The Progress MS (Russian: Прогресс МС; GRAU: 11F615A61) is the latest version of the Russian Progress spacecraft series, first launched in 2015. The "MS" stands for "modernized systems," reflecting upgrades primarily focused on the communications and navigation subsystems. An evolution of the Progress M spacecraft, the Soyuz MS features minimal external changes, mainly in the placement of antennas, sensors, and thrusters. It is used by Roscosmos for cargo spaceflight missions. Progress MS-01 conducted its maiden flight on 21 December 2015, heading to the International Space Station (ISS).
Design
Like all previous variants, the Progress MS spacecraft consists of three distinct sections:[1]
Cargo Section: This pressurized carries supplies for the crew, including maintenance items, prepackaged and fresh food, scientific equipment, and clothing. Its docking drogue, similar to that of the Soyuz, features ducting that enables fuel transfer (described below).
Tanker Section: Replacing the Soyuz’s reentry module, this unpressurized compartment houses two tanks containing unsymmetrical dimethylhydrazine (UDMH) fuel and dinitrogen tetroxide (N2O4) oxidizer. Ducts run from these tanks around the outside of the pressurized module to connectors at the docking port, allowing automated fuel transfer. This design prevents any potential leaks of the toxic propellant from contaminating the station's atmosphere. This section also contains water tanks.
Propulsion Section: Located at the rear of the spacecraft, this unpressurized compartment remains largely unchanged from the Soyuz design. It contains the orientation engines used for automatic docking and can be utilized to boost the station's orbit once docked.
The Progress spacecraft’s uncrewed and disposable design enables significant weight reduction. Unlike Soyuz, it does not require life support systems, heat shields, parachutes, or automatic crew rescue systems. Additionally, it lacks the ability to separate into multiple modules. after completing its mission, the spacecraft undocks, performs a controlled retrofire, and burns up upon reentry into Earth's atmosphere.
Total payload capacity at launch: 2,600 kilograms (5,700 lb) – the following amounts exceed this capacity, giving planners the ability to match the payload to the needs of the station
Dry cargo (in cargo section): Up to 1,800 kilograms (4,000 lb)
Propellant: Up to 870 kilograms (1,920 lb)
Water: Up to 420 kilograms (930 lb)
Gases: Up to 50 kilograms (110 lb)
Total payload capacity (in cargo section) for disposal: 2,140 kilograms (4,720 lb)
Progress MS improvements
The Progress MS received the following upgrades with compared to the Progress M:[2][3][4][5]
New flight control system (SUD): Instead of relying only on six ground stations to determine its orbital path, the new SUD flight control system will also use signals from GLONASS navigation satellites.
New Kurs-NA rendezvous system: The new Kurs-NA (Russian: Курс-Новая Активная, romanized: Kurs-Novaya Aktivnaya, lit. 'Course-New Active') automatic docking system is designed and manufactured in Russia, replacing its Ukrainian predecessor. This change addresses a political problem (with the two countries at war) and enhances the system’s capabilities with a higher level of computerization. While the original Kurs system was highly reliable over the years, many of its electronic components have become outdated. The Kurs-NA is 25 kg (55 lb) lighter, 30% smaller, and consumes 25% less power. Additionally, it features a single phased-array antenna, replacing four antennas on the older system, while the two narrow-angle antennas have been retained although re-positioned further toward the rear. To assist with docking, the old halogen headlight has been replaced with a brighter, more energy-efficient LED light.[6][7]
Unified Command and Telemetry System (EKTS, Russian: Единая Командно-Телеметрическая Система, romanized: Edinaya Komandno-Telemetricheskaya Sistema): Instead of solely relying on ground stations in Russian territory, the spacecraft has a satellite-capable communications system, EKTS, that connects to Russia's Luch system, providing coverage 83 percent of the day. It also retains very high frequency (VHF) and ultra high frequency (UHF) radios for communications with ground stations. The large EKTS S-band satellite antenna array, one of the most prominent new features on the ship's exterior, is also capable of communicating via American TDRS and Europe's EDRS satellites. The EKTS integrates several previous systems, including the BRTS (radio), MBITS (telemetry), and Rassvet (radio voice), which have been replaced or upgraded for compatibility. Additionally, it features a COSPAS-SARSAT transponder for real-time location tracking during reentry and landing. These changes enable the Soyuz to use the same ground segment terminals as the Russian Segment of the ISS.[8]
Additional micro-meteoroid protection: Additional anti-micro-meteoroid shielding was added to the cargo section module walls. This measure was designed to safeguard the spacecraft's most vulnerable component against the unlikely but potential threat of a meteoroid or space debris impact.
Improved docking mechanism: The docking system received a backup electric driving mechanism.[9]
Digital camera system: The spacecraft utilizes a digital television camera system based on MPEG-2, replacing the older analog system. This upgrade enables space-to-space RF communication between the spacecraft and the station and reduces interference.
CubeSat deployment platform: New external compartment that enables it to deploy CubeSats. Each compartment can hold up to four launch containers. First time installed on Progress MS-03.
