Flown on Apollo 13, LM Contingency Checklist, pp 24 and 25. A single sheet printed recto and verso. NASA/MSC, January 6, 1970, revised February 26, 1970. 8 x 5 1/2 inches. Extensive annotations made during the mission in red ink by James Lovell and in black ink by Fred Haise.All was proceeding as planned for the Apollo 13 mission until Mission Control asked the crew start a standard procedure to stir their fuel cell oxygen tanks for the first time during the mission. Because of damaged wiring, an electrical short circuit within oxygen tank number 2 caused the tank to overheat. The resulting increasing pressure reached a point where the tank to exploded. Within seconds the crew observed a series of caution and warning lights on their Command Module control panel and radioed to Houston, "We've had a problem here." The crew and Mission Control most of the next hour of flight trouble shooting the problems with the Command Modules fuel cells. These fuel cells used oxygen from the tank that exploded which caused damage to associated plumbing and electrical connections. The explosion also caused damage to oxygen tank number 1. Pressure and power from the fuel cells were rapidly dropping, forcing Mission Control to tell the crew to close the reactant valves of the fuel cell systems. To close these values was to do so permanently, and when the crew did this they knew that that the lunar landing was lost for this mission.The Command Module (CM) was then rapidly running out of oxygen and battery power. The crew needed to save important navigational data stored in the CM computer and transfer that data to the LM during the initial power up of that vehicle. The crew reviewed all LM activation steps to rapidly power-up the LM, including the steps of this "30 Minute Activation" sheet.Their Fra Mauro landing site's location on the moon required the astronauts to fly Apollo 13 to a lunar orbit that would not automatically return them to earth if they could not slow down their vehicles for lunar orbit insertion. Lovell and Lunar Module Pilot Fred Haise were able to put the their LM and crippled CM back onto a "free-return trajectory" at about 61 hours and 30 minutes into the flight, some 5 1/2 hours after the explosion. This ensured they would arrive back to the earth but not that they would have enough power and oxygen to survive the trip.Another LM engine burn some 2 hours after they passed around the moon enabled them to arrive at the earth with sufficient power and oxygen to survive the flight. However, to precisely enter the Earth's atmosphere at the time, speed, and angle required to live through the atmospheric heating effects of re-entry, required a course correction NASA call MCC-5 or Mid Course Correction number 5.An included letter of provenance by FRED HAISE reads: "Accompanying this letter is a sheet number 24 and 25 from the Apollo 13 LM-7 Contingency Checklist carried and used on the flight of Apollo 13 during April 11 to 17, 1970. Our flight was scheduled to be the third manned lunar landing mission but had to be aborted after a Service Module oxygen tank explosion. During this emergency, power conservation was paramount in order for us to survive the amount of time required to return to the earth. Commander Jim Lovell and I used this sheet to configure the Lunar Module 'Aquarius' prior to the MCC-5 or Mid Course Correction burn number 5 during our return to earth. MCC-5 occurred at 105 hours and 18 minutes into the flight. It was a 15 second burn of the LM's descent engine done to refine our entry corridor flight path angle as we entered the Earth's atmosphere prior to landing.The side numbered 24 has the initial steps for the LM '30-MIN ACTIVATION.' At about 99 hours and 55 minutes into the flight, Mission Control radioed recommended changes to the activation for the MCC-5 burn. Jim Lovell labeled the top of this page with 'MIDCOURSE 105.00 AGS,' meaning we would use the LM Abort Guidance Section for the burn. Jim then marked through the three blocks of 'IVT TO LM' or IntraVehicular (crew movement) to the LM procedures and wrote 'OMIT' in red three times. We were instructed to begin with step 4 and I added the 'VERIFY AGS STATUS SW ? OFF' instruction. Just to the right, Jim wrote: 'time 15 min' meaning start with this step 15 minutes before the MCC-5. Under 'EPS (Electrical Power Subsystem) ACTIVATION,' Jim recorded that we were to 'Do' step 1, 'OMIT' step 2 except for the second to last function where Jim wrote 'Do' again. He marked through unwanted steps in red. After the flight I wrote and signed this side in blue ink with: 'In flight notes in red by Jim Lovell. 'Verify AGS' note by Fred Haise. Carried on and used during the flight of Apollo 13. Fred Haise, Apollo 13 LMP.'The side number 25 has the continuing steps to this activation. Jim wrote 'OMIT' and drew a red line through step 3 and another line through the last procedure of step 4. Under the 'PRIMARY GLYCOL LOOP ACT' steps, Jim wrote 'Crew Option' for the first line and drew a line through the remaining part of step 1 and a line through step 2. He recorded that we 'Do' step 3. After the flight, I wrote and signed this side in blue ink with: 'In flight notes by Jim Lovell ? Carried and used during the flight of Apollo 13. Fred Haise, Apollo 13 LMP.'This sheet has been in my personal space collection since 1970. It is an extremely significant artifact that records some of the most important events and procedures James Lovell, Jack Swigert, and I performed in order to safely return to earth."Additionally SIGNED AND INSCRIBED on the side numbered 25 with: "James Lovell, Apollo 13 CDR."