Boeing Air Transport  Boeing 40-B-4  NC842M        (c/n    1168)


                                        Since the first flight of the Boeing 40-A in 1927, a series of successful light transport aircraft was
                                        built around the basic airframe.  The model 40-B, sub series 4 was probably the most successful
                                        of this breed, and almost every carrier of note operated them in the early 1930s.  The example
                                        shown above was not, strictly speaking, in the service of Boeing Air Transport when this shot
                                        was taken in 1929, but was, by the looks of it, a Boeing demo aircraft (it later did see service
                                        with the Air Transport arm of the company).   Notable difference between the B series and its
                                        forerunner was the increased cabin size, allowing for four, versus two, passengers.