apollo 11 moon landing longitude latitude from PDI to Touchdown

Question

I'm reconstructing the entire apollo 11 mission trajectory.

I'm now at the moon landing. Does someone know specific documents specifying longitudes and latitude at the different interfaces starting from the Power Descent Initiation to the Touchdown. I don't need the entire lon / lat history, just the values at the interface points (e.g., at PDI, end of braking phase, end of approach, etc.)

I found the NASA TN D-6846 (Apollo Experience report - Mission Planning for Lunar Module Descent and Ascent), but specific numbers are not given.

"Apollo by the numbers" does not have that either.

Any extra reference you might know?

Thanks!

Edit: although the question here seems similar, the replies and the references given to that question are not specific enough (e.g., lon / lat at the end of breaking and approach phase are not really specified) or not relevant (apollo 8 that is mentioned there did not have any lunar landing phase), therefore I'd like to keep this one open in case someone has more specific details not found over there.

Does this answer your question? If I wanted to reconstruct an entire Apollo mission's crewed spacecraft trajectories, what are the key sources of historical data I'd look for? — Organic Marble, Apr 02 '20 at 03:54
@Topcode the altitude is in there. But longitude and latitude are only roughly shown. — venom, Apr 02 '20 at 03:55
Hi @OrganicMarble Brauenig covered mostly the ascent part. The mission report with the table is useful, thanks, (I already had a look at it) but there is only PDI lon / lat, not the intermediate points until the landing. And I'm not completely sure it is 100% accurate (for example at the PDI it gives a positive fpa of 0.03°, while it should be negative instead) — venom, Apr 02 '20 at 03:59
There's another question on the site asking for landing traj data (I think asked by Borogove) but I couldn't find it before I shut down my real pc. I don't think it had an answer though. — Organic Marble, Apr 02 '20 at 04:43
Hi @venom someone has already voted to close your question as duplicate because they believe that the answer to your question can be found there. I see that you've replied already that it can't, but if you can edit your question and make a note that you've seen those answers and explain why they are not sufficient to answer your question, that would be great. Ideally your question won't be closed but sometimes people don't look at comments. Thanks! — uhoh, Apr 02 '20 at 04:53
Related: https://space.stackexchange.com/questions/40829/source-for-apollo-11-descent-time-series-data — Russell Borogove, Apr 02 '20 at 17:04

score 7 · Answer 1 · answered Apr 02 '20 at 05:59

The parameters for the Apollo lunar descents are too complicated to explain here. However, the entire May-June 1972 issue of the Bell System Technical Journal volume 51 number 5 (30 Mb pdf, 176 pages) was devoted to documenting the planning of the Apollo program.

Pages 1046 to 1048 describe the descent trajectory. It includes these pictures:

Appendix B has the descent trajectory details, the guidance equations, and graphs of thrust and pitch as a function of time.

Enjoy!

Hi @DrSheldon, thanks! I already knew the figures above, but not the report you mentioned. I'll check it out! — venom, Apr 02 '20 at 07:13

score 4 · Answer 2 · answered Apr 02 '20 at 16:58

The Apollo 11 Mission Report (MSC-00171 of 11/1969) claims for PDI:

1.037º latitude, 39.371º longitude @ 49,376 feet (best estimate; primary guidance computer had slightly different values)

(Table 5-III, p 5-14).

The document also gives no less than 8 different sets of landing coordinates from different sources (table 5-IV, 5-15).

There's a lat/long/altitude chart for the lunar ascent phase on p 5-37, but I don't see one for descent.

apollo 11 moon landing longitude latitude from PDI to Touchdown

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