Ok, the initial version of the Launch Window Processor is almost ready. Here is the workflow to use it, which may still change a bit, also based on feedback. I'm not very talented in making MFDs user friendly. :lol:

New button in the main menu:

There are several inputs screens for the LWP, although most of the values will not have to be changed every time you use the LWP:

-TGT is the target vehicle, whose state vector is used as an input to the LWP.

-LS can be used to input a specific launch pad (39A or 39B currently), so that the coordinates are automatically loaded. Default is LC-39A.

-LAT can be used to overwrite the launchpad latitude (if you want to launch to the HST you might have to bias the latitude southwards in order to get the LWP to calculate a solution).

-LNG to overwrite the launchpad longitude.

-YS is the maximum yaw steering the Shuttle can do for the ascent to orbit. Not really relevant for SSU right now and it should probably always stay 14°

-PFA is the powered flight arc from launch to insertion. All the values on the right side of this screen are used in an analytical calculation of the Shuttle ascent. This is all the LWP can do, so updated values would need to be supplied for ascents that are very different from a usual one. But it's not super critical to have these values exactly right.

-PFT is the powered flight time from liftoff to insertion. Not MECO I guess, more the decay of all thrust or so.

-RAD is the insertion radius in feet. Might be a bit of an awkward unit to use for SSU, but that's what the FDO Handbook showed in a screenshot of the LWP inputs.

-VEL is the insertion velocity. This and FPA below will need to be adjusted for the specific mission, because it's very different from e.g. a mission to the ISS vs. to the HST.

-FPA is the flight path angle at insertion. All of the values on this page are usual values for a mission to the ISS, I think.

The next page has some rarely changed values. By the way, if you didn't know, pressing MNU will show descriptions of all buttons:

-DTE is the delta time from MECO to ET separation. Probably always 12 seconds.

-DVE is the DV vector of the ET separation maneuver. the DVX component should be either 0 ft/s (no +X translation maneuver or ET photo pitch maneuver) or 5 ft/s (to account for the +X translation maneuver). For DVZ I have seen 4 or 5 ft/s, not sure which value is closer to accurate. This will be the translation maneuver that is done automatically to get away from the ET. +5 ft/s if the attitude is heads down or -5 ft/s if the attitude is heads up.

-DTM is the delta time from MECO to the MPS dump; just like the ET sep maneuver this assumes an impulsive burn. The delta time is probably fairly constant.

-DVM is the DV of the MPS dump. The FDO Console Handbook has numbers that are averages from flight data:

heads down: +9.2, -2.6, -4.2

heads up: +9.7 +0.2 -1.0

-DELNO is the descending node bias that is used to account for differential nodal precession. This should always be 0 with non-spherical gravity disabled. There currently is no way yet to let the LWP calculate the value automatically, so it has to be done by trial and error. Calculate a LWP solution, then run the OMP with the state vector from LWP output and check the size of the NPC maneuver. A very rough estimate for this is phase angle at liftoff divided by 500. So for a phase angle of 300° it will be roughly 0.6° DELNO. This only applies to a FD3 rendezvous, for FD4 it will be more, for FD2 it will be less.

-OPT is the optimal, zero yaw steering delta time from the in-plane time. Launching at exactly the time when the target vehicles orbit is over the launchpad is not optimal because by the time you have left the atmosphere, a few minutes later, the orbit is already far away from the launchpad. This is an empirical derived number depending on time it takes to ascent to orbit etc. The FDO Handbook has -5:40, but I've tested it a couple times and for SSU the best value is -5:23. This will only be exactly for 51.6° inclination and a specific Shuttle weight and insertion conditions but it should be quite close in all cases.

-DTO is the delta time for the opening of the launch window. Launch window to the ISS is usually 10 minutes long, so DTO and DTC are -5 minutes and + 5 minutes. SSU can't do any yaw steering and this is only really used for the calculation of the phase angle right now. Just for information purposes.

-DTC is the delta time of the launch window closing.

-PHA and WRA are two rather unintuitive flags used by the LWP and currently it will only be used in the phase angle calculation. For example, this will decide if a phase angle is 30° or 390°. Here is the numbers that are used for this, as per the FDO Handbook:

And here the output page:

The only button is CLC, to perform the calculation. This will populate the numbers on this page and also save a post MPS dump state vector for the OMP to use. Additionally it will overwrite the current launch time in the MFD. On the executive page you can see that the chaser vehicle is now showing "LWP Output":

The only numbers that are currently relevant for SSU are the optimum launch time and the inclination (IMECO) that are displayed on the LWP output page. I guess you will have to write down the numbers and then adjust the inclination in the mission file and the LaunchMJD in the scenario file. I could also add an export button so that all the insertion parameters and the launch MJD are saved in a file where you can copy them over to the mission and scenario files.

So this is how the LWP is going to work initially. There are many features which are currently not implemented or don't have a button yet: insertion at a specific phase angle instead of in-plane, calculating the descending node angle and with that an orbital plane vector for the Shuttle to target. And ascending/descending node launches, which would be relevant for a launch at VAFB. Any initial feedback on the user interface part?