Final Two Open Water Dives off Tower 20

I got to the beach just before 5:00 am and I was the first car there.  I parked in the former handicap zone.  Luis arrived at 7:30 am and found a place to park two cars from me.  The guys came at around 8:00 am and there were no spaces available.  They parked over by the Pelican and walked back.

First dive was their third open water dive, which means we had a long surface swim to the Eastern Ledge to make those ascents. It took us awhile to gear up, but we finally got in the water. Took probably 20 minutes to make the Ledge, but I think of this as time well spent.  I get to see that they really can keep themselves afloat should there be a problem and I don't have to worry about DCS since they really have no nitrogen load to speak of when we make the ascents. We all descended. Luis held the flag line while I led the guys through the two ascents: an alternative air source ascent and the Controlled Emergency Swimming Ascent. Both of them did fine. I got concerned because my Suunto was giving me ascent rate warnings, but once I saw the profile graph, I realized what I knew but had not remembered: that Suunto uses a 30 ft/minute ascent rate while PADI's is a much quicker 60 ft/minute. Then we swam back. Luis took pictures and the guys and I just looked on. Dive Time was 80 minutes; actual consumption was 25.16 psi/minute at an average depth of 17 feet; SAC rate was 16.61 psi/minute; and the RVM was 0.43 ft3/minute.

We were supposed to go over the problems during the surface interval, but the student who did not bring his problems yesterday failed to bring them today, as well. We worked through the first 4 problems, including finding the appropriate surface intervals in two dives on problem 3 and one dive on problem 4, then they advised me that I had not given them a formula for determining the appropriate surface interval. I lost it. So we gave up on the tables and made their fourth open water dive on the Ledge of Turtles. Swam right to the Rock Pile and descended, then headed up the reef at 120 degrees. Spotted the 3 little green mountainous coral heads just before the Big Rock and swam from there to the Ledge of Turtles. Luis took pictures. The guys and I just hung around looking. We spent about 50 minutes on the Ledge then swam to Shark's Rock and Sharks Rocks East, then we returned to the Ledge of Turtles just to touch base before heading to the beach.  Swam right to the Rock Pile and then to the beach.  Nice dive.  Dive Time was 97 minutes; Actual consumption was 23.24 psi/minute at an average depth of 15 feet; SAC rate was 15.98 psi/minute; RMV was 0.41 ft3/minute.