Smoke Extractor

In 1926, Minneapolis Fire Chief Charles Ringer and the Minneapolis Fire Department Repair Shop designed and built a “Smoke Extractor”, forerunner to today’s exhaust fans carried by most truck (ladder) companies for the ventilation of smoke and gases from burning buildings.  The first version built used a PTO from the chassis drive train to power a “fan” that was equipped with only one suction intake and provided a displacement of only 5,000 cubic feet per minute.  Subsequent modifications by the Repair Shop over the next four years to increase displacement capability, with testing by University of Minnesota engineers, finally produced the machine described below.

The “Smoke Extractor” consisted of a 48-hp dual valve converted 1920 Pierce Arrow touring car chassis (#515465) with extended frame, jack shafts, and chain drive.   A Sturtevant Fan, Multi-vane, Design 3, Size 26, Extra Heavy, wheel diameter 26¼-inches, weight 1,000 lbs., was mounted on the frame.  This fan was direct driven by a Model A Ford engine governed at 1,250 rpm.  The extractor carried four 14-inch by 10 ft. flexible steel suction tubes along with several door and window coverings made of heavy wire netting and asbestos cloth with a 14-inch hole in the covers to receive the 14-inch flexible steel tube.  The “Smoke Extractor” was able to displace air, smoke or gases at the rate of approximately 20,000 cubic feet per minute.

Two of the photos show how it appeared in 1930 when the final product made its debut on the Pierce Arrow chassis.

Over the years, even though its conveyance had changed,  the “Smoke Extractor” itself remains as described with its fan being driven by a Model A Ford engine.

1926 – 1935    1920 converted Pierce Arrow (#515465)

1935 – 1949    1935 Ford truck chassis (#2210568)

1949 – 1952    MFD shop-built trailer (towed)

1952 – Today  1952 Ford COE truck chassis (#42849)

Smoke Extractor on the 1920 converted Pierce Arrow touring car chassis

On the 1935 Ford chassis

On the 1952 Ford chassis

The “Smoke Extractor” remained on the MFD’s apparatus roster until the mid-to-late 1970’s when it was retired.