Chandryaan-4: Updates & Discussion

Gautam

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Feb 16, 2019
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Tripura, NE, India
ISRO is working on the follow up mission to the CY-3 called the CY-4. This is completely separate from the LUPEX mission which is a joint mission with JAXA. CY-4 is going to be a fully ISRO mission.

Tentative date of launch is 2028. Details of the mission are still being firmed up, but enough details exist in public to make a new thread on it.

The broad objectives of the CY-4 mission are as follows:
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As described above the entire CY-4 mission will have 5 modules. The combined weight of these modules will be 6700 + kgs. LVM3 can barely do 3000 kg to TLI. CY-3 weighed 3895 kg. It was ~900kg above the LVM3's TLI capacity. We had to do 5 orbit raising burns just to get it to TLI.

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Pic: Complete CY-4 mission stack. Design is not final & subject to change.

CY-4 will require 2 LVM3 rockets with 4-5 orbit raising burns to get to TLI. The full mission stack has to be broken into 2 composites that will dock once in Earth orbit. Needless to say, SPADEX mission is a pre-requisite for the CY-4.

This is what the 2 composites will look like:
1.
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2.
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I'll post more updates as they come.
 
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Chandrayaan-4 LSR:
10x 820N main engines on DM (this engine seems to be uprated from CY3's 800N engine)
3x 820N engines on AM
Seems like the 2 stacks will be launched 1 month apart.
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