The B-17s were Israel's only heavy bombers in the 1948 war
US President George W Bush has granted a rare posthumous pardon to a man who broke the law to supply aircraft to Jews fighting for the state of Israel.
Charles Winters served 18 months in prison for violating the US Neutrality Act by helping to deliver in 1948 two converted B-17 Flying Fortress bombers.
In 1961, then Israeli Foreign Minister Golda Meir commended Mr Winters for his contribution to her country's survival.
Two others convicted with him in 1949 were pardoned by previous presidents.
President John F Kennedy pardoned Herman Greenspun in 1961, and President Bill Clinton pardoned Al Schwimmer in 2000. Mr Winters died in 1984.
In the summer of 1948, Charles Winters worked with the two men to transfer to Israel two B-17s that he had converted for use in his Florida fruit business.
Winters flew one of the two aircraft himself to Czechoslovakia, where they and a third B-17 were retrofitted to be bombers before being flown to Israel.
The three aircraft were the only heavy bombers in the Israeli Air Force, and historians say they helped turn the 1948 war against Arab armies in Israel's favour.
Mr Winters, a Protestant, was hailed a hero in Israel, but in the US he was later convicted of conspiracy to export and the exportation of a military aircraft to a foreign country.
The posthumous pardon for Mr Winters - only the second ever granted by a US president - came after a lengthy campaign by his son, Jimmy.
"I'm overwhelmed," he told the Associated Press.
Golda Meir commended Mr Winters for his contribution to Israel's survival
"It happened 16 years before I was born. He went to jail and he didn't want his kids to know. He was old-school and proud."
Jimmy Winters said he first learnt of his father's famous past after seeing an outpouring of gratitude from the Jewish community after his death in 1984.
His mother, Joan, was flown to Israel, where she buried half his ashes at a Christian cemetery near the Jewish cemetery of the Knights Templar in Jerusalem. The other half were scattered from the top of Mount Tabor.
The Hollywood film director, Steven Spielberg, was one of the many people who wrote a letter to President Bush in support of a pardon.
"There are probably many unsung heroes of America and of Israel, but Charlie Winters is surely one of them," he said.
Mr Winters was among 19 people granted pardons by President Bush ahead of the Christmas holidays. A 20th person had his prison sentence commuted.