1950: Junior Chamber International

The first issue for 1950 was a set of five stamps marking the 5th World Congress of the Junior Chamber International held at Manila from March 1 to 8, 1950. These Jaycees stamps were released on two dates: March 1 for the airmails, and March 3 for the three lower values.

Quantities printed:
2c purple (5,000,000)
6c green (4,000,000)
18c blue (3,000,000)
30c orange (5,000,000) airmail
50c red (4,000,000) airmail

1,600,000 of the 18c were surcharged in 1960.

Designer: L. Velasco
Printing method: Engraved
Printers: American Bank Note Company
Perforation measurement: 12
Unwatermarked paper

[Data taken from various sources.]

1948: FAO Conference

FAO stands for Food and Agriculture Organization and a stamp set was issued on February 3, 1948 for the FAO Conference held at Baguio. Printing is rather crude but the design shows farmers threshing rice using a thresher.

Mint copies today can have dark brown to blackish gum (it was made from cassava).

The 40-centavo value is an airmail stamp.

Quantities printed:
2c green and yellow green (572,650)
6c brown and cream (400,000)
18c blue and light blue (300,000)
40c carmine and light pink (199,000)

Printing method: Typographed
Printers: Philippine Bureau of Printing
Perforation measurement: 12-1/2
Unwatermarked paper

Perforation freaks:
2c vertical shifted
2c both horizontal and vertical shifted

Color shift:
2c downward

[Data taken from various sources.]

1947: Quezon-Roosevelt airmails

The first airmail issue of the Republic era came out on August 19, 1947 honoring President Manuel L. Quezon and U.S. President Franklin D. Roosevelt.

Quantities printed:
6c green (600,000)
40c orange (400,000)
80c blue (300,000)

Printing method: Engraved
Printers: American Bank Note Company
Perforation measurement: 12
Unwatermarked paper

If not stored properly, the 40c is prone to oxidation; the orange ink turns to brown and eventually to black.

[Data taken from various sources.]

clipper vinta

Finally, an airmail issue with a design of its own, rather than overprints.

Issued in 1941, the two main subjects are a clipper and a vinta.

These were the last airmail stamps released before the Japanese occupation.

First Airmail Exhibition

Yes, this overprinted stamp for the 1st Air Mail Exhibition is an airmail stamp.

There are two values in the set.

Arnacal

This 3-stamp airmail set commemorated the Manila to Madrid flight by the aviators Antonio Arnaiz and Juan Calvo.

Again, by overprinting previous stamps!

PI-US Initial Flight

This overprint marks the first China clipper flight from Manila to San Francisco.

airmail plane

These airmail stamps were issued in 1933.

The airplane overprint did not commemorate any flight.

Interestingly, an identical overprint was used earlier on Papuan stamps -- in 1930!

Von Gronau

Arrival of Capt. Wolfgang von Gronau was marked by overprinting a set of stamps in 1932.

Von Gronau, a German aviation pioneer, was on a flight around the world in a seaplane.

L.O.F.

The first Philippine airmail stamps were issued during the American administration.

In 1926 a set of stamps was overprinted for the Manila to Madrid flight of two Spanish military aviators. The overprint includes a propeller design.

The next set overprinted for airmail was issued in 1928 for the London-Orient flight of a British squadron of hydroplanes. The two lowest values in this set are shown above.

Wikipedia article

This Wikipedia article about postage stamps and postal history of the Philippines has some interesting facts --


https://en.wikipedia.org/wiki/Postage_stamps_and_postal_history_of_the_Philippines