This one is for finishing a level of Attack Of The Mutant Camels (Atari 8-bit version) with 9 shields.
It doesn't matter how many jets you have left, the number of shields are the only thing that matter.
I set the difficulty to "REAL COOL" (the easiest), set the blaster bullet potential to 8 (the strongest), and then on the 1st level, just killed all but one camels (shooting mostly at their feet seems very effective). I then let the final camel kill me, so I would have 9 shields left before completing the level. Don't worry about the next stage warp, the achievement pops before then.