Flight Plans the INS and AFCS

[Hawk]

Hi,

I recently purchased the F-4E Phantom II. I have read a great deal of the F-4E PDF (including the PDFs from MilViz) and watched a few videos available on the Internet but I'm having issues learning/using the INS and AFCS. It may be I'm expecting it to do something that it's not modeled to do so I'm hoping the folks at MilViz can clear up some things for me.

1) I realize I'm dealing with an INS system geared to LAT/LON inputs. I found some information on loading a "target" (destination) LAT/LON into the NAV panel (rear cockpit), I presume this is similar to a single leg flight plan? Then I tried to learn more about loading a multi-leg flight plan. I found and watched several online videos, one showed the user creating a flight plan using PLAN-G (which I use periodically) but my primary flight planner is the Aivlasoft EFB. I presume if you can use PLAN-G there should be no problems using another flight planner as long as the flight plan is recognized by the sim? I confirmed this when I loaded a flight plan using my Aivlasoft EFB and during a test flight watched the HSI indicator provide proper tracking information when the NAV COMP was selected. I had problems on various test flights loading the flight plan because I believe you must do certain things in a specific sequence (this is vague and the HOW-TO unclear), such as when to load the flight plan into the simulator compared to when you load the F-4 aircraft. Maybe someone could provide more specific details on this.

2) This brings forth the next question. When I engaged (coupled) the AFCS to the NAV COMP it would not automatically keep the aircraft on the planned flight path? My aircraft strayed from the planned flight path if I did not manually fly it. Per information from the PDFs and videos I presume the TGT2 selection on the NAV panel (rear cockpit) is supposed to provide the loaded flight plan data to the AFCS? So, correct my understanding if it is flawed, I should use the TGT1 setting if I want the AFCS to use the LAT/LON entered directly into the NAV panel as a single "target" (destination) LAT/LON. I should use the TGT2 setting if I want the AFCS to use the flight plan loaded into the simulator by a program such as PLAN-G or the Aivlasoft EFB? Can someone explain in more detail what each position of this switch is doing, such as the RESET position (???) because I can not find any further information on it. If the AFCS does not automatically track the loaded flight plan then does this mean I must always manually fly the aircraft using the HSI indications for navigation while coupled to the NAV COMP?

3) Must the a) Auto Present Position Update and b) Auto Steerpoint Sequence in the MilViz Configuration Manager be checked for the INS to automatically track a loaded flight plan? If these are not checked then my understanding is that I must manually load the "present" (starting) position into the INS before the flight and manually sequence the steerpoints (how this is done I have no clue, I could not find information on this). It's great that we have a choice to have these taken care of, but if I do not check these then can someone explain the HOW-TO?

Thanks for any help,
Hawk

[Victory103]

2). The AFCS will not couple to your INS imputed flightplan on TGT2, so "do some of that pilot stuff" is required. Correct, TGT1 is a direct-to waypoint you set, switch the knob to RESET to save those coords to memory. If you want your virtual Wizzo/GIB to work, use the "leap frog operation" method from the F-4 flight manual to enter a complete flightplan manually in flight.

[JonathanBleeker]

1) Correct on the single leg. First of all, to clear a few things up, the TGT1 position will give you bearing/distance to the lat/lon set on the TGT lat/lon counters. The TGT2 is a lat/lon stored in memory. You can store the lat/lon from the TGT lat/lon counters into this memory position by moving the mode knob to reset and back as Victory103 described.

That said, you can load flightplans in any way you want (before or after selecting the F-4), by going to the Addons menu->Milviz F-4 Phantom II->Flightplan menu. A dialog box will come up with the various options (reload flightplan, select active waypoint, auto sequence waypoints etc). The Select Active Waypoint will give you a list of waypoints in the flightplan for you to select. The active waypoint will be stored automatically in the TGT2 memory position so you would just have to set the mode to TGT2 and you would get the distance/bearing directions in the NAV COMP modes on the HSI and ADI.

2) As Victory103 said, the AFCS will not fly the flightplan for you. It will hold whatever attitude or altitude you are at when engaging it or after you move and center the stick. So yes you have to manually fly the flightplan.

3) The INS drifts over time so the indicated position doesn't actually match up with your actual position. The auto present position update option takes care of updating the position for you. The Auto steerpoint sequence as described above will automatically sequence through the points in your flightplan, placing them in TGT2 memory for you to follow in TGT2 mode.

For how to set up the INS, see this video: https://www.youtube.com/watch?v=eHDi-RXT8AI

[Hawk]

1) Correct on the single leg. First of all, to clear a few things up, the TGT1 position will give you bearing/distance to the lat/lon set on the TGT lat/lon counters. The TGT2 is a lat/lon stored in memory. You can store the lat/lon from the TGT lat/lon counters into this memory position by moving the mode knob to reset and back as Victory103 described.

That said, you can load flightplans in any way you want (before or after selecting the F-4), by going to the Addons menu->Milviz F-4 Phantom II->Flightplan menu. A dialog box will come up with the various options (reload flightplan, select active waypoint, auto sequence waypoints etc). The Select Active Waypoint will give you a list of waypoints in the flightplan for you to select. The active waypoint will be stored automatically in the TGT2 memory position so you would just have to set the mode to TGT2 and you would get the distance/bearing directions in the NAV COMP modes on the HSI and ADI.

2) As Victory103 said, the AFCS will not fly the flightplan for you. It will hold whatever attitude or altitude you are at when engaging it or after you move and center the stick. So yes you have to manually fly the flightplan.

3) The INS drifts over time so the indicated position doesn't actually match up with your actual position. The auto present position update option takes care of updating the position for you. The Auto steerpoint sequence as described above will automatically sequence through the points in your flightplan, placing them in TGT2 memory for you to follow in TGT2 mode.

For how to set up the INS, see this video: https://www.youtube.com/watch?v=eHDi-RXT8AI

Thanks Victory103 and Jonathan, this helps clear up some things.

1a) If I understand your explanations correctly TGT1 is tied directly to the LAT/LON counters and TGT2 is similar but saving only one LAT/LON at a time (even if a multi-leg flight plan is loaded) in it's "memory slot", the RESET being used only to move the LAT/LON from TGT1 to TGT2. By doing this it will allow the pilot to load a new LAT/LON into TGT1 after moving the current one to TGT2 and so on...in effect allowing the pilot to "leap frog" the coordinates. If a multi-leg flight plan is loaded then the first waypoint is stored in TGT2 automatically and sequenced IF "Auto Steerpoint Sequencing" is checked in the configuration manager? You didn't mention it quite like this, but I presume if AUTO STEERPOINT SEQUENCING is not checked in the configuration manager there is NO sequencing of waypoints for a multi-leg flight plan whatsoever? In other words there is no way to sequence the waypoints in a loaded multi-leg flight plan from the cockpit, this can be managed only by the configuration manager?

1b) Johnathan, you mentioned that various options show up under the Addons menu in the sim, one being "reload flight", curious, I looked there for that one but didn't see it listed? That is what I saw mentioned in one of the videos but I could not find it, causing some confusion. Is there something that must be done for it to show in the menu? In other words, is there something that "triggers" that menu selection to show?

2a) I suspected what you and Victory103 have confirmed, that the AFCS just maintains altitude and attitude and that the pilot MUST fly the aircraft along the flight path, no problem, that is what I have been doing on my test flights. Don't think I'll be doing any flights across the pond any time soon but even for those short flights I wish MilViz would change (or provide an option for it)...to allow the ALTITUDE switch to ignore any stick movement...to keep it from disengaging. On my hardware this seems to be extremely sensitive and I can not make course corrections without disengaging the altitude hold. I know I can just reengage it, but it would be a nice option. Thanks for the link to the video, I think this clears up most of the questions I have for now. Gotta get back into the cockpit and try some full fledged IFR flights and approaches and put everything to the test.

Once again thanks for the help!

[JonathanBleeker]

1b)The menu items are as follows:
Addons->Milviz F-4 Phantom II will give 3 options. Flightplan Menu, Signal External Airflow Start, and Shared pit menu. You will want to select the Flight Plan menu. I forgot that the old Reload Flightplan (not Reload Flight) was removed and the whole procedure automated so that it will automatically check for an active flightplan in the sim when you open the flight plan menu.

1a) You mostly got it right. However, you can also enable/disable auto steerpoint sequencing from the flight plan menu mentioned above as well as the config manager. If you disable it, you can still manually select the active steerpoint from the above mentioned flight plan menu.

2) You can increase the Control Stick Steering (CSS) deadzones which disengage the autopilot on the second page of the ACM. That will solve your problem.

[Hawk]

Johnathan, sorry for the late reply, have a heavy work schedule. You have resolved everything previously discussed. I found all the menu items you mentioned. I loaded an active flight plan and when I rechecked the menu selections they were there as you described. I have also increased the deadzones for the CSS and will experiment with everything I have learned on the next few flights, I'm sure everything will work fine now. Thanks a bunch!

Cheers!