The largest joke in aircarft industry ever is USSR's decision to rush Tu-144 supersonic jet without very good engineering, thus making these aircarfts have very short life of only 10 years in service, and cannot even sustain 1 return flight per week of only 2000 miles (3200km) per trip (that is, only 4 flight hours per week, totalling only 2100 flight hours in 10 years, which other aircrafts would reach such level for only half year!)

Boeing's decision to produce 777-200LR (16000km range, 305 seats) & 777-300ER (13000km range, 368 seats) instead of smaller quads like A340 is the 2nd lareast joke in aircraft industry.

Antoher large joke is Lockheed's decision to produce L-1011 trijet of just 4500km range & hence very poor economy instead of longer range like DC-10 and short range twinjet like A300.

Pratt Whitney's decision to make PW6000 engines solely for A318 instead of producing smaller thrust variants of V2500 for A318 is also a very large joke, as this breaks the commonality among the A320 family members.

And Rolls Royce's decision to provide engine option only on B767-300, but not other variants of B767, not even B767-300ER, is also a large joke. This makes China Yunnan Airlines the only airline to specify B767-300 with Rolls Royce RB211-524 engine because of lack of commonality with other variants of B767.