NOAA Teacher at Sea
Aboard NOAA Ship Okeanos Explorer
March 16-April 3rd
Mission: Caribbean Exploration (Mapping)
Geographical Area of Cruise: Puerto Rico Trench
Date: April 1, 2015
Weather Data from the Bridge: Partly Cloudy, 26˚C, waves 1-3ft, swells 3-6ft.
Science and Technology Log:
Dr. Wilford (Bill) Schmidt has demonstrated the saying, “Where there is a will, there is a way,” throughout this entire cruise. He knew this voyage would put his new free vehicle design to the test and he came prepared to modify this, tweak that, collaborate with the crew, confer with his university team, test, and repeat. He is an engineer and that is the name of the game.
1. The first deployment looked great. The vehicle reached 1000m. The magnetometer and 3-axis accelerometer worked great. All systems were a go. A water sampling device was used as a dummy payload.
Crossing fingers for more success.
2. The next step was to attach a CTD (a probe that measures Conductivity, Temperature, Depth). The deployment and retrieval process again went smoothly, this time to 2126m, but there was a problem retrieving the log file from the bottom sphere and one of the anchor burn wires did not burn.
Collaboration required with folks on shore and the electronics technicians on this ship. Tweak this, fix that.
Bill opened the spheres to change the batteries for the satellite transponder.
All systems were a go again.
3. The crew deployed the free vehicle with the CTD to 4679 m. It took a little longer to find and retrieve the vehicle.
The data files indicated that the galvanic releases released the anchor prematurely, at about 100 meters from the bottom. Both spheres worked during the mission. Data files were retrieved from each. During inspection water was found in the bottom sphere. Spalling of the glass (flaking) was seen on the inside. The leak is assumed to have taken place as the surface under low pressure conditions, otherwise the damage would have been worse. The electronics were in good shape but the bottom sphere had to be retired.
Oh no! Is that the end? Not when you have great minds on board!
This is where engineering in the ocean environment gets tricky. Bill can’t just head back to the university and make the necessary repairs. Instead he needs to make use of the very valuable ship time by pinch-hitting. Bill recalculated the buoyant force on the vehicle with only one sphere. It might just work!
Tweak this, lighten that, new attachments there. Ready for a float test!
Will the single sphere allow it to ascend from the bottom fast enough for us to deploy and retrieve it during our mission? That question required further testing. So the crew planned to lower it into the water a short distance with the winch and allow it to float back up. The weather would not allow it. The seas were too rough to allow the ship to stay in one place during the vehicle test without dragging the free vehicle thereby negating the results of the test.
Plan B? The operations team hatched a plan to tie the free vehicle to buoys on a long rope. That allowed the vehicle to sink and be recovered easily if it rose too slowly. First a buoyancy test had to be done to make sure the buoys wouldn’t sink with the vehicle.
The vehicle rose in less than 10 minutes so the team was back on track! With a few extras like flags for better visibility, the vehicle was ready to dive!
4. The deployment into the trench went smoothly. The crew had that routine down pat. After 10 hours it was time for the retrieval. Everyone gathered at the bridge to try to spot it.
It successfully collected data down to the bottom at 8379m, a possible record for a free vehicle!
The CTD data was processed and looked great during the descent.
Inspection of the data log showed that while the vehicle was ascending from the bottom, something was triggering a mission cancel order – 28 times! This bug required more testing and mission simulating before another deployment in the trench. Just after 8pm, Bill announced his equipment was ready to go for a 6 am deployment the next day.
5. The next day, the retrieval took a bit longer due to choppier sea conditions.
Again the vehicle logs showed “cancel mission” messages during the ascent. It is confounding Bill and his team back home, because during mission simulations the mission goes to completion without a problem.
In all the voyage has been very constructive for Bill’s engineering team. They successfully deployed the vehicle to the bottom of the Puerto Rico Trench known to be the deepest part of the Atlantic Ocean. That is something to celebrate! They have learned a great deal about what types of modifications they should make to improve the retrieval process.
This was a great first test of the free vehicle design. The next time out at sea will come soon enough and Bill’s team will be ready!
As the voyage comes to an end and we travel nearer to shore, I am filled with mixed emotions. I will miss the ocean, the feeling of being a part of an exploration expedition, and these people. I am also very happy to be going home to my family and my students. I am looking forward to sharing what I have learned. I will be looking for partnerships to help get students involved in reseach on our inland sea, Lake Superior. If you have any suggestions, please leave a comment below!
Exciting moments? Seeing these creatures!
Other great moments include driving the ship and making video fly-bys of the ocean floor with the bathymetry and backscatter data. Very awesome! The videos will be coming soon so stay tuned!
Did you know?
Do you remember the flying fish I wondered about a few blogs ago? I have never seen them before. At first I thought I was seeing things. I thought I saw a very large dragonfly dive into the water. Then I saw more. – schools of them jumping away from the boat all at once. In a blink of an eye they were gone.
According to Wikipedia, there are 64 species of flying fish! They fly out of the water to evade predators. That’s a pretty cool adaptation! You can learn more here.
Question of the Day: