ST. JOHN’S, Newfoundland – A SpaceX Falcon 9 rocket on Aug. 14 successfully placed the JCSat-16 commercial telecommunications satellite into geostationary transfer orbit and landed the rocket’s first stage on a drone ship in the Atlantic Ocean.

Satellite builder Space Systems Loral reported the satellite was healthy in orbit and sending signals after separation from the Falcon 9 some 33 minutes after launch from Cape Canaveral Air Force Station, Florida.

The launch appeared as a repeat of SpaceX’s May 4 liftoff of the JCSat-14 satellite, also owned by Sky Perfect JSat of Japan, which successfully landed the first stage. That stage has since been test-fired three times at SpaceX’s Texas facility as the company accumulates data on how its first stages perform after reentry and landing.

Hawthorne, California-based SpaceX hopes to reuse a first stage this year, although the company has not announced a customer. SES of Luxembourg, which has two satellites scheduled for SpaceX launches late this year, is the most logical inaugural customer for a reused first-stage engine.

For Sky Perfect JSat, the JCSat-16 launch carried an unexpected importance. Intended as an in-orbit spare, the satellite will now be deployed to 162 degrees east in geostationary orbit to replace the aging Superbird-B2 satellite, launched in 2000.

JSat’s Superbird-8/DSN-1 satellite, carrying a Ku-/Ka-band commercial telecommunications payload and an X-band payload for Japan’s Defense Ministry, was damaged during transit to Europe’e spaceport and will require more than a year of repairs and retesting. Superbird-8/DSN-1 had been the intended Superbird-B2 replacement.

For unclear reasons, Sky Perfect JSat did not want the launch mass of JCSat-14 or JCSat-16 to be made public. But industry officials said JCSat-16, carrying an all-chemical propulsion system, weighed around 4,600 kilograms.

A very crowded SpaceX manifest to the end of the year

The launch was the eighth of the year for Hawthorne, California-based SpaceX, which is confronting a list of at least nine missions whose owners in recent weeks have confirmed that they expect their launches to occur by December.

SpaceX officials said early this year they hoped to conduct 18 launches in 2016 from both Cape Canaveral and Vandenberg Air Force Base, California, which is used for missions to high-inclination low-Earth orbit.

The following list of satellite owners who have informed their investors of scheduled 2016 launches is subject to change and does not include the inaugural SpaceX Falcon Heavy vehicle.

SpaceX President Gwynne Shotwell said Aug. 9 in a presentation to the Small Sat 2016 conference that Falcon Heavy, originally scheduled for launch in 2013, was proving to be “actually a harder problem than we thought.”

Falcon Heavy more challenging than expected

After apologizing to customers for the delays, Shotwell said: “I’m president: There’s three [Falcon 9 first stage] rockets. You glue them together. How hard is that? Well, according to my team, it’s really hard.” She did not specify an inaugural-flight date.

The 2016 manifest assumes that London-based Inmarsat moves its Inmarsat-5 F4 to an International Launch Services Proton rocket to assure a 2016 launch. But Proton, like SpaceX, has faced delays in recent months and its next launch is now set for October. How many missions it can fit in before the end of the year is unclear.

Some of these satellite owners are more worried than others about any further delays at SpaceX because of business issues including current in-orbit capacity, customer in-service expectations or regulatory deadlines.

Nine missions awaiting SpaceX launches this year

Customers expecting a launch this year on Falcon 9 vehicles:

— Spacecom, Amos-6. Launch is currently scheduled for Sept. 3-4. An in-orbit failure of a Spacecom satellite has put pressure on the company to shore up its revenue base and customer set and to launch Amos-6 as soon as possible. It’s already late.

— EchoStar Corp., EchoStar-23. EchoStar told investors to expect a launch in October.

— SES, SES-10. The Luxembourg fleet operator was an early SpaceX supporter and has two satellites slated for launch on Falcon 9 this year. SES-10 is set to go first, and has substantial incremental capacity that SES is counting on to drive revenue growth late this year.

— SES, SES-11/EchoStar-105. This satellite, part of commercial agreement with EchoStar, is perhaps the most likely inaugural customer for a reused Falcon 9 first stage because it is intended to replace capacity in orbit.

SES has said it wants a substantial discount on SpaceX’s already low price in exchange for being the first customer. But SES has made clear to investors that regular use of partially reusable rockets is a key component of SES’s strategy for reducing capital spending. SES insurance underwriters have said they will not insist on major premium increases to cover a launch with a reused first stage.

— NASA, Dragon CRS-10 cargo-transport mission to the International Space Station, now scheduled for November.

— KT Corp. of South Korea, Koreasat-5A. The company has told investors the launch should occur before the end of this year.

In addition the above launches from Cape Canaveral, SpaceX has three launches scheduled from Vandenberg.

— Iridium Communications, Iridium Next 1-10. The first 10 satellites for Iridium’s second-generation constellation is now scheduled for mid-September.

— National Space Program Office (NSPO) of Taiwan, Formosat-5; and Spaceflight Inc.’s Sherpa small-satellite tug. Repeatedly delayed, this launch is scheduled for late this year. But in a launch manifest crowded with customers whose businesses depend on mission timing, NSPO may find it hard to maintain its slot.

— Iridium Communications, Iridium Next 11-20. For insurance and satellite-validation reasons, Iridium needs to wait three months from the first launch to the second. Assuming a successful launch of the first 10 satellites, a slip into early 2017 would not do damage to the company.