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Paddy Zulu was a real oddball and it is still a bit of mystery as to why it was ever leased. IIRC, the galleys required non-standard trolleys etc, which is probably why BA tried (vainly) to keep it on a single route (ie ORD.)
It had the lower thrust -3A engines with the notorious 'throttle-bar' for 'trouble-free' descents. The -3A engines limited MTOW to around 322 tonnes rather than the 332.9 tonnes of the regular BA -136s with -7A engines. There was also a further (obscure) reduction to MTOW which involved fuel SG and the reserve tanks. Something to do with wing-bending relief perhaps.
The arrival of the RR-236 around 1978, allowed BA to introduce LHR-SFO and LHR-LAX (direct 747) services, but there were frequent substitutions, as the -136s could usually make the West Coast with a passable load. I would be surprised if PZ was ever asked to go that far, or even to Africa. Later on, around 1980, PZ featured on the LHR-Dhahran service.
Fly GSU - 1981. We're taxying (GSU) round the outer at JFK for a night departure in PZ, when GND calls us ... "Speedbird - Your sequence is to follow the Irish 747"... Big puzzled thinks bubble - 'But we ARE the Irish 747.' Fortunately for us the pause was long enough to spot the real Aer Lingus coming out of some cul-de-sac.
LFH
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