A semi-3D version of the arcade game Scramble. I say semi-3D as only the bottom and left wall of the tunnel are displayed as it scrolls from top right to bottom left.
The idea is that you have to fly your plane low enough to make strikes on the fuel dumps, radar installations, rockets and planes, but then climb fast enough to avoid the cross walls of varying heights that are forever coming towards you. All this, plus dodging the ground-to-air missiles that are launched at you, makes for a difficult and tense game - especially as the 3D effect makes it very difficult to judge your exact position relative to the missiles and the gaps in the wall. The shadow of your plane helps - if you can keep your eye on it as well as everything else!
Good use is made of the Spectrum's graphics and sound capability. The only slightly disappointing thing about the game was that the scroll is by character squares, not pixels, making the action rather jerky. But still, a small price to pay for an original angle on an old favourite.