<sod>During this period CARDE was visited by a US team, including Lieutenant General [[Arthur Trudeau]], who was impressed with Bull's work. Trudeau was director of US Army Research and Development, and he quickly set up a similar effort at the [[Aberdeen Proving Ground]] under the direction of Dr. Charles Murphy. They built an analog of Bull's gun using a {{convert|5|in|mm|sing=on}} gun and started test firing it over the Atlantic in 1961. The team used a fire-control radar from a [[Nike Hercules]] missile battery to track the shells, which released a cloud of [[Chaff (countermeasure)|chaff]] at altitudes up to {{convert|130000|ft|m}}.{{citation needed|date=December 2014}}<eod>
<sod>During this period CARDE was visited by a US team, including Lieutenant General [[Arthur Trudeau]], who was impressed with Bull's work. Trudeau was director of US Army Research and Development, and he quickly set up a similar effort at the [[Aberdeen Proving Ground]] under the direction of Dr. Charles Murphy.{{Who}} They built an analog of Bull's gun using a {{convert|5|in|mm|sing=on}} gun and started test firing it over the Atlantic in 1961. The team used a fire-control radar from a [[Nike Hercules]] missile battery to track the shells, which released a cloud of [[Chaff (countermeasure)|chaff]] at altitudes up to {{convert|130000|ft|m}}.{{citation needed|date=December 2014}}<eod>