Pennsylvania Railroad
Phase Chart: EMD F2, F3 & F5 Diesel Locomotives

Notes:

1. All F2-F7 Boosters have 3 equally-spaced portholes in the center third panel.

2. While most roads opted for a large, angled number board, the PRR purchased the standard streamlined (small) four-digit numberboard.

3. F3 Phase IIb: Hirsimaki's Black Gold, Black Diamonds, Volume Two indicates (p. 42) that the helper units were not equipped with trainphone antennas. But we know from photo evidence that the units were so equipped, but as delivered did not have trainphone antennas. This initial A-B-A helper demonstrator set was delivered to the PRR in January 1948. They served on the Pittsburgh Division and were retired in December 1962. Also during an overhaul in August of 1956 helper unit 9519A was rebuilt to F-5 specifications with heavier traction motor cables, a prime mover from unit 9782B, and the front replacement porthole panel from a phase 2 F-7A thus eliminating the chicken wire in this area of the carbody. It was reclassified EF15a.

4. F3 Phase IV (F5): For the Pennsy the F-5 units went to work as "Snappers," the F-5 program never impacted the through freight units. Jack Consoli contests the generator as being one of the changes in this phase. However, the fact remains that, for the most part, these units appeared the same externally as the Phase IV's.

5. The InterMountain F3's in Pennsy livery have incorrect (angled) number boards. It is also worth noting that the parts sprue used to manufacture this locomotive also contains the high fans required for a Phase IIa depiction.

Pennsylvania Railroad
Phase Chart: EMD F7 & F9 Diesel Locomotives

Notes:

1. F7s all rated at 1500 hp.

2. Boosters all have 3 portholes instead of louvers.

3. F7 Phase Ia: Initial Pennsy units featured streamlined (small) numberboards. As of July 1949 they switched to the 45-degree, four-digit numberboards. Greg Martin indicates that these units' windshields had raised, exposed gaskets.

4. F7 Phase I Late: The database does not yet contain sub-class designations. All units are currently listed in the initial sub-phase of the main phase designation. I am trying to ascertain which units (if any) came with square end door windows and which came with round end door windows. Photos are few, but there are definitely some with the round window, making them at least Phase Id. It is known that all F7's manufacturered in 1951 and later had round windows. All Pennsy units in this group were delivered in January 1951 and later. The early deliveries would have already been on the assembly line, so it is unknown which window they featured. It is known that all PRR Phase I Late units featured horizontal grills, so their phase is definitely between Ic and If.

5. F7 Phase IIb/IIc: EMD offered a larger dynamic brake package (with 48" fans) but the PRR didn't purchase it.

6. The InterMountain F7 in Pennsy livery features a square window on the rear end door, making it a Phase Ic. I'm told that the parts sprue used in the manufacture of this model also includes a round window door, making a Phase Id depiction possible. It remains to be seen if InterMountain will offer this or not.

Credits

Jack Consoli for considerable clean up and confirmation.