According to the operational doctrine developed by the RAF, in the circumstance of deploying a large-scale nuclear strike, each Victor would have operated entirely independently; the crews would conduct their mission without external guidance and be reliant upon the effectiveness of their individual tactics to reach and successfully attack their assigned target; thus great emphasis was placed on continuous crew training during peacetime. Developing a sense of a crew unity was considered highly important; Victor crews would typically serve together for at least five years, and a similar approach was adopted with ground personnel. In order to maximise the operational lifespan of each aircraft, Victor crews typically flew a single five-hour training mission per week. Each crew member was required to qualify for servicing certificates to independently undertake inspection, refuelling and turnaround operations.