Operation Distant Plain

Operation Distant Plain was a series of non-nuclear explosive and detonable gas tests performed on test sites in Alberta, Canada, during the course of 1966 and 1967. Their purpose was to provide airblast, cratering, and ground shock data in summer and winter conditions for testing new prototype equipment, military targets and coniferous forest blowdown, and defoliation.

Operation Distant Plain
125 foot 20-short-ton (18 t) propane-oxygen hemisphere is prepared for detonation as Event 2A. The striped poles carry instrumentation equipment and a human figure can be seen in the lower right.
Information
CountryCanada
Test site
  • Suffield Experimental Station, Alberta
  • Hinton, Alberta
DateJuly 7, 1966 – August, 1967
Number of tests8
AgencyDefence Research Board, TTCP
ExplosiveTNT, Detonable Gas
Configuration
  • Stacked Sphere (Tower, Buried)
  • Stacked Hemisphere
  • Gas Balloon
  • Gas Hemisphere
Max. yield100 tons of TNT (420 GJ)
Test chronology

Participants included Canada, the United Kingdom, Australia, and the United States under the Tripartite Technical Cooperation Program.[1] Detonable gas balloons were used in this operation in an attempt to find an economical substitute for TNT as well as for the fact that they could be placed at desired heights without a heavy support structure or towers. In addition, they were more adaptable to airblast phenomena and produced a well defined blast wave without perturbation or ejecta; they also produced no crater. However, it was found that they lacked the high pressure associated with high explosives, and difficulties were encountered as the 20-ton gas balloon ruptured and another detonated unexpectedly during inflation. Ultimately ANFO was elected as a lower cost alternative to TNT for non-nuclear explosives tests.[2][3]

Tests

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The following table summarizes the events that took place during the operation in chronological order.

Event Date Charge Yield (short tons) Height of Burst (feet) Location Notes
1 7 July 1966 TNT sphere, tower 20 85 Drowning Ford Test Range, SES Airblast and induced ground motions
2 July 1966 125 foot methane-oxygen balloon 20 85 Drowning Ford Test Range, SES Cancelled, balloon ruptured during inflation
2A 22 July 1966 125 foot propane-oxygen hemisphere 20 0 Drowning Ford Test Range, SES Test feasibility of detonable gas, compare with 20 ton TNT events
3 27 July 1966 TNT sphere, half buried 20 0 Drowning Ford Test Range, SES Normal environment control for Event 5
4 16 August 1966 TNT Hemisphere 50 0 Edson Forest, 10 miles northwest of Hinton Coniferous forest blowdown test
2B October 1966 125 foot methane-oxygen balloon 18.6 63 Drowning Ford Test Range, SES Rescheduled Event 2, detonated unexpectedly during inflation on ground
5 9 February, 1967 TNT sphere, half buried 20 0 Drowning Ford Test Range, SES Frozen ground test
6 26 July 1967 TNT sphere, supported 100 0 Watchdog Hill Blast Range, SES Nuclear weapon surface burst simulation
1A 18 August 1967 TNT sphere, tower 20 30 Watchdog Hill Blast Range, SES Airblast and induced ground motions, repeat of event 1

References

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  1. ^ Kelso, J. R.; Kingery., C. N.; Choromokos, J. Jr. (1 January 1966). "Operation Distant Plain. United States Participation With Canada, Australia, And Great Britain In a Non-Nuclear Experimental Test Series". Defence Technical Information Center. Retrieved 19 May 2017.[dead link]
  2. ^ Ingram, James K. (1 May 1971). "Operation Distant Plain, Events 1, 2A, 3, 4, and 5: Project 3.02A, Earth Motion and Stress Measurements". Defence Technical Information Center. Archived from the original on June 2, 2018. Retrieved 19 May 2017.
  3. ^ Ralph E., Reisler; Noel H., Ethridge; Daniel P., LeFevre; Louis, Giglio-Tos (1 July 1971). "Air Blast Measurements from the Detonation of an Explosive Gas Contained in a Hemispherical Balloon (Operation Distant Plain, Event 2a)". Retrieved 19 May 2017.[dead link]