Power Line Seeker III Build


"Power Line Seeker III" is the 3rd iteration of my 75mm minimum-diameter line of projects. Unfortunately, versions I and II are no longer flyable. This series of projects is named after version I (formally Great BALLS of Fire) landed in some high-voltage power lines nearby Brothers, resulting in numerous complications with the power company. (Some of which still aren't even fully resolved...a year later.)

Check out the build page for Power Line Seeker I to find out what happened to it. Power Line Seeker II only flew once and hence doesn't have a build page, but some specifics are available on The Rocketry Forum. Hence, on to version III!

This project has many similarities to its 98mm counterpart, Bells On, so there will several cross-references with that build. Construction of Power Line Seeker III began in March 2016 and is currently in progress.


  • Length: 6 feet, 5 inches
  • Diameter: 3 inches
  • Motor: 75mm (minimum diameter)
  • Airframe material: Fiberglass
  • Fin material: Fiberglass
  • Nosecone material: Fiberglass
  • Altimeters: Featherweight Raven3 and a PerfectFlite StratoLoggerCF.
  • Recovery: Rocketman 24" drogue and a Rocketman 4' main.

Construction Photos

Note: Construction of this rocket is currently in progress. Additional photos will be posted here as they become available.

Fiberglass components, manufactured by ProLine Composites and purchased from Madcow Rocketry.

Fin Can

Fins were cut exactly the same way as they were for Bells On - 1/8" G10 fiberglass sheet cut on the table saw, then sanded and matched on the belt/disk sander. They were even cut from the same sheet of fiberglass...

Beveled using a masonry cutting wheel on the table saw, and then the belt/disk sander.

Fin #1 glued on with Loctite E-120HP epoxy, next to Bells On.

Fins #2 and #3 tacked on.

Lastly, Fin #4 tacked on.

More to come!