This is a Big Bertha modified with a three18mm motor cluster, 6" payload section/12" body section. This is essentially the same as the old Astron Ranger. I got the idea for this from an article by Bill Owens in the July 1996 MARS Pathfinder. The plans (in PDF format for Adobe Acrobat) for the Astron Ranger can be found here. I finally flew this after making some clip whips for my 12-volt launch system.
Dia: 1.64"; Length: 24"; Wt.: 2.4 oz.; Motor (3): 18mm
Recommended motor: A8-3, B4-4, B6-4, C6-5
Status: Damaged.
| Flt | Date | Motor | Comments |
|---|---|---|---|
| 1) | 6/07/97 | A8-3 | Nice flight, all 3 motors lit. My first cluster launch. Used 12" chute. |
| 2) | 6/08/97 | B6-4 | All 3 motors lit, another nice flight. |
| 3) | 7/14/97 | C6-5 | Yet another nice flight. |
| 4) | 7/16/97 | B6-4 | |
| 5) | 7/17/97 | B6-4 | |
| 6) | 7/31/97 | A8-3 | |
| 7) | 8/22/97 | B4-4 | Cluster flight for NARTREK Silver level. |
| 8) | 3/15/98 | C6-5 | Very nice flight. |
| 9) | 3/21/98 | C6-5 | Only one motor lit, though all ignitors lit. A short, arcing flight, hit the ground and broke one fin in half, two others cracked the fin-body joint. Looks repairable. |
| 10) | 7/25/98 | C6-5 | Only two motors lit, but OK flight. |
| 11) | 8/22/98 | A8-3 | |
| 12) | 1/30/99 | B6-4 | |
| 13) | 1/30/99 | C6-7 | Perfect flight and delay. |
| 14) | 4/11/99 | C6-7 | Only two motors lit, broke a fin on landing. |
Pictures
Big Bertha 3.
Business end of the Bertha3 after its first launch. 6/07/97.
