GLONASS-M (Russian: ГЛОНАСС-М), also known as Uragan-M (Russian: Ураган-М) (GRAU Index 11F654M and manufacturing code 14F113) are the second generation of Uragan satellite design used as part of the Russian GLONASS radio-based satellite navigation system. Developed by ISS Reshetnev (Reshetnev Information Satellite Systems), it had its debut launch in 2003, and is in the process of being phased out. Its production is expected to finish in 2015 and as of July, 2015, its last launch is expected in late 2017. It is an evolution of the previous Uragan (GRAU Index 11F654) second-generation satellites, improving accuracy, increasing power, extending the design life and adding the FDMA L2OF open signal. The last eight Glonass-M spacecraft in production include new CDMA L3OC open signal.

It used a 3-axis stabilized pressurized bus with two solar panels, a propulsion module and a payload module. At 1,415 kilograms (3,120 lb) these are just 2 kg (4.4 lb) heavier than the previous generation, but have 25% more power 1250 W, 230% more design life (7 years), an additional signal (L2OF) and generally improved accuracy. It uses an on-board computer based on a Russian microprocessor using the VAX 11/750 instruction set (the Angstrem ).

The Uragan-M are usually launched in trios, and due to the close distance, the radios of the thee would interfere with each other, meaning that the ground segment can only command one satellite at a time. Setting sun pointing attitude for power and then Earth pointing attitude for communications for a single unit takes about 5 hours. Since the radio contact window with ground control is between 4 and 6 hours, ground control can not control all spacecrafts in a single pass. The on-board computer in the Uragan-M can put the spacecraft in sun pointing mode autonomously, and does many of the start up processes so the ground segment can take control and process the Earth pointing mode.

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