Touchdown

Gravity keeps changing the craft’s speed while you decide when to fire its engine. Reach the pad, arrive gently and keep enough fuel to make the corrections that matter. Each attempt begins from the same situation, so another try can use what the last one taught you.

Use a 48K ZX Spectrum or an emulator configured as that machine. The completed game uses O/P to steer and Space to thrust; those controls can be held together. S launches, R retries after contact, and Q alone quits after release. Fuel exhaustion disables the engine but leaves the flight going.

Touchdown follows Volley. We recall its continuous updates, candidate positions and consecutive erase/draw, then explore velocity, fuel and a landscape whose shape affects contact. Each lesson explains its BASIC locally; neither assembly nor Foundations is a prerequisite.

Learn the approach in smaller games

First watch a constant fall, then add gravity and unlimited thrust. Make that vertical game complete before limiting fuel. A generous pad on flat ground gives steering room to develop before the ridge and narrower target appear.

1. Let the craft fall
2. Let gravity change the speed
3. Brake before you arrive
4. Make another attempt
5. Make each burn count
6. Reach a landing pad
7. Steer and thrust together
8. Give every column a ground height
9. Read the shape of the site
10. Draw the craft and its flame
11. Finish, test and keep Touchdown

Every lesson has a complete runnable checkpoint. Additional checkpoints let us inspect simultaneous keys without flying, change terrain representation without changing its shape, and build the custom craft before its flame. Keep the simpler versions as useful practice and comparisons.

The full approach is demanding. The simpler games give us room to understand and practise its demands; there is no requirement to land on the first attempt. The final lesson compares difficulty changes one at a time and ends with a saved game that can be reopened and shared.