Propellant Loading Campaigns on Three Continents

June 12, 2020

While at Skybox one of my responsibilities was overseeing the propellant loading campaigns for the SkySats, which involved traveling to three different launch facilities on three different continents. A bit over 4 years ago we wrapped up the first commercial LMP-103S loading campaign in Sriharikota, India in preparation for the SkySat-3 launch on PSLV in June 2016. Three months later we're in the jungle of Kourou, French Guiana and then a year after that in Lompoc, USA.

Sriharikota, India


In the last week of May 2016, I flew from SFO to Chennai, India through Dubai. The flight was amazing as it was my first experience flying Emirates Business Class on an A380. After finally arriving in Chennai early in the morning, we packed into an incredibly small car around 9am and started the not far, but extremely long journey to Sriharikota. Total distance is about 100 km, but it took about 4 hours to navigate the roads. Upon arrival at the base, we headed to the check-in/badging office to get our credentials. After completing a huge number of forms and waiting a really long time we got our ID and headed to the Guest House. An interesting quirk of the process was that we had to carry a piece of regular binder paper with various officials' signatures on it to indicate we were allowed to take our laptops with us through the main base gate. This piece of paper ended up being checked every time we came or went from the loading facility.

SHAR Guest House
SHAR Guest House - Bathroom/Shower

After dropping our stuff at the Guest House, we went to SP2-B to begin unpacking the loading equipment. Interestingly, the environmental controls in SP2-B were OFF and, it being May 28 in India, it was about 35C (95F) inside the processing facility. Asking the for AC to get turned ON so we could start transferring propellant the next day took quite awhile.

Around the corner from the Guest House is the Dinning Hall, which is the only on-site food option. It serves three meals a day at specific times depending on who's on base and what schedule you've arranged with the "chef". We were the only team on-site for the majority of our stay, so it was very empty 99% of the time.

SHAR Dinning Hall

After much discussion with the Indians regarding facilities, access, security, and safety procedures we got all the loading equipment setup and began propellant transfer from the shipping containers into the transfer tank on May 31. The overall setup we used is shown below.

Loading Operations Setup in SP2B

On June 1 we began the pre-loading system checkout/health tests, which took all afternoon. Everything was nominal, except that the flight tanks experienced an inadvertent rapid vent due to a mistake with not closing the service valve nut. The system wasn't damaged, but it did add an additional MEOP cycle to the flight tanks and therefore reduced the life cycle margin.

On June 2 the flight load of 10.5 kg of LMP-103S was pushed into SkySat-3 and the system was pressurized for flight to about 18.5 bar(a).

Guiana Space Centre, French Guiana

SkySat-4 to 7

Three months later the whole crew and all the equipment is in Kourou, French Guiana prepping SkySat-4, 5, 6, and 7 for launch on Vega. My flight was probably the most circuitous route possible; I flew out of SFO, to Vancouver, BC then to Montréal, QC then to Fort-de-France, Martinique and finally landing in Cayenne, French Guiana. The drive from Cayenne to Kourou is only about 60 km and there were no pedestrians or cows to dodge this time. The team stayed at Hotel Mercure Kourou Ariatel, which was a huge step up from the Guest House in SHAR.

Hotel Mercure Kourou Ariatel

The processing facility we were in at the GSC, building S5B, was also much nicer than the processing hall at SHAR

SkySats in S5B at GSC
Loading Operations Setup in S5B

Operationally, the major difference between the Vega and PSLV campaigns was the processing of 2 SkySats in parallel while in Kourou. The overall process was same, but we could execute much faster having just gone through it in India and then doing two at a time. The biggest hiccup during the Kourou campaign was losing a piece of lock-wire which dropped down behind the SkySat radiator panel when the service valve lock-wire was cut in preparation for hooking up the test equipment. It took about 2.5 hours of digging around in the satellite with limited visibility and access to find the piece and remove it. No FOD allowed!

Vandenberg, USA

SkySat-8 to 13

About 1 year after Kourou we're back for another loading campaign, but this time at Vandenberg AFB in Lompoc, CA, USA. Here we had 6 SkySats to process in a week for launch on the Minotaur-C vehicle and are working in a pretty run down Building 1555.

Building 1555 Work Area at Vandenberg

Since Bldg 1555 is a general work area, we had to get portable cleanrooms for the processing & loading of SkySat. But there was no AC in the "cleanroom" tent and the internal temperature reached 35C (95F) during the loading & pressurization operations, which was not great.

Building 1555 Work Area at Vandenberg

The final product, 6 loaded and pressurized SkySats all stacked on the launch adapter, is below:

SkySats Stacked on Launch Adapter

Further Campaigns

I was directly involved in the three initial campaigns discussed above, but there were subsequent LMP-103S campagins afterward handled by other people and companies listed below:

SkySat-14, 15Falcon 9Vandenberg, USADec 2018
STPSat-5Falcon 9Vandenberg, USADec 2018
SkySat-16, 17, 18Falcon 9Cape Canaveral, USAJune 2020
SkySat-19, 20, 21Falcon 9Cape Canaveral, USATBD