Let me preface by saying this is an excellent project. It's unbelievable what you guys are offering for free. Thank you.
As someone else stated, I am going down the AGS rabbit hole now. I like to think I have thoroughly studied the physics, systems and manuals so that I am not just a monkey flipping switches. Attached is my Apollo 16 PDI scenario. The cabin is nice and comfy, antennae are tuned, and a PGNS guided descent, landing and/or descent abort go flawlessly. However, the abort insertion for an AGS descent abort is always high at apolune (I did read the thread about APS cant). 315 and subsequent 337 readout place it at 63NM (which would be correct and is what the AGS believes) but it's actually about 85 NM. So, using the wonderful Rosetta stone of the supplied Apollo 17 PDI, I noticed one important discrepancy. During PDI all the way down to about 2000 ft AGL, the PGNS, radar, and AGS ALT agree within +/- 2000 feet. The RATE of descent all agree within within about 5 to 10 fps. An easy 223 update of +00020 makes an AGS descent abort work perfectly. Unfortunately, in my scenario, AGS and PNGS ALT and ALT rate agree very closely until about 5 mins in. Shortly after V57E and about 5:10, the AGS and PGNS rate of descent diverge sharply. By the time 15,000 feet is reached, the PGNS and radar agree that ROD is about 90 fps, but flipping the switch to AGS it thinks ALT is zero and the ROD is 220fps! So this must be the culprit, something is wrong or not setup correctly by me in that accelerometer for the strapped down gyro. Either a scaler isn't right or I did something wrong. Obviously this disagree negatively impacts ascent trajectory and orbit since the climb rate that the AGS believes and the actual diverge as well. Here is the scenario. Thanks.
Edit. Those numbers were a little off. They are about 5000 ft AGL. At 15,000 ft AGL , PGNS ROD is about 220fps and AGS ROD is 330 or 340 fps.
As someone else stated, I am going down the AGS rabbit hole now. I like to think I have thoroughly studied the physics, systems and manuals so that I am not just a monkey flipping switches. Attached is my Apollo 16 PDI scenario. The cabin is nice and comfy, antennae are tuned, and a PGNS guided descent, landing and/or descent abort go flawlessly. However, the abort insertion for an AGS descent abort is always high at apolune (I did read the thread about APS cant). 315 and subsequent 337 readout place it at 63NM (which would be correct and is what the AGS believes) but it's actually about 85 NM. So, using the wonderful Rosetta stone of the supplied Apollo 17 PDI, I noticed one important discrepancy. During PDI all the way down to about 2000 ft AGL, the PGNS, radar, and AGS ALT agree within +/- 2000 feet. The RATE of descent all agree within within about 5 to 10 fps. An easy 223 update of +00020 makes an AGS descent abort work perfectly. Unfortunately, in my scenario, AGS and PNGS ALT and ALT rate agree very closely until about 5 mins in. Shortly after V57E and about 5:10, the AGS and PGNS rate of descent diverge sharply. By the time 15,000 feet is reached, the PGNS and radar agree that ROD is about 90 fps, but flipping the switch to AGS it thinks ALT is zero and the ROD is 220fps! So this must be the culprit, something is wrong or not setup correctly by me in that accelerometer for the strapped down gyro. Either a scaler isn't right or I did something wrong. Obviously this disagree negatively impacts ascent trajectory and orbit since the climb rate that the AGS believes and the actual diverge as well. Here is the scenario. Thanks.
Edit. Those numbers were a little off. They are about 5000 ft AGL. At 15,000 ft AGL , PGNS ROD is about 220fps and AGS ROD is 330 or 340 fps.
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