Featured image: The Delta IV Heavy mobile gantry at Cape Canaveral (Image credit: ULA)

CAPE CANAVERAL, FLORIDA – On January 3rd, SpaceX executives, in an interview, pointed out that they are in the final stages of planning a mobile launch gantry at LC-39A at Cape Canaveral. Such a structure has many uses in preparing rockets for flight. From vertical integration to protection of the booster and payload from the elements, they are useful.

What is a Mobile Launch Gantry?

In the simplest of terms, a mobile launch gantry is a moveable structure that is placed around an upright, or vertical rocket. This structure allows access to the rocket for vertical integration, loading a payload while standing, and also allows for boosters to remain vertical in adverse weather conditions. The gantry will be yet another large structure on the pad which is already dominated by the crew access structure, the lightning shield system, the strongback, and other various structures. The SpaceX mobile gantry will be usable for both Falcon 9 and Falcon Heavy rockets.

How are Mobile Gantries Used and Why does SpaceX Need One?

SpaceX currently practices horizontal integration on all of its payloads in a hangar just off the launch pad. After integration, the booster plus payload is rolled out to the pad horizontally, then lifted into a vertical configuration for launch. This has worked well for SpaceX in the past, but the ability to work on a vertical booster is necessary for some launch types and for post checkout corrections.

The main driver behind a mobile launch gantry for SpaceX is the US Department of Defense. The National Security Space Launch Phase 2 Launch Service Procurement program dictates than any launch services provider must be capable of vertical integration to be eligible to be awarded any of the 30 DoD launches between 2022 and 2027. There are also new inspection requirements and higher mass requirements to the reference orbits in this new phase of launch procurement, which was announced in May. Falcon Heavy already fulfills the new mass requirements. ULA, Northrop Grumman, and Blue Origin are also in competition for these procurement contracts, with ULA already having vertical integration capabilities and their own mobile launch gantry for Delta IV Heavy boosters.

This is why SpaceX needs a mobile gantry at Cape Canaveral and potentially at Vandenburg.

SpaceX also may want a mobile launch gantry. Such a structure would allow rapid turnover for vertically landed boosters, which can potentially be landed directly back on the launch pad. While there are several technical difficulties with such a landing procedure, SpaceX has broken those kinds of barriers before. When Elon Musk, SpaceX founder and CEO, spoke about the desire and necessity of landing and reusing a booster, industry pundits said he was crazy. Then came Dec. 21, 2015.

In May of 2018, Musk stated, “Our goal, just to give you a sense of how reusable we think the design can be — we intend to demonstrate two orbital launches of the same Block 5 vehicle within 24 hours, no later than next year.” It has been more than one year since that statement, but the spirit is still holding. Musk has touted in the past that the BFR, now called Starship, could be used for rapid transport worldwide. If this is to happen, vertical integration capabilities are going to be required, in order for rapid turnaround of the system to be streamlined. While with the Falcon series of booster, horizontal integration can be done fairly rapidly, it is much quicker to roll a mobile launch gantry into place around a vertical booster than lowering the booster, rolling it into the integration facility, performing a horizontal integration, rolling it back to the pad, and raising booster and payload back to vertical for launch.

While the DoD requirements provide a necessity for vertical integration and a mobile launch gantry, SpaceX will most likely use this as an opportunity to further streamline their services and further lower the price of launch, the time frame for launch, and the delay in time between launches.