Megaconstellations 🌍📡🛰️🛰️🛰️🛰️🛰️🛰️ Profile picture
covering the development of Low-Earth Orbit (LEO) satellite constellations, such as @OneWeb, @SpaceX #Starlink, @amazon #ProjectKuiper, @telesat #Lightspeed

Jan 8, 2022, 12 tweets

In response to the @FCC's request from 23-DEC-21 () @SpaceX yesterday submitted interesting clarifications (📄licensing.fcc.gov/myibfs/downloa…) with new details about #Starlink Gen2 revealing it was actually filed with the @itu via Germany (@bnetza). A thread:
1/11

SpaceX laments the FCC's long lead times (original Gen2 filing pending for 1.5y, amendment for 5m) by which it justifies its *much earlier* ITU filing for Gen2 through Germany (p.8) & competitive risks from "asymmetric disclosures" b/c of transparent filing process in the US
2/11

Also worth noting: SpaceX claim it "was one of the last remaining NGSO operators to have been licensed
exclusively through the United States" when in fact its original Gen1 ITU filing was submitted through Norway (C/S: STEAM-1 & STEAM-2) and Gen2 apparently through Germany
3/11

SpaceX clarify that Gen2 will "complement and augment" Gen1 but evade response to FCC's question whether UTs will use both simultaneously, says not necessarily all licensed sats (4,408 Gen1 + 41,116 Gen2 (FCC filing shows only 30k)) will operate "at all times in all areas".
4/11

Interestingly SpaceX no longer mention the VLEO/V-band component of its Gen1 constellation consisting of 7,518 sats at 335-346km altitude authorized by the FCC on 25-OCT-18 (see below & 📄docs.fcc.gov/public/attachm…) 50% of which must be launched by 25-OCT-24 & 100% by 25-OCT-27
5/11

In its response SpaceX also "notifies the Commission that it will pursue Configuration 1 and abandon Configuration 2 proposed in the Amendment" from 18-AUG-21 (📄
licensing.fcc.gov/myibfs/downloa…). Config 1 has a median altitude of 413km vs. 405km (Config 2) & 366km (original config)
6/11

The most ludicrous part of SpaceX's response is its interpretation of Sect 25.159 which prohibits an applicant with a licensed-but-unbuilt NGSO-like system to apply for another constellation. SpaceX says by having launched ≥1 sat its Gen1 constellation is no longer unbuilt.
7/11

Among other technical details SpaceX specify that gateway links (E & Ka band) will now be maintained down to 5° for gateways at >62° lat while user links to the 604 & 614km shells may go down to 5° globally which exacerbates in-line events and associated interference issues.
8/11

Remarkably SpaceX also claim they will start launching Gen2 sats "as early as March 2022" into 43° and 53° inclination and imply they will be using their #Starship launch vehicle based on whose development progress the choice between Configuration 1 and 2 has been made.
9/11

SpaceX clarify "direct-to-station launches" doesn't mean sats will be launched "direct to operational altitude" but "may send satellites directly to higher altitude in infrequent circumstances, such as when SpaceX satellites are included on rideshares of other satellites".
10/11

Lastly, SpaceX confirm Gen2 will have equal or better reliability as Gen1 and unchanged in-orbit lifetime of 5-7y. They now use Conjunction Data Message from 2 independent providers and continue using a risk threshold of 0.001% as trigger for collision avoidance maneuvers.
11/11

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