engine L5792DSI was recovered from the World Trade
Center and now sits in the Waukesha Engine Historical
Courtesy of the Waukesha
Engine Historical Society
WAUKESHA — When the World Trade
Center was attacked on 9/11, five Waukesha V12 diesel generating
units kicked on in an attempt to supply emergency power to the
A total of six engines and generators, all of which were assembled
in the Waukesha Engine Factory, were located in sub-basement 6,
which was the lowest level on the west side of Tower One, according
to the Waukesha Engine Historical Society website.
Early videos of the attack suggest the engines and generators may
have only run for a brief period since lights were on in parts of
the building and complex as the towers started to come down,
according to the WEHS website.
The engines weigh a whopping 15 tons each, measuring 18 feet long by
eight feet high and eight feet wide. Five of them were shipped to
New York during the construction of the WTC in the early 1970s while
a sixth was added later on.
As the towers collapsed, a set of Waukesha engines and generators
came online at the Federal Reserve Bank, which is just blocks away
from the WTC. Four Waukesha diesel engine generator packages for
emergency and standby power activated due to the disruption of the
area’s power grid on 9/11.
These engines became the primary power supplier for the next two
weeks while a loyal crew stayed with the engines 24/7, according to
the WEHS website.
On February 26, 1993, a bomb planted by terrorists exploded in the
underground garage of the north tower. Following the bombing, the
units ran for 3 hours and 10 seconds before the generator room
started to fill up with water from broken piping, according to the
After the water rose to the crankshaft centerline area, the engines
were manually switched off. Distributor personnel stayed with the
engines until the water level was too high and then felt their way
to the exit in total darkness, according to the WEHS website.
Of the six engines, three were declared unsalvageable and
immediately scrapped, said Dennis Tollefson, WEHS Board member. Two
are being rebuilt while the sixth engine is held at the Waukesha
Engine Historic Society, Tollefson added.
Unfortunately, the engine is not available to the public due to its
sheer size, Tollefson said. However, the engine has made an
appearance over the years at events such as Waukesha’s Fourth of
July Parade and Veterans Day Parade. The engine was also on display
at the Memorial Center in downtown Milwaukee.
To read more about the Waukesha Engine Historical Society, visit