Rudder Boost
The Rudder is the only hydraulically assisted primary flight control surface on the B707 and my recollection is that without that assistance available rudder displacement from neutral was approximately halved. The exercise which led to the loss of the RAAF aircraft was not, as I remember, an approved one and was not covered in the Flight Manual.
When the RAAF first took the type into service in 1979 three complete cockpit crews were trained by Qantas using Qantas procedures and Qantas standards. These procedures and standards were used by the initial crews and early pilots and F/E's converted by those initial crews were trained to the same Qantas procedures and standards.
Unfortunately, the system in the RAAF which existed in relation to pilots saw personnel changes on a regular basis and so the experience levels on type as far as pilots were concerned was constantly diluted and the nominated OIC of Training Flight was in the onerous position of having to "get full bottle" in a relatively short time and take responsibility for crew training and maintenance of standards.
The loss of the aircraft and crew was a tragic event but one which was totally avoidable in my view.