Not got a lot for you, Yak 11 Fan.
As Pimpernel says the man to see is Bob, Robert J Collis as he is the man who has assisted Neil Storey with the book Norfolk in the Second world war from which I am getting the information from. It is a great book full of information about the people of Norfolk ,what they did and went through etc. Including who got bombed and when.

In Fact the same day as the plane we are talking about.
Bombs fell on Banham 5 incendries IB, Bircham 4 High explosive. HE, Carlton Rode 2 IB, Catton 7 HE, Cranwich 2 HE, Horning 2 HE, Hoveton 2 HE, Matlaske 10 HE, Pulham ST Mary 17 HE, St Faiths 2 HE, Snetterton 4 IB, Sprowston 2 IB, Thorpe 12 HE, Watton 13 HE, West Caister 3 IB and Wickmere 9 HE.

21st Aug 1940 Do. 17Z-3 From 2/KG2 was shot down by blue section of no.242 sqd (Flt .Lt G Powell-sheddon, sub –Lieut R E Gardner and Pilot Officer J B Latta) during a sortie over Norfol. Attempted a forced landing but overshot and ploughed into a wood and exploded at Conifer hill Starston at 11.52 pm. approx.
Crew: 1 Killed, 2 wounded.
Lieut H. Ermecke was killed, Uffz. G-D Wulf, H Herman and war correspondent Sonderfuhrer Lt Kurst Rashe (of Lw. Kr. Ber. Komp. Mot.3) bailed out and were captured severely wounded. Aircraft U5+FK was a write off. This was the only German aircraft shot down on land in Norfolk during the battle of Britain.