SpaceX Falcon 9
The Block 5 Falcon 9 can be used 10 times before refurbishment and has a service life of about 100 launchesSpaceX

Last weekend saw the maiden launch of the final iteration of the Falcon 9, called the Block 5. The space company had said earlier that this will be the last upgrade made to the Falcon 9. It is also likely to be used as the booster in the company's upcoming Falcon Heavy launches, and the rocket that will soon take humans to the SpaceX Dragon for the first time.

SpaceX seems to have perfected the rocket to such extent that Musk has even gone ahead and called the Block 5 Falcon 9 "the most reliable rocket ever built," as reported by

"That is the design intent," he said. "I hope fate doesn't punish me for these words, but that is unequivocally the intent. And I think our most conservative customers would agree with that." The Block 5 Falcon 9 reportedly has a lifespan of 100 launches with refurbishments required only once every 10 launches. 

One of the biggest upgrades made to Falcon 9 was the redesign of a pressure vessel. The 2016 explosion was attributed to this component and has now been replaced in spite of not having any failures since.

Called the composite overwrapped pressure vessels (COPV), they are used to store helium to keep the propellant tanks pressurized in the rocket's stage 2, notes the report.

The Block 5 launch, which saw a slight hiccup on the day of launch, was successfully launched 24 hours later without a glitch. Just 11 minutes later, the first stage separated from the payload and made a smooth landing on Of Course I Still Love You, the autonomous drone ship/landing pad stationed about 630 km off the coast of Florida in the Atlantic.

"This is by far the most advanced pressure vessel ever developed by humanity," Musk said. "It's nuts. I've personally gone over the design; I can't count how many times. The top engineering minds at SpaceX have agonized over this ... I think we are in a good situation." He went on to explain that the new COPVs now possess the burst pressure "more than twice what they are actually loaded to on the pad."

In future, SpaceX has a backup plan to switch out their carbon fiber tanks lined with aluminum to the "super alloy" Inconel – an alloy of nickel with chromium and iron– but that is unlikely to be necessary, he said.

The rocket has had a lot of success in the last few years. SpaceX has not really had a failure at launch since 2016 when a Falcon 9 exploded into a fireball before launch. Since then, the company has had a launch cadence of 96%.

2018 is likely to be the year when SpaceX finally reaches a rate of one launch every two weeks. There are 28 launches planned for 2018, this includes a few Falcon Heavy launches. There is one planned for the US military in October and one for Arabia in the months following it.