(07 Jun 2016, 8:02 pm)biglugs@yahoo.com wrote Can double deckers appear on the 33?
Which 33? Not too familiar with the route in Sunderland, but there's nothing preventing double-deckers being used on the 33/33A between Newcastle and Hollywood Avenue/Fawdon. In days of Busways and TWPTE, the 33 (and the 4 which operated more or less the same route the current 33 does now) was often allocated a double-decker as seen in the examples below:
(Source: http://www.britishmodelbuses.com/Real_bu..._Large.jpg)
(Source: https://farm6.staticflickr.com/5505/9817...c963_b.jpg)