Boeing’s dismal 2020 continued through May, when the planemaker delivered just four jets, cargo or military variants only, and saw further cancellations on the 737 MAX, which remains grounded after almost 15 months. Orders for 14 MAXes were canceled last month. In May, Boeing delivered one 767 freighter and two 777 freighters, while none of its current passenger aircraft, including the 787, were rolled out. The fourth jet was a 737-based P-8 maritime surveillance model.