This plot is commonly referred to as either “Open Travelers” or “Invisible Palm Aces”. The effect is a minimalistic interpretation of the Ace Assembly, where the traditional twelve indifferent cards are disposed of and only the four Aces are apparently in use.
The plot was originated by William Miesel, who published his “Invincible” in The New Phoenix, No. 362, Oct. 1961, p. 277. The “Open Travelers” title came courtesy of Edward Marlo who published his version of the plot under that name in The New Phoenix, No. 375, Dec. 1962, p. 329. Marlo didn't credit Miesel, instead claiming that the idea stemmed from private correspondence with Neal Elias in 1955.
From this point, various handlings and methods were devised. From these controversy has arisen.
The first variant to hit print is “Face-up Flyers” from Epilogue, No. 4, Nov. 1968, p. 27. Both Bruce Cervon and Dai Vernon share the byline. This ushered in the use of tent vanishes in Open Travelers routines. Cervon has stated that the problem of doing an assembly with only four Aces was posed to him by Vernon, along with the suggestion of using the tent vanish. From this Cervon devised the construction of “Face-up Flyers” (for citations of Cervon's claim, see his e-mail defense below). Cervon recorded his earliest attempt at the plot in an Aug. 22, 1966 entry to his notebooks. This can be seen in Bruce Cervon's Castle Notebooks, Volume 3, 2008, p. 107. In a letter to Genii, Vol. 51 No. 10, Apr. 1988, p. 604, Cervon claims he had no knowledge of Miesel's “Invincible” before publishing “Face-up Flyers”.
The following year, Cervon published another version, “Aerodynamic Aces”, in Perpetual Motion Poker Routine, 1969, n.p. (later reprinted in The Cervon File, 1988, p. 41). This saw the first instance of the “invisible palm” presentational hook. The same year, Larry Jennings published “Jennings' Open Travellers” in Alton Sharpe’s Expert Card Mysteries, 1969, p. 41. Jennings also uses the notion of invisibly palming the Aces in his presentation.
Cervon and Jennings were peers at the Magic Castle during this time period. Neither claim independent invention; both claim theft by the other. The story separates into two conflicting arguments:
For Jennings's side: In Jennings '67, 1997, p. 156, Jennings talks in depth about his version of events. He claims that Vernon's challenge to Cervon came after seeing Jennings's routine, and that Alton Sharpe had seen it and asked to publish the trick several years prior to Cervon's version seeing print. Jennings believed that Cervon did not deserve credit for the effect.
For Cervon's side: In direct response to the claims made by Jennings and Richard Kaufman in Jennings '67, Cervon sent out private email correspondence restating his claim to the method and “invisible palm” presentational ploy, and that Bill Miesel and Dai Vernon should be credited for the effect. Cervon claims that Larry Jennings saw him perform the ending of his “Aerodynamic Aces” at a local club meeting and then questioned other attendees about what happened during the rest of the trick.