Author: admin (Page 13 of 36)

Hey All!

As of 2pm Ascension time, RU 29: Challenger is back on her feet sailing off towards the horizon!

Over the next day or so we will fly her to the north as to avoid any unfavorable bathymetry that lies to our west, but soon we will move our way point in the direction of Brazil as we set our sight on the shores of South America!

Force Wind Sea & Honor

Hey All,

It has been a long couple of days for the crew down in Ascension since their arrival.  After giving Challenger a thorough inspection of the kind of growth on the hulls and the corrosion that occurred over the course of the previous 288 day mission, they set to work on getting her ready to get back in the water and set sail towards Brazil.

Among a number of tasks to be done before re deploying Challenger and sending her on her way are:

1. Inspect for corrosion (on end caps), damage, plugged pressure sensors, document any damage with pictures so we have them for the future. Take note of fouled locations if you can, otherwise we can use Jame’s pictures from Helena.
2. Inspect internally for leak, salt, corrosion. Pitch threads. Take off and clean nose cone and buoyancy pump diaphragm.
3. Check compass!!!
4. Check digifin operation with different ranges specified.
5. Scrub glider down, perhaps lightly on the painted sections, remove old bio films.
6. Open glider, backup flash cards in 2 locations, Format cards, Upgrade to software 7.13
7. Re-battery, compare battery weights on labels, do best to account for that with bottles, etc. Glider was about 40 g lighter than average density, which I think was good, wouldn’t want to go too much outside of 50 g too light/heavy. I think goal is to maybe leave it a tad light with 2 wing rail weights. Tape and paint will add some weight and we can use wing rail weights to add the rest… We were ballasted pretty-much perfect so if were close to where we were before that is our best bet. Our best check may be a ballast dunk at the dock.
8. Replace digifin?
9. Re-seal for deployment, new o-rings
10. Apply new antifoul items, paint, tape…
11. Re-cal compass

At the base that was used for technical support, Drew Avery, an ex-navy diver from Greenland who now works at the local US base lent his steady hand to perform the “open heart surgery” that was required to set 29 up to get back in the water.

Once Challenger was put all back together, the team put her in the back of the pick up and drove her down to the beach where they then used a tidal pool that was separated from the open ocean by low tide as a ballast tank.

In this pool they were then able to trim the ballast on the glider until they were certain she was ready to continue her trek towards Sao Paulo.

Next up is the deployment- stay tuned!

Force Wind Sea & Honor

Hey All,

To add stress to our plans for repair and redeployment operations in such a remote place as Ascension Island, the plane that is to carry Chuck Chip and Scott to the island was delayed on its return from the Faulkland Islands.  The team now plans to arrive on the island between the 5-6 of November to work on Challenger

More details to come soon

Force Wind Sea & Honor

Hey All!

This afternoon, Collin took his ship out of George Town, Ascension Island and carried out a successful recovery of RU29: Challenger!

He sailed out about 25 nm to where he found Challenger drifting at the surface, covered in the eggs of Flying Fish

Now back on shore, Challenger will remain on station until Nov 4th when Chip Chuck and Scott will arrive on the island to replace the batteries, make the necessary repairs and redeploy.  From there she will continue on to Brazil to complete her crossing of the south Atlantic

Force Wind Sea & Honor

Hey All

So we seem to have run into some trouble over the past day.  Challenger has had a sudden drop in voltage which we have come to find is associated with the lithium batteries being dangerously low on juice.

Challenger is now up at the surface drifting as we do not want to test how much remaining battery we have left.  We have been in contact with Collin out on the island to see if he is available for an emergency recovery.

Looking to PINZON’s forecast of the currents, it is dire that we get this glider out of the water soon, as it looks like the overall flow will be away from the island over the forecasted period, pushing us out of the recovery zone

We will keep you updated on the details of the recvoery, but for now here is some of the data we collected during our sampling missions.  It will be a much more complete data set once we recover and get the full files, but for now we can continue to see the oscillation up and down of the thermocline that we were hoping to capture.

Force Wind Sea & Honor

Hey All

Once again Challenger is making great time on her approach towards the recovery location.

Unfortunately, she may even be coming in too fast; so much so that Antonio and I have devised another sampling scheme to attempt over the next 10 or so days until our recovery team will be in place.  The plan we came up with is actually a relic from Silbo’s second mission, flying from the Azores to the Canaries back in the spring of 2012.

The plan we have come up with is to take Challenger and run a sampling mission through the eddy present within the lea of the island. As seen in the first image of this post, we will fly a “wind mill pattern” within the 35 nm recovery range over the course of the next week that will land us within 20 nm of the port we are to be recovered from by the first of November. From there, we will make slow progress towards the port by Nov 4th when we plan to finally get 29 out of the water, fix her up, and send her way ward back towards Brazil

Force Wind Sea & Honor

Hey All

Challenger has made it as far lateral as we wished to go!

Now we have placed her way point to the south east and will be making our final approach towards the island.  Although her progress was slowed by the currents running to the east-north east over the past week, she will still be arriving to the recovery zone well ahead of schedule. Antonio and I have been bouncing some ideas back and forth for ways to kill the next few weeks as we wait for Scott, Chip and Chuck to arrive on Ascension to recover and one of the most promising ideas may in fact be something out of the past. Check back in in a few days to see what we are cooking up!

Force Wind Sea & Honor

Hey All

As the recovery date looms nearer, Challenger continues to make head way parallel with the Ascension Fracture as we position ourselves for the final approach to the recovery location.  As previously discussed, Collin on Ascension Island told us that his boat which will be our vessel for recovery has a range of 40 nautical miles and that we should park ourselves to the west of the island within the lea.  From this information, I created the green polygon visible in the image above to set as our end zone as we prepare to wait out the arrival of our team that will be present for recovery.

Looking to pinzon, the sub surface current (>200m) continues to flow to the east, slowing us to roughly 22 km/day.  Even at these speeds, we should arrive within the recovery area well before our planned operation for Nov 4.  Until then, we shall continue forcing our way in the right direction as we come up with a constructive way to kill time until the recovery just under a month away

Force Wind Sea & Honor

Hey All,

So over the past week, we have continued to follow the sampling mission described last time: zig zagging our way over the portion of the Mid Atlantic Ridge called the Ascension Fracture as we make the final push to Ascension Island.

As predicted by Antonio, the currents have shown evidence of a rotation on either side of the ridge, clockwise to the south and counter to the north of the fracture

Another surprise we encountered while crossing over the rift was that on the first crossing, the glider reset underwater once again early on a weekend morning.  Unfortunately with these resets, we lose the data from the segment since it was written to the gliders RAM and not saved to the hard drive until the segment is complete.

Then later when we crossed the ridge again, we noticed that as we crossed, the compass began to spin close to when the glider should have been crossing over what is the thinnest part of the earths crust along the ridge, which may have caused a magnetic anomaly that led to the compass freaking out. A strong magnetic field we think could have caused the reset on the first crossing if it was strong enough

However on the third crossing, there doesn’t seem to be much of a reaction as the glider neither reset nor had too much of a wonky compass.

As the glider has been out for just under 9 months, the data on our pages has gotten very congested and so John Kerfoot has helped us out creating a new plot of the recent sampling mission, however, the data is a bit spread out for now so we can not make out any patterns just yet.  Looking at the old plot however, we can see the continued oscillation of the thermocline, although it has become much smaller than it was weeks ago.

Finally, as we are nearly ready to head west towards the island with a month still left before the planned recovery, Antonio and I have proposed to the group that we will fly the windmill pattern within the 40 mile box to the west of the island, which will keep us in range of the boat just in case anything bad happens.

Force Wind Sea & Honor

Hey all!

After this week, we are well underway into our sampling mission above the Ascension Fracture Zone.

With the sampling strategy we have laid out in the previous entry, we will be running a pretty close zig zag pattern over the ridge before running parallel to the north of the island.  With how tight the weaving pattern is, we have outlined the way points we will be pursuing over the upcoming days.

With how quickly we are making our way through this pattern, Antonio and I have been bouncing ideas off of each other just in case we have more time to kill. One idea we have arrived at includes flying a windmill pattern through a possibly eddy in the vicinity of the recovery zone

Force Wind Sea & Honor