Here are plans for the Douglas A-20 Boston / Havoc Bomber that I
electronically scanned from my purchased copy of the November 1970
American Aircraft Modeler magazine. Because they span two or more
pages, you will need to adjust the size and alignment a bit to get
halves to line up properly. You might be able to scale up the images
below is plans can no longer be purchased. Plans for this fine model
were drawn by
Mr. Björn Karlström. All copyrights (if any) are hereby acknowledged.
The AMA Plans Service offers a full-size version of plans at
a very reasonable cost. They will scale the plans any size for you.
Try out my
Scale Calculator for Model Airplane Plans.
Douglas A-20 saw widespread service in many roles throughout
World War II
Photos by Howard Levy
An RAF Boston III in Egypt in 1943. Photo
fortunately reveals the twin swivel-mounted guns in rear cockpit,
gun pod on side of nose.
MORE THAN SEVEN THOUSAND were built, yet it doesn't stand out
as one of the major types in the history of military aviation. Produced
as both a bomber and a fighter, it entered service before Pearl
Harbor and remained operational to the end of the Second World War.
Yet few, aside from those who flew the Douglas A-20 or one of its
many variations, remember the type as anything more than a familiar
light twin that did many jobs well, but never did anything really
Perhaps because of its origins the Havoc or Boston, or whatever
you want to call it, is something of an under-appreciated airplane.
It began as the Douglas Model 7 A, a company project intended to
be the U.S. Army Air Corps' first twin-engined attack bomber. The
original 7 A never was completed, but the 7B flew for the first
time late in 1938, at more than 300 mph---quite a speed for bombers
in those days. It was not only fast, but it also was unusually well-armed,
with eight .30-cal. machine guns in the B version and an additional
four in the solid nose of the A version.
While the airplane looked highly promising to the USAAC, the
first orders came from the French who contracted for 380, highly
modified in light of what had been learned in the Spanish Civil
War. Known as the DB-7, fewer than half of those ordered were delivered
to France before that country fell to the Germans, and hardly any
of those planes got into action. By a variety of routes, a large
number of them came to the Royal Air Force, where they were pressed
into service as trainers, bombers and fighters, including some of
the first radar-equipped night fighters.
of the desperate need for night fighters to hold off the German
He-Ills, Ju-88s and Do-217s, the British tried some novel ideas,
including trailing a bomb on a 2000-foot cable behind the Pandora
version of the Havoc I, in hopes of dragging it into low-flying-
bombers. A more practical idea was the Turbinlite, a monster searchlight
grafted onto the nose of a Havoc or Boston, in place of the far
more graceful solid or clear nose. The intention was to' light up
enemy aircraft so that they could then be shot down by single-engined
fighters. Before the system was fully developed-if, indeed, it ever
could have been-airborne intercept radar came into being and the
bulky light was replaced by strange collections of antennas.
All the while the British were enthusiastically using the trim
Douglas fighter/bomber, the U.S. was moving ahead with its plans.
The first A-20A's were ordered in July 1939, and deliveries commenced
in 1940. By 1941, as the war in Europe gained intensity and U.S.
entry neared, orders for the machine poured in from not only the
USAAF and the RAF, but also from European governments-in-exile who
were fighting from British bases.
As the airplane saw more action, it was continually modified.
Armament was increased, as was the bomb load. To handle the rapidly
increasing weight, the original Pratt & Whitney R-1830 Twin
Wasp engines of some 1100 hp. were replaced by Wright R-2600 Cyclones
of 1600 hp. Early problems with directional stability were corrected
by enlarging the vertical tail, thus changing its original highly
tapered form to the more familiar squared-off shape.
1942, substantial numbers of A-20's were being sent to the USSR,
some of them for the Soviet Navy's use as torpedo bombers. In all,
nearly 3000 went to the airplane-hungry Russians. Most of these
planes were A-20G's with heavy batteries of guns in the nose, which
made them highly effective against tanks and other hefty ground
The RAF's successful use of modified bombers for night-fighting
purposes did not escape the notice of the USAAF, and about 270 A-20's
were converted into what was then the Army's heaviest fighter plane,
the P-70. The first of these carried four 20-mm cannon in a special
package under the fuselage. The P-70 was used primarily to train
pilots who eventually were assigned to the North- (the rest will
be scanned on request)
|A-20 - first
production version for USAAF; Wright R-2600-7
engines; 59 converted to P-70, 1 to XF-3, 2 to YF-3.
A-20A - 143 built with R-2600-3 engines.
XA-20B - 1
A-20A tested with three power turrets.
A-20B - 999 built
with Wright R-2600-11 engines.
A-20C - 948 similar to
RAF Boston III, Wright R-2600-23 engines.
A-200 - never
built; would have had R-2600-7 engines.
A-20E - 17 A-20A
modified with Wright R-2600-11 engines.
XA-20F - 1 A-20A,
one 37 mm cannon, two power turrets.
A-20G - 2850 built
with Wright R-2600-23 engines.
A-20H - 412 as A-20G
with 1700-hp Wright R-2600-29 engines.
A-20J - 450 built
as A-20G with bomber nose; 169 to RAF as
A-20K - 413 built as A-20H with bomber nose.
BD-1 - several A-20A built for U.S. Navy.
8 A-20B built for U.S. Navy.
OB-7 - original design of
series, ordered by French, diverted to
RAF as Boston I and II. Pratt & Whitney R-1830 Twin
OB-7A - 100 for France become RAF Havoc
II. Wright R-2600
OB-7B - 300 for RAF as Boston III.
- 48 similar 10 Boston III for Dutch AF in exile.
- 1 DB-7 tested by France with twin rudders.
photo version of A-20.
|YF-3 - 2 A-20
converted to photo recon.
F-3A - 46 A-20J and A-20K
converted to photo recon.
0-53 - 1489 photo recon versions
of A-20B cancelled.
XP-70 - A-20 modified to fighter
with four 20 mm cannon in nose.
P-70 - 59 A-20 modified
P-70A-1 - 39 A-20C modified as fighters.
P-70A-2 - 65 A-20G modified as fighters.
- 1 A-20G modified as fighter.
P-70B-2 - 105 A-20G and
A-20J modified as fighters.
Boston I - ex-French DB-7's
to RAF for training.
Boston II - ex-French DB-7's to
RAF as bomber.
Boston III - 300 ex-DB-7B's to RAF.
Boston III Tutbinlite - three Boston III with 2.7 billion
light in nose.
Boston IIIA - Boston III built by Boeing
Boston IV-169 A-20J for RAF.
A-20K for RAF.
Havoc I - ex-French DB-7's 10 RAF as
Havoc 1 Turbinlite - 31 Havoc I, 2.7 billion
candlepower light. Havoc II - ex-French DB-7A's to RAF.
Havoc II Turbinlite - 39 Havoc II modified with light
Havoc III - became Havoc I "Pandora" version;
Havoc IV-become Havoc I (Intruder).
Douglas 7A - prototype, fighter nose, P&W R-1830 engines.
Douglas 7B - prototype, bomber nose, P&W R-1830 engines.
<click for larger
Douglas A-20 Boston / Havoc Bomber
Article & Plans
Douglas A-20 Boston / Havoc Bomber Article & Plans
<click for larger
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version of many of the plans show here at a very reasonable cost. They will scale the plans any size for you. It is always
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will be glad to send you my higher resolution version.
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