Why Falcon Heavy Just Launched Without Any Landing Gear
Last night after lightning and a few other delays, the sixth Falcon Heavy lifted off, however, there were a few differences from a typical launch. For one, the reusable rocket had no landing legs installed, and instead of three recovered boosters, all were expended during the mission. Not to mention, the upper stage featured a gray band at the top crucial to the success of the launch.
In reality, the massive primary payload and its distant orbit forced SpaceX to utilize every bit of power and launch with a fully expendable Falcon Heavy. As for the gray band, this was needed due to the mission’s long coast phase between subsequent burns. Both of which allowed Falcon Heavy to successfully deliver its primary and secondary payloads to their respective orbits.
While it’s not ideal to expend three boosters that could have been resued, mission requirements determine what ends up happening to the rocket. Here I will go more in-depth into the decision to expend the entire rocket, the importance of the gray band, what to expect in the coming weeks, and more.
No Landing Gear
For a few days now Falcon Heavy was trying to launch but weather and a few other factors kept pushing the mission back one day to the next attempt. Eventually, yesterday on Sunday, April 30 at 8:26 p.m. ET, Falcon Heavy launched the ViaSat-3 Americas mission, delivering the ViaSat-3 Americas, Astranis’s first MicroGEO satellite, and Gravity Space’s GS-1 satellite to a geostationary orbit from Launch Complex 39A (LC-39A) at Kennedy Space Center in Florida.
Originally, Falcon Heavy was slated to launch the Viasat-2 satellite, but due to delays an Ariane 5 launch vehicle was used instead. Viasat maintained the launch option and delivered its next Ka-band satellite aboard the Falcon Heavy – this one intended to provide service to the Americas region.
The specific Falcon Heavy for this mission expended all three of its boosters due to the need for all available performance. This had to do with the mission profile to insert the ViaSat-3 Americas satellite directly into geostationary orbit. A geostationary orbit, also referred to as a geosynchronous equatorial orbit (GEO), is a circular geosynchronous orbit 35,786 km (22,236 mi) in altitude above Earth’s equator. In comparison to low Earth orbit for example, GEO is much more taxing and requires an extremely powerful launch vehicle when the weight of the payload is high. With a Falcon Heavy and even a Falcon 9, the boosters normally require residual fuel for the deceleration and turnaround maneuver and the controlled descent and landing. When in an expendable configuration such as yesterday’s launch, every bit of propellant and performance is utilized to accelerate and help place the payloads on the correct trajectory.
For this reason, there was no need for SpaceX to have landing legs or even grid fins on a single one of the three boosters. As far as what happened to them, the boosters were expended by falling into the Atlantic Ocean after separation. Not long after the core stage was expended in the same way. Images of the rocket prior to launch showed off two of the boosters that obviously were reused from prior missions based on the state of paint and char. Specifically, one of the side boosters on this mission previously supported Arabsat-6A, STP-2, COSMO-SkyMed Second Generation FM2, KPLO, and three Starlink missions, and the second previously supported launch of Arabsat-6A and STP-2. Falcon 9 and Heavy boosters do have somewhat of a lifespan and it’s better to expend boosters that have already flown a decent amount of missions than brand new hardware or a booster with just one launch on its record.
Interestingly, even the Falcon Heavy launch before yesterday’s mission featured an expendable first stage. In this case, just a few months ago in January, a Falcon Heavy lifted off a part of the USSF-67 mission with reusable side boosters but an expendable center core. Since this was a Space Force mission we know very little about the payload and destination, however, it’s clear that in that specific case, a bit more performance was needed from Falcon Heavy.
Falcon Heavy payload performance to geosynchronous transfer orbit (GTO) is reduced by the reusable technology, but at a much lower price. When recovering all three booster cores, GTO payload is 8 t (18,000 lb). If only the two outside cores are recovered while the center core is expended, GTO payload would be approximately 16 t (35,000 lb). This helps put in perspective the payload and performance increases when the boosters are expended.
Gray Band & Future
Not only did the mission feature no landing legs or grid fins, but it also had a gray band on part of the upper stage. This addition is not for looks but instead plays a very important role, something we are seeing more of with both Falcon Heavy and Falcon 9. This mission featured a long coast phase between subsequent burns, and in order to allow more heat from sunlight to be absorbed to warm the RP-1 kerosene tank during the longer coasting period, the gray band was added around the tank. When it gets too cold, kerosene – which freezes at a much higher temperature than Falcon’s liquid oxygen oxidizer – becomes viscous and slush-like before it freezes solid. If ingested, slushy fuel would likely prevent ignition or destroy the upper stage’s Merlin engine.
It was reported that following a series of MVac engine burns and long periods of coasting, the upper stage of Falcon Heavy deployed the satellite into a near-geosynchronous orbit at approximately T+4:32:27. SpaceX soon confirmed that the upper stage went on to successfully deploy the additional payloads, G-Space 1 and Arcturus. Overall it marked another successful Falcon Heavy launch, something we have seen an increase in very recently. After going years without a launch, the heavy-lift rocket is back and is busier than ever.
Between now and the end of 2023, there are at least another three missions scheduled including USSF-52, Jupiter-3, and Psyche. Then in 2024, 5 missions are scheduled with one of the most notable being Europa Clipper. Europa Clipper will conduct a detailed survey of Europa and use a sophisticated suite of science instruments to investigate whether the icy moon has conditions suitable for life. Key mission objectives are to produce high-resolution images of Europa’s surface, determine its composition, look for signs of recent or ongoing geological activity, measure the thickness of the moon’s icy shell, search for subsurface lakes, and determine the depth and salinity of Europa’s ocean.
Not only this, but there’s also an upcoming Falcon Heavy launch responsible for the heaviest commercial satellite ever sent into space. In early 2022 at a press meeting during the Satellite conference, Hughes President and CEO confirmed that SpaceX would be launching its 500 Gbps Jupiter 3 satellite. This is the newest Ultra-High-Density Satellite in the Hughes’ satellite network, expected to be the world’s largest broadband satellite network to communities, businesses, and aeronautics. Jupiter 3 weighs around 9,200 kilograms or 20,280 pounds. This makes it the heaviest commercial satellite in history. In terms of capabilities, Falcon Heavy features a payload capacity to low Earth orbit of 63,800 kg / 140,660 lb. However, as partially mentioned prior, this satellite is going into geostationary orbit which takes much more propellant to reach. At this specific orbit, Falcon Heavy’s payload capacity drops to 26,700 kg / 58,860 lb, still well within range for this specific satellite.
Over the last few years, this satellite has faced quite a few changes in plans regarding the schedule and launch provider. The company had previously signed a launch contract in late-2020 but at that time refused to declare with whom. They also announced a small delay to the planned launch from the second half of 2022 to the fourth quarter of 2022. In May of last year, they announced that it would not launch before the first quarter of 2023. “This delay is due in part to relocation of critical resources at Maxar to a higher priority government-related spacecraft project,” said the president of Hughes Networks Systems, the EchoStar subsidiary that operates the Jupiter network. Now in May, the launch is scheduled to happen in only a few months in August.
This exciting future for the rocket brings up the question of why did it take over 3 years for it to launch again. In reality, there are a variety of reasons why but one of the most impactful has to do with the success of the Falcon 9. While in development, SpaceX was not quite sure how powerful the rocket would turn out and its capabilities once finished. In reality, the Falcon 9 turned out to be a lot better than expected which had an effect on the Falcon Heavy. Specifically, due to improvements to the performance of Falcon 9, some of the heavier satellites flown to GTO, such as Intelsat 35e and Inmarsat-5 F4, ended up being launched on a Falcon 9. Another reason had to do with the demand or lack thereof for a rocket capable of lifting almost 64,000 kilograms to low earth orbit and almost 27,000 to GEO. Thankfully, as time has gone on, the rocket’s future launch schedule suggests a slight shift in demand and use of the Falcon Heavy.
Conclusion
Falcon Heavy just launched again but this time without a single grid fin or landing gear. This was because of the payload requirements and destination which forced Falcon Heavy to use every bit of power and performance available. We will have to wait and see how it progresses and the impact it has on the space industry.