A-23 Martin Baltimore
First flown by E.D. Shannon on June 12, 1941, the Martin 187B was dubbed the Baltimore, and differed from the Maryland by having Wright 1,600-hp R-2600-A5B engines, self-sealing fuel tanks, 211 pounds of armor, and a deeper fuselage for a four-man crew and four 500-pound bombs.
Fifty Baltimore I and 100 Baltimore II types had eleven .30-caliber guns; four fixed in the wings, two flexible guns for the upper rear cockpit, another for the ventral spot, and an unusual mounting of four belly guns pointing aft and fixed at an angle 9° down and 1.5° out. Hand-held upper guns were replaced on the 250 Baltimore IIIs by a Boulton Paul power turret with four .303-caliber guns.
By 1941’s end, 146 Baltimores had been accepted, and of the original 400 Baltimores accepted by June 1942, 356 went to RAF units in the Middle East, 35 were sunk on torpedoed ships, six went to the United Kingdom and one was retained by Martin. The first RAF mission was on May 23, 1942, in Libya, but Messerschmitts downed all four Baltimores, proving that light bombers still needed fighter escort.
After the Lend-Lease Act made available more funds for Britain, 575 more were ordered June 17, 1941. Since lend-lease aircraft were purchased by the United States government, they had AAF designations, including the Douglas A-20C Boston, the Lockheed A-28 and A-29 Hudsons, Martin A-30 Baltimore, and Vultee A-31 Vengence. (As the Hudsons were actually maritime patrol types, not attack planes, they are discussed in Chapter 20.)
The A-30 began appearing in August 1942, with two .50-caliber guns in a Martin power turret replacing the hand-held dorsal guns, and bomb bay ferry tanks so they could be ferried across the South Atlantic to Accra. The 281 Baltimore IIIA models were followed, beginning January 1943, by 294 Baltimore IV (A-30A-l/5). Six hundred Baltimore Vs (A-30A-10/30) with 1,700-hp Wright R-2600-29 Cyclones were ordered September 23, 1942, and delivery began by July 1943. Wing guns were now also of .50-caliber.
When production ended in May 1944, 1,575 Baltimores had been built, 78 had been lost before or during flight deliveries to Africa, and the last one was retained by the U.S. Navy for tests. All combat missions were flown in the Mediterranean area.
Besides ten RAF and three South African squadrons, Baltimores also served a Greek squadron in 1944, and became the last bomber used by the Italian Air Force when 34 were supplied to a unit of the Co-Belligerent Air Force from November 1944 to May 1945. Although neutral, Turkey also received 72 Baltimore Vs, beginning in August 1944, while 12 were given in 1945 to a French squadron in Syria.