An underground rocket or rocket drill is a device for rapidly drilling holes through soil and rock of varying composition at rates up to 1 metre per second by utilising supersonic jets of hot gases. It was developed by Russian engineer Mikhail Tsiferov in 1948. Proposed uses for the device included drilling shallow. .
Further development led to the first prototype, built in 1968. The device consisted of a cylindrical shell filled with solid propellant, with. .
• Жолондковский, О. (1966). [Underground voyage of fiery endmill]. (in Russian) (12).• .
SolidThe solid fuel version of the device was limited by the volume of propellant it could carry, which was sufficient for 5 to 20 seconds of operation, enough to create a well up to 20 metres deep. The inventor saw further.
[pdf] Drilling at Kola SG-3 began on 24 May 1970 using the -4E, a serial drilling rig used for drilling . The rig was slightly modified to be able to reach a 7,000-metre (23,000 ft) depth. In 1974, the new purpos. .
The stated areas of study of the Kola Superdeep Borehole were the deep structure of the , discontinuities and the thermal regime in the Earth's crust, the physical and chemical compositio. .
The drilling ended in 1995 due to a lack of funding. The scientific team was transferred to the federal state unitary subsidiary enterprise "Kola Superdeep," downsized, and given the new task of thoroughly studying th. .
• The United States had embarked on a similar project in 1957, dubbed , which was intended to penetrate the shallow crust under the Pacific Ocean off Mexico. After initial drilling, the project was aband.
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