Chopper Command

Released in 1982
Atari 2600

In Chopper Command you control a giant orange helicopter with a cannon of some sort. It's your job to protect convoys of trucks on the ground whose sole mission is to continue driving west at all times. There are evil blue jets, and evil white helicopters who wish to destroy these westbound trucks. Their weapon of choice is a missile that splits into 2 separate bombs that travel straight up and straight down. They will also fly straight into you if given the opportunity. Once you clear a board of all enemy aircraft, more appear, and you destroy them too. This, like most Atari games, is unceasing. Enemy aircraft get progressively faster with each wave until you can no longer move fast enough to avoid their suicidal tactics.

As a kid, I really enjoyed this game, mainly because of it's sound effects and controls. The helicopter has inertia when changing directions, and has a helicopter rotor sound effect that I'm sure sounded super cool pre-Nintendo. It also allowed players to just hold down the fire button for rapid fire instead of mashing it over and over again. Groundbreaking stuff, I know.

Today the game is just another ugly repetitive shooter. It's controls are still solid, and the sound effects aren't nearly as annoying as most 2600 games. It's definitely the most enjoyable game yet in these retro gaming reviews.
Games like Chopper Command and Defender definitely seem to be the progenitors of modern side scrolling shooters like R-Type, Ikaruga, or Omega Five (see right). The genre has definitely evolved significantly, but games like these are certainly the seeds to the "shmup" genre.