Today is the day you have been waiting for your entire life. You are about to begin an extraordinary adventure few humans have even believed possible. You stand on the shoulders of over 400,000 men and women who have worked toward this one event. This day more than 100,000 people are directly preparing to send you off on your journey. Strap yourself in, the adventure begins now…… you are going to the MOON!!!
Your expedition had begun 20 months earlier and required thousands of people to prepare the launch vehicle, spacesuits, provisions, instruments, and planning for your three-day excursion on the lunar surface.
But as you may know, traveling to the Moon is very risky business...
You awaken 4 hours and 15 minutes before launch and taken to see your flight surgeon. You are greeted by your favorite nurse, who proceeds to give you a brief physical exam. Your flight surgeon follows up with a slightly more thorough look-over and gives you the ok to fly. You know you’re healthy, but this was NASA’s last chance to cancel your adventure. You breathe a sigh of relief.
You are taken to a breakfast area and fed steak and eggs, coffee and orange juice. This meal is considered traditional, but it is also low in residue. Your first day is real busy, not a lot of time for personal hygiene issues.
Next you are taken to a large open room where you will suit up. Several technicians are there to help you don your space suit.
They put you in your one piece constant wear garment. This garment is like long johns, but with biometric sensors built in for monitoring your heart and respiration. You’ll wear these for the better part of your 12 day mission. The gas-retaining pressure bladder is next, and then the outer structural beta-cloth restraint layer. A communication carrier (“Snoopy hat”) is placed on your head. This device has redundant microphones and earphones and is worn with the pressure helmet.
Your suit is pressure tested to be sure it is airtight. If you pass the pressure test you’re sealed in and given a hand held portable supply of pure oxygen.
You and your two crew members are escorted to a large van and driven to the launch pad, self-sealed in your own atmospheres.
Three hours before launch you arrive at the 320 foot level of the launch umbilical tower. This is the ninth and highest umbilical arm that leads to the “white room” where a crew of technicians will strap you and your two crew mates into the spacecraft couches in the Command Module (CM). This procedure is called Astronaut Insertion.
You are the commander so you will enter the command module first. You will sit in the left couch where you will have the best view of instruments that indicate your launch trajectory. As the commander, only you can manually abort the mission by twisting the translation control in your left hand. The instrumentation before you will also allow you to manually direct the launch vehicle into orbit, if necessary. At this moment, you literally have the fate of the mission in your hands.
Your crew mate the Lunar Module Pilot (LMP), enters next and takes the right seat, followed by the CMP (Command Module Pilot) taking the center seat. The pad team pulls your restraining straps tight, seals the cabin hatch and retreats to a safe distance from the vehicle.
Five minutes before launch the umbilical arm supporting the afore mentioned white room is swung away to the opposite side of the launch tower. You and your crew are busy following your checklist at this critical moment in your journey.
Twenty seconds before launch the internal navigation system, of the Saturn 5 rocket, confirms your known position on the Earth, and aligns the CM guidance platform.
8.9 seconds before launch, the first stage of the Saturn 5 rocket begins the ignition sequence for the five F-1 engines located at its base. All five engines attain full thrust one second before launch. At full thrust, the five F-1 engines will consume more than 13 tons per second of kerosene and Liquid Oxygen (LOX). This fuel consumption will continue for the entire 2 minutes and 39 seconds the first stage is in use. The output power of the first stage Saturn 5 rocket happens to equal the peak electrical demand of the United Kingdom for that amount of time.
One second before launch, the Saturn 5 computers decide the five F-1 engines are at full thrust. Four hold-down arms are released pneumatically, and your vehicle is free to fly. 10 seconds later your rocket clears the top of the launch tower.
You are shaken by vibrations in almost every direction. Your fellow astronauts had described this ride as like riding an old freight train going down a bad track. You are aware of the abort handle in your left hand, so you relax your grip. You wouldn’t want to accidentally activate an abort because of this rough ride!
Soon after the Saturn 5 clears the launch tower, the four outboard engines of the first stage begin to gimbal and steer the entire rocket from a vertical position, to a very gradual horizontal position. This steering causes you to have another unusual sensation of motion. As your acceleration increases, the g-forces increase also.
You are 2 minutes and 30 seconds into the first stage burn, and you have accelerated to 4g’s. You have been pushed deeply into your couch and you know the first stage rocket has almost exhausted its fuel. You prepare for the first stage to shut down and staging to begin.
When your vehicle lifted off it weighed over 6,500,000 pounds. 2 minutes and 38 seconds later it weighs less than 1,900,000 pounds. You are at an altitude of 37 miles traveling at 5,300 miles per hour. Your acceleration is at 4g’s and then, BAM, staging occurs! Your vehicle is cut in half by an explosive cord. The second stage rocket starts its five engines one second later and you continue on your way to low earth orbit. The first stage rocket slowly falls toward the Atlantic Ocean below. Bye bye, first stage rocket.
At staging the vehicle goes from 4g’s to zero g’s instantly. The entire compressed stack of the remaining rocket unloads its entire length, and stretches out in the opposite direction all at once. You, being at the end of this stack, feel like you are going through the instrument panel! Then, one second later, the five engines of the second stage fire, forcing you back into your couch for more acceleration. You are holding the abort handle at its base, praying you don’t do the wrong thing.
The second stage has five J-2 engines configured similarly to the five F-1 engines of the first stage. The J-2 rocket engine combusts Liquid Oxygen (LOX) and Liquid Hydrogen(LH2). The reaction of hydrogen and oxygen is a powerful source of rocket thrust. The exhaust from this reaction is superheated steam.
After such a violent staging event, your realize things have really smoothed out. You accelerate for the next 6 ½ minutes to just over 2g’s. Then the second staging event occurs. This time you feel a jolt forward, but not nearly as severe. Bye bye, second stage rocket.
Your vehicle now weighs only 380,000 pounds. You are at an altitude of 94 miles and traveling at 14,637 miles per hour. The third stage rocket consists of a single J-2 engine that will complete your insertion into low earth orbit. This rocket engine is almost identical to the J-2 engines on the second stage, with the exception it can be restarted.
Two minutes and twenty five seconds after starting the third stage, you are finally at the velocity for low earth orbit. The third stage rocket engine shuts down. Your vehicle now weighs only 310,000 pounds. You are at an altitude of 94 miles and traveling at 16,557 miles per hour. You congratulate your fellow astronauts. You are thankful for all the hard working men and women that made this engineering marvel possible. You have gone from zero miles per hour to over 16,000 miles per hour in twelve minutes!
You are now in a micro gravity environment. You have plenty to do. The command module and its service module need to be completely checked out in the next two hours. If everything checks out OK, the third stage rocket will restart and burn for 6 minutes. This thrust will accelerate the vehicle to a speed of 25,000 miles per hour, which is the velocity your vehicle needs to go to the moon.
You are now two hours an fifty six minutes into you mission. Mission Control has informed you your vehicle is healthy and you're go for Trans Lunar Injection (TLI).. You restart the third stage J-2 rocket motor. Six minutes later the engine shuts down.
The Lunar module is cradled in the third stage rocket. It must be removed from the third stage and docked with the command module. This maneuver is called transposition
The CM will separate from the third stage rocket, turn around 180 degrees, go back to the third stage and dock with the Lunar Module. The command module will then pull the LM from is cradle, and move away from the empty third stage rocket. This connected stack of the CM and the LM will take you and your crew 240,000 miles into lunar orbit.
The fuel exhausted third stage will be remotely directed by Mission Control to crash into the moon. The third stage rocket will impact the moon and send data collected by the seismometers back to Earth. Previous missions of astronauts have left the seismometers on the moons surface. Geologists back on Earth decode these signals to determine the internal structure of the moon. How cool is that? Bye bye, third stage rocket.
You are now four hours and thirty nine minutes into your adventure. For the next three days you will fall all the way to the moon through the vacuum of space. What an adventure. Of course the real adventure will be landing on the moon!
You are into the 104th hour of your mission. You have traveled the 240,000 miles of space between the Earth and the Moon, and you are now in orbit around the moon.
You are in an lopsided elliptical orbit around the moon. The high altitude of this orbit is 60 miles. The low altitude of this orbit is about 9 miles, a mere 50,000 feet! At the low point of this orbit, you look out the CM window. What you see are mountains that surround your landing site. As you watch, the landing site goes whizzing by at 3,730 miles per hour. You are so close to the surface you instinctively close your eyes and lift your feet!
You see a small valley surrounded by mountains. The mountains rise above the lunar surface by 20,000 feet. Inside the valley are craters and many other odd features. These odd features interested the scientists back home enough to decide to land your Lunar Module (LM) here. You realize that in the next four hours you will either land in this valley, crash in this valley, or be forced to abort your landing.
You say "see you later" to the Command Module Pilot (CMP), because he stays behind in lunar orbit. You enter the LM spacecraft, with the Lunar Module Pilot (LMP), through a tunnel that connects the two vehicles. You close the hatch tightly behind you.
You assume the control station at the left side of the vehicle. As the commander of this mission you will be in control of the LM all the way down to the surface. Your primary job is to choose a landing area smooth enough to safely land the LM. The last 2 minutes of the landing require the LM will be in a manual control mode. You will be in complete control of where the vehicle finally sets down on the lunar surface.
Your LMP assumes the right control station in the LM. His primary job is to watch the instruments and verbally inform you of the altitude and velocity of the vehicle as you approach the landing site. He is also responsible for updating the rendezvous radar and other instruments in case you must abort the landing.
Both of you don your helmets and pressurize your space suits to 3.7 pounds per square inch at 100% pure oxygen. You check each other for leaks in your suites.
You both connect cable restraints to hasps around your spacesuit waist. The cabin of the LM has no seats. You will control the spacecraft standing on your feet. The cable restraints are like seat belts in your car. Normal movement is allowed, but if there is a sudden jolt the cable restraints will lock and hold you in place. You each have one window to look through. Because you are standing, your face is very close to the glass. This position gives you an excellent view of where your craft is going.
You operate the controls to disconnect the LM from the Command Module, and the LM is free to fly on its own. You use the LM thrusters to precisely back away from the CM by 50 feet and stop. You push a button to release and lock the four landing legs of the LM. These legs have been in a folded position during transport from Earth. The CM pilot looks out his window and confirms, by radio, the landing legs are in the correct position and locked in place. You and your LMP are ready to land!
At this time, both vehicles are at the high point in your lopsided orbit which is 60 miles. Both vehicles are now plunging down to the low point of the orbit, which is only 50,000 feet above the surface of the moon.
12 minutes before you reach the low point in your orbit the navigation computer will start the LM decent rocket engine. The rocket thrust will be in the opposite direction of your travel, so you will begin to slow down and eventually impact the lunar surface. Two minutes short of impact, you will take manual control of the LM and gently set it down in the center of the valley. You will throttle the decent rocket engine and hover the LM until you find a suitable landing site. That’s your plan anyway.
The CM will continue to orbit the moon as before. Eventually the CM will establish a more circular orbit of 60 miles by 60 miles, and wait for your return rendezvous in three days.
In a perfect landing you will set down 12 minutes after the decent engine starts. The decent stage of your vehicle holds 14 minutes of fuel for landing. This means you only have 2 minutes of extra fuel to hover and find a smooth landing surface. You think to yourself, no problem. That’s plenty of time right?
You and your LMP are in a horizontal position in the LM. You are essentially flat on your back looking out your window into the blackness of space. You cannot see the moons’ surface. You have this attitude because the decent rocket engine is below your feet and must provide deceleration thrust opposite of your direction of travel.
12 minutes before you reach the low point of your orbit, the navigation computer starts the decent engine. The engine comes up to 10% thrust for 30 seconds and the engine nozzle gimbals around to find the exact center of gravity of the LM. The engine then increase thrust to 92.8%, which is considered full power. Your body feels the deceleration and your restraining cables keep your feet on the floor of the vehicle. For the next 9 minutes not much happens until you notice the peaks of the mountains fill the left side of your window. You realize you are about 20,000 feet above the surface of the moon. You still are in a horizontal position and cannot see where you are going. You can only see the mountains fill the side of your window as you lose velocity and descend downward.
The LM landing radar locks on to the surface and the computer now updates your altitude and velocity accurately. This is a great relief, because if the landing radar does not work you would have to abort the landing.
When the LM is at 7,000 feet, small thrusters on the vehicle fire to pitch the LM upright in a vertical position. You can now see exactly where you are headed and have a clear view of the landing site.
When the LM is at 1,000 feet you code the computer for manual control of the vehicle. A light illuminates on the control console, and your LMP notifies you that 12 minutes have elapsed. You now have 2 minutes of fuel to hover and land. No pressure.
You realize if you stay on this course you will land in a large bolder field. You reduce your downward velocity and increase your horizontal velocity to move to another location. You see a smooth area ahead and commit to land there.
You then increase your downward velocity so you can land quickly, while slowing your forward motion to almost nothing. You are now falling straight down. Your LMP calls out 200 feet and dust fills your window and reduces your visibility. Your LMP calls out your altitude at 100 feet, and you realize you are totally on instruments, because you can see nothing but dust outside.
There are 6 foot metal probes on the bottom of the landing pads of the LM. When any one of them touches the lunar surface they signal the LMP of surface contact. Your LMP calls out "contact" and you push a button to shut down the decent rocket engine.
Your vehicle free falls the last 6 feet to the surface. You feel the shock absorbers on the landing legs cushion the fall in the lower gravity of the moon. Instantly all the lunar dust outside your vehicle falls, and the view out your window is absolutely crystal clear. You have landed on the moon!
You’re 163 hours into your lunar mission. You have landed on the moon, and completed two days of surface operations. You are now preparing to start your third and final moon walk. Your LRV (Lunar Roving Vehicle) has traveled 12 miles in the last two days, and you plan to travel an additional 6 miles today.
You look around the LM cabin and once again amazed that two men could live in such a confined space. The habitable volume for both of you is only 160 cubic feet. This space includes storage for you space suites, PLSS (Personal Life Support System) backpack, Moon rock storage boxes, food and other necessities. It’s only for three days, and you know you can do it.
You both have slept in hammocks suspended above the LM floor, and sleeping in one sixth gravity was very comfortable. Moon dirt litters the floor of the LM. In some place piled centimeters deep. The moon dirt is almost charcoal black and smells like spent gun power. It’s more than a nascence, it can cause harm to the delicate control and instruments.
You have removed you constant-wear garment and replaced it with your Liquid Cooling garment. It is a knitted spandex garment with a network of plastic tubing through which cooling water from the PLSS circulates. It is worn next to the skin and replaces the constant-wear garment during Lunar Surface EVA (Extra Vehicular Activity).
Your space suites are filthy. You tried to brush the dust off outside the LM but the vacuum on the moon causes the dust to stick to the outside of your suit. The round connectors for you helmet and gloves need to be wiped clean and lubricated with lite oil to work properly and seal your suites. Once you are both suited up, you check each other for leaks.
The depress valve is opened and the oxygen inside the LM is vented into space. When the cabin is in a vacuum, you open the door hatch. You get on your hands and knees and back yourself on to the LEM porch. You carefully find the first step and lower yourself down the latter to the lunar surface. Right behind you is the LMP (Lunar Module Pilot).
You and the LMP load the rover with your equipment and start driving in the westerly direction. The sun is low in the lunar morning and at your back. There are no contrasting shadows to show where the craters are in front of you. You drive slowly to avoid driving into a 200 foot deep crater! After 2 and ½ miles you arrive at the base of a mountain range.
For the next 7 hours of you EVA you meticulously collect rock samples. You are now a lunar geologist not a test pilot. You have been trained in geology and clearly understand what kind of rock samples you are looking for.
You return to the LM exhausted, but content in knowing you have done the best geology possible. You park the LRV east of the LM so the LRV camera can see the LM take off from the moon.
You and the LMP enter the LM, pressurize it and remove you helmet and gloves. You remove your PLSS back packs and set them on the LM floor near the exit hatch. These packs weigh 180 pound on earth, but on the moon they weight only 30 pounds. You also pile cameras and empty food containers near the hatch. You put your helmet and gloves back on and pressurize you space suits using the LM oxygen system through hoses. You open the depress valve and vent the cabin oxygen into space. You open the LM door and throw out the PLSS backpacks, and the other unnecessary items onto the lunar surface. All these items are useless now. There is no sense wasting the fuel to lift them into lunar orbit. Bye bye, spaceman junk.
You close the LM door, and pressurize the cabin one more time. You remove your helmets and gloves. You eat some food and drink some water and start to make preparation for LM take-off and lunar rendezvous. The Command Module is orbiting overhead, patiently waiting for your return.
You are now 171 hours into your adventure. You are tethered in your standing position at the LM control station. You are positioned to take-off from the moon. This is where you take off your geologist hat and put back on your test pilot hat.
You are amused at how many people it took to launch you from Earth. On the moon it's easy to press one button to launch yourself into lunar orbit.
Earlier you tested the assent stage rendezvous radar with the Command Module, as the mothership passed overhead. You will now test all four of your assent stage thrusters while still sitting on the lunar surface. After the test you winch when you notice you blew over a communication antenna. You should have planted the antenna further from the vehicle. The good news is all four thrusters checked out, and your assent stage is ready to fly.
You switch on the assent stage batteries and disconnect from the decent stage batteries. You now have 24 hours of power available on the assent stage batteries to rendezvous with the command module. This doesn’t concern you very much, because you should complete your rendezvous in the next two hours.
You receive “go for lift-off” from mission control. You press the “abort stage” button on the LM control panel. Pressing this button causes the assent and decent stages to separate, using pyrotechnics to sever four bolts that hold the two vehicles together. Explosive charges also drive guillotine blades through the wiring and plumbing that connected the two vehicles. The assent and decent stages are now completely disconnected.
The LMP presses a “proceed” button. The assent stage rocket motor is started and the LM lifts off from the surface of the moon. You hear the rocket motor firing through your space helmet. You realize the rocket combustion chamber is actually located inside the cabin, surrounded in a cylindrical cover that rose up from the assent stage floor. It is only two feet behind you.
The decent stage is now acting as a launch platform for the LM assent stage. It will remain forever on the moon. Bye bye, Lunar Module decent stage.
The assent stage goes straight up for 10 seconds and then pitches over 45 degrees to start gaining horizontal speed. There is no atmosphere on the moon, so the LM can gain horizontal velocity as soon as it lifts off. This fact allows for a very fuel efficient launch profile.
You are now looking straight down on the lunar surface as you quickly gain altitude. The view is just spectacular, but you glance away from the window to watch your instruments on the control panel. You are watching the velocity and altitude readings from the computers and comparing these numbers with charts from Earth. You are looking for any deviation that could indicate a problem.
The truth is you have actually done this rendezvous procedure tens of times in simulators back on Earth. You are absolutely amazed at how the actual numbers are matching the numbers you saw in the simulator. You quietly thank all those people back on Earth who worked so hard to make this voyage possible.
The assent stage rocket motor operates for seven minutes and shuts down. You computers tell you that you are in an elliptical orbit of 47 miles by 9.5 miles, exactly where you want to be. You are closing the distance between the LM assent stage and the CM, which is in a 60 mile circular orbit.
There is still one more short burn of the assent rocket motor necessary to catch the command module. This burn was called Terminal Phase Initiation (TPI). This burn will only last for 2.6 seconds, which is a good thing because you only have 6.5 seconds of fuel remaining. Yea the engineers cut the assent stage fuel margins real tight.
Forty minutes after take-off from the moon, you complete the TPI burn for 2.6 seconds. Your rendezvous radar locks on the command module radar. You can see the beacon light flashing on the command module from 40 miles away. This is a very good thing.
Your new orbit will intersect with the Command module, but because you are heading to a higher orbit, you will pass right on by. So the final maneuver for rendezvous is breaking.
When at a distance of 2 miles, you are in clear sight of the command module, and closing fast. You start to slow your craft down by firing your thrusters. Here is where your piloting skills are necessary. NASA gives you some guidelines about how to do this, but each commander had to use his own judgment. You are thankful for all the practice you had in the simulator. This is your best shot at lunar orbit rendezvous. If you miss, you could be lost in space forever.
After you successfully match the orbit of the command module you float next to it for a while. This is called station keeping. This operation allowed both vehicles to inspect each other for any damage. The CMP informs you, by radio, the LM looks "beat up" from take off acceleration. You then slowly approach the command module and dock with it, using the docking mechanism.
You unload film magazines, any valuable equipment and your boxes of lunar rocks from the LM to the CM. The CMP complains about how dirty both of you are and you agree. Your space suits are filthy, but there is nothing you can do. You will need you space suites for Earth re-entry. Oh well.
After all the valuables are removed from the LM assent stage, you close the hatch on the CM and jettison the LM assent stage. The LM assent stage will impact the moon and send back to Earth data collected by the seismometers that are on the lunar surface. Bye bye, Lunar Module assent stage.
You are exhausted, but relieved at your success. All the remains to be done is to leave lunar orbit and re-enter the Earths atmosphere.
You are now 294 hours into your adventure. Earth looms very large in your command module window. It is growing larger by the minute, because you are now traveling at 24,600 miles per hour. You are about one hour before re-entering the Earths’ atmosphere and there are lots of things to do. Most importantly, you must secure anything loose in the command module cabin. Cameras, rock boxes and other things have to be secured. The g-forces of re-entry could exceed 7 g’s, so anything loose could cause a lot of damage.
Fifty minutes before re-entry you press a button that activates explosive charges to open valves connecting the Reaction Control system (RCS) thrusters to their fuel tanks. The reaction control system is used to aim and direct the command module during re-entry. This system will fly the command module to a target in the ocean not far from Hawaii. Without the RCS system the command module could not safely land on Earth.
Twenty five minutes before re-entry you and your crew begin to prepare the service module for jettison. You connect the command module to its internal batteries. You then disconnect the command module from the service module electrical fuel cells. There are only two hours of electrical energy in the command module internal batteries. You are not concerned by this because in thirty eight minutes you plan to be floating in the ocean near Hawaii. You then press a button to activate explosive charges that disconnect the CM from the service module. Bye bye, service module.
The CMP turns the command module around so its blunt heat shield is facing the direction of travel, which is toward the Earth.
Thirteen minutes before landing, the computer control system detects a deceleration of .05g. You are at about 400,000 feet and this begins the Earth re-entry sequence. You are now traveling at 25,000 miles/hour. In the next thirteen minutes you will travel 1,360 miles across the Earth. The ablative heat shield will heat to 3,000 degrees Celsius, which is as hot as the visible surface of the sun. You and your crew will be subjected to 7.19 g’s at the peak of your deceleration. The temperature inside the command module will only rise by one degree. How remarkable is that?
The crew had little to do but look out the windows. Your spacecraft is under computer control. There is a manual control mode, but you prefer the computer to land the vehicle safely in automatic. Hot plasma envelopes your vehicle as it plows into the atmosphere at high speed. The color out the window starts as a dull red glow, and eventually becomes a white hot glow. The white hot "Air glow" is so intense you can't look directly at it.
The RCS system rotates you craft around 180 degrees. One second you are in the "feet up" position, and another second you are in the "feet down". This rotation actually increases or decreases your altitude, which aims your vehicle to land in an exact location.
NASA scientist determined 7 g's as safe for the astronauts returning from the moon. When you are in the "feet down" position, your craft is plowing deeper into the atmosphere causing the vehicle to rapidly decelerate. The g-forces on the astronauts body increase to 7 g's.
When the computer measures 7 g's, the RCS system would rotate the vehicle 180 degrees and the astronauts would be "feet up". The vehicle would gain altitude, and the g-force would reduce to 4 g's for a time.
All the while the CM computer is calculating and steering a course to your landing site. If it calculates your vehicle is going to miss your destination too long, the RCS system rotates the CM 180 degrees to the "feet down" position. You again plow deeper into the atmosphere and rapidly decelerate. The g-force go to back up to 7 g's.
This cycle of high g-forces and lower g-forces continued many times. You may actually skip back into outer space when you are in the "feet up" position, but your velocity is so low you fall back toward Earth.
Eventually you have lost so much altitude and velocity you are falling straight down. You're within a few miles of the Hawaiian sea. You are truly amazed that this system works so well.
At an altitude of 11 miles the cabin pressure relief valve is set for entry mode. When the air pressure outside the command module is greater the the pressure inside the vehicle, the valve will open and allow some outside air to enter the cabin.
At six miles high the apex cover on top of the command module is jettisoned, and two drogue chutes are deployed that stabilize the craft. Removing the apex cover exposes the three main chutes for deployment.
At 9000 feet of altitude a barometric switch operates to fire mortars that deploy three pilot chutes, which then pull out the three main chutes. These three chutes are each 25 yards across and slow the command module decent to a safe speed.
The RCS thruster fuel tanks still contain hydrazine rocket fuel. The fuel tanks must be emptied for the safety of the recovery crews. You close the cabin pressure relief valve to prevent the rocket fuel from entering the cabin. You fire the thrusters until the fuel tanks are empty. You purge the empty tanks with helium gas to make the system safe. You then reopen the cabin pressure relief valve and equalize the crafts cabin with the air pressure outside.
At 750 feet you once again close the cabin pressure relief valve to prevent sea water from entering the cabin. When the command module hits the ocean it may partially submerge or even land upside down. Your mission ends with a perfect splashdown is a smooth and nearly wave free sea.
What a great conclusion to an adventure that lasted over 12 days. Congratulations you’re home on planet Earth!
These books were useful in developing this web site.
W.D. Woods, How Apollo Flew to the Moon, Springer Praxis books
David M. Harland, The First Men on the Moon, Springer Praxis books
Thomas J. Kelly, Moon Lander How We Developed the Apollo Lunar Module, Smithsonian books
Robert Godwin, Apollo 11 the NASA Mission Reports Volume 1, Apogee books
Robert Godwin, Apollo 11 the NASA Mission Reports Volume 2, Apogee books
Robert Godwin, Apollo 14 the NASA Mission Reports, Apogee books
Robert Godwin, Apollo 15 the NASA Mission Reports, Apogee books
Robert Godwin, Apollo 16 the NASA Mission Reports, Apogee books
Robert Godwin, Apollo 17 the NASA Mission Reports, Apogee books
This web site will get you deep into the weeds on the subject of Project Apollo.
I would like to give special thanks to Professor Kimberly Moscardelli, of Henry Ford College. Her positive attitude is contagious and has inspired me to do my very best.