the designer.  Andrew Day designed and built the compressor we are using.  He was willing to drive us up a new pump assembly from his company, Max-Air, in Kerrville, TX, and help us install it.

The latter option was the best option.  Andrew and his son, Josh, would make the long 15-hour drive from Kerrville, TX, to Caruthersville, MO, to save the project, but we still had a problem.  We would be down for at least two days.  We were scheduled to complete our survey June 21.  This delay due to the compressor would force us to extend our trip to June 23.  The seismic equipment we are using has to be in Seattle, WA, by June 25, for another survey team.  With the US Army Corps of Engineers offering to continue hosting us onboard the Strong until June 23, we were still hampered by the shortened window to ship the equipment to Seattle.

A call was made to Federal Express.  We desperately needed their help.

We retired to our hotel in Dyersburg to work out logistics and catch up on university work: emails, research proposals, publications, and so forth.