Smoke for base defense?
How much real ordnance can it carry?
"The sparkling low level performance of the Boomerang combined with a tough structure was ideal for this alternate role. 4 and 5 Squadrons operated the Boomerang in Papua New Guinea and the Solomon Islands. In the tactical role, as well as strafing (armament being four .303 machine guns and two 20mm cannon) the aircraft were also used for artillery spotting and close support, and 'FAC' type work marking targets. It is in this later role that the type became well known to some New Zealand pilots. The 'Smokey Joes' used four 9kg (20lb) smoke bombs carried under the centre section to mark targets for RNZAF Corsair fighter-bombers. The aircraft could also carry up to a 227kg (500lb) bomb on the center line"
CA13 Boomerang:
Role: Fighter aircraft
Manufacturer: Commonwealth Aircraft Corporation
First flight: 29 May 1942
Introduced: 1943
Status: Retired
Primary user: Royal Australian Air Force
Produced: 1942–1945
Number built: 250
General characteristics Crew: 1
Length: 25 ft 6 in (7.77 m)
Wingspan: 36 ft 0 in (10.97 m)
Height: 9 ft 7 in (2.92 m)
Wing area: 225 ft² (20.9 m²)
Empty weight: 5,373 lb (2,437 kg)
Loaded weight: 7,699 lb (3,492 kg)
Powerplant: 1× Pratt & Whitney R-1830 Twin Wasp radial engine, 1,200 hp (895 kW)
Performance Maximum speed: 305 mph (265 knots, 491 km/h) at 15,500 ft (4,730 m)
Range: 930 mi (810 nm, 1,500 km)
Service ceiling: 29,000 ft (8,800 m)
Rate of climb: 2,940 ft/min (14.9 m/s)
Wing loading: 34.2 lb/ft² (167.1 kg/m²)
Power/mass: 0.16 hp/lb (256 W/kg)
Armament
Guns:
2× 20 mm (0.787 in) Hispano or CAC cannons
4× 0.303 in (7.7 mm) Browning machine guns
Bombs: up to 500lb on the center line could be fitted when the large drop tank was not carried or four 9kg (20lb) smoke bombs.
Here is a good site on the history.
http://www.aviastar.org/gallery/boomerang.html 
