1918, Curtiss Jenny, 16c green and 24c carmine rose and blue, nicely centered, full OG, NH, mostly VF, C.v. $250 (Image)

1973, Progress in Electronics, 11c multicolored, a single with olive color omitted and only traces of vermilion frame are presented, full OG, NH, VF, C.v. $800 (Image)

1978-80, Wright Brothers 31c, three vertical se-tenant pairs with strongly shifted or practically missing colors, in addition Philip Mazzei 40c with red color shifted to the top, full OG, NH, VF, a common stamps are included (Image)

1985, Trans-Pacific Air Mail, 44c multicolored, horizontal imperforate pair, full OG, NH, VF, C.v. $550 (Image)

1989, 20th UPU Congress, Futuristic Mail Delivery, 45c multicolored, top right corner sheet margin se-tenant block of four with ZIP imprint, light blue (engraved) color omitted, full OG, NH, VF, C.v. $475 (Image)

1991, Harriet Quimby, 50c multicolored, left sheet margin block of four, imperforate horizontally, perfect condition, full OG, NH, VF and scarce, C.v. $1,600 as two pairs (Image)

1998, Space Shuttles, imperforate proofs of $3.20 in magenta and $11.75 in cyan, two sets of two values in left sheet margin vertical pairs, printed on coated and uncoated paper, no gum as issued, NH, VF and scarce, C.v. $900 for stamps on uncoated paper, pairs on coated paper are priced with ''-'', Est. $1,000-$1,500 (Image)

1924 (March 17), First Aerial Circumnavigation (First Leg) Flight from Clover Field in Santa Monica, CA to Saint Point in Seattle, WA, stationery postcard 3c red, two confirmation markings on front and Seattle ''MAR.20.1924'' arrival ds on reverse, VF, Est. $300-$400 (Image)

1924 (September 5-28), First Aerial Circumnavigation (Coast to Coast Leg. Atlantic to Pacific) Flight from Boston, MA to Seattle, WA, stationery postcard 1c green, uprated by Franklin 1c green, ''Boston First Landing in US of World Fliers'' machine cancel, all appropriate markings and Seattle ''SEP.28.1924'' arrival ds, VF, Est. $200-$250 (Image)

1924 (March 24), Alaska Pioneer Flight (4th Trip) stationery postcard from Fairbanks to McGrath, ''Aero Mail'' with Wings in red confirmation, pilot Carl B. Eielson signature, the same day McGrath arrival ds, mostly VF (Image)

1931 (January 7-8), First Commercial Trans-Atlantic Flight by Mrs. B. Hart and Lt. W. McLaren with itinerary New York - Bermuda - Azores - Paris, stationery postcard 1c green on leg from NYC to Bermuda, uprated by Bermuda ½c green, appropriate arrival markings and pilot 's sign on reverse, VF, Est. $200-$250 (Image)

1933 (June 10-July 7), First Non-Stop Round Flight to Haiti by ''Columbia'', mixed franking cover, franked by Winged Globe 8c olive bister, specially issued surcharged stamp of 60c/20c blue applied for return flight (Haiti #C4A), tied by Port-au-Prince ''6.JUL.33'', six-line cachet with flight itinerary and crew members, NYC ''JUL.7.1933'' arrival ds, VF, Est. $300-$400 (Image)

1935 (May 20-24), U.S.S. Beaver (AS-5) at Midway Island Navy Mass Flight to Honolulu and Los Angeles, pre-printed cover franked by Special Delivery 16c dark blue, Pearl Harbor ''MAY.24.1935'' transit and Los Angeles ''MAY.30.1935'' arrival ds, signed by pilot, mostly VF, Est. $500-$600 (Image)

1935 (August 20-23), PAA Wake Island - Honolulu Pacific Survey Flight legal size cover, franked by Washington 3c violet, tied upon arrival with Honolulu machine ''AUG.23.1935'' ds, black Wake Island cachet, autographed by PAA official C. Schildhauer on reverse, VF and scarce, Est. $400-$500 (Image)

1938 (May 24), Richard Archbold Trans-Pacific Flight cover carried in the PBY Catalina Flying Boat NC777 ''Guba II'', four-country franking with US, Dutch Indies, Australia and Seychelles, ''Hollandia'' cancellation ''10.5.38'' with month error, signed by Richard Archbold on boxed flight itinerary, backstamped with C.& W. Ltd. ''12.JUN.39'' Cocos, VF, AAMC #867, C.v.$1500 (Image)

1938 (July 10-14), Howard Hughes Record Around the World Flight, specially prepared legal size cover, bearing US, French and Soviet Union air post adhesives, confirmation markings and NYC arrival ds, VF. Howard Hughes' Flight by Lockheed 14 took 91 hours, with stops in Paris, Moscow, Omsk, Yakutsk, Fairbanks, Minneapolis and New York, AAMC #TO1307, Est. $800- $1,000 (Image)

1951, DC-4 Skymaster, stationery envelope 10c chocolate on pale blue paper, error of color, 4-line text on reverse, VF and scarce, a common envelope No. UC16 is enclosed, C.v. $450 (Image)

1951, DC-4 Skymaster, inverted ''REVALUED 6c P.O. DEPT.'' on stationery envelope 5c red, very fresh, unused and VF. This error is listed but priced with ''-'' in the Cat., Est. $800-$1,000 (Image)

Balance of Air Post Collection. 1924-51, six Pioneer Flight covers, arranged on album pages, including Around the World Flight of 1924 (1st landing in Boston), US Catapult 1924-51, six Pioneer Flight covers, arranged on album pages, including Around the World Flight of 1924 (1st landing in Boston), US Catapult Flight to Bremen of 1931, Hungarian FFC from Szeged to Budapest of 1932, New York - Rome Flight of 1935 with Notary Public Seal, unused envelope for Amelia Earhart 2nd Take Off Around the World Flight of 1937, air mail cover from Midway Island, HI to Berkley CA of 1941, in addition two stationery postcards with FD cancel, including color error #UXC1a (C.v. $250), occasional conveyance flaws, F/VF, Est. $500-$600 (Image)

Pioneer Flights. SELECTION: 1927-82, 12 items, including ''Lindbergh Celebration'' St. Louis-Chicago, cover delivered by S.S. Aquitania for Flight London-Munich- Berlin-Vienna of 1928, cover from Boston with portion delivery from Galway to London of 1929 and etc., mainly flawless, F/VF and conservative retail is $250 (Image)

Zeppelin Flights. 1925 (July 4), Airship (Z.R.1) Shenandoah, Governors' Conference Flight, cover sent from USS Patoka to Lakehurst, franked by Washington 2c carmine, circular ''via Air Mail Service USS Shenandoah'' in violet and two-line ''by U.S. Navy Dirigible ''Shenandoah'' in black, next day Lakehurst arrival on reverse, Michel #2, €750, Frost #ZR1-Bb, C.v. $1,000 (Image)

Zeppelin Flights. 1925 (July 4), Airship (Z.R.1) Shenandoah, Governors' Conference Flight, cover sent from Bay Harbor to Lakehurst, franked by Norse-American 2c carmine and black, tied by machine postmark with inverted ''4'', USS Patoka ds, circular ''via Air Mail Service USS Shenandoah'' and two-line ''Via Air Mail by Navy Dirigible'' confirmation markings, Lakehurst ''JUL.5.1925'' arrival on reverse, Michel #2, €750, Frost #ZR1-Bb, C.v. $1,000 (Image)

Zeppelin Flights. 1925, Airship (Z.R.3) Los Angeles Direct and Return Flights to Puerto Rico, five covers, one for direct and four different for return flight, cancelled at San Juan or Mayaguez, bearing different types of confirmation markings, in addition two covers delivered by Graf Zeppelin on different legs of Around the World Flight of 1929, arranged on pages from a Collection, mostly VF, Sieger #20U, T, V, W, 28-29, C.v. €1,100 (Image)

Zeppelin Flights. 1925 (June 6), Airship (Z.R.3) Los Angeles Flight Lakehurst to Minneapolis, cover franked by Norse- American 2c red and black, tied by appropriate Lakehurst machine marking, ''U.S.S. Los Angeles'' confirmation in black, five-lines arrival ''JUN 12. 8.10PM.1925'' date stamp, VF and rare, US Navy Airships did not deliver mail with just a few exceptions, Sieger #20X, C.v. €650 (Image)