Grand Slam

Grand Slam is an earthquake bomb or ammunition model.

Also recorded as Bomb, Medium Capacity, 22,000 lb.

In detail

It is associated with United Kingdom. The record gives 1943 as its date of establishment or first appearance.

Sources

Each source is named with the standing the house places on it, so the evidence can be weighed rather than taken on trust.

reference work · Reputable secondary · Wikipedia
“Grand Slam (bomb)”, English Wikipedia, consulted as further reading
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reference work · Reputable secondary · Wikidata
Wikidata, structured authority record Q1366888: Grand Slam
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