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Wednesday, 4 December 2013

Boeing 247 Propeller Airliner


Developed in 1933, the Model 247 was an all-metal, twin-engine airplane, and the first modern passenger airliner. It had an autopilot, pneumatically operated de-icing equipment, a variable-pitch propeller, and retractable landing gear. It took the Model 247 20 hours, with seven stops, to fly between New York and Los Angeles. However, because the 247 flew at 189 mph, its trip was seven and a half hours shorter than that made by previous airliners.  Seventy-six 247s were built. Boeing Air Transport flew 60 Model 247s. United Aircraft Corporation flew 10, and the rest went to Deutsche Lufthansa and a private owner in China. The 247s remained in airline service until World War II, when several were converted into C-73 transports and trainers. Some were still flying in the late 1960s.






History
The Boeing 247 was the result of an effort by Boeing Aircraft Company in the late 1920's to seize a competitive edge in the air mail and fledging commercial passenger markets in the United States by designing a plane that was faster, safer, and capable of carrying heavier payloads than then-prevailing aircraft designs such as the Ford Tri-Motor, or older bi-plane designs such as the Curtiss Condor or Boeing's own Model 40.  Boeing at that time was more than a manufacturer -- it had a vital commercial interest in specific air routes operated by its corporate affiliates, including United Airlines and Boeing Air Transport.  The Boeing 247 was the first modern airliner, pioneering many design innovations that later became commonplace: the engine nacelle, the engine cowl, the variable pitch propeller, the three-bladed propeller, a functioning restroom, electrically driven retractable landing gear, a heated, pressurized passenger cabin, trim tabs allowing a pilot to adjust flight controls while airborne, and rubberized de-icing boots for the leading edges of the wings, elevators and tail surface.  

The 247 created quite a sensation at the Chicago International Exposition that summer.  For the remainder of 1933, 247's carried passengers and mail rapidly and routinely.  Service was so popular that tickets had to be booked well in advance.  Although it never bore a name, the 247 was the subject of a contest jointly sponsored by Boeing and United Aircraft among their employees to choose a name for the plane -- with a $25.00 prize, a hefty sum in the early years of the Depression.  Ultimately, "Skymaster," the brainchild of Cloyde L. Hoover of Boeing Air Transport, won.  Higher-ups at Boeing opted not to use the name as it broke with tradition, but Mr. Hoover got his $25.00.

For a full year, the Boeing 247 reigned supreme.  It was then superseded by a larger, more powerful design in the form of the Douglas DC-1. Ironically, the DC-1 was similar to a big airliner concept that some within the Boeing Company had advocated be built instead of the 247.  In part because of all the new technical challenges of the design that had to be overcome, Boeing made a conscious decision to construct a smaller, 10-passenger airliner to ensure that it remained in the forefront of commercial passenger service in the short run, and build a larger airliner over the next few years.  
While the advocates for the big airliner at Boeing lost the internal corporate debate, they had bitter vindication with the appearance of the DC-1 in 1934.






Construction :


The 247's instruction sheet is a bit unconventional.  It does not proceed step by step, but rather provides a few key illustrations augmented by photographs, all of which are self-explanatory for the most part.  It definitely requires the modeler to think, for no clear sequence of construction is provided.  This is an older, limited run "garage kit," and will require a bit more effort from the modeler.  However, as it is the only kit of a truly historic airplane, it's well worth the effort.

The Fuselage  :


The cabin and cockpit assemble without difficulty, but the cockpit seats are simply cemented to a bulkhead without the aid of guiding grooves or pins, and symmetrical positioning of the seats in relation to the cockpit door in the center of the bulkhead requires a fair amount of care.  In addition, the backs of the seats are rounded, making cyanoacrylate glue a must if the seats are to hold in place once they make contact with the bulkhead.  It's important to decide early on whether to build the racing or passenger versions of the 247, since each has a distinctly different cabin interior.  For the racing version, the ten passenger seats are discarded, and replaced by eight fuel tanks.  The cockpit is identical for both, with individual seats, control columns, and a decal for the instrument panel.  







Wings
Care must be taken at the point the wings are cemented on to determine whether it is best to add the landing gear, engines and cowlings at that stage, or wait.  Given the extensive sanding required to hide join seams on the underside where the center section of the wings, which is a separate piece, meets the rest of the wing assembly, I chose to wait.  Although the tray containing the interior protrudes from beneath the fuselage a bit, it will not cause difficulty when attaching the center section of the wings to the fuselage.

Finishing touches
I made the radio antenna from stretched sprue which I sanded to a point, then superglued to the cockpit roof.  The radio aerial is ceramic wire from Precision Enterprises Unlimited.

Conclusion
This is a great kit of historical importance, highly recommended, especially to modelers who are also serious history buffs.  Looking at it, one can see the seeds of more famous, more recognizable aircraft which owe their development either directly or indirectly to the Boeing 247, namely the Douglas DC-3 and Boeing's own B-17 bomber, both of which had a hugely significant role in what was then the coming World War -- and in the case of the DC-3, in both military and commercial aviation for many years afterwards.  Other than the windscreen and the landing lights, assembly is relatively easy, but like many limited run kits, the 247 definitely demands a bit more work of the modeler, and with effort and persistence you will have a rewarding result.  Luckily, aftermarket 247 decals can still be obtained by the patient hunters out there.  Hopefully the Boeing 247 will not be out of production too much longer, and may even return with new tooling. 

Specifications First flight:     Feb. 8, 1933
Model number:     247
Classification:     Commercial transport
Span:     74 feet
Length:     51 feet 7 inches
Gross weight:     13,650 pounds
Top speed:     200 mph
Cruising speed:     189 mph
Range:     745 miles
Ceiling:     25,400 feet
Power:     Two 500-horsepower P&W Wasp engines
Accommodation:     3 crew, 10 passengers, 400 pounds of mail


Regards,

Nidhi Jain [ MBA eComm]
Asst Project Manager [ eComm]
On Line Assistence :
Y! Messenger : NidhiJ.AeroSoft@yahoo.com


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