Dayglow part 2
Astir 8
I think a following correspondent has covered this - RAF Eng Authority carries where they are RAF aircraft, in similar vein to rules re Pilot qualifications / Glider pilot qualifications vis a vis CAA and BGA. All the evidence will have been considered and a risk assessment and Eng assessment carried out by the RAF.
The proof of the pudding is in the eating thereof - no tragedies caused by dayglow causing wing rot thus far, with tens of thousands of launches and flying hours in Grob 103 and 109B and potentially many averted, - case closed ! Could be a bit of Grob risk management as a cautionary note to avoid any possible future claims - after one of their staff read too many spooky H & S manuals ! All manufacturers of any product have liability insurers that require an "exclude all causes" terms, conditions and risk avoidance bulletins.
I suppose the risk of wing heat absorption caused by colours other than white is to some extent offset by good soaring / flying at higher levels where the lower temperatures provide a natural cooling effect. Avoid the problem, get soaring ! - or use the instant lift lever in a 109B !