Worldwide, Helicopter Mail, 1931-1954. Extensive collection of covers and much collateral material, featuring autogiro First Flights beginning with 1934 Apex London flights, Airmail Week celebrations from a wide variety of cities and towns in the East Coast, Midwest and West Coast, commencing at Bridgeport, Conn. (home of Sikorsky Helicopter), mostly termed "Experimental Helicopter Service" and "Operated by Army Air Forces", virtually all with special cachets, many with airmail field cancels, many autographed by local Postmasters; various pilots, foreign flights include Canada, England, Netherlands, Belgium, Italy, France, Argentina, Switzerland, Sweden, Germany, etc; collateral material includes picture postcards, newspaper articles, etiquettes, baggage stickers, tickets, and much more; stamps include France #824 1957 Etienne Oemichen deluxe proofs (4 different), Lebanon 1949 C149a UPU souvenir sheet both mint & used; Spain airmails, and much more; closer evaluation will be rewarding. Estimate  $250 - 350. $0