Starting tomorrow morning, two launches will rock the Space Coast, with a pair of back-to-back Starlink missions atop previously-flown Falcon 9 boosters as soon as Sunday and Wednesday. Current plans call for the B1051 core—only the second Falcon 9 to fly a sixth mission—to rise from historic Pad 39A at the Kennedy Space Center (KSC) early Sunday, followed by the twice-flown B1060 from Space Launch Complex (SLC)-40 at Cape Canaveral Air Force Station just after midday Wednesday.
Sadly, hopes for United Launch Alliance (ULA) to get its snakebitten Delta IV Heavy off the ground on Friday, 23 October—this author’s birthday, of all days—came to nothing and the long-delayed mission has now been declared “indefinite on the Range” as engineers continue to work an ongoing issue with the swing-arm retraction system at the Cape’s SLC-37B.
The action is set to commence at 8:25 a.m. EDT Sunday, when the 230-foot-tall (70-meter) Falcon 9 lifts off from Pad 39A, laden with a 60-strong batch of Starlink low-orbiting internet communications satellites, in what should be the final launch from this historic site before astronauts Mike Hopkins, Victor Glover, Shannon Walker and Soichi Noguchi fly their Crew-1 mission to the International Space Station (ISS) as early as 11 November.
Providing 1.5 million pounds (680,000 kg) of first-stage muscle, B1051 will power uphill on its fourth launch of 2020 and its sixth overall. First flown in March 2019 for the Demo-1 mission of Crew Dragon, it subsequently lofted Canada’s RadarSat Constellation Mission (RCM)—the most recent Falcon 9 launch out of Vandenberg Air Force Base, Calif.—the following June, before chalking up no fewer than three Starlink flights earlier this year in January, April and most recently in early August. And B1051 looks set to become the first Falcon 9 core to fly as many as four times in a single calendar year.
The weather outlook for Sunday and the backup day on Monday appear generally favorable, with a 70-percent probability of acceptable conditions at T-0. “By Sunday morning, some low-level moisture will begin to creep back north into the area, but mid-levels are expected to remain warm and dry,” noted the 45th Weather Squadron at Patrick Air Force Base. “This, combined with the brisk northeasterly flow, will likely bring low-topped, quick onshore-moving showers from the Atlantic on Sunday morning.
While sustained wind speeds are expected to remain under the threshold, they could become briefly elevated in a shower or in gusts.” This picture is set to persist through both Sunday and Monday, with potential infringement of the Cumulus Cloud and Liftoff Winds Rules considered the principal violating factors for both launch attempts.
Three days later, at 12:26 p.m. EDT Wednesday, the veteran B1060 core may launch from SLC-40 to loft a second batch of 60 Starlinks aloft. With 120 of these small, flat-packed satellites thus launched in a matter of days, these two missions will lift the total number of “production-design” Starlinks flown since May 2019 to 893.
SpaceX founder Elon Musk anticipates a constellation of thousands of Starlinks, flying at sufficiently low altitude as to be easily “demisable” to avoid an accumulation of space debris—yet still having earned the ire of the astronomical community for their negative impact on skywatching—to be in place by the middle of the decade.
And if B1060 launches on time Wednesday, it will secure a new record of just 113 days for the shortest time it has taken a Falcon 9 core to log three missions. First flown to deliver a Block III Global Positioning System (GPS) navigation and timing satellite into Medium Earth Orbit (MEO) on 30 June, B1060 subsequently saw service on a Starlink launch last month.
Flying three times in only 113 days will eclipse by two weeks the current record-holder, B1058, which has so far launched Dragon Endeavour on 30 May, ANASIS-II on 20 July and a “Scrubtober-busting” batch of Starlinks less than two weeks ago. And as B1060 flies again only 48 days after its most recent mission, it may set an additional record for the shortest interval between two flights by a single Falcon 9 core.
If SpaceX achieves its goal of two launches by mid-week, it will also push the total number of Falcon 9 flights in 2020 to 19, making this most unfortunate of years its second-most-flown ever. The Hawthorne, Calif.-headquartered organization previously flew 18 times in 2017 and 21 times (its current personal-best) in 2018. With several other missions waiting in the wings—including Crew-1, an already-delayed GPS Block III payload, the classified NROL-108 for the National Reconnaissance Office and the Sentinel-6 Michael Freilich ocean-monitoring satellite—there stands a good chance that SpaceX may set a new personal best as early as the middle of November.
And if this week’s launches go off on time, SpaceX will have achieved those 19 missions using only eight Falcon 9 cores, with B1051 leading the pack in having flown four times. Four others, including the booster used to lift “Bob and Doug’s Excellent Adventure”, have logged three flights in 2020, whilst three other veterans flew once apiece before being lost at the end of their missions either in a pair of failed droneship landings and an intentional high-altitude breakup following January’s Crew Dragon In-Flight Abort.
ULA, on the other hand, has been waiting many months to launch its triple-barreled Delta IV Heavy from the Cape’s SLC-37B, laden with the highly secretive NROL-44 payload for the National Reconnaissance Office. The 235-foot-tall (72-meter) beast—which comprises three Common Booster Cores (CBCs), mated together—was transported out to its launch site in November 2019, with initial expectations that it would fly in June 2020.
The rationale for the longer-than-normal pad processing flow remains unclear, although fitting this mission’s pre-flight milestones in between other flights earlier in the year clearly played a role. It underwent a fully-fueled Wet Dress Rehearsal (WDR) in the second week of January, before being postponed (for still unknown reasons) from June to 26 August. The NRO then requested an additional day of delay until the 27th.
Then the technical gremlins moved in for the summer…and part of the fall, too, as circumstances would transpire. Launch on the 27th was scrubbed due to a ground pneumatics control system issue and clocks were recycled for a second try in the wee hours of 29 August. On that occasion, the countdown reached T-3 seconds, before the Terminal Countdown Sequencer Rack (TCSR) autonomously (and dramatically) commanded a “Hot Fire Abort”.
As is characteristic of the Delta IV Heavy’s staggered engine-start and ramp-up sequence, the starboard-side CBC roared to life as planned at T-7 seconds, but the proper conditions were not met for the ignition of its center and port-side counterparts at T-5 seconds. Another launch was ignominiously called off as ULA initiated an investigation, which zeroed-in on one of three pad-side regulators. All three were removed, refurbished and tested, before being reinstalled into the Delta IV Heavy.
But misfortune was far from done with the beleaguered mission. Hopes of flying on 26 September came to nought when a hydraulic issue with SLC-37B’s swing-arm system arose, forcing an additional three-day slip. Two more back-to-back scrubs were then enforced by the intractable Florida weather, with lightning warnings and a need to remove the pad crew to safety eating into their respective countdown operations. A hydraulic hose failure in the Mobile Service Tower (MST) piled yet more frustration onto the proceedings.
Finally, another attempt geared up for liftoff just before midnight on 30 September. Countdown operations proceeded smoothly, with the weather outlook classified as “Green” and the only issue of any concern was an issue pertaining to the review of data readings. Anomaly Chief Dave McFarland and his team determined that a computer-controlled redline limit would be monitored manually, to avert the potential risk of a data readings issue from tripping up the terminal countdown. A slow-to-respond pad swing-arm sensor was “masked-out” to prevent it posing any further problems.
All went smoothly, again, until the final moments before the targeted launch. At T-14 seconds, the pad-side Radial Outward Firing Igniters (ROFIs) came to life like glittering sparklers to clear unburnt hydrogen from the vicinity of the engines. But as the last seconds ticked away, something did not look quite right, for the engine-side ROFIs did not fire. At T-7 seconds, with the same ominous pall of ashen-gray smoke last seen on 29 August, the Delta IV Heavy seemingly came alive, then fell silent, as abort calls rang out across the net.
“We experienced an automated abort because a sensor reported a fault,” tweeted ULA CEO Tory Bruno in the aftermath of the scrub. “Automated Safety System operated as intended. Bird and payload are safe and unharmed. Engine ROFIs were not fired. Turbopumps were not spun up. Mission safety first.”
As frustrating as yet another scrub for the snakebitten Delta IV Heavy might be, the rocket’s safety systems performed as advertised. “Recycle is always a better trade,” tweeted Mr. Bruno, “than the risk of killing a billion-dollar payload that took many years to build.” Initial hopes of flying as soon as 15 October came to nothing and ULA ultimately announced a new target of 23 October, “to allow our team to perform additional analysis and data-monitoring of ground systems to ensure they continue to perform nominally”.
That date also came ultimately to nought yesterday, when ULA announced that NROL-44 is being delayed indefinitely on the Eastern Range. “The #NROL44 launch date is now indefinite on the range,” it noted. “With continued emphasis on mission success, our team will continue to test and evaluate the swing-arm retraction system prior to the launch of the #DeltaIVHeavy. We will confirm a launch date as soon as possible.”
This latest postponement for NROL-44, already months behind schedule, threatens to throw the remainder of ULA’s 2020 manifest into disarray. Little insight has been offered so far as to the sequence of the remaining missions and their targeted dates, although the flight of an Atlas V with the second uncrewed test of Boeing’s troubled CST-100 Starliner to the International Space Station (ISS) has already slipped into early January.
Completed so far this year have been four Atlas V missions, carrying Solar Orbiter in February, the final Advanced Extremely High Frequency (AEHF) military communications satellite in March, the latest long-duration voyage of the U.S. Space Force’s X-37B Orbital Test Vehicle (OTV) in May and NASA’s Mars-bound Perseverance rover on 30 July.
Meanwhile, out on Space Launch Complex (SLC)-6 at Vandenberg Air Force Base, Calif., another Delta IV Heavy—carrying the classified NROL-82 payload—is primed for a launch in the December timeframe. And an Atlas V, equipped with Northrop Grumman Corp.’s first trio of GEM-63 strap-on boosters, is scheduled to fly from the Cape’s SLC-41 at some point in November with the secretive NROL-101 payload.
Assuming NROL-44 does indeed fly before year’s end, it will close out 2020 with only six launches of the combined Atlas/Delta fleet. Although it will mark a slight increase over the five missions launched in 2019, it will still represent one of ULA’s least-flown years on record. Not since 2005 with its six Atlas V and Delta IV missions have so few missions be flown in a single calendar year.