- Boeing 737 Max planes have been grounded worldwide since mid-March after two fatal crashes.
- Orders for the planes ground to a halt since the planes were taken out of service by global regulators.
- Aviation regulators have not indicated when they will again allow the planes to fly.
Boeing, yet again, received no new orders for its troubled 737 Max jets last month as the worldwide grounding of its best-selling plane enters its sixth month.
The dearth of Max orders in July marked the fourth straight month without any new orders for the planes, Boeing said Tuesday.
The slowdown could give European manufacturer Airbus, which reported 389 commercial plane deliveries in the first six months of the year, the crown as the world's biggest airplane maker. Airbus' A320 planes compete with Boeing's 737s in the single-aisle segment, which comprise most aircraft orders.
The Boeing 737 Max planes have been grounded since mid-March following two fatal crashes that killed a total of 346 people. Investigators found similarities between the two crashes and implicated an anti-stall system in both deadly incidents. Boeing has prepared software fixes for the planes, but regulators have not yet said when the planes will be permitted to fly again. Both airlines and Boeing have been force to park the grounded jets, canceling thousands of flights in the process.
Boeing cut production of the 737 Max by about a fifth to 42 jetliners a month in April. The company had originally planned to ramp up production to 57 a month. The Chicago-based jet maker has a backlog of about 4,600 737 planes.
Southwest Airlines said last month that it will pull out of Newark Airport, where it offers up to 37 flights per day, so that it can reallocate its lower-than-expected capacity toward more lucrative markets, especially Hawaii.
The airline flew 34 Maxs before the grounding, and was scheduled to take delivery of an additional 41 of the planes this year. As a result of the grounding, the carrier expects its seating capacity to drop by 11% during the holiday travel season.
In Europe, Irish low-cost carrier Ryanair, says it now plans to fly just 30 Max aircraft next summer, rather than the 58 expected. CEO Michael O'Leary now says the airline is drafting plans to close some markets starting this winter.
In June, Boeing won a vote of confidence in the troubled 737 Max when British Airways' parent International Consolidated Airlines Group, said it plans to buy 200 of the jets. Boeing didn't include the orders in its monthly tally because the order isn't finalized.
— CNBC's Leslie Josephs contributed to this article.