Model Variants (Including Prototypes)
Model 7 - Private Douglas venture design to replace current US Army single-engine attack aircraft.
Model 7A - Proposed light bomber with improved 450hp radial engines.
Model 7B - Followup proposed light bomber with Pratt & Whitney R-1830 radial engines devlivering 1,100hp.
DB-7 - (Douglas Bomber 7) Original French order placed featuring R-1830-S3C4-G radial engines and longer fuselage.
DB-7A - Wright R-2600-A5B radial engines; Improved variant.
DB-7B - Redesigned with British equipment; Enlarged vertical tail surface structure; Redesignated Boston Mk III.
A-20A - Initial production model to go in service with Britain and Commonwealth nations; "Havoc" name officially adopted; 143 examples produced.
A-20B - First major order in terms of overall numbers for Soviet Lend-Lease Act; 999 produced.
A-20C - "Improved" A-20A model; 4 x 7.62mm machine guns in nose; improved Wright engines of 1,600 horsepower; self-sealing fuel tanks; increased armor plating; 948 total produced by/for Douglas including 140 by Boeing.
A-20D - Proposed high-altitude version; intended powerplant of turbosupercharged Wright Cyclone radial engines; canceled before production.
A-20E - Test Models converted from A-20A models; all fitted with Wright R-2600-11 Cyclone engines; 17 total conversion ecamples.
XA-20F - Single A-20A model example set aside for nose armament and powered-turret tests; 1 x37mm nose cannon trialed along with 2 x 12.7mm machine guns in powered dorsal and ventral turrets.
A-20G - Sans-bomb aimer in nose; Solid nose with 8 x machine gun battery; Highest production rate of entire A-20 series; production blocks of A-20G-5 to A-20G-15, A-20G-20 to A-20G-45 with various minor changes throughout; 2,850 examples produced.
A-20H - Similar to A-20G-45 block model with increased MTOW and upgraded engines (Wright R-2600-29 series radials); 412 examples produced.
A-20J - "Lead Ship" aircraft model based on A-20G with glassed-in nose and bombardier position; 450 examples produced.
A-20K - "Lead Ship" aircraft model with glassed-in nose and bombardier position based on A-20H models; improved powerplant, improved armament capabilities and updated onboard equipment; Represents final production version; 413 examples produced.
Boston Mk.I - British redesignation of DB-7.
Boston Mk.II - British redesignation of DB-7A.
Boston Mk.III - British redesignation of DB-7B; DB-7B model with enlarged vertical tail surface and featuring British equipment internally.
Boston Mk.IIIa - A-20C models via Lend-Lease
XP-70 - Converted A-20 to Night-fighter with glass-nose section painted black housing 4 x 20mm cannons.
P-70 - Night-fighter Variant Conversion base model.
P-70A-1 - Converted A-20C model to Night-fighter role.
P-70A-1 - Converted A-20G model to Night-fighter role.
P-70B-1 - Converted A-20G-10-DO Night-fighter.
P-70B-2 - A-20G / A-20J converted trainers for Northrop P-61 crewmembers.
F-3 - Base A-20 conversion to Night-time photography and reconnaissance.
F-3A - Night-time Photography and Reconnaissance Conversion of A-20J and A-20K models.