With Block 5, SpaceX to increase launch cadence and lower prices

by Michael Baylor

On May 11th, SpaceX successfully launched a Block 5 Falcon 9 – the final major version of the launch vehicle. Most notably, Block 5 features a fully reusable first stage – capable of being launched twice in a single day. Such capabilities will help SpaceX tackle its busy launch manifest at an unprecedented low cost.

High launch rate:

In 2017, SpaceX launched 18 Falcon 9 rockets – a massive increase from the eight launched in 2016. This year, SpaceX is expected to launch approximately 30 times. The majority of the launches will utilize the Falcon 9, with a couple utilizing Falcon Heavy. Thus far, SpaceX has executed nine launches in 2018 – eight on Falcon 9 and one on Falcon Heavy.

According to a tweet by SpaceX CEO Elon Musk, the company plans to perform approximately 300 missions using Block 5 over the next five years. To do so, SpaceX needs to reach a launch rate of 60 flights a year.


Block 5 first stages are designed to fly up to ten times with little to no refurbishment. In fact, with a scheduled maintenance every ten flights, it will be possible to launch a Block 5 first stage up to 100 times.

However, Musk announced in a conference call ahead of Block 5’s debut last week, that SpaceX plans to build a fleet of approximately 30-50 Block 5 first stages.  Therefore, it is unlikely that a booster will need to be flown anywhere close to 100 times.

Musk stated that the exact number of cores required “depends on what number of customers insist on launching a new rocket.”

However, he is confident that the customer’s sentiment will change over time. Musk explained, “would you rather fly on an aircraft that has never had a test flight before, or would you rather fly on an aircraft that has flown many times successfully?”

To date, SpaceX has not reflown the same core more than once, as the Block 3 and Block 4 variants of the Falcon 9 required more extensive refurbishment between flights. Additionally, with Falcon 9 receiving multiple Block upgrades over the past few years, existing cores have quickly become outdated.

Therefore, SpaceX has been expending Block 4 cores during their second flights.

Block 5 is the final major version, so it will stay relevant as long as SpaceX continues to operate the Falcon 9 and Falcon Heavy launch vehicles.

A drone captures the first launch of a Block 5 Falcon 9. Credit: SpaceX

With Block 5, SpaceX will finally start reusing cores more than once. In fact, according to Musk, first stages will be reflown three or four times by the end of this year. Furthermore, ten flights of a single booster will occur in 2019.

Getting to the point of rapid reusability has not been easy. Musk added, “for those that know rockets, this is an incredibly hard thing. It has taken us since 2002. 16 years of extreme effort and many, many iterations. Thousands of small but important development changes to get to where we think this is possible. Crazy hard.”

Next year will also see another milestone in SpaceX’s quest for full and rapid reusability. Musk announced that they “intend to demonstrate two orbital launches of the same Block 5 vehicle within 24 hours.” This feat is made possible by the fact that no significant work is needed to refurbish the first stage between flights.

Currently, it takes 3-5 days to transport a booster which is recovered on a droneship back to a hangar near the launch pad. However, on some missions, SpaceX can return to a landing zone closer to the launch site. Doing so can reduce transport times to less than a day.

On May 15th, the Block 5 from the Bangabandhu mission – designated B1046 – arrived in Port Canaveral. The arrival allowed for the first look at Block 5’s post-landing operations.

A new lifting cap is lowered onto B1046’s interstage. Credit: Marek Cyzio for NSF L2

One of the most notable changes was a new lifting cap which allows a crane to transport the booster. The cap appeared to be an upgrade from the one used for previous cores. Notable changes included several new cameras and sensors.

Additionally, Musk had also mentioned that Block 5’s landing legs have “an internal latch which can be opened and closed repeatedly with ease. Essentially, deploying the landing gear and stowing the landing gear is now a very easy thing to do, whereas previously it required several hours to restow the landing gear.”

Therefore, it was expected that SpaceX would not remove the landing legs on B1046. Surprisingly, they did remove the landing legs.

The new Block 5 landing legs support B1046 on the droneship. Credit: Marek Cyzio for NSF L2

One reason is that SpaceX will have to wait for the next Block 5 launch to demonstrate how quickly a booster can turn around for another flight. According to Musk, they “need to take this rocket apart to confirm that it does not need to be taken apart.”

Consequently, “this [B1046] won’t refly for a couple months.”

Low cost:

Due to the Block 5’s reusability, SpaceX has lowered the standard price of a Falcon 9 launch from $62 million to about $50 million. This move further strengthens SpaceX’s competitiveness in the commercial launch market.

In fact, even at the $62 million price point, SpaceX was already starting to win contracts that would have previously gone to competitors such as Arianespace.

As for Falcon Heavy, SpaceX is yet to release the updated price for the Block 5 version. However, Falcon Heavy – which was priced at $90 million – uses three first stage cores instead of one. Everything else about the rocket is the same as Falcon 9. Therefore, in all likelihood, the price of Falcon Heavy will drop by a larger margin than it did for Falcon 9.

Half of a payload fairing returns to Earth via parafoil. Credit: Elon Musk

In the future, SpaceX’s launch prices could become even cheaper. The company is currently working on recovering the payload fairing which is worth approximately $6 million.

That leaves only the second stage without a recovery plan.

While the Block 5 second stages are not currently outfitted with recovery hardware, it is something that is under consideration.

Musk said last week, “in the upcoming flights [SpaceX will] gather data about the reentry experience of the upper stage. Previously, we had not put a lot of effort into gathering data from the upper stage after it does its disposal burn. We will monitoring at what altitude and speed the stage breaks up…”

Collecting this data is not easy. Musk explained that “it’s tricky because it comes in like a meteor. It’s sort of like a ball of plasma. You can only broadcast diagonally backwards, so we will be looking to communicate, probably [with] the Iridium constellation, and try to transmit basic data about temperature, basic health of the stage, velocity, and altitude.”

Hardware changes may start as soon as this year. Musk added, “over the course of this year, we will be adding more and more thermal protection to the upper stage, and trying to see what’s the least amount of mass necessary to return the upper stage in a condition that is reusable. I am actually quite confident that we will be able to achieve full reusability of the upper stage. In fact, I am certain we can achieve full reusability. The question is what the mass penalty is.”

Concerning how much each portion of the rocket is worth, Musk said that the first stage “represents close to 60% of the cost, the upper stage is about 20%, the fairing is about 10%, and about 10% is associated with the launch itself.”

With full reusability combined with a bit of work to optimize the cost of launch operations, Musk is confident that SpaceX can get “the marginal cost of a Falcon 9 launch down under $5-6 million.”

While achieving lower launch costs may not be critical for SpaceX’s competitiveness in the commercial launch market – as they already have a substantial lead – it could prove very useful for their planned Starlink constellation.

The system is designed to improve global internet access by utilizing thousands of satellites in Low Earth orbit.

Two Starlink demonstrations satellites which launched as a rideshare on the PAZ mission. Credit: SpaceX

SpaceX President Gwynne Shotwell stated in a TED Talk last month that she expects the constellation to cost at least $10 billion. Therefore, reducing launch costs will be vital.

The FCC has authorized an initial constellation of 4,425 satellites. Furthermore, the authorization requires at least half of the constellation to be deployed by March 29th, 2024. Therefore, SpaceX will have to launch over 2,200 satellites within the next six years.

This requirement may indicate that a sizable chunk of the 300 Block 5 missions will be dedicated to Starlink. However, with SpaceX preferring to remain secretive about the program, we will have to wait and see.

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