Game Main > Rocket Flight
ρ=Σ+Ψ

Rocket Flight: Lords of the High Frontier

designed by Philip M. Eklund

1995, Sierra Madre Games Co.

Out of print

(Please note: the above map is not the one supplied with the game. It is one I drew in tribute to this great game.)

The game gem in Rocket Flight is the strategic map. Unlike other games strategic space maps, it is not a map of, well, space. It is a map of energy states. Let me explain.

If you have a typical gasoline-guzzling USonian automobile, you might get 20 miles per gallon of gasoline/petrol. You expend one gallon of gasoline, you move 20 miles. And then you sit there, until you expend more gasoline. Friction is such an annoying thing.

So the standard wargame hexgrid/counter-with-movement-points system models armies, air battles, and naval engagements quite well.

But spacecraft don't work that way. If your spacecraft is quote "stationary" unquote, and you expend reaction mass to change your spacecraft's velocity to five kilometers per second, it's gonna move at five kp/s for the rest of eternity. (At least until acted upon again by some force, wiping out on a passing comet for instance).

The Rocket Flight strategic map does not have hexes that represent X thousands of kilometers of space. Instead, each hex represents a delta V (i.e, change in velocity) of three km/s. So by measuring the distance between planets in hexes, one determines the delta V required to move the spacecraft to that planet.

This is convenient, since that is the units that spacecraft propulsion is rated in.

Therefore a map gridded in delta V models the situation much better than one gridded in distances.

Genius, pure genius.

Details:

To move one hex on the delta V map, a number of fuel points must be burnt. The amount depends upon the spacecraft's "dry mass" (i.e., the crafts mass without propellent aka "fuel points") and the specific impulse of the spacecraft's propulsion system.


Amount of propellant mass expended in order to move one hex on delta V map
Specific Impulse (km/s)
Dry Mass 0-5
DM 6-10
DM 11-20
DM 21-30
DM 31-99
800
-
-
-
-
0.1
100
-
-
-
-
0.5
32
-
-
0.5
0.5
1
16
-
0.5
1
1
2
8
0.5
1
2
2
4
4
1
1
3
4
7
3
1
2
4
6
10
2
2
3
6
9
15
1
4
8
16
24
40


The spacecraft can move two hexes (in one turn) if it burns four times the specified fuel points, three hexes with eight times the points, four hexes with 16 times the points and 5 with 32 times the points.

However, the various propulsion systems have a maximum "mass rate", which is the maximum amount of fuel points that system can burn in one turn. This cannot be exceeded.

Note that the various propulsion systems in this game are based on accurate information. The table of engine specs in the back is worth the price of the game all by itself.


Bonus cool game bit: Gravitational Slingshot

A spacecraft moving into a delta V hex containing Earth or Venus is allowed to immediately move one free hex in any direction (except as noted below). A spacecraft moving into the Jupiter hex may immediately move up to four hexes.

The "Wrong Way Corrigan" rule: when making a slingshot, the spacecraft must turn. If the new hex is collinear with the start hex, the spacecraft is assumed to have collided with the planet and is destroyed. Opponents should watch all slingshots to see opportunities to invoke this rule.


The Rocket Flight map system is being adapted to the Attack Vector game system. It will be called "High Trader". There is a sample map here (click on "High Trader Delta V Map of Olympia").

When you look at the map, the important thing to realize is that each "square" or playing space is an entire orbit. When a starship counter is in a square, this represents a starship moving in an orbit even though the counter is stationary. This is done by using rotating frames of reference.

Keep an eye on Ad Astra games to see how this game concept turns out.