All she wrote. On June 16, 2012, shortly after 08:00, ALTO and SLOPE were removed from service and the new interlocking of COVE Jct and ALTOONA were put in effect. At 12:03 the block operator was officially relieved of duty and left the building. The photo above was taken in July 2011, when the project was still in the planning stages. A 4-banger set of helpers had just cut off the rear of a 534 coal train and received permission from the operator to procede.
ALTO tower, placed into service in September of 1915, replaced the original structure in downtown Altoona known as “17th street interlocking” which was built in 1890. By 1917 the interlocking was referred to as “JK” tower based on its telegraph code. On February 19, 1942 the name of JK tower was changed to ALTO, an abbreviation of Altoona.
The primary reason for the new structure in 1915 was to house a US&S early model 14 27-lever electro-pneumatic interlocking machine. Several modifications in 1933, 1934, and 1965 saw the addition and removal of various interlocking machines from other closed towers in the area. In 1973 a new 15 station/30 lever CTC panel was installed to control WORKS, HOMER, and ROSE. In 1981 the 15 station/30 lever CTC panel was removed and replace with a new 30 station/60 lever panel that included an additional remote interlocking called ANTIS.
History of ALTO tower from text by Thomas Kozub.