I'm finalizing my plans for ignition settings, incorporating feedback from the class 3 analysis report and my build weights and flight results. The mass and dimensions came out pretty close to the initial predictions, so the plots on the first page of this thread are still valid. It turns out that the horizontal distance requirement for the FAA agreement is for the 3-sigma dispersion to be less than 80,000 feet radius. That's 15 miles, much farther than I would want the rocket to land because it would put a lot of unfavorable terrain in play.
5 miles in any direction will still be on the playa, and 10 mile landing radius will have a good chance of landing on the playa or in areas where retrieval wouldn't be too extreme. If I allow ignition at a sustainer angle of 12 degrees, that would put apogee about 10 miles away. But since the air is so thin if I get a good boost, the apogee deployment wouldn't slow down the apogee deployment for a while, so I should back off of that a bit and aim for a targeted ignition angle of 10 degrees. This is accomplished with the angle > future angle threshold setting, which is the angle estimated after a 3 second ignition delay.
There are four categories of initial flight angle with this ignition setting strategy
Category 1: Near-vertical boost. In this case, the angle is less than 10 degrees at sustainer ignition, and the trigger is altitude that corresponds to the optimal ignition altitude for a near-vertical flight. This is 29kft if I don't get any significant sustainer aeroheating damage. But if there is enough damage to correspond to turbulent flow for the whole flight, then 27kft would be the optimal ignition altitude. This is what I will pick for this case. This case will be covered by the primary set of deployment logic for channel 3 for my sustainer.
Category 2: Boost straight enough to want to delay until the target tilt at ignition. This will be triggered by the future angle exceeding 10 degrees. This will be the driver for the secondary logic for channel 3.
Category 3: Boost is pretty angled, so I want to fire the sustainer as soon as it's slow enough. The secondary ignition logic will also drive this case. In this case the ignition angle will be higher than the target angle, but less than the maximum safe angle. The dispersion analysis calculated that there was no initial angle that would violate the FAA horizontal limits, through 20 degrees, so that makes this category viable. Based on the simulated horizontal distance, I will set the maximum tilt angle at 16 degrees for this case, knowing that with a 2 second ignition delay, it could be 18 degrees. If I simulate that case, it takes a 10 degree initial angle to cause this, and the altitude two seconds before 18 degree pitch angle is right at 19,000 feet. This flight sims to 103 kft and the downrange distance at apogee is 50,000 feet (9.5 miles) This is the maximum initial angle coming out of the launch tower that I'll tolerate for a sustainer ignition. Thus I'll set the maximum tilt angle of 16 degrees, minimum altitude of 19,000 feet for the secondary logic case.
Category 4: The initial angle is so poor that I don't want to ignite the sustainer at all. If the rocket is tilted > 16 degrees and getting worse as it passes through 19,000 feet, it will be a 2-stage + dart flight, but I'll likely get the stages back to fly another day.
Next I'll figure out what I want for the limits of the 2nd stage ignition, but dinner comes first.