NASA’s Successful Launch, Deployment, and Retrieval of LOFTID – An Innovative Inflatable Heat Shield

On the morning of November 10, an Atlas V rocket launched JPSS-2, NOAA’s newest environmental satellite into orbit. Hitching a ride on the rocket was NASA’s Low-Earth Orbit Flight Test of an Inflatable Decelerator (LOFTID). This mission demonstrated a cross-cutting aeroshell — a type of heat shield — for atmospheric re-entry.

For destinations with an atmosphere, one of the challenges NASA faces is how to deliver heavy payloads (experiments, equipment, and people) because current rigid aeroshells are constrained by a rocket’s shroud size. One answer is an inflatable aeroshell that can be deployed to a scale much larger than the shroud. This technology enables a variety of proposed NASA missions to destinations such as Mars, Venus, and Titan as well as return to Earth.

When a spacecraft enters an atmosphere, aerodynamic forces act upon it. Specifically, aerodynamic drag helps to slow it down, converting its kinetic energy into heat. Utilizing atmospheric drag is the most mass-efficient method to slow down a spacecraft.

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NASA’s Low-Earth Orbit Flight Test of an Inflatable Decelerator, or LOFTID, is demonstrating a cross-cutting aeroshell — a type of heat shield — for atmospheric re-entry. This animation features mission highlights for the launch of NASA’s cutting-edge entry, descent, and landing technology: Low-Earth Orbit Flight Test of an Inflatable Decelerator (LOFTID). Credit: NASA

The atmosphere of Mars is much less dense than that of Earth and provides an extreme challenge for aerodynamic deceleration. The atmosphere is thick enough to provide some drag, but too thin to decelerate the spacecraft as quickly as it would in Earth’s atmosphere. LOFTID’s large deployable aeroshell — an inflatable structure protected by a flexible heat shield — acts as a giant brake as it traverses the Martian atmosphere. The large aeroshell creates more drag than a traditional, smaller rigid aeroshell. It begins slowing down in the upper reaches of the atmosphere, allowing the spacecraft to decelerate sooner, at higher altitude, while experiencing less intense heating.

LOFTID is demonstrating a large aeroshell — 6 meters in diameter or about 20 feet — entry from low-Earth orbit, to demonstrate this technology in conditions relevant to many potential applications. The benefits of using the inflatable decelerator design for a variety of space applications include:

• Low-Earth orbit return; free flyer, in-space manufactured materials [3 to 6-meter scale]
• International Space Station down mass greater than currently possible [8 to 12-meter scale]
• Lower cost access to space through launch vehicle asset recovery [12-meter scale]

The inflatable decelerator technology is scalable to both crewed and large robotic missions to Mars.

On November 10, the launch, deployment, and recovery of LOFTID and its data capsule were successful. Now scientists must evaluate the data captured during the test to learn about the results.

Here is the blow-by-blow recounting of the events on November 10, beginning with liftoff at 1:49 a.m. PST:

Credit: NASA TV

National Oceanic and Atmospheric Administration’s (NOAA) Joint Polar Satellite System-2 (JPSS-2) satellite, with NASA’s Low-Earth Orbit Flight Test of an Inflatable Decelerator (LOFTID) technology demonstration along for the ride, lifted off from Space Launch Complex-3 at Vandenberg Space Force Base in California this morning, Nov. 10! Powered by 860,000 pounds of thrust from the United Launch Alliance Atlas V 401 rocket’s RD-180 engine, launch occurred at 1:49 a.m. PST.

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The United Launch Alliance Atlas V 401 rocket exceeded the speed of sound around a minute into the flight, and soon thereafter reached Max-Q – the moment of maximum dynamic pressure on the rocket. Next up is the booster engine cutoff, followed by the separation of the first and second stages of the rocket.

The United Launch Alliance Atlas V payload fairing containing the National Oceanic and Atmospheric Administration’s (NOAA) Joint Polar Satellite System-2 (JPSS-2) and NASA’s Low-Earth Orbit Flight Test of an Inflatable Decelerator (LOFTID) is inside the mobile service tower at Space Launch Complex-3 (SLC-3) at Vandenberg Space Force Base in California on October 28, 2022. Credit: NASA/Randy Beaudoin

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Booster engine cutoff occurred on time, the first and second stages separated as planned, and the Centaur second stage main engine has started its burn. The payload fairing that protected the JPSS-2 satellite during the first minutes of ascent has jettisoned as expected. The second stage main engine will burn for just over 12 minutes, taking the spacecraft towards the Equator and to low-Earth orbit.

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United Launch Alliance’s Centaur upper stage has successfully powered on the LOFTID re-entry vehicle, kicking off the LOFTID mission sequence. About two minutes after power on, Centaur released the payload adapter that had connected JPSS-2 to the rocket’s upper stage.

Limited data will be received real-time during the technology demonstration. Other milestones are notional given the mission timeline and sequence.

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Aeroshell inflation has started. Once the aeroshell reaches four pounds per square inch (psi) of pressure, Centaur will begin positioning LOFTID for re-entry.

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After orienting LOFTID to an acceptable separation angle, Centaur spun up and released the re-entry vehicle. Spinning at three rotations per minute keeps the LOFTID vehicle stable and pointed in the right throughout re-entry.

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At this time, the aeroshell should have reached a full inflation pressure of 19 psi. LOFTID is only sending limited real-time data during the demonstration. Full data, including confirmation of the final inflation pressure, will be confirmed after landing and recovery.

LOFTID is now coasting toward the atmosphere and re-entry is expected to start in approximately 25 minutes.

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LOFTID is fully inflated as it begins it re-entry. Credit: NASA TV

The team was able to visually confirm full inflation of the re-entry vehicle. LOFTID is now estimated to be at about 78 miles in altitude, the point the LOFTID team considers the start of atmospheric re-entry.

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Over the past few minutes, LOFTID’s thermal protection system should have reached maximum re-entry heating, and the inflatable structure should have reached maximum re-entry pressure load.

LOFTID is only sending limited real-time data during the demonstration. Full data, including the maximum heating and pressure load experienced, will be confirmed after landing and recovery.

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According to the team’s predictions, LOFTID should have slowed down to Mach 0.7 — from a maximum speed of Mach 29 — marking the end of the demonstration and data collection. As LOFTID approaches splashdown in approximately 16 minutes, the ejectable data module will jettison and the parachute will deploy.

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Teams confirmed the ejectable data recorder was jettisoned and they have received GPS data on its location. LOFTID’s parachutes are expected to have deployed, preparing LOFTID for splashdown in less than 10 minutes.

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LOFTID has splashed down in the Pacific Ocean hundreds of miles off the coast of Hawaii. Once the aeroshell’s location is determined, the recovery boat will head toward the aeroshell for attempted retrieval. Following retrieval, the team will recover the ejectable data recorder.

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The LOFTID team has visually confirmed the heat shield’s splashdown in the Pacific Ocean. Splashdown occurred a few minutes later than originally thought based on the expected mission timeline.

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LOFTID landed close to the recovery ship. After assessing the situation, the crew aboard the Kahana-II have begun preparation for recovery operations, which will bring LOFTID aboard the vessel. NASA will post updates on the recovery process and the results of the demonstration as more information becomes available.

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The LOFTID heat shield is lifted out of the water onto the deck of the recovery vessel. Credit: ULA

Team members successfully retrieved the LOFTID heat shield from the Pacific Ocean on Thursday morning. With the heat shield on board, the recovery vessel will next head to retrieve LOFTID’s ejectable data module, which contains a backup of the demonstration data that is also stored on the heat shield.

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The LOFTID heat shield sits on the deck of the recovery vessel. After the heat shield was recovered, the team retrieved the small backup data recorder from the water. Credit: ULA

The LOFTID team successfully retrieved the mission’s ejectable data module from the Pacific Ocean on Thursday morning. The data module resembles a large lemon and holds a backup copy of the data recorded during LOFTID’s demonstration. Another copy of the data is stored aboard the heat shield itself, which was already recovered by the team.

The recovery vessel will now make its way back to port. The LOFTID team will analyze the recorded data and inspect the heat shield to assess how the technology performed. Additional updates will be provided as available.

Illustration of Low-Earth Orbit Flight Test of an Inflatable Decelerator (LOFTID). Credit: NASA

NASA’s Low-Earth Orbit Flight Test of an Inflatable Decelerator (LOFTID) is dedicated to the memory of Bernard Kutter – a manager of advanced programs at United Launch Alliance (ULA) who championed lower-cost access to space and technologies to make that a reality. LOFTID is a partnership between NASA’s Space Technology Mission Directorate and ULA to demonstrate an inflatable aerodynamic decelerator, or aeroshell, technology that could one day help land humans on Mars.

Since NASA’s inception in 1958, the agency has relied heavily on rigid aeroshells (a protective shell composed of a heat shield and a back shell), parachutes, and retro-propulsion (rockets) to decelerate people, vehicles, and hardware during orbital entry, descent, and landing operations. The LOFTID demonstration is poised to revolutionize the way NASA and industry deliver payloads to planetary destinations with atmospheres.

After more than a decade of development of Hypersonic Inflatable Aerodynamic Decelerator (HIAD) technology, including two suborbital flight tests, the LOFTID orbital flight test is the next step. This return from orbit demonstration provides an entry environment relevant to many potential applications, paving the way for its use on future missions. The LOFTID re-entry vehicle, at 19.7 feet (6 meters) diameter, will be the largest blunt body aeroshell to ever go through atmospheric entry.

When a spacecraft enters an atmosphere, aerodynamic forces – like drag – act upon it, slowing it down and converting its kinetic energy into heat. Using atmospheric drag typically is the most mass-efficient method to slow down a spacecraft. Since HIAD technology is larger than traditional aeroshells, it creates more drag and starts the deceleration process in the upper reaches of the atmosphere, allowing not only heavier payloads, but also landing at higher altitudes. It could additionally be used to bring an unprecedented amount of mass back from low-Earth orbit, including items from the International Space Station. Another significant potential benefit is enabling the recovery of rocket assets for reuse which can reduce the overall cost of access to space.

The HIAD design consists of an inflatable structure that maintains its shape against the drag forces, and a protective flexible thermal protection system that withstands the heat of reentry. The inflatable structure is constructed with a stack of pressurized concentric rings, or tori, that are strapped together to form an exceptionally strong blunt cone-shaped structure.

The rings are made from braided synthetic fibers that are, by weight, 10 times stronger than steel. A flexible thermal protection system insulates the rings from the searing heat of atmospheric entry; LOFTID can withstand temperatures in excess of 2900°F (1600°C). It’s constructed with three layers: an exterior ceramic fiber cloth layer to maintain integrity of the surface, a middle layer of insulators to inhibit heat transmission, and an interior layer that prevents hot gas from reaching the inflatable structure. The flexible thermal protection system is also foldable, packable, deployable, and tailorable. Because it is flexible, it takes up less room in the rocket and allows the design to be scalable.

LOFTID is managed by the agency’s Langley Research Center in Hampton, Virginia, with contributions from various NASA centers: Ames Research Center in Silicon Valley, California; Marshall Space Flight Center in Huntsville, Alabama; and Armstrong Flight Research Center in Edwards, California. NASA’s Launch Services Program, based at the agency’s Kennedy Space Center in Florida, managed today’s launch.