SpaceX Falcon 9 Block 5 - NROL-87 - Launched February 2, 2022
Screenshot from SpaceX Webcast of the launch of NROL-87
Mission Rundown: SpaceX Falcon 9 B5 - NROL-87
Written: August 8, 2022
Shades. Camera. Beach. Girls. Go spy
On Wednesday, February 2 at 12:18 p.m. PST, Falcon 9 launched the NROL-87 mission from Space Launch Complex 4 East (SLC-4E) at Vandenberg Space Force Base in California. This was the first launch and landing on LZ-4 of this booster, which will be prepared for re-flight on another NRO mission later this year.
This was the first launch of the B1071-1 booster, which successfully touched down on Landing Zone 4 (LZ-4) 8 minutes after launch.
B1071-1 performed a static fire test 16:00 EST Jan. 26 after refurbishment and waiting for a west coast launch out of SLC-4. SpaceX has omitted this safety precaution many times so far. It is not required to perform a static fire test inhouse missions like Starlink, that was to save money and time before the launch.
SpaceX is the first entity ever that recovers and reflies its fairings. After being jettisoned, the two fairing halves will use cold gas thrusters to orientate themselves as they descend through the atmosphere. Once at a lower altitude, they will deploy drogue chutes and parafoils to help them glide down to a soft landing for recovery.
Falcon fairings halfs have been recovered and reused since 2019. Improved design changes and overall refurbishment procedures have decreased the effects of water landings and led to an increased recovery rate of fairings.
The fairings are a new pair Type 3.2. Both fairings survived the landing. Active fairings are equipped with four pushrods to separate the two fairings halfs.
Fairings used to have evenly spaced venting ports that have been redesigned a number of times by having first ten, then eight and now having their venting ports built as close pairs along the fairing edge. This prevents saltwater from the ocean from flooding and sinking the fairing, and makes refurbishment toward the next flight easier.
There are two models: Type 3.1 fairing with 4x2 venting ports, thermal steel tip, lowered protrusion and no acoustic tiles and the Type 3.2 with payload protecting acoustic tiles.
After lift off from Space Launch Complex 4E, SLC-4E, Falcon 9 took a southward trajectory in a slight turn - a Yaw - as it climbed through the atmosphere. The first stage’s nine Merlin-1D# engines cut off around the T+2 minutes 30 seconds mark, with stage separation and a 1st stage 150° flip maneuver following within seconds after MECO.
The second stage continued NROL-87’s journey to orbit while the first stage performed a 42 second long boost back burn to put it on a course back to the launch site.
Unlike most recent Falcon 9 launches from Florida, the NROL-87 flight’s booster did not need a drone ship sent out to the Pacific to recover it. Instead it flew a return to launch site (RTLS) profile, with the booster touching down on the concrete pad at Landing Zone 4 (LZ-4) back at the Cape.
After the boostback burn was completed, B1071-1 positioned itself for atmospheric entry before conducting an entry burn to protect the stage from excess heating — fighting fire with fire — by slowing the stage down. The final landing burn began shortly before touchdown, slowing the booster to a soft landing at LZ-4.
SLC-4 is Falcon 9’s launch and landing site at VSFB. The entire complex is composed of several launch sites but two of them - SLC-4E (East) and SLC-4W (West) - are now leased and used by SpaceX. SLC-4E is used as Falcon 9’s launch site. Falcon 9 launched in September 2013 on the CSA’s CASSIOPE mission. Since then, it has been used 18 more times, with NROL-87 the 20th SpaceX launch from the pad.
SLC-4W west was unused for Falcon 9 launches. It was instead converted from a Titan launch site to a landing pad in the mid to late 2010s. Now named LZ-4, it was first used in a first-stage, West Coast Return to Launch Site (RTLS) landing in October 2018 on the SAOCOM-1A mission. Since then, it has been used three times.
The Secret Payload
The National Reconnaissance Office is a government agency that is a part of the US Department of Defense. Since its formation in 1961, the NRO has been responsible for the US’s reconnaissance satellites. Every year, the NRO launches new payloads into space, with more missions set to launch this year following NROL-87.
This is SpaceX's third overall mission for the NRO. In 2017 and 2020, SpaceX launched the NROL-76 and NROL-108 missions, respectively. Both were likely technology demonstration missions and were placed in LEO.
As for NROL-87, not much is known about the payload. The contract called for Falcon 9 to deliver the payload to a 512.7 km circular Sun-Synchronous orbit (SSO) with a 97.4-degree inclination. This type of orbit points to the payload being a next-generation electro-optical reconnaissance satellite.
The RTLS landing at LZ-4 also points to the payload being lighter and smaller in size.
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