Originally Posted by
Georgeablelovehowindia
Some 707's had a second HF Antenna (not probe) on the R/H wing to allow a dual HF set-up
BOAC 707-436's for s start used to have them, certainly in the early days. I only know this because I remember it on my Airfix model from 50 years ago!
Boeing 707-436 - BOAC | Aviation Photo #1538434 | Airliners.net