NSL-85


Known to BRIGHTLinks students as NPSL-3, this flight flew the morning of July 25, 2020. This was a student launch organized by Christopher R. to fly several payloads similar to NSL-83 & 84. Included was:

    • 1m student-constructed parachute

    • Tim W's Femto APRS tracker

    • Christopher R's LightAPRS tracker that had an additional temp/humidity sensor added (all programmed by students)

    • Paul L's T-Beam LoRa tracker

    • student box containing three cameras

Femto, LightAPRS, and T-Beam housings

LightAPRS board with battery holder and external temp/humidity sensor

Student camera payload

The entire flight train massed around 850g and was lifted by H2 in a 600g cell.

The winds would briefly take the flight east towards Raleigh, and then circle back to the west, over Apex, and continue west until burst. A typical flight (ascent rate=5m/s) would likely land in Jordan Lake, so the balloon was under-filled to 1400g of neck lift (ascent rate=4m/s). This would hopefully take the flight further west away from the lake.

As the summer morning began to really heat-up, students held a countdown and released the payload.

View from a bottom facing camera of the launch site

Tim's tracker ran into reception issues, but the LightAPRS and T-Beam fed data to the Habhub.org. A LoRa receiver at Paul's home was able to pick up the T-Beam on the initial eastward leg.

As the flight passed back over Apex, the students and parents boarded their chase cars and headed west towards the predicted landing area. This was a collection of farm fields along US-64 near Siler City.

As the flight crossed over Jordan Lake, Paul's chase car receiver took over LoRa reception until the flight reached 22km. At that point his car's roof antenna fell into a strong antenna shadow and lost contact. Thankfully, the student's LightAPRS tracker continued to broadcast out to the group.

Burst occurred at 31,362m just west of Pittsboro.

Paul switching to the Yagi to receive the LoRa data during descent

One of the chase-mothers spotted the parachute first and many were able to watch its descent...

Payload coming back into sight

...directly into a stand of tall trees. The property was along a shooting range, so once permission was given, a team ventured out into the woods to find the payload. Sadly it was atop some large trees, so Tim was called in for the rescue.

Out to the landing site with bow and arrow

As expected, Tim was able to get a line up and over the payload and pull it down later that afternoon.

Flight visualization

Ascent and temperature data received from the trackers