Vmca
Very sadly, those who know of the events leading to the loss of A20-103, a Boeing B707-300 operated by 33 Sqn RAAF, know very well the meaning and implications of Vmca.
Much comment, often misguided, has been on this forum and others over time. As pointed out by Pattern is Full Vmca is that speed below which directional control of the aircraft cannot be maintained with full rudder deflection. For some of we older folk things such as "Dutch Roll Recovery", "Demonstration of Vmca", "Stall Recovery" etc was demonstrated in the aircraft in the days when Simulators were little more than procedural training tools. The first "Simulator" I trained in, a C130A, was a fixed base model with no visual capability. Not so tough for me as a Flight Engineer, but pretty hard work for the pilots.
I have read somewhere that some items in the Qantas B707 FM had not been copied to the RAAF produced B707 FM. I cannot comment, other than to say that the only part of the RAAF B707 FM which was different to Qantas was the cover in the initial period of the aircraft's RAAF service. The publication was, in fact, the Qantas FM in a RAAF binder. Additionally, I have read elsewhere that two engines (double asymmetric) were SHUT DOWN. This, I do not believe. At no time during my association with the RAAF was an engine failure simulated by shutting down an engine. Engines were brought to idle, not closed down. The B707 rudder is the only hydraulically boosted flight control surface on the aircraft. At no time during my B707 experience was practice double asymmetric flight conducted, either in the aircraft or in the simulator. Vmca was demonstrated with one engine at idle, with and without rudder boost at FL150 over Bass Strait, likewise for Dutch Roll recovery.