Author Topic: STS-51F inclination (Read 9290 times)

John2375 · « **on:** 07/23/2007 12:55 am »

I was noticing that STS-51F was inclinded to 49.5 degrees which is kind of "weird" - was that planned or was that as a result of the Abort-to-Orbit they had to do??

Jim · « **Reply #1 on:** 07/23/2007 01:12 am »

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John2375 - 22/7/2007 8:55 PM

I was noticing that STS-51F was inclinded to 49.5 degrees which is kind of "weird" - was that planned or was that as a result of the Abort-to-Orbit they had to do??

Science requirements

John2375 · « **Reply #2 on:** 07/23/2007 01:33 am »

so why is that?
I know some have gone to 39 deg... some to 57.. how does that effect the science?

AstroRJY · « **Reply #3 on:** 07/23/2007 01:47 am »

The inclination changes what trajectory you take and what part of the earth will be seen from space as you orbit. The standard inclination used to be 28.45 degrees which flies over different parts of the planet than a 57 or a 39 degree inclination flight does. The standard now is 51.6 degress because that's the path to take to reach the ISS. Hope that contributes something helpful.

Jim · « **Reply #4 on:** 07/23/2007 02:26 am »

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John2375 - 22/7/2007 9:33 PM

so why is that?
I know some have gone to 39 deg... some to 57.. how does that effect the science?

repeating ground tracks, max ground coverage,

John2375 · « **Reply #5 on:** 07/23/2007 11:37 am »

OK, I understand that, i think.. like for the radar mapping missions I know why they were at 57, to cover as much earth as possible w/a safe launch ascent.. but I thought STS-51F was Spacelab 2 with everything "inside", so why would they need to be highly inclined??

Jim · « **Reply #6 on:** 07/23/2007 11:43 am »

Spacelab-2 (51-F) was all pallets and no module, so no "inside"

John2375 · « **Reply #7 on:** 07/23/2007 11:46 am »

OK Thanks!! I appreciate that!!

brihath · « **Reply #8 on:** 07/23/2007 12:38 pm »

In reviewing the experiments package aboard Spacelab 2, the focus was primarily on astronomy, solar physics and atmospheric plasma physics. The atmospheric plasma physics package may have dictated the orbital inclination, as this mission was the first to go to an inclination that high. There was some discussion in the press release about interaction with ground based stations and a satellite released from the orbiter. The higher inclination would have provided greater ground coverage. There weren't any specifics about the reason for the inclination in the original press release.

psloss · « **Reply #9 on:** 07/23/2007 12:48 pm »

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brihath - 23/7/2007 8:38 AM

In reviewing the experiments package aboard Spacelab 2, the focus was primarily on astronomy, solar physics and atmospheric plasma physics. The atmospheric plasma physics package may have dictated the orbital inclination, as this mission was the first to go to an inclination that high.

Spacelab 1 (STS-9) was the first and went to 57 degrees inclination.

brihath · « **Reply #10 on:** 07/23/2007 12:56 pm »

My bad- thanks for the correction.

psloss · « **Reply #11 on:** 07/23/2007 01:04 pm »

FWIW, the press kit for 51-F says:

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Insert into 186 by 106 n. mi. (direct insertion) orbit, then maneuver to approximately 207 n. mi. circular with 7 OMS maneuvers, which also are required to meet the Plasma Depletion Experiment requirements for a ground track that passes over specific ground sites.

It and others are here:
http://www.jsc.nasa.gov/history/shuttle_pk/shuttle_press.htm