March 25, 2023: I've gotten some time with the WT AAU1 Longitude effort and felt like this modification project still has merit, specifically with respect to aircraft handling and performance. So I've simplified the package a bit, returning many values to the new default values, but retained the performance, handling, and engine peformance that were part of the prior versions of the modification project. I hope you enjoy these changes. Please comment any issues you find with handling and aircraft performance in the comments below or on my MSFS official forum page. Longitude Mod Forum Page

IMPORTANT, READ FIRST
Installation / Mod Package Notes: 

• You must have the deluxe premium edition of MSFS 2020 with the stock Longitude model to use this Mod. This mod is not a stand-alone aircraft. If you install without, you will see game crashes.
• After each sim update, if not automatically done for you and if you haven't done so already, you must also update the premium and deluxe premium content from the in-game content manager or you will not be able to use the Longitude (and other aircraft) properly.
• This mod doesn't address ANY major avionics modifications to the PFD or MFDs or general cockpit functionality. Unless you can clearly demonstrate otherwise, any bugs or issues with the cockpit functionality are not related to this mod. Please DO NOT inquire about avionics or instruments faults or bugs that you find with the game's default avionics - I can't help you. These are not the subject of this mod and I am not affiliated with Working Title.
• You must have Modern flight model enabled to use this mod. It will not work properly with Legacy flight model settings.
• To confirm correct installation, when in the livery selection menu for the Longitude in MSFS2020, the default Asobo Longitude livery will display the following in the variant area "FDE Fix VX.XX" depending on the install version you choose. This will help you quickly identify whether installation of the package was successful and identify package version - this version information will only show up under the default Asobo livery listing and not other liveries, however the performance modifications will be applied to all other stock liveries or third party liveries you have installed.
• The mod does not work with all third party liveries. Some third party liveries are old/out of date and never did or no longer follow proper file structure / installation guidelines and are not compatible. As a result you may see instability or crashes when you do attempt to use these liveries. 
• If your install doesn't work initially, before posting here or on the forum, please close the sim and remove the mod from the community folder. Start the sim and completely reinstall your default Longitude from the Content Manager under your Profile area to ensure you have the latest version. Verify the stock / default Longitude is present and works correctly. Close the sim. Re-download the package here and then re-install the mod as directed (downloads from this site can become corrupted, so that can be a cause of problems with the mod). Restart the sim and verify installation. If this doesn't work, PM me. 

Asobo Cessna Citation Model 700 Longitude Performance and Flight Dynamics Modifications Project Version 2.02

Please check out the chatter and follow the progress of this project on the offical MSFS 2020 Forum:
Longitude mod forum page

Updated for compatibility with AAU1 Working Title package and SU12

-Revised thrust mapping table to eliminate reverser sounds and thrust drag when engines idled at high a/c speeds.
-Reduction in flaps drag for more realistic performance esp. at full flaps.
-Increased available thrust at lower engine rpm settings at lower speeds
-Increased flaps lift to further match Vref and Vapp speeds.
-Reduced oscillations around roll axis on instrument/localizer approaches.

Please see version notes in the included install_readme file for a list of all changes made since project inception and a list of open items / known issues.

Installation:

• Download the .zip file and extract to desktop or other location of choice.
• Install in your Community folder
• Start the sim and enjoy the modded Longitude.
• Please read and follow the installation instructions in the included Install_ReadmeVX.XX.txt file carefully.

The Cessna Citation Model 700 Longitude Performance and Flight Dynamics Modifications Project:

Back in 2021, after reading user comments on the forums regarding the Cessna Citation Longitude model from Asobo concerning major autopilot problems, inaccurate weights, fuel load, fuel consumption, handling, etc... and due to my own poor experience and frustration with Asobo's starting efforts, I started work on revising a wide variety of parameters in the configuration files. I'm not a Longitude pilot, so my modifications are based on comments on forum topics from those who fly the type, and generous contributions of real world C700 aircraft performance charts, flight manuals, and checklists from fellow flight-sim enthusiasts who also fly IRL for a living. Input from type-rated pilots with knowledge of the aircraft handling and envelope will always be greatly valued. 

As of 2023 Working Title has now taken over development of the stock Longitude. My latest efforts are more focused on handling and performance characteristics and I make no attempts to modify or improve on their well implemented avionics suite upgrades to the model as part of AAU1. 

I have modified a great many variables and parameters in the available configuration files. I would greatly appreciate feedback on handling, control sensitivies, or other performance related parameters from knowledgable sources so I can continue to improve and update these modifications. If I missed something or you find a performance "glitch" please let me know.

NOTE: My adjustments are generally focused on performance and handling. Any issues with avionics or cockpit system are not the subject of this modification. 

I have modified a many variables and parameters in the available configuration files. I would greatly appreciate feedback on handling, control sensitivies, or other performance related parameters from knowledgable sources so I can continue to improve and update these modifications. If I missed something or you find a performance "glitch" please let me know.

Contribution credit and acknowledgements can be found in the Install_ReadmeVX.XX file included. 

Base Product

Nedávný seznam změn for 2.02

-Revised thrust mapping table to eliminate reverser sounds and thrust drag when engines idled at high a/c speeds.
-Reduction in flaps drag for more realistic performance esp. at full flaps.
-Increased available thrust at lower engine rpm settings at lower speeds
-Increased flaps lift to further match Vref and Vapp speeds.
-Reduced oscillations around roll axis on instrument/localizer approaches.