CAPE CANAVERAL, Florida – The launch of the U.S. Space Force’s secretive X-37B spaceplane atop a United Launch Alliance Atlas V 501 configuration rocket remains is scheduled to liftoff at 9:14 a.m. on Sunday, May 17, 2020, from Space Launch Complex 41 at the Cape Canaveral Air Force Station in Florida.
This will be the second launch attempt after Saturday’s launch was scrubbed due to weather.
Launch Weather 80% ‘GO’
According to the latest forecast from the U.S. Air Force 45th Weather Squadron, there is an 80% chance of favorable weather for launch on Sunday.
The primary weather concerns are ground winds and cumulous clouds.
In the latest launch weather briefing, @45thspacewing meteorologists have improved the odds of favorable conditions to 80% for liftoff from Cape Canaveral this morning.
— ULA (@ulalaunch) May 17, 2020
X-37B Spaceplane Missions

This USSF-7 mission is the sixth flight (OTV-6) of the X-37B and the first launch under the newly-formed United States Space Force.
Also referred to as the U.S. Air Force’s mini space shuttle, the unmanned X-37B was originally designed for orbital missions lasting only 270 days but continues to break longevity records. OTV-5 broke the record for the most time the spaceplane has spent in space at 780 days.
X-37B Mission Durations
Mission Days
OTV-1 224
OTV-2 468
OTV-3 674
OTV-5 780
As of today, the total number of days spent on-orbit for the entire test vehicle program is 2,865 days.

In 2014, Boeing began the consolidation of its X-37B operations at Kennedy Space Center by converting the former space shuttle facility, OPF-1, to a facility that would enable the U.S. Air Force to land, recover, refurbish, and re-launch the reusable unmanned spaceplane.
Prior to consolidation, the 29-foot-long X-37B had launched from both Vandenberg Air Force Base in California and the Cape Canaveral Air Force Station in Florida – but the space plane only landed at Vandenberg Air Force Base.