THE MISSION

Countdown for the Apollo Uprated Saturn (AS-202) vehicle at Launch Complex 34 will begin about 25-1/2 hours before liftoff. During the early chases of the count final checks of the spacecraft, ordinance arming and mechanical work on the launch vehicle will be accomplished.

Liquid oxygen loading to both stages of the Saturn launch vehicle will begin six hours before scheduled liftoff. Liquid hydrogen loading to the second stage will begin four hours before launch. Hatches of the spacecraft will be sealed 45 minutes before liftoff, and 15 minutes later the Apollo access swing arm on the umbilical tower will be retracted.

Terminal phase of the countdown will begin 30 minutes before launch. At 2 minutes 43 seconds before liftoff the countdown will go on automatic sequence.

The vehicle will be held on the pad for about three seconds after the eight first-stage engines ignite to assure stable combustion. It will lift off the pad on an azimuth of 100 degrees East of North, roll to 105 degrees and begin to pitch or tilt along the flight path, a southeasterly direction from Cape Kennedy.

The first stage burns for 2 minutes 23.7 seconds and the stage is separated. The booster propels the vehicle to a 35- mile altitude and 35 miles down range. The stage impacts about 270 miles downrange near Antigua.

Two recoverable movie cameras mounted on the forward end of the first stage will record separation and ignition of the second stage (See Cameras, Page 23).

A few seconds after the second stage J-2 engine ignites, the spacecraft launch escape system is jettisoned. The engine burns for about 7 minutes 23 seconds producing thrust to carry the vehicle to a 135-mile altitude some 969 miles from the launch site.

About 10 seconds after second stage cutoff the spacecraft separates from the stage and Saturn instrument unit. A television camera mounted in the instrument unit will record movement of the spacecraft lunar module adapter panels as they fold back to free the spacecraft. The adapter will house the lunar module on later Earth orbital flights and lunar landing missions. Signals from the camera will be monitored and recorded at the Antigua tracking station (See Cameras, Page 23 ).

The pressure test of the second stage common bulkhead will begin 90 seconds after spacecraft separation. The liquid oxygen tank vent valve will be opened and the liquid hydrogen tank vent valve will be closed. This will cause the pressure differential across the bulkhead to increase. The amount of increase will depend on the amount of liquid oxygen remaining in the tank. Maximum pressure is expected to be reached as the stage reenters the atmosphere over the Atlantic Ocean.

A few seconds after spacecraft separation the 21,500 pound thrust service module propulsion engine will be fired for the first time. This burn of three minutes 35 seconds will boost the spacecraft to its peak altitude of 706 miles over South Africa about 41 minutes after liftoff.

The second service propulsion engine burn, of one minute 28 seconds, will occur approximately 25 minutes later over the Indian Ocean near the Western tip of Australia. About 10 seconds later, the third and fourth burns, each of three seconds duration, take place. These are to test the rapid restart capabilities of the engine.

The spacecraft guidance and control system will orient the spacecraft for separation of the command and service modules about two minutes after the fourth service propulsion burn. The 100-pound thrust service module reaction control engines are fired to separate it from the command module.

A few seconds after separation the command module will be oriented for the long shallow reentry. From an altitude of 400,000 feet it will descend to 218,000 feet at a speed of more than 19,000 miles per hour. At this time the guidance and navigation system will initiate the reaction control system to modulate the lift vector and the spacecraft will skip back to an altitude of about 264,400 feet.

From this altitude the final phase of reentry begins at velocity about 16,000 miles per hour.

The apex cover of the spacecraft will be jettisoned to deploy the two 13-foot diameter drogue parachutes at 23,850 feet altitude. me three 83-foot diameter main parachutes are deployed at 10,350 feet. Splashdown is expected one hour, 32 minutes, 54 seconds after liftoff.

The predicted landing point for the mission is at 17 degrees 9 minutes N latitude and 171 degrees 87 minutes E longitude, located in the downrange portion of the terminal landing footprint. The terminal landing "footprint" is an area 3,500 nautical miles long, varying between 200 and 300 nautical miles in width cutting between the Caroline and Marshall Islands with impact point 300 miles southeast of Wake Island in the North Central Pacific.

The aircraft carrier, USS Hornet, two destroyers and seven C-130 aircraft comprise the Department of Defense recovery force in the area. The USS Hornet will be at the predicted impact area.

Should the spacecraft's guidance system fail, a ballistic reentry will be achieved and landing will be in the uprange portion of the long footprint. This impact point is approximately 1, 000 miles uprange in the vicinity of the Caroline Islands, north of New Guinea.

After recovery the Command Module will be taken to Downey, California, for post-flight analysis by NASA and North American Aviation engineers.