FM P-12-42

Infobox Locomotive
name=FM P-12-42
powertype=Diesel-electric
gauge=4 ft 8½ in (1435 mm)

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caption=An FM P-12-42, Boston and Maine Railroad #1.
builder=St. Louis Car Company
aarwheels=B-2
cylindercount=8, Opposed piston
primemover=
builddate=1957–1958
totalproduction=4
locale=North America
collectionmethod=3rd rail (NH only)
electricsystem=660 V DC (NH only)
poweroutput=1,200 hp (895 kW)
topspeed=117 mph (188 km/h)
weight=200,000 lb (90,700 kg)
tractiveeffort=50,000 lbf (222 kN)
length=60 ft 0 in (18.28 m)
enginetype=Diesel
aspiration=
cylindersize=
displacement=
transmission=DC generator,
DC traction motors
locobrakes=Straight air
trainbrakes=Air
buildmodel=P-12-42
railroad=Boston and Maine Railroad,
New Haven
disposition=None

The P-12-42, also known as the "Speed Merchant," was a streamlined, 1,200 hp locomotive built between 1957–1958 by Fairbanks-Morse, specifically to operate on each end of the Talgo train produced by American Car and Foundry. This model represented F-M's attempted entry into the lightweight locomotive market, but only four of the low-slung units were produced: one pair was purchased by the Boston and Maine Railroad, while the other set went to the New York, New Haven and Hartford Railroad.

The P-12-42's eight-cylinder opposed piston engine was normally rated at 1,600 horsepower after 1950, but was derated due to train lighting and other ancillary loads ("hotel" power). The 100-ton units measured 60'-0" long by 10'-6" wide by 12'-0" high, and were configured in a B-2 wheel arrangement mounted atop a pair of two-axle AAR road trucks, geared for 117 mph with only the first two axles powered. The P-12-42 was one of the first locomotives to have its prime mover configured to run at a constant speed, with traction generator output regulated solely by excitation. The New Haven locomotives were dual-powered, and came equipped with third-rail pickups to allow them to operate in New York's Grand Central Terminal (the first dual-power locomotives light enough to operate on the Park Avenue viaduct). In addition to articulated units, the P-12-42 could haul Budd's "Pioneer III" passenger cars as well.

F-M expected to sell many more units to the New Haven (perhaps in a Train Master-style carbody), though the NH ultimately opted to purchase a fleet of sixty EMD FL9s instead.

References

*

Further reading

* — also covers the P-12-42.

ee also

* List of Fairbanks-Morse locomotives

External links

* [http://www.nhrhta.org/images/ne5_5.gifMagazine advertisement from late 1955 depicting an artist's rendition of the New Haven's "John Quincy Adams" Talgo train]
* [http://www.nhrhta.org/images/ne5_6.gifLate 1955 magazine advertisement depicting the Fairbanks-Morse "Speed Merchant" locomotive]