Author Topic: Atlas V 541 - NROL-42 - VAFB SLC-3E - Sep 24, 2017 05:50 UTC (Sep 23 2250 PDT)  (Read 51914 times)

Offline jcm

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  • Jonathan McDowell
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I hadn't spotted this before or seen discussion about it: the Enhanced Polar System USAF comms package EPS-2
probably flew on this mission

(text attached)
SMC plans to purchase two additional EPS EHF XDR payloads to prevent a MILSATCOM
mission gap in the Polar region. SMC is pursuing a near-term hosted payload
option to be launched in Calendar Year (CY) 2022 to satisfy EPS mission

Global protected SATCOM will be provided in the near-term by two complementary 
space systems. The Advanced Extremely High Frequency (AEHF) system currently 
provides protected SATCOM services for both tactical and strategic users in
mid-latitude regions (65S to 65N). The EPS will soon provide protected SATCOM
for a small number of tactical users in the North Polar Region (65N to 90N).ng
Both AEHF and EPS provide protected SATCOM employing XDR payloads utilizing the
EHF band.

EPS payloads are currently hosted on another organization's space vehicle. EPS-1
is currently on orbit and EPS-2 will be available for testing in late CY17. The
EPS ground segments includes a payload control and mission planning element
located at Schriever AFB and a Northern Tier SATCOM Gateway located at Clear AFS,
which provides DoD Information Network (DoDIN) connectivity via the Camp Roberts

I think we may conclude that EPS-1 was on NROL-35 and EPS-2 on NROL-42.
We know the IPS (Interim Polar System) flew on earlier TRUMPET type missions

Jonathan McDowell


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