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Glenn L. Martin

Martin Aircraft

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Martin 2-O-2, 3-O-3 and 4-O-4 Airliners

Looking ahead to the postwar world, Martin executives looked forward a fundamental change in the company's business. Except for the four clippers, Martin had built only military aircraft for two decades. Now the company expected a mixture of 25 per cent commercial business and 75 per cent military. Martin planners had already begun to dream up commercial ideas. Huge flying-boat airliners topped the list, but several lines of small private planes were also considered, and the company invested in a plastics plant. The decision was ultimately made to concentrate on building a faster, more modern airliner designed to replace the eleven-year-old Douglas DC-3, then the mainstay of the nation's airlines. In September 1944, plans for a 30-passenger Martin Model 202 were sent to the Aircraft Requirements Committee of the Air Transport Association. It had a cylindrical fuselage and was to be powered either by Wright R-2600 or Pratt and Whitney R-2800 engines, mounted on wings either above or below the fuselage. With its high "shoulder" wings, the 202-12 version looked rather like a B-26 Marauder, a point noted in the press release. This would, it said, enable quick conversion of the Martin plant and workforce. It would also contribute to the new airliner's safety - a mark of how much the Marauder's reputation had changed by mid 1944!

Martin was determined to make the earliest possible entry into the postwar airliner market, unveiling a full-size mock-up within two weeks of V-J Day. In its final form, the Martin 2-O-2 - as the plane was to be marketed - had grown to 40-passenger size. As had been the case with the PBM and B-26, Martin proposed a two-engine plane that could carry the same payload as a four-engine one, in this case the Douglas DC-4. Design was tricky. To cruise at 250 mph, slim high-aspect wings much smaller than the DC-3's were required. Without using new technology, they would be unable to duplicate the DC-3's short take-off and landing runs. Maxwell Bassett, the 2-O-2's chief designer, employed new flap and slot controllers devised by the inventor Charles Hampson Grant and a new "sharp-nosed" aileron seal designed by Willem D. van Zelm of the Martin Engineering Department. Other innovations included reversable propellers for easy maneuvering on the ground, underwing refuelling points, and a built-in passenger stair.

Sales went well. Led by orders of fifty planes each from Pennsylvania Central (Capital) and Eastern, six airlines placed orders by the end of 1946. Two others, United and Northwest, wanted pressurized cabins for their high-altitude western routes. Martin obligingly launched another new design marketed as the Martin 3-O-3. United even looked ahead to a turboprop 3-O-4. Despite competition from Martin's old rival Consolidated, which was developing a very similar plane in the Convair 240, Martin gathered in orders and promises for nearly 300 2-O-2's and 3-O-3's. While the new planes took shape, a cadre of trained employees were kept on at Middle River converting 110 wartime C-54 transports into DC-4 civilian airliners.

It took more than a year to built the first 2-O-2, which took to the air in November 1946. After the first round of flight testing, two expensive "fixes" were ordered. The first two planes built, intended as production models, served as prototypes. Their nearly flat two-degree wing dihedral was altered to eight degrees on the first prototype (NX-93001) and ten degrees on the second (NX-93002). Wedge-shaped forgings were designed to tilt up the wing panels outboard of the engine nacelles: the ten-degree angle proved more successful. Two new dorsal fins were also designed to enlarge the vertical sections of the plane's tail. The larger of the two, first installed on NXC-93002, was adopted.

The spring of 1947 was a bad time for design delays. A recession reduced the airlines' revenues and credit lines. Several, including Eastern and PCA, canceled or reduced their orders. Nervous about the safety of the first post-war airliner, the Civil Aeronautics Administration ordered a lengthy and exhaustive set of precertification tests that lasted all summer. The Airline Pilots' Association objected to an automatic prop-feathering system added by Martin to increase small-field payloads. As development costs mounted, Martin had to apply for a $25 million RFC loan to tide the company over until sales revenues came in. The 2-O-2 was finally certified in September - still two months ahead of the Convair. Deliveries began immediately, with Northwest Airlines being the first to put the new airliner into service. Laid-off workers were recalled and assembly lines at Middle River put back on a wartime pace of three shifts a day.

Then the bottom fell out. First, the pressurized 3-O-3 had to be abandoned. Its wings had been designed in one piece, like those of the B-26, so there could be no simple fix for the dihedral. Rather than wait, United and other customers went over to Convair. Northwest, the only domestic airline with 2-O-2's in service, obligingly ordered another 15 to replace its cancelled 3-O-3's. Then in August 1948 one of the Northwest planes crashed during a Minnesota thunderstorm, killing all 37 people aboard. Another 2-O-2 that flew into the same storm emerged with a crack in the wedge-shaped forgings that had given the wings their dihedral. After a lawsuit brought by Northwest, Martin agreed to rebuild and strengthen the wings on all surviving 2-O-2's. Except for six planes sold to LAV of Venezuela and LAN of Chile, commercial orders dried up entirely.

In the crisis Martin turned instinctively to the military. A 2-O-2 was flown to Wright Field for evaluation as a transport, while company literature explained how a fleet of 750 of them could handle not only the Berlin Airlift but also all training for bomber crews. Another possibility for sales was offered by Stratovision, a joint project of Martin and Westinghouse for broadcasting television signals over long distances. In June 1948, a Stratovision-equipped B-29 flying 30,000 feet above Zanesville enabled the television owners of central Ohio to see Thomas E. Dewey nominated for the presidency. Similar events could be seen nationwide, claimed company publicity, with a fleet of 60 Martin 2-O-2's - though operating television stations at 30,000 feet in their unpressurized cabins would have been a chilly proposition. No alternative customers turned up.

In the fall of 1948, Glenn Martin and his mother flew in one of the prototypes on a tour of their old homes, stopping for honors in Cleveland, Los Angeles, and Santa Ana. The tour turned out to be a swan song. With losses in 1947 and 1948 amounting to $35.4 million, Martin had to go back to the RFC for more money in 1949. The agency demanded that Glenn Martin give up the operation of the company, though he remained as Chairman of the Board. The new president, Chester Pearson, was a young executive brought over from another ailing manufacturer, Curtiss-Wright.

With the new RFC loan and the 2-O-2's losses written off, the Martin Company returned to the black in 1949. The inertia of the airliner program, however, had not yet run out. Tempted by the parts and tooling still in place, Pearson took another chance on the commercial market. In March 1950 the Martin 4-O-4 was announced, a somewhat larger two-engine short-haul airliner, now with a pressurized cabin. The initial planes would once again have Pratt and Whitney R-2800 piston engines, but the wings would be stressed for turboprops. Eastern Airlines and TWA purchased a total of 103 of the new airliners. In addition, Howard Hughes negotiated a complicated arrangement by which TWA would lease a dozen 2-O-2's until its 4-O-4's were ready. To the cheers of Martin workers, the assembly line in D Building was re-opened immediately. Twelve slightly modified 2-O-2A's were quickly assembled from surplus parts and put in service by September.

Building the 4-O-4 took longer. Improvements meant that 80 per cent of the new plane was new and could not be built from leftover 2-O-2 parts. Costs rose again under the impact of inflation from the Korean War which broke out three months after fixed-price contracts for the 4-O-4 had been signed. Production was slowed by wartime materiel priorities. Once again, Martin needed an infusion of cash, but the RFC refused another loan. Private lenders, led by Mellon Bank, imposed even more drastic changes in company management in 1952. This time Glenn Martin was removed entirely - and literally. His office was moved off the premises, and his stockholdings cut in half by a new offering. George M. Bunker, who had made his name at Trailmobile, Inc., was brought in as president, along with other non-aviation executives. The company's founder died in retirement two years later.

The 103 4-O-4's sold to Eastern and TWA (and two more purchased by the Coast Guard) proved to be sturdy airplanes in the Martin tradition. After a decade or so with the trunk lines, they joined the former Northwestern 2-O-2's in service on regional carriers. Some were converted into executive planes (including one for Frank Sinatra) and others used to carry cargo (not always legal). Several were still flying in the 1990's, including 4-O-4's owned by the Mid Atlantic Air Museum, Save a Connie, Inc., and a private collector in Washington - displaying the liveries, respectively, of Eastern, TWA, and Pacific Airlines. At least two 4-O-4's have been impounded by the U.S. Customs Service and await possible restoration. A Martin 2-O-2 may be seen on static display at the New Jersey Aviation Hall of Fame at Teterboro Airport. A 4-O-4 is available for viewing at the Glenn L. Martin Maryland Aviation Museum in Middle River, Md.

First 2-O-2 NX93001

2-O-2 NC93003

Prototype 3-O-3

TWA 4-O-4 N40401

© 2006 The Glenn L. Martin Maryland Aviation Museum
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