Did you know…
Did you know the Shah's Iran bought second-hand 747s from TWA and Continental?
Short answer
Yes: on 1 February 1975 TWA announced the sale to the Iranian government of six of its nineteen Boeing 747s for $99 million. It ended up handing over nine to the Imperial Iranian Air Force in order to cover its payroll. With three more aircraft from Continental, Iran assembled twelve jumbos.

A sale born of a cash shortfall
On 1 February 1975 TWA announced the sale to the Iranian government of six of its nineteen Boeing 747s for a price of $99 million. At that same date the Iranians were also negotiating for six more of the company's jumbos. The airline was forced to sell nine of its 747 fleet to the Imperial Iranian Air Force in order to cover payroll commitments. Those aircraft left the fleet between March and December 1975.
Twelve jumbos from two US airlines
Of the twelve 747s the IIAF bought, nine came from TWA and three from Continental. Only ten of them had the SCD modification.
Jumbos in uniform
The Islamic Republic of Iran Air Force, formerly the Imperial Iranian Air Force, was the only air force in the world with a dedicated fleet of 747 freighters. The 747 also served as the basis for several government and military variants, such as the VC-25, the aircraft known as Air Force One. These versions are typically used to transport government officials and other dignitaries, although the United States Air Force has given them other uses with purpose-built variants, such as the E-4B airborne command posts.
More questions

Foto: 4300streetcar (CC BY 4.0) Commercial aviation
Which 747 carried Enterprise "piggyback"?
The first Shuttle Carrier Aircraft was a Boeing 747-123 registered N905NA, originally built for American Airlines and acquired by NASA in 1974. Boeing… more…

Commercial aviation
Was there an amphibious DC-3?
Yes: the Douglas XC-47C was created by fitting Edo Model 78 floats onto a standard C-47. The single-step metal floats carried retractable wheels that also… more…
_Berliner_Luftbr%C3%BCcke.jpg)
OTFW, Berlin (CC BY SA), vía commons Commercial aviation
Was a C-47 converted into a glider?
Yes: the Douglas XCG-17 was an assault glider created by converting a twin-engine C-47 Skytrain during World War II. Its engines were removed and the nacelles… more…

Commercial aviation
What did the USSR build from the DC-3?
The USSR built a version of the DC-3 under a licence granted to its government on 15 July 1936. It was designated PS-84 and, in 1942, renamed Lisunov Li-2… more…

Commercial aviation
What was "Puff, the Magic Dragon"?
It was the nickname of the Douglas AC-47 Spooky, the first in a series of fixed-wing gunships developed by the United States Air Force during the Vietnam War… more…

Commercial aviation
How did the RAF refer to the C-47?
The RAF called it Dakota: the Dakota I was the designation for 53 C-47s received under Lend-Lease. The Dakota III designated 962 C-47A Skytrains. The Dakota… more…