The Heuer Autavia 3646 was manufactured with three different dial variations:
- Large registers, with luminous index marks and luminous 12 and 6 numerals, known as the “1st execution” dial. This dial came in both a 30 (early serials) and 45 minute counter. There is an inverted luminous triangle mark above the 12, and a luminous triangle under the 6.
- Small registers, with applied steel index marks and lume plots for hours, with a thick index mark and two plots at 12. This 2nd execution dial came only with a 45 minute counter.
- Small registers, with applied steel index marks and lume at the edge of the steel marker. This 3nd execution dial came only with a 45 minute counter.
We do see a couple of pieces that do not align with the rest of the 1st-3rd execution dials known:
- Dial with ‘T’ in silver print above ‘SWISS’ on the lower half of the dial
- Dial with ‘FAB. SUISSE’ about ‘SWISS’ on the lower half of the dial.
I do not know when this additional text was added, at time of manufacture or later, but collectors should note that these are the only pieces known with text aside from the standard “SWISS” only text at 6 o’clock.