Following a successful engine test firing of the Falcon 9 first stage late Thursday afternoon (Aug. 30), SpaceX is targeting a post Labor Day launch of the U.S. Air Force’s unmanned X-37B reusable mini-shuttle – a technology testing spaceplane.
The brief but critical hold down engine test took place at 4:30 p.m. EDT (2030 GMT) Aug. 31 at Launch Complex 39A on NASA’s Kennedy Space Center – as witnessed live by myself and a few spectators from nearby Playalinda Beach Causeway. See my photos herein.
Both SpaceX and the Air Force announced the target launch date after completion of the Aug. 31 engine test.
“Static fire test complete,” SpaceX confirmed via Twitter soon after completion of the test, “—targeting Falcon 9 launch of OTV-5 from Pad 39A at @NASAKennedy on Thursday, September 7.”
The routinely done static fire test and involves conducting a full launch dress rehearsal and countdown culminating with igniting all nine Merlin 1D first stage engines during a hold down test at the pad.
The Merlin’s generated a combined 1.7 million pounds of thrust and a huge exhaust plume billowing into the air from the north side flame trench during the test, which lasted several seconds.
The plume soon swirled overhead and dissipated about 10 minutes later. Ignition was accompanied by a loud roar we heard screaming out from the pad in all directions.
The rocket will be lowered rolled back horizontally on the transporter erector into the SpaceX processing hangar and the spaceplane housed inside the payload fairing will be integrated on top. The full stack will then be rolled back out and erected at pad 39A.
The exact launch time had been a closely guarded secret – until this evening.
The X-37B launch is apparently lunchtime Thursday, September 7 at 12 PM – 12:01 PM, according to a Facebook post by the U.S. Air Force Space Command and the 45th Space Wing at Patrick Air Force Base, Fla., posted Friday evening.
“The Air Force Rapid Capabilities Office is undergoing final launch preparations for the fifth mission of the X-37B Orbital Test Vehicle [OTV],” the Secretary of the Air Force Public Affairs announced. “The OTV is scheduled to launch on Sept. 7, 2017, onboard a SpaceX Falcon 9 launch vehicle.
The X-37B will be launched for the fifth time on the OTV-5 mission atop a SpaceX Falcon 9 on Sept. 7 from Launch Complex 39A on the Kennedy Space Center.
The Boeing-built X-37B is processed for flight at KSC using refurbished NASA space shuttle processing facilities now dedicated to the reusable mini-shuttle, also known as the Orbital Test Vehicle (OTV). It launches vertically like a satellite but lands horizontally like an airplane and functions as a reliable and reusable space test platform for the U.S. Air Force.
But in another first, the OTV-5 mission marks the first launch of an X-37B spaceplane by SpaceX.
All four prior OTV missions launched on the United Launch Alliance Atlas V.
“The many firsts on this mission make the upcoming OTV launch a milestone for the program,” said Randy Walden, the director of the Air Force Rapid Capabilities Office.
“It is our goal to continue advancing the X-37B OTV so it can more fully support the growing space community.”
The OTV-4 mission launched on the ULA Atlas V on May 20, 2015 from Space Launch Complex-41, on Cape Canaveral Air Force Station.
After spending a record setting 718 days in orbit, the X-37B program completed its fourth mission by landing back at KSC’s Shuttle Landing Facility on May 7, 2017. Overall OTV’s have spent a total of 2,085 days in orbit.
Playalinda Beach is located just 4 miles north of pad 39A and offers an excellent launch viewing location for the OTV-5 mission – if officials allow it to be open to the public.
The engine test comes at the end of a very busy August with a trio of Florida Space Coast launches plus a Total Solar ‘Eclipse Across America’ sandwiched in between.
Also noteworthy is that OTV-5 will be launched into a higher inclination orbit compared to the prior four, serve as a technology testbed for research payloads and will also deploy several cubesats.
“The fifth OTV mission continues to advance the X-37B’s performance and flexibility as a space technology demonstrator and host platform for experimental payloads,” the USAF said in a statement.
“This mission carries small satellite ride shares and will demonstrate greater opportunities for rapid space access and on-orbit testing of emerging space technologies. Building upon the fourth mission and previous collaboration with experiment partners, this mission will host the Air Force Research Laboratory Advanced Structurally Embedded Thermal Spreader payload to test experimental electronics and oscillating heat pipe technologies in the long duration space environment.”
SpaceX will also attempt another land landing of the 156-foot-tall Falcon 9 first stage back at Landing Zone-1 (LZ-1) at the Cape.
“The fifth OTV mission will also be launched into, and landed from, a higher inclination orbit than prior missions to further expand the X-37B’s orbital envelope.”
The 11,000 pound (4990 kg) state-of -the art reusable OTV space plane is about a quarter the size of a NASA space shuttle. The vehicle measures 29 ft 3 in (8.9 m) in length with a wingspan of 14 ft 11 in (4.5 m).
Watch for Ken’s continuing onsite X-37B OTV-5 and NASA mission reports direct from the Kennedy Space Center and Cape Canaveral Air Force Station, Florida.
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