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It was LOI Day, July 19, 1969, Lunar Orbit Insertion Day when Apollo 11 entered lunar orbit, one day before landing.  LOI Day began 69 hours after launch.  Here’s the day as delineated in the flight plan.  You don’t have to know the acronyms to hear the music.  The timeline is a music score.  Relax and let the sound of it flow through you, and without knowing, you, too, will enter lunar orbit.

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69:00  Post Sleep

 ……O2 fuel cell purge

 ………….. Crew status report

70:10  IMU Realign — P52

 ………….70:30  MNVR to burn ATT

 ………………………..Sextant star CK

 …………………………………….. Guidance align to IMU

LOI minus 5 hrs.  Midcourse Correction 4 

 …….(will be executed only if LOI 1 cannot be targeted to connect MCC 3 dispersions).

………………………..71:30  Activate primary evaporator

………………………….73:00  V66 Transfer CSM state vector to LM slot

……………………………………….Copy LOI 1 P30 maneuver pad

………………………………………..73:30  IMU realign — P52 and drift CK

74:00  Update CSM block data (TEI1 & TEI4)

……………………74:10  Roll to acquire MSFN

……………………………….SPS prethrust P40 (TVC test)

…………………………………………………Roll to burn attitude.

73:25  Pitch up 360 degrees at 0.2 degrees/sec to observe lunar surface.

……………………………….74:45  Go inertial

……………………………………….75:00  CMP — pre LOI 1 systems checks  

75: 25   MNVR to burn attitude

…………………………….Go/no go for LOI 1

 …………………………………….GET Ignition: 75:54:28

…………………………………………No ullage

…………………………………………Burn Time:  5 mine 59.9 sec.

…………………. Orbit:  59.2 X 169.8  Retrograde

…………………………………………………Do not trim

76:00  REV 1

 ……………….SM RCS and SPS MON Check

 ……………… Roll 180 degrees, Pitch down 70 degrees, Yaw left 14 degrees

76:19  AOS

…………LOI 1 burn status report

78:50   Record LOI 2 MNVR pad and block data (TEI 5)

………………..CMP — pre LOI 2 systems monitor

…………………………….79:10  Go inertial

……………………………………….IMU Realign – P52

79:30   Maneuver to LOI 2 burn attitude

………………….. Program 40 SPS thrust

…………………………….Go inertial

……………………………………..Sextant star check

……………………………………………..SM RCS check

 ………………………………………………  Load DAP for 2 jet ullage

80:00  GDC align to IMU

…………LOI 2 GET Ignition :  80:09:30

 …………………………Ullage:  2 jet, 19 sec

………………………………………….Burn Time:  16.4 sec.

 ………………………………………………….Retrograde orbit   53.6 X 65.6

 ………………………………………………… Do not trim

…………………………….SM RCS check

80:30  Roll 180 degrees, pitch down 81 degrees, ORB rate

…………………………..Observe lunar surface

……………………………………..80:37 AOS   Acquire MSFN

………………………………………………………..LOI2 burn status report

80:55   Pressurize the LM

……………………CM/LM pressure equalization

81:30  Prepare for LM ingress

……………………….CMP — Clear tunnel of CM hatch

 ………………………………..Inspect tunnel & docking latches

 ………………………………..remove probe & drogue

LMP — Open LM hatch

 …………………..Verify docking tunnel index angle

                           Intervehicular transfer to LM

 …………………………………….LM entry status checks

………………………………………82:00  Perform housekeeping chores:

…………………………………………………1. Stow helmet stowage bags

………………………………………………….2.  Unstow mirror, checklist and disposable assembly

………………………………………………….3.  Stow interim stowage assembly

………………………………………………….4.  Unstow and configure for use:  16mm/HCEX

CDR — aid LMP as required

……………….83:00  Transfer to LM power

………………………………..Comm activation

……………………………….. S-Band.VHF-B  Voice & TM test

…………………………………Comm deactivation

83:45   Transfer to CSM power

……………………..LMP IVT to CSM

………………………………..Close LM hatch

CMP — Install CM hatch

…………………….Tunnel vent valve — LM PRESS

84:00  O2 fuel cell purge

…………………… CSM presleep/ eat period

85:00   Rest period (9 hours)