Hey All,

So after a few more tweaks to our flight parameters, Dave has been able to get Challenger flying well again.  The issue we had run into over the past few days that had us worried was that the gains we had flown with before the reset were no longer working as we had planned to make the glider fly to our ideal standards.  However, after analyzing the data from our test dives and applying some adjustments, Dave was able to smooth out our flying and get us to a stabilized flight path.

Plot of Challenger’s heading error from Wednesday May 29 before the applied fixes

Plot of Challenger’s heading error after the applied fixes

In the first image, we had been able to get Challenger to fly well at full throttle, but when we tried and slow down to save some energy, our heading error went off the charts.  Looking into this, Dave concluded that there is something going on with the steering and vertical velocity when we fly at slower speeds.  In the mean time while we work to try and fix this issue, we will continue to fly fast which looks much better as shown in the second image.

Although we now have a glider that is proving to fly well through the water, our batteries took a hefty toll to get us to this point.  During the period of the siesta in which we had no communications with Challenger for 10 days from May 15-25, the glider flew within just the few meters of the surface, causing the pump to move in and out constantly.  Being that the pump is one of the most energy draining parts of glider, this continuous activity siphoned off a decent amount of the battery life, leaving us with just 176 days remaining.

An outline of the area from Challenger to Ascension Island

With an understanding of our energy budget and using an estimate that we can fly 15 km / day, that puts us at about 110 days of flying until we reach Ascension, with a 66 day cushion to help us deal with unfavorable currents and the logistics of getting a team out there for a recovery and re battery mission.

Navigation however has been difficult since the siesta as there has been a strong eastward flow preventing us from flying with as much of a westward component as we would like.

Because of this we are focusing on creating maps of the currents sub surface. By this afternoon, I plan on having a runway defined from our current location to Ascension (outlined with the 4 push pins in the image above) that will give us some more insight on the conditions we will be dealing with.

Finally, this week we welcomed some new members to our team.  Three Midshipmen from the Naval Academy and two Rutgers undergraduates will be interning with us for the summer.

Brendan Kahle, Alex Brecht, and Danielle Quinonez will spend some time this summer looking at the ocean models to help with navigation for Challenger on her way to Ascension while also delving in the Pacific and finding a path we will be able to fly with the new Thermal Gliders we will receive later this year

Collin Dobson and Jeff Mart will also be working with us this summer continuing their work from the previous semester looking into a comparison between the data collected by our Long Duration Gliders and the ocean models.

 

Force Wind Sea & Honor