EMD F2-F3-F5 Phase Chart

Phase Chart:
Santa Fe EMD F2, F3 & F5 Diesel Locomotives

***All Phases here include rectangular-slit type dynamic brakes on both cabs and boosters***
Designation	F2	F3 Phase1	F3 Phase 2 Early	F3 Phase 2 Late	F3 Phase 3	F3 Phase 4	"F5"
Dates	Jul 46 to Dec 46	Nov-Dec 46>>	Feb-May 47>>	Dec 47-Apr 48>>	Mar-Jun 48>>	Aug-Nov 48>>	October 48 to Feb 49
Radiator Fans	High, flat-top 36"			Low-pan-top 36"
Top-third panel	Chicken Wire in openings only		Full Chicken wire at top third panel			Horizontal Stainless Steel Grille
Rear vent opening	Short		Long
Center-third panel	Three equally-spaced portholes		Chicken wire between two portholes covering 4 rectangular openings		4 horizontal louvers between two portholes
Electrical	Same as FT	D17 traction motors					D27 traction motors w/heavier cables
Number Boards	Same as FT	Large, mounted on nose
Original ATSF Numbers & Liveries	none	16-21 Long Warbonnet & Aluminum Paint	none	none	22-30 Short Warbonnet, Stainless Steel Panels	none	31-36 Warbonnet 200-201 Catwhisker

All F2-F7 Boosters have 3 equally-spaced portholes in the center third panel.
ATSF 16-21 modified in 1948 to Phase 2 (Early) appearance.
ASTF 22-30 and 31-36 upgraded to vertical grilles 1951/52. The 22-30 units are most likely to have received grilles sacrificed by the 260-267 freight units.
By 1953, ATSF 16-21 upgraded to vertical grilles and horizontal or vertical louvers. They retained their long warbonnet livery through these upgrades, but none of this group would survive to be renumbered into either the 300 or 325 classes. The last of this group was retired in 1972.
The short warbonnet styling first displayed on units 22-30 would set the standard for all future passenger and dual-service F-unit deliveries.

Chart developed by Jim Fuhrman with details supplied by Ed Hawkins and John Thompson.