SpaceX Falcon 9 Block 4 - Iridium-5 NEXT - Launching March 30, 2018
Screenshot from and of SpaceX Falcon 9 B4 - Iridium-5 NEXT
Mission Rundown: SpaceX B4 - Iridium-5 NEXT
Written: January 15, 2021
It’s raining hard with rocket parts
SpaceX will launch a flight-proven Falcon 9 Full Thrust booster with a Block 5 second stage to put 10 Iridium NEXT communication satellites into a low earth polar orbit. These satellites are all deployed into plane orbit 1.
SpaceX is launching the Iridium-5 on Friday, March 30 from Space Launch Complex 4E (SLC-4E) at Vandenberg Air Force Base, California. The instantaneous launch opportunity is at 07:13:51 p.m. PDT, or 14:13:51 UTC. The deployment of the 10 Iridium® NEXT satellites will begin about an hour after launch.
Falcon 9’s first stage B1041-2 launching the Iridium-5 mission previously supported the Iridium-3 mission from Space Launch Complex 4 East (SLC-4E) at Vandenberg Air Force Station in October 2017. SpaceX will not attempt to recover Falcon 9’s first stage after this launch. But they will test land it on the surface.
Iridium-5 NEXT
Iridium NEXT flight 5 will send all of its satellites into plane 1 of the Iridium constellation, where they will relieve 10 old Iridium Block 1 satellites one by one as they clear the ground testing checkouts and orbit maneuvers necessary to do so. With this launch there are now 50 second-generation Iridium-NEXT satellites in orbit.
Apparently the Iridium launch plane precesses at a rate of about 5.5 min/day compared to the launch site SLC-4E at Vandenberg Air Force Base, California. So a different launch date will give a different launch time, since they both need to be aligned. In a month the launch time shifts an hour.
Iridium’s first-generation satellites were built around Lockheed Martin’s LM-700A bus, with a design life of eight years. Between 2002 and early 2017, no further satellites were launched to replenish the constellation. This all changed in January 2017 when SpaceX deployed the first ten second-generation Iridium-NEXT satellites.
The NEXT generation satellites are built around Thales’ Extended Lifetime Bus – ELiTeBus-1000 – platform. Each one has a mass of 860 kilograms (1,900 lb) and is expected to operate for at least 20 years. The satellites carry L-band transponders for mobile communications and Ka-band transponders to provide crosslinks between satellites and downlink to ground stations.
The Iridium constellation’s crosslink capability allows each satellite to relay data directly to the four other satellites: those immediately ahead of and behind it in the same orbital plane, and those operating parallel to it in the two adjacent planes.
This allows calls to be routed around the network without needing to pass through ground stations, reducing latency and also cost – as fewer ground stations are required. The sixty-six operational Iridium satellites are arranged in six planes of eleven spacecraft, orbiting at an altitude of about 780 kilometers (485 miles, 421 nautical miles) and a near-polar inclination of 86.4 degrees.
Iridium Communications, the successor company to Iridium SSC, has ordered a total of 81 new satellites being built by Thales Alenia Space and Orbital ATK: 66 operational units in six planes, nine on-orbit spares flying below the operational satellites, and six on ground spares that have yet to be launched into orbit.
In August 2008, Iridium selected two companies — Lockheed Martin and Thales Alenia Space — to participate in the final phase of the procurement of the next-generation satellite constellation. The constellation provides L band data speeds of up to 128 kbit/s to mobile terminals, up to 1.5 Mbit/s to Iridium Pilot marine terminals, and high-speed Ka-band service of up to 8 Mbit/s to fixed/transportable terminals.
The NEXT satellites incorporate a secondary payload for Aireon, a space-qualified ADS-B data receiver for use by air traffic control and, via FlightAware, by airlines. A tertiary payload on 58 satellites is a marine AIS ship-tracker receiver for Canadian company ExactEarth. Iridium NEXT is also capable of carrying internet connectivity.
NOAA Whats up???
At T+ 9:00 minutes, just two seconds before the rocket's second-stage engine cut off from firing, the video from SpaceX ended. The launch commentator, SpaceX engineer Michael Hammersley, explained earlier in the broadcast that due to some restrictions from the National Oceanic and Atmospheric Administration, SpaceX will be intentionally ending live video coverage of the 2nd stage just prior to engine shutdown.
Asked about this on Friday morning, a NOAA spokesman was not aware of the situation. "I can only think it's an error," Chris Vaccaro told Ars. "I would double check with them (SpaceX)." NOAA has promised more information will be forthcoming. (4:45pm ET Update: NOAA released this statement).
We did a double check with SpaceX. It was definitely an issue with NOAA, the rocket company said. Apparently NOAA recently asserted that cameras on the second stage of the Falcon 9 rocket, which SpaceX uses for engineering purposes, qualify as a remote sensing system, which are subject to NOAA's regulation. A provisional license obtained by SpaceX for Friday's launch of the Iridium-5 mission required it to end views once the second stage reached orbit. Source: Eric Berger. Ars Technica.
The fairing recovery
One of the fairings is equipped with a parachute and cold N2 gas RCS thrusters, and Mr Steven is deployed on a fairing recovery attempt in the Pacific Ocean. Unfortunately the fairing landed hard with a twisted parachute and was broken on a wave crest.
A fairing measuring 34 by 17 feet is the size of a lifeboat. That is evident when they float on the Pacific Ocean waiting to be lifted aboard Mr Steven and the other recovery vessels in SpaceX's tiny but growing fleet. - This fairing looks too clean. - Drop test fairing?
This fairing? landed hard, cracked the bottom and are taking in seawater - March 30, 2018
Another thought comes to mind, could SpaceX deploy a giant inflatable landing zone drawn by two or more boats below the descending fairing. They can cover entire football fields to protect them from water, why not this? Or an old oil tanker covered in cardboard boxes like a stuntman's landing zone. Or the James Bond method of picking the fairing out of the sky with a cargo plane. Like in Thunderball 1965.
A fairing half consists of a carbon/glass fiber shell with a 4 inch honeycomb aluminum spacer and black mats with sound suppressing material, on the edge there are 12 hinges that fits into 12 slots on the other fairing half, who each has a retractable bolt used to unhinge the fairing halves. 4 pusher pistons top and bottom press the two halves apart during fairing separation.
When ascending a flight computer keep track of key instruments, reading their values and keep the fairing oriented belly down using RCS nitrogen cold gas thrusters for and aft. At a pre-programmed altitude a drogue chute mortar is activated, and later a steerable large parachute is deployed so the fairing is hanging from 8 parachute cords and Mr Steven is trying to get under the fairing for an aircatch in the big net.
The first test fairing landed safely according to Elon Musk tweet of 22 february 2018
Screenshot of Mr Steven on fairing recovery duty full speed ahead
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