Since it's impossible at this point to sync altered flight plans from Airtrack to FSX, it would be nice to have to option to have Airtrack control the heading setting on the FSX autopilot to match the flight plan in Airtrack. That way you can still fly an altered flight plan, albeit with a somewhat less elegant solution.

Of course this could probably never work with Airtrack closed, but it doesn't have to. The issue arises when flying long distance flights, where the STAR can never be known at departure. When flying on VATSIM or IVAO you don't want to pause the flight to update the flight plan in FSX first. Since it's only the last few minutes of the flight, people are likely to have Airtrack running continuously anyway.

With the recent demise of VasFMC I see real potential in Airtrack as a primary navigation system for these kinds of flights, but updating the flight plan in real time is essential to us FSXers. Whilst that feature is in development a simple 'use heading control for LNAV for flight plan updates' setting would be awesome.

Hum, it's an idea ...

The only problem I see there is that by having AirTrack in control (by heading override) would probably generate a less perfect flight path as it wouldn't have information on the capabilities of the aircraft, its rate of turn, etc ... But probably better than nothing.

Still, it would be better for AirTrack to just update the flight plan ... What do people use to make a flight plan in the FSX world? Was it vasFMC? FSX's internal flight plan? Or is the FMC plane specific?

Personally I use RouteFinder:
http://rfinder.asalink.net/free/

An alternative is VATroute which uses a database of routes made by members:
http://www.vatroute.net/

AvliaSoft flight bag is a product worth checking out as well, if just for inspiration. It has built in support for RouteFinder and VATroute:
http://www.aivlasoft.com/products/efb/index.html

I fly some payware planes that have a built in FMC but I also fly some that don't, for those I'd like to use Airtrack as the FMS.

Something else worth checking out would be Prosim737 for sim builders, it's sort of like vasFMC except much better but just for the 737:
http://prosim737.com/

Prosim737 uses a different system where it basically overrides the FSX autopilot completely, instead it takes over control of the plane with FSUIPC. You control the software, the software controls the plane.

VasFMC had a system where you specified details about the plane you're flying in a .cfg file, here's the contents of the .cfg file for a Boeing 747-400:

ac_type_icao=B744
checklist_filename=airbus.txt
fbw_bank_controller_d_gain=0.2
fbw_bank_controller_i_gain=5
fbw_bank_controller_i_to_p_part_response_factor=0.5
fbw_bank_controller_max_bank_rate_deg_s=15
fbw_bank_controller_max_forced_bank=45
fbw_bank_controller_max_idle_bank=30
fbw_bank_controller_p_gain=3.8
fbw_enabled=0
fbw_pitch_controller_d_gain=5
fbw_pitch_controller_i_gain=5
fbw_pitch_controller_max_negative_pitch=-15
fbw_pitch_controller_max_pitch_rate_deg_s=5
fbw_pitch_controller_max_positive_pitch=30
fbw_pitch_controller_p_gain=15
flap_detent_degree_list=1,5,10,20,25,30
flch_controller_ias_trend_factor=10
flch_controller_ias_trend_target_limit=15
flch_controller_n1_trend_factor=5.5
flch_controller_vs_change_factor=100
flch_controller_vs_change_limit=250
flch_controller_vs_cmd_diff_limit=1250
flch_controller_vs_cmd_limit=5000
idle_thrust=12
idle_thrust_approach=32
idle_thrust_engine_anti_ice=30
loc_hdg_boost_factor=8
n1_correction_factor=1
profile_name=B747-400 MSFS STD
slat_detent_degree_list=1
speed_controller_max_trend=2
speed_controller_rate_factor=14
speed_controller_trend_boost_factor=12
speed_controller_vs_trend_boost_factor=0.8
speed_controller_wrong_direction_trend_boost_factor=1.5
throttle_controller_max_trend=7
throttle_controller_rate_factor=13
throttle_controller_trend_boost_factor=4
thrust_change_rate_reduce_factor_climb=5
thrust_change_rate_reduce_factor_descent=7

I see ... what I meant was what FSX uses to control LNAV, so it seems that each system / add-on / plane receives and controls its own flight plan. This is what makes it difficult to be compatible with every plane :(

We'll see ...

Hmmm, I'm trying to think along with ya. I don't think I've seen or heard of any application updating the vanilla FSX flight plan without interruption before, but it might be possible.

I agree it'd be impossible to integrate with every addon out there but I don't think you'd have to. For those addons that have good flight plan management the functionality to add a STAR is already there. But for every plane that uses the default FSX flight plan management, there is no real way to adjust the flight plan to include an accurate STAR, ever. If you were to craft that ability using an application on the iPad, that'd be new territory I believe.

If you're interested in going on Skype sometime I'd be happy to share some thoughts with you.

Thanks!

Just sent you an email.

In the meantime, while there's no fllight plan update, one possible way to follow up a STAR is to enter it in AirTrack and then manually following the drawing on the MFD :)