Beagle
Here is another reference to their presence that someone forwarded to me:
Eric Waugh, in the Belfast Telegraph on 29 September 2001, reported:
Two RAF officers at a Lincolnshire base, one a senior communications officer, have confirmed that Americans were at the scene of the crash first. When the British servicemen asked them to explain themselves, they were told: "We are looking for something that belongs to us."
You could probably find out for yourself what kind of communication sets were issued to the particular section at the time - a bit outside your comfort zone, is it?