Aerospace Corp. lays out ‘Launch Unit’ standard for medium small satellites
LOGAN, Utah — Tiny satellites have their own 4-inch CubeSat standard size, and bigger satellites have a size standard as well. But there’s an awkward gap where no one can agree on exactly how big a satellite should be. Until now.
Today The Aerospace Corp. took the wraps off a proposed size and weight standard it calls the “Launch Unit.” According the standard, a Launch-U satellite and its separation system would fill a volume of 45 by 45 by 60 centimeters (1.5 by 1.5 by 2 feet), or about the size of an end table or two carry-on pieces of luggage strapped together. (Or, for that matter, a pirate chest.)
The mass could range from 60 to 80 kilograms (132 to 176 pounds), with a roughly balanced center of gravity, according to a technical paper issued to coincide with the SmallSat Conference here in Logan. For vibration purposes, the payload’s fundamental frequency would have to be above 50 Hz in any direction.
Launch-U builds on the 10-by-10-by-10-centimeter Cubesat standard, which can apply to 1-unit satellites (1U) or bigger satellites (for example, a 6U satellite, which would be roughly 10 by 20 by 30 centimeters). One Launch-U equals roughly 96 CubeSat units.
Like those CubeSat U’s, Launch-U’s can build up like Lego blocks. The nose cone, or fairing, on Rocket Lab’s Electron rocket can accommodate two Launch-U’s worth of payload. A Minotaur I rocket can accommodate five Launch-U’s, and Virgin Orbit’s LauncherOne has room for seven Launch-U’s.
The new unit was developed in cooperation with leading launch providers and logistics companies, including United Launch Alliance, SpaceX, Virgin Orbit and Seattle-based Spaceflight.
“The goal was to create a standard that industry would view as enabling rather than an impediment to growth,” Randy Villahermosa, general manager of Aerospace’s Innovation Initiatives, said today in a news release. “Aerospace was a key broker in making this a reality.”
Aerospace CEO Steve Isakowitz said the Launch-U team’s efforts should “lead to shorter integration timelines and increased access to space.”
The standard should also give satellite operators more versatility in choosing launch vehicles, said Launch-U project lead Carrie O’Quinn, senior project engineer for Aerospace’s Research and Development Department.
“Moving the Launch-Unit satellite from, say, an Electron to a LauncherOne … you can do that seamlessly,” she said.
She said the Launch-U standard also meshes well with the next size up on the satellite scale, which follows a standard known as ESPA (EELV Secondary Payload Adapter). The standard unit for ESPA-class satellites measures 61 by 71 by 97 centimeters, with a weight standard of 180 kilograms (400 pounds).
O’Quinn told GeekWire that the Launch-U standard would be formalized over the months ahead, and then submitted to the AIAA or the ISO to administer.