A now deleted post included the statement "I've never heard of Perf A".
We have a terminology problem. UK national regs, specifically BCARs (British Civil Airworthiness Requirements) were the regs under which I first encountered public transport performance requirements, in the late 1970s. These were replaced by JAR 25 in the 1990s.
BCARs had several performance Groups, the highest of which, Group A, applied to aircraft with more than 19(?) seats or max gross weight of 5700kg. It required the aircraft to be able to tolerate the loss of the power of one engine at any time from brake release to the end of the landing roll. Other Groups applied to smaller aircraft and were less demanding.
Thus Group A was addressing broadly the same types as FAR 25, with broadly the same performance requirements.
The now deleted post included a link to a Flight Safety Foundation document that addressed some of the background I was looking for, such as the US codes under CAR4b that covered propliners and predated JAR25. No sign yet of the early US or UK jet certification standards.
I'm aware that AvP970 was the UK military design standard source. Its successor, DefStan970, is available online, but 1950ish AvP970 so far eludes me.
So, some progress; thank you.
Last edited by kenparry; 24th Feb 2018 at 09:04.
Reason: typo