By Wayne Bailey
February 2010

Planning Session: Dak Crew: L to R Bob McElman, Eric Welin, Brian Troniak,
Doc Mckiel, Dave Richards.

Steady progress is being made on the Dak # 655B, and now that the rebuild on the centre section has been finalized and married to the fuselage, work has shifted to other facets on the project. Bill Flynn and Russell Keddy have removed and reinstalled many of the fuselage panels. A tedious process that involved removing many badly corroded and rusted screws and replacing them with new fasteners. Bob McElman, Chuck Calder, and Doc Mckeil have made the horizontal and vertical stabilizers ready for installation of the rudder and elevators that are waiting to be converted from fabric covered to aluminum. In future the Dak will be on static display, outdoors in the Museums Airpark, which necessitates various modifications to the control surfaces and many openings and vents. Our project leader Eric Welin has been busy with sheet metal repairs and modifying the engine nacells to install the turbo superchargers cover panels, which were part of the original aircraft engine package. The two "new guys" Brian Troniak and Dave Richards, a couple of folks borrowed from the Bolingbroke project, have been steam cleaning, sand blasting and doing a cosmetic overhaul on the Pratt and Whitney R1830 engines, prior to their installation. Many thanks to the A.M.S.E. folks in 14 hangar for their help on this part of the project.

A little history on the R1830s thanks to the Pratt and Whitney info site and utilizing the Wickipedia encyclopedia and its G.N.U. Free Documentation Licence.

The Pratt and Whitney R1830 Turbo Wasp is a two row 14 cylinder air cooled radial that first saw the light of day in 1931.At 1830 cu inch or 30 litre the first series or Dash numbers, produced about 800 H.P., but later versions, thanks to turbo superchargers, upped the power to 1200 H.P. which helped greatly with the takeoff weights and service ceilings. During WW2.the Dak/DC3/C47Skytrain made many trips and played a big part in the operation flying much needed supplies over the Burma Hump, a route that was flown well over 13000 feet. The engines in our Dak are the Dash 90/92 series that were manufactured, in wartime by Buick were of the higher horsepower version. This gave them a power to weight ratio of 0.96 H.P. per lb. Compared this to the turbo compound on the Argus which is 0.82 H.P. per lb, and to the Allisson T56 which is 2.75 H.P. per lb. A testament to engineering advancement and metallurgy. The Pratt and Whitney 1830 was used in 25 different aircraft, most notable were the B24 Liberator, F4FWildcat, PBY Catalina and of course the C47 Skytrain/DC3. All told, there were 173, 618 of the 1830's built at various facilities. A most notable figure that makes it the most produced a aircraft reciprocating engine ever produced.

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