Savoia
I also had a look at 'Atticus' (G-ATUS) shield in the photo posted in this thread and it looks like some sort of animal in the heraldic rampant position in red & gold on a black background.
I thought it might be the Quinton Hazell logo but that is red dragon on a white background (see link
Quinton Hazell logo, Vector Logo of Quinton Hazell brand free download (eps, ai, png, cdr) formats).
Could it be a Ferranti family crest? or even Sir Quinton's own?
Perhaps your contacts could confirm?
Re the Ferranti info, glad to be of help. I look forward to your Ferranti Helicopters tribute site later this year.