In the forty seasons that I've been a fan of auto racing, there have only been twelve American drivers in Formula One.
From 1974 to today ('74 was the first year that Drivers were matched with Race Numbers throughout the whole season):
* Eddie Cheever, # 3 Tyrell
* Danny Sullivan, # 4 Benetton
*
Mario Andretti, # 5
Lotus (the year he won the season)
* Michael Andretti, # 7 McLaren
* Danny Ongais, # 14 Penske
* Brett Lunger, # 18 Surtees
* Scott Speed, # 19, Toro Rosso
* Bobby Rahal, # 21 Wolf
* Mark Donohue, # 28 Penske
* Kevin Cogan, # 51 Ram Theodore
* Peter Revson, # 66 Penske
The only current American Driver in F1 is Alexander Rossi at
Caterham F1 Team, although he is as of the just-finished season a relief Driver and not assigned a number.