I'm in the process of making some STS missions, and am confused about the way that payload weights are handled. The manual says that any payload attached in the bay will have it's mass automatically added to the shuttle. However, in making these scenarios I've found that this doesn't seem to be happening.
For example:
STS-88:
Weight of the Orbiter + Full fuel in orbit 94960 kg
Attached Payloads: 4 x APFR 400 kg, MiniSat 200 kg, SACA 200 kg, Unity 14600 kg
Launch mass per wikipedia is 119715 kg, so in the scenario file I added PAYLOAD_MASS 9345 to make up the difference. After this edit, the weight of the orbiter in the object viewer is now 104305 kg, and that plus the various payload weights comes out to the correct 119715 kg.
STS-96:
Weight of the Orbiter + Full fuel in orbit 118447
Attached Payloads: APFR 100 kg, OTD 100 kg, Strela 200 kg
Launch mass per wikipedia is 118857 kg, so in the scenario file I added PAYLOAD_MASS 24266 to make up the difference, and now when going back in the sim the orbiter mass + the attached payload masses add up to the correct launch weight.
However, the launch performance does not back this up.
For the STS-88 mission, the shuttle gets up to around 105km before starting to drop back down, and reaches 85k before starting to climb again and get orbital velocity.
For STS-96, which is supposed to be a little bit lighter, the shuttle gets up to around 96k before dropping to around 75k before starting to climb again and get orbital velocity.
So it seems that the various payload masses such as the big heavy Unity module in STS-88 aren't being applied, and the "lighter" STS-96 mission is in fact heavier in the sim because it's payload weight is largely set in the scenario file rather than from the payload attachment.
Both these scenarios are from the ISS pack and use a custom "shuttle bay" object as an intermediate, so the payload items are attached to the shuttle bay which is then in turn attached to the Shuttle Fleet orbiter. Maybe this is what's making the payload masses not be applied?
For example:
STS-88:
Weight of the Orbiter + Full fuel in orbit 94960 kg
Attached Payloads: 4 x APFR 400 kg, MiniSat 200 kg, SACA 200 kg, Unity 14600 kg
Launch mass per wikipedia is 119715 kg, so in the scenario file I added PAYLOAD_MASS 9345 to make up the difference. After this edit, the weight of the orbiter in the object viewer is now 104305 kg, and that plus the various payload weights comes out to the correct 119715 kg.
STS-96:
Weight of the Orbiter + Full fuel in orbit 118447
Attached Payloads: APFR 100 kg, OTD 100 kg, Strela 200 kg
Launch mass per wikipedia is 118857 kg, so in the scenario file I added PAYLOAD_MASS 24266 to make up the difference, and now when going back in the sim the orbiter mass + the attached payload masses add up to the correct launch weight.
However, the launch performance does not back this up.
For the STS-88 mission, the shuttle gets up to around 105km before starting to drop back down, and reaches 85k before starting to climb again and get orbital velocity.
For STS-96, which is supposed to be a little bit lighter, the shuttle gets up to around 96k before dropping to around 75k before starting to climb again and get orbital velocity.
So it seems that the various payload masses such as the big heavy Unity module in STS-88 aren't being applied, and the "lighter" STS-96 mission is in fact heavier in the sim because it's payload weight is largely set in the scenario file rather than from the payload attachment.
Both these scenarios are from the ISS pack and use a custom "shuttle bay" object as an intermediate, so the payload items are attached to the shuttle bay which is then in turn attached to the Shuttle Fleet orbiter. Maybe this is what's making the payload masses not be applied?
