Issue 126

China: Yaogan-40 02 Snaps Into Formation

16 Jul: China successfully raised the average altitude of Yaogan-40 02C (63920) to match that of its siblings, YG-40 02A (63918) and YG-40 02B (63919). As a result the trio are now orbiting in an equilateral triangle formation and able to perform their radio frequency monitoring and geolocation mission. China has…

16 Jul: China successfully raised the average altitude of Yaogan-40 02C (63920) to match that of its siblings, YG-40 02A (63918) and YG-40 02B (63919). As a result the trio are now orbiting in an equilateral triangle formation and able to perform their radio frequency monitoring and geolocation mission. China has followed a similar deployment pattern for its other RF/Geolocation triplet formations, namely the YG-40 01A/B/C (57830, 57831 & 57832) launched in 2023 and its 4 sets of YG-31 triplets.

 

From 8-16 July, China raised the average altitude of the YG-40 02C satellite ~64km (from 787 to 851km). As a result, YG-40 02C is now orbiting at the same average altitude as YG-40 02A and 02B and the rate of RAAN precession is equal for all three satellites.

 

China made this maneuver about a month earlier than I had predicted. For some reason China has established the YG-40 02 formation with only a 0.45° RAAN offset which is about 60% of the 0.75° RAAN offset of the YG-40 01 formation. (see graphic next page).

 

As a reminder, both the YG-40 formations are inclined 86° which will provide improved coverage over the polar regions. The YG-31 satellites are all inclined at 65°. Please see Flash edition 121 for a more detailed comparison.