Here are the rules I’ve devised for the cannon armed SPAD XII in Algernon Pulls It Off!

SPAD XII

SPD 7

MAN 3

CLG 10 

ROC 2

ROB 3

SIZ 2

F/F Front  2 or 8*

*Vickers 7,7mm machine gun (35 seconds of ammo ) or 37mm S.A.M.C. (single shot / 12 rounds)

Only available to Junior Ace or Top Ace pilots. 

Only one aircraft may be deployed per game.

Vickers machine gun and S.A.M.C. cannon cannot be fired at the same time.

37mm Cannon

Burst Duration – divide maximum length of burst in half, rounding up (representing time to aim)

Modify Fire Factor for Length of Burst and the usual +/- die modifiers. 

Calculate Attacker / Defender hits vs saves as usual.

If a hit is scored, refer to the Hit Effect table (10.1)

Results

Firer Sideslips = as normal

Overuse of Anmo = cockpit fills with smoke and pilot is disorientated. 

Make a Pilot Control Test counting the test as a Hard manoeuvre and apply the results.

M* or M = C

C = 2C

2C = X

X = X 

Shift columns to the right on the Critical Damage Table accordingly.

Note: Pilot Hit = Pilot Killed.

The 37mm cannon must be reloaded after each firing (9.7) 

Vickers 7.7mm machine gun

The Vickers machine gun may be fired instead of the cannon unless cannon is being reloaded.

Use the normal firing procedure.