Apollo 1201 and 1202 alarms for windows

Apollo 11s momentous landing came down to one tough call. The problem was a procedure checklist for lunar descent which neglected to set docking radar to off. No one could celebrate until the astronauts were safely. Jack garman, of apollo 11 1201 alarm fame, has died. Garman recognized the unexpected 1201 and 1202 alarms. As the vehicle approached the target, one of the astronauts, buzz aldrin i believe, announced that the onboard computer just displayed a 1202 alarm. This video shows that the 1202 alarm which happened in the descent of apollo 11 had nothing accidental, but had been intentionally provoked, for the conditions for it to happen had been. Margaret hamilton takes software engineering to the moon.

Neil armstrong, the 1201 alarm, and greatness personified. Jack garman, whose grasp of the apollo 11 guidance computer saved the moon landing from a lastminute abort, died sept. When the apollo guidance computer became overwhelmed during apollo 11s historic moon landing, it sounded the 1202 alarm and required the. This cheat sheet created by nasa flight controllers jack garman and steve bales show alarm codes for the apollo lunar. Even the cause of the 1201 and 1202 program alarms during apollo 11s landing is accurately documented mismatched phase angles in spacecraft and radar power supplies, not computer errors. An unsung hero of the decision not to abort the landing is richard koos, a nasa simulation supervisor who, on the afternoon of july 5, 11 days before the launch of apollo. Do the famous 1201 and 1202 error codes make an appearance. He and flight director gene kranz were dressed down for it by koos, who put the team through four more hours of training the next day specifically on program alarms. On apollo 11, each time a 1201 or 1202 alarm appeared, the computer rebooted, restarted the important stuff, like steering the descent engine and running the dsky to let the crew know what was going on. It was the extra processing time from the docking radar routine which wasted the computers time and caused the 1201 and 1202 alarms. As a young specialist on duty during the final descent stage on 20 july 1969 he dealt with a series of computer alarms. On apollo 11, who made the decision to preload the lems ascent program and the lunar rendezvous program, which presumably led to the 1202 and 1201 stack overflow alarms. Unable to figure out what the 1201 was, bales aborted that simulated landing. No one could celebrate until the astronauts were safely back.

On apollo 11, each time a 1201 or 1202 alarm appeared, the computer rebooted, restarted the important stuff, like steering the descent engine and running the dsky to let the crew know what was going on, but did not restart all the erroneouslyscheduled rendezvous radar jobs. And since those tasks hadnt exited by the time they were expected to, when the executive attempted to kick off new tasks, it found that no core sets or vac areas were available, and sounded those program alarms. We waited with anticipation, pride and apprehensiveness as the lem began its descent toward the lunar surface. Garman remembered the 1201 and 1202 alarms occurring during one of the hundreds of simulations the team performed in preparation of the apollo 11 mission, and knew it would be ok to. Project apollos digital brain softwares giant leap. There are even more materials to digitise and share for the later apollo missions and just a small amount helps. Thats a somewhat similar case of the 1202, namely that the reboot temporarily solves the problem of letting the computer proceed, but it didnt solve the root cause of the faulty radar unit aspects. The 1201 alarm was a signal triggered by the apollo. Margaret hamilton coding to the moon a computer of one. The two alarms that apollo 11 encountered during descent were 1201 and 1202. Example of the apollo 11 lunar module display and keyboard dsky like what lit up with 1201 1202 alarms on apollo 11. The nasa guys in the mocr knew because mit had extensively tested the restart capability that the mission could go forward. During the landing sequence of apollo 11, 1201 and 1202 program alarms lit up the cockpit several times. The agc reboots with a program code 1201 and 1202 executive overflow during landing phase if the rendezvous radar switch it set to auto as suggested in procedure book and the.

This is where the 1201 and 1202 program alarms come in. But it did it quickly, and no guidance or navigation data was lost. Apollo 11 had both the radar altimeter landing radar and the rendezvous radar used to guide them into the vicinity of the csm running during landing. This triggered 1201 and 1202 alarms executive overflow, which caused the computer to reboot. Apollo 11 go for landing and program alarm 1201 eduardo garciallama. The 1202 program alarm is featured is just about every retelling and dramatization of apollo 11s lunar landing.

Jack garman, nasa engineer who saved apollo 11 from. That day the normal mission sequences were interrupted by priority displays of 1201 and 1202 alarms warning there was an emergency of executive overflow, giving the astronauts a gono. Here then are some insightful apollo 11 lessons for ai developers, automakers. My first user had a program alarm 1202 during a descent phase. Each time, the software restart flushed the executive queue but could not shed load. The codes meant that the computer had so much to do, it couldnt get it all done in real time, and so it had to postpone some of its tasks. Garman recognized the unexpected 1201 and 1202 alarms that could have led to flight controllers aborting the mission. The apollo guidance computer agc is a digital computer produced for the apollo program that was installed on board each apollo command module cm and apollo lunar module lm. Kranzs decision whether or not to abort the mission was based on a simulation right before. There were three 1201 and 1202 alarms within 40 seconds. Recognition of apollo 11 program alarms collectspace. Less than minute later, there was another 1202 alarm, followed by three more a 1201 and two 1202 alarms in under 40 seconds. Despite the exhaustive training, simulations and procedures governing apollo 11, the 1202 alarm program was not familiar to the flight director or the other engineers in the room.

For a replay of the 1202 event, view the linked video at 7. This film was shot in the mission operations control room during the apollo 11 powered descent to the lunar surface. What is a 1201 error as referenced in the movie apollo. The 1202 and 1201 alarms were unsettling, and the team doubted the computers health. On apollo 11, who made the decision to preload the lems. The computer was overloaded with data and ran out of memory so the program gave the famous 1201 alarm. What caused the 1202 alarm of apollo 11, and how were the. The historic 1969 mission where neil armstrong and buzz aldrin became the first men to walk on the moon. Armstrongs tense voice came over the radio, program alarm, its a 1202 give us a reading on the 1202 program alarm. When the 1202 and 1201 alarms occurred during the actual landing, garman, bales. Apollo 11s 1202 alarms not long after the lunar module got into its 69 mile by 50,000 foot orbit in preparation for landing, the crew.

John royer jack garman september 11, 1944 september 20, 2016 was a computer engineer, former senior nasa executive and noted key figure of the apollo 11 lunar landing. Margaret hamilton takes software engineering to the moon and beyond. This alarm is a bit more severe as it indicates that the imu is not responding. In this article, the author states that thanks to a previous simulation, apollo 11 capcom charlie duke recognized the 1202 and 1201 program alarms. The dsky displays the value 210, which is a different alarm code than the 1202 and 1201 that aldrin saw. Apollo 11 transcript starting at 04 06 35 51 on spacelog. Build your own apollo 11 landing computer universe today. With all of this additional work, the agc didnt have enough time to finish its low priority tasks. Asked in mobile phones, nokia phones security code nokia model 1202 2. As the author of the originally 1974 bis spaceflight article apollo on board computers which was later taken up by the nasa history for the apollo15 flight journal web site i get asked quite regularly by readers what were the 1201 1202 alarms. W hen apollo 11 was rocketing to the lunar surface, the onboard computer began to issue 1201 and 1202 program alarms. The software that saved apollo 11 softwares giant leap. How did the apollo flight computers get men to the moon and back. If youve enjoyed the 1201 alarm project, free audio and images, please help us to keep going.