NSL-66

This flight was launched at 1300EDT on Sept 13, 2018. Hurricane Florence was just off the NC coast and making its approach. This simple flight was launched to see what the conditions were during hurricane. Can the flight predictions be counted on this close to a hurricane? How is the turbulence? Can you see anything up there other than a sheet of white clouds?

The payload was very simple and somewhat expendable. Flight NSL-61's (&63) hardware was re-flown, minus the Pi-in-the-sky module. So this was just a 9m orange ribbon with parachute and a small plastic box with an AP510 (new antenna attached) and an 808 #16 camera. These both shared the same 4200mAh Lipo battery. Originally, an OHCRAP module (white spool) was attached to the payload, but all agreed that the nearby rain would activate it too soon and would tangle things; so it was removed prior to launch. The entire payload was around 250g. And was all lifted up with a 600g cell with 1100g of neck lift via H². The parachute was a bit over-sized considering the items removed from the payload, so we expected that it would come down slowly.

As the triangle was just starting to experience the first gust of winds, we needed to find a place that was somewhat sheltered to fill the balloon. A north Raleigh launch favored a better landing area, so our trusty parking deck in north Raleigh was used again. This also allowed Chris to join the launch crew of Paul and Matthew L. After launch, Chris would switch to PAO duties.

We were able to fill the balloon on the topmost parking deck ramp, which afforded some protection from the wind. The balloon was then carried up to the top of the deck and released. In 360-degree video below, look to the left of the water tower at time 1:36.

Sadly, during sealing of the payload, the camera's ribbon cable was knocked slightly ajar. This caused much of the video to have a psychedelic shift of hues to it. At worst, the video looked like this strange launch image. At altitude, it just gave a 'posterized' view of the edge of the atmosphere.

Above is a NOAA GOES-East satellite image taken during this flight. The red dot is location of balloon at the time of the image was taken. Note the two vertical gaps in the clouds over the I-85 corridor to the left of the dot. These are clearly visible in the flight video. Below is a still from the same time looking southwest at 30km up.

Paul, Robert, and Matthew L. were on chase crew, southwest of the Triangle. Pleased that the flight followed the predicted track closely, they waiting in the expected recovery area when it landed. A grove of trees prevented them from spotting the payload float down a mere 0.5 km away.

As is usually the case, the payload was attracted to a small forest and found the top of the tallest tree there. The chase team went in and located it, but there was nothing to do but head back home and hope that the hurricane would knock it down. Which it did! There were very few limbs knocked down in that particular forest, but thankfully the one that held our payload gave-way and fell all of the way down. This slammed the payload face-down in a puddle. Parts of the AP510 got damp, but the camera was high and dry.

Surprisingly, the gravity waves from the hurricane were not any stronger than on "normal" flights. There were some up/downdrafts though. They greenhouse-style payload stayed toasty warm through the entire flight.

Can the flight predictions be counted on?

The Habhub prediction software is right on the mark ~12 hours from a hurricane coming ashore. The payload landed 2km from the predicted site.

How is the turbulence?

The small payload was mounted at the end of a 9m line. + It's low mass was compact and it had no outriggers to affect angular momentum. = It spun like crazy. But that is pretty typical for this sort of rig. The payload wasn't treated as violently as in NSL-63. So turbulence was not much of a worry.

Can you see anything up there other than a sheet of white clouds?

Well, not really. This close to land, the hurricane's eye wall was clouded over. So it was pretty much just a sheet of white clouds against a black sky, even at 100,000 feet.