The airshow, the second biggest in the world, runs to Sunday. That would be worth $6.3 trillion at list prices versus last year's $6.1 trillion forecast.
The agreement was announced at the Farnborough International Airshow now being held in the United Kingdom, a leading industry event that is expected to provide the platform for a number of similar announcements over the course of the coming week.
European jetmaker Airbus and USA rival Boeing have been enjoying an nearly decade-long boom thanks to rising emerging markets growth and a need among Western airlines to upgrade their fleets, and order books are bulging.
Russian airline Volga Dnepr committed to buying Boeing freighters worth $11.8 billion at list prices, while US leasing company Air Lease Corp committed to buying as many as 78 Boeing aircraft worth $9.6 billion.
But analysts cautioned many deals firmed up provisional ones, disclosed previously unidentified buyers, or changed existing orders, making it hard to gauge the level of demand.
Britain is also expected to make a major announcement on future combat air strategy, though Europe's fragmented fighter industry is seen as far from ready to unify around one project.
Boeing, which calls itself America's biggest exporter, delivered more than one out of every four jetliners it made past year to customers in China, one of the world's fast-growing aircraft markets. The stock has been moving broadly higher in the past week or so, despite uncertainty surrounding the ongoing US-China trade disagreements.
According to Boeing, global air freight demand grew nearly 10% during 2017. "A nation where, post Brexit, we are considered the best place in the world for the aerospace industry to base its business", said Mrs May.
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Petersburg Economic Forum was visited by 500 businessmen". "Yes, I did", Putin said, when asked if he wanted Trump to win. Intelligence officials publicly broke from the president's comments about Russian meddling in the 2016 campaign.
The company's sales forecast for the next two decades predicts a 5% rise to 31,360 in demand for single-aisle aircraft, such as the Boeing 737 and Airbus A320 families, which are popular with low-priced airlines.
Boeing's Tinseth said Airbus sought to show it was winning a sizable share of the aircraft market. "By every measure, in every way, our wide-bodies are winning".
Boeing's upbeat sales forecast underlined the importance of China to the aircraft industry.
Also, he said, demand for cargo aircraft would also increase on the back of e-commerce, with Chinese traders and consumers accounting for the biggest single rise.
Goshawk Aviation Limited announced an order for 20 737 MAX airplanes and the order marks the first time the aircraft lessor has purchased jets directly from Boeing.
The order contest is expected to stretch for the days of the July 16-22 air show, although analysts will be watching closely to see how numerous deals are new, and how many involve adjusting earlier business or switching models - something not always easy to spot at first.
Boeing trimmed its forecast for the regional jet fleet to 2,320 deliveries.