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PERMANENT PICKUP ROUTES
ESTABLISHED
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Under the plan for permanent routes, the Civil Aeronautics Board (CAB) would be the contracting agency rather than the Post Office Department. Routes would be ex panded from two to five, serving all of the original destinations as well as over SO more. Radiating a total of 1,380 miles from the Pittsburgh hub, two routes would be to Huntington, West Virginia, with others being to Jamestown, New York; Williamsport, Pennsylvania; and Philadelphia, Pennsylvania. Communities in six states with populations of 800 to 120,000 thus would be served. Despite the one year demonstrated success of the trailing grapple pickup system, it became increasingly evi dent that a further improved method was necessary. Under the existing means, holding optimum altitude in heavy turbulence was difficult, some times resulting in a miss at capturing the horizontally stretched transfer rope. A miss of an inch required a circle to try again. Further, in bumpy air, the 8-pound grapple would some times swing laterally to collide with the wooden markers atop the poles, damaging them or even breaking the cable. NEW PICKUP SYSTEM DEVELOPED
Work on an entirely new system had been in progress at All Ameri can's experimental shop at Wilmington, Delaware, so, in agree ment with the CAB, service to new destinations would be delayed until planes were provided with new equipment and totally different ground facilities were in place. The Stinsons would be fitted with re tractable IS-1/2-foot long, 2-inch diameter ash booms to be positioned for pickup at a 4S-degree angle with a single prong hook at the lower end
(Graphic 4). A completely new con cept, a compact mechanism consisting of reel, brake, and electric motor, wou ld be mounted at the hatch on the floor of the aircraft. Forty feet of 3/8-inch diameter nylon rope connected reel and hook. Ground stations would, likewise, be much different. Gone would be the tall, husky steel poles. In their place would be portable, small-diam eter aluminum tubes tipped by short lengths of bamboo. Set upright in ground receptacles, they would be 20 feet tall, which would later be re duced to 12 feet, and 20 feet apart. Small orange canvas triangles with wire hitch pins would hold aloft a loop of 3/8-inch diameter nylon rope attached to the delivery con tainer situated on the ground between the poles. The 28-inch tall delivery contain ers remained unchanged. To protect the contents, each had a thick fiber dome and a vulcanized rubber skirt as well as an internal canvas bag with a closure strap. Patent records credit Stuart Plum mer as the inventor of this radically changed system, which enabled pi lots to approach pickup stations with greater accuracy and higher speeds . With the incoming delivery trailing above and behind the extended hook, the pilot would release the rope with bag about 200 feet before reaching the upright poles. Once the boom contacted the nylon transfer rope, causing it to pull free, the rope would slide down the boom to disen gage the hook. Under the strain of lifting and accelerating the outgoing load, the nylon ropes stretched; con currently, rope briefly played out from the reel while an automatic brake smoothly stopped the unwind. Once the flight mechanic assured there was no fouling, an electric mo tor was activated to draw the
container close; the last short dis tance to bring the bag through the hatch was by hand. Using nylon rope in this process was critical since under stress of pickup the nylon elongated somewhat without rapid recoil. That rope stretch, reel un wind, and smooth braking so effectively dissipated energy and strain that capturing a load was barely felt by the flight crew. Within months all the Stinsons were fitted with the new equipment. Then, because of higher allowable pickup speeds, schedules, terminal to-terminal, were shortened. The allowable total weight of regular and express mail to be placed in the bag was increased to SO pounds. Flight crews as well as station attendants found this new system to be a vast improvement. CAB PROPOSES WEATHER RESTRICTIONS
Once under CAB administration of the contract, some flight rules were imposed. A minimum ceiling of 500 feet and 1 mile of visibility as viewed from the cockpit was to be observed. En route, if atmospheric conditions became worse and pilots had to pull up on instruments to re turn to base, that action had to be justified with a letter of explanation. By "liberal/l interpretation of ob served weather, pilots found it unnecessary to write many letters. Decades later Captain Lloyd Sant myer reflected, ''If we had followed those rules, we would have been bankrupt in one year./I In plying their routes, there were countless in stances when crews pushed the limits of "contact flying" to get their jobs done. DR. LYTLE S. ADAMS DEPARTS
During its first year, All American had notable success in fulfilling its VINTAGE AIRPLANE 9