For an airplane or a helicopter to “land on a postage stamp” is to land in a small area. New York’s LaGuardia Airport has been said to be a postage-stamp sized airport. Landing on an aircraft carrier is also said to be like “landing on a postage stamp.”
 
“British Have An Airplane That ‘Can Land On a Postage Stamp’” was a newspaper headline in August 1926. “Give ‘em (army fliers—ed.) a chance to make good that boast about landing on a postage stamp” was cited in print in 1934.
 
 
24 August 1926, Trenton (NJ) Evening Times, pg. 2, col. 6:
British Have An Airplane That
“Can Land On a Postage Stamp”
 
Google News Archive
13 February 1934, Palm Beach (FL) Daily News, “Everything’s Up in the Air” by Arthur “Bugs” Baer, pg. 1, col. 2:
Army fliers are packing the mail bags today. Give ‘em a chance to make good that boast about landing on a postage stamp.
 
Google Books
On Secret Service
By Leonard Gribble
London: Burke
1946
Pg. 26:
They had to be able to pick out a landing-field in a confusion of shadows, and, as one of them put it, “land on a postage stamp.”
 
Google News Archive
4 December 1963, Ocala (FL) Star-Banner, pg. 25, col. 3:
“Like Landing On A Postage Stamp”
NEW YORK (AP)—“It was like landing on a postage stamp,” said Stanley Szycher, 42, pilot of a helicopter that made a forced landing atop a Manhattan meat company plant Tuesday.
 
Google Books
Earthly Remains:
A Novel
By Peter Hernon
Secaucus, NJ: Carol Pub. Group
1989
Pg. 160:
“Not good at all. Putting a DC down on this runway would be like landing on a postage stamp.”
 
Google Books
Damn the Torpedoes:
My Fight to Unify Canada’s Armed Forces
By Paul Hellyer
Toronto, Ont.: M&S
1990
Pg. 58:
Anyone who hasn’t shared this experience can imagine that it’s like landing on a postage stamp in the middle of the Atlantic. What if the plane isn’t lined up perfectly with the deck? What if the tail is too high and the hook misses the arresting cable? What if either the hook or the cable should break?
 
Google Books
Far Away in the Sky:
A Memoir of the Biafran Airlift
By David L. Koren
CreateSpace Independent Publishing Platform
2011
Pg. 133:
“This was easy,” said Delahant,  “compared to landing on the pitching deck of an aircraft carrier. That was like landing on a postage stamp in the ocean.”
   
JetHead
Why you should NEVER fly into Washington National Airport
This entry was posted on December 24, 2011 at 11:31 am
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1. The Postage Stamp Effect: like LaGuardia in NYC, the airport was built in the early days of commercial aviation, when the defining factors in aircraft design were slow air speeds, light weights, agile propeller aircraft. Fine.
 
Maneuvering this thick-winged, lumbering prop job on final was routine at a relative crawl compared to today’s heavier swept wing jets, which need lots of room in the air and on the ground to operate safely. But Washington National is a postage-stamp sized airport from a bygone era, and the serpentine “approach” hasn’t changed: ...
   
Just Urbanism
APR 05 2012
NEXTGEN IS NICE, BUT IT WON’T NECESSARILY REDUCE FLIGHT TIME
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And constrained they are, especially on postage-stamp sized airports such as La Guardia which have limited runways, taxiways and gate areas.