1926 (November 26), Africa Flight registered cover from Zurich to Egypt, franked by four stamps, black boxed confirmation marking, Alexandria "3.Dec.26" arrival ds is alongside, undelivered and returned to Switzerland on December 21, appropriate hs on reverse, mostly VF and scarce, Est. $300-$350

150.00

1930 (December 2), registered cover delivered by Ad Astra Aero Africa Flight on leg Zurich - Cartagena - Alicante, franked by three stamps, blue confirmation cachet, undelivered and returned to Fribourg on December 11, appropriate markings on front and reverse, F/VF

75.00

1931 (October 17-28), 3rd SA Round Flight stationery unsevered reply card 20(c)/25(c)+20 (c)/25(c) uprated for direct flight by two Swiss stamps, bearing Friedrichshafen "17.10.31" connection and green Flight marking, Pernambuco "20.X.31" receiver; reply portion bearing two Brazilian adhesives, violet confirmation and Friedrichshafen "28.10.31" arrival ds, VF and scarce, Sieger #133 var, Est. $300-$400

150.00

1932 (July 30-31), Danzig Flight stationery postcard 10(c) red, uprated by two German adhesives, tied by Friedrichshafen "30.JUL.32" connection marking, blue Flight cachet and Ronne "31.7.32" arrival ds, VF and scarce, Sieger#169 var, Est. $150-$200

75.00

1933, two postcards of Germany (May 1) and Switzerland (July 18) Flights, franked by one or three stamps respectively, each one with appropriate green Flight marking, Friedrichshafen "1.5.33" and "18.7.33" arrival ds, both are VF, Sieger #201, 222, Est. $200-$250

100.00