Steve,
From the US Pilot-Controller's glossary:
PAN-PAN- The international radio-telephony urgency signal. When repeated three times, indicates uncertainty or alert followed by the nature of the urgency.
So, IAW it would be: "Pan Pan, Pan Pan, Pan Pan ... message."
Now, being realistic, on a congested freq, I'd go for "Mayday, Mayday, Mayday" - shorter syllables and gets off the toungue quicker eh?
[ 09 January 2002: Message edited by: RW-1 ]</p>