DC Designs F-14A/B Tomcat Announcement & Discussion

I am quite happy with what we have, but will never turn down the opportunity to take the Super Tomcat for a spin!

Thank you for the detailed responses. I really appreciate it. :slightly_smiling_face:


Hi Jack,

Thank you and Deano for all the answers and information you have provided on this forum! I have read through most of the thread and have a couple of questions relating to RNAV/VNAV and the autopilot.

First, let me say that I have most of the cockpit button toggles bound to my throttle controls. I do notice that sometimes, even though I select the appropriate toggle on my control, the graphics in the cockpit don’t change (the switch doesn’t move), but the tooltip over the switch changes to indicate a change in function.

With that said, I was arriving in KTEB today trying to capture the glidepath on an RNAV approach (RNAV GPS Y Rwy 6). The lateral guidance worked fine, but the glidepath was never captured. As I passed the IF (JUGGY) at the proscribed altitude and started dropping to the FAF (STICC) altitude, I saw the glidepath indicator on the vertical deviation scale, but never saw “G/P” show on the HUD. I continued along, enabling the Approach button, and this immediately took me out of GPS and into VOR mode. I put the plane back into GPS mode, but never caught the glidepath and never saw the GP HUD indicator.

I tried to follow all of the instructions you wrote in your post (#1047) above:
APPROACH SWITCH (upper ACLS ILS switch): Enables Approach mode (with GlideSlope) During an ILS approach (also called precission approach) with a valid ILS frecuency tuned, the plane will try to head the localizer position and catching the Glideslope if succeed. During RNAV approach (also called non preccision approach), will follow a glidepath not displayed in the MFD provided by GPS (However in final approach a manual intervention will be probably required in RNAV, while on ILS the aircraft can land automatically with Autopilot and Autothrottle). For ILS landings, a valid tuned frequency and NAVGPS switch in VOR MODE and AP Master ON is required in order to work (to ensure success, try to enable Approach mode when you were more or less aligned vertically with the GS displayed on the HUD). For RNAV landings, GPS driven is required.”

Is selecting Approach supposed to be taking me out of GPS NAV mode? If so, is switching it back taking me out of Approach mode?

On a separate but related note, should I be able to enable VNAV on that approach, as long as the approach is in the flightplan?

Thank you.

Much appreciatted really!

I think it doesn’t, this is something that happens on all planes. You see, it seems that we are the only ones to implement a switch that disables the GPS, but this seems to have an effect only when there is no active flight plan. When there is an active flight plan it seems that the approach inverts the state that the GPS had at that moment. If it was disabled, it is enabled, and vice versa. We realized with the concorde and it is corrected in the F-15, but not in the f-14 apparently. It is clear that if you do not take a GS it is because the gps is active. You can do a switch reset to make sure the GS is intercepted. That is, if you have to take a detour, do it.

1 Like

VNAV together with autothrottle what it does is fix the speeds during the different phases of flight. From take off to landing if you go with autothrottle and the F-PLAN is active. My idea is to change VNAV for ACLS, this is that you can make the landing with a speed whose calculation is based on an interpolated value, based on GW and real charts, this is already working in F-15 and it works really well. The problem with VNAV is basically that it must also calculate the vertical speed between the aircraft’s altitude and the next WP’s altitude. But there is a problem with MSFS and that is that sometimes the altitude of that WP is 0 if the flight plan has not been set correctly, which means that the plane will crash. That is why I think it is better to replace it with the real function of the plane which is the Auto Carrier landing System.


I will try the switch reset and see if my timing of setting the system back to GPS was faulty.

With respect to your logic, it’s an interesting feature/bug of the system to invert the state of the GPS when selecting Approach when there is a flight plan active. What does the aircraft consider a flight plan?

Let me explain: I use Aivlasoft’s EFBv2 to set up procedures, establish waypoints and Direct Tos and I really like the way they show the plane in real time on the glide slope as well on their charts. EFBv2 writes to the GPS system and updates it whenever a change is made in the routing/procedure, etc. - what they call the “Flight Plan.” However, because of limitations within MSFS, changes to the GPS system directly don’t reflect graphically as updated flight plans. The waypoint information is updated in the cockpit displays, but the path/track is not updated. So, is the system thinking it has an active flight plan or not?

Because of that, I also use the PMS50 GTN750 when I want the in-cockpit flight plan represented graphically when making changes. I just find it a lot less flexible and harder to use than the EFBv2. I will try the same approach both ways and report back when possible if there is a difference between a GPS-only flight plan and a GPS flight plan that is also represented graphically in the cockpit displays.

Yes, I have seen very strange VNAV behavior and it certainly looks like the system is assigning a 0 value to the altitude of many waypoints. The speed that the system selects seems to be too high for approaches also. It sounds like ACLS would be an ideal solution.

What is weird is that even assigning an altitude to a waypoint in the GTN750, and seeing the constraints on the GTN’s map, the plane’s VNAV system still ignores them. Maybe those constraints aren’t making it into the flight plan or into the tables the aircraft’s VNAV system is reading.

A flight plan is any scheduled flight either from the selection menu or from any available browser or any external program that correctly creates a *.pln and loads it. In this case the F-14 does not yet have a Physical FMC but uses one in the background for the logic to work (but we are in the process of including it in the RIO). What you use the GTN750 is at your own risk since it has happened to us lots of times that users have come to us to complain that certain autopilot functions of our planes stopped working or that the screens stopped working directly, that is because mod 750 alters certain base files that are shared by all screens, fmc or devices that have to read these files, and this developer, although he is aware of it, has not yet deigned to solve this problem. Therefore, as long as this developer stops hijacking the base files I will not recommend its use with our planes.

Our VNAV does not read the legs of an FMC, but the variable: A:GPS_WP_NEXT_ALT. Therefore, if the altitude of the next waypoint of the flight plan is correctly defined (either via FMC, menu or external software) and it updates this variable to the correct alt value, it shoudn’t be 0ft, but in reality it is not.


I am going to write this more for memorializing and confirming what you wrote just above, but you are 100% correct and I appreciate your taking the time to explain it.

I did four landings in KTEB (the original approach that I had asked about - RNAV GPS Y Rwy 6). The first was with a flight plan created from the world map selection menu. It worked as you said. The flight plan showed in the instruments and I selected approach mode before the FAF and the autopilot caught it (even though it changed from GPS LNAV ALT on the HUD to TRK FAC ALT G/P on the HUD and still followed the GPS course (and the NAV/GPS switch was still showing GPS was active). Of note, I selected 140 knots as the airspeed and the plane lands about 200 feet too short at that speed.

The second was one where I loaded a flight plan into the GPS system only (no *.pln file) through Aivlasoft EFBv2 and while the GPS flew it, once I selected Approach mode, I got kicked out of GPS mode into NAV and the Navigation mode selector by the “magic switch” also got turned off. Needless to say, nothing worked at that point with respect to the RNAV approach (HUD started showing LOC ALT G/S). I selected GPS and re-enabled the Navigation mode, so lateral guidance worked, but not the G/P.

On the third attempt, I loaded the GTN750 (understood about the pitfalls of using that mod, but it seems to be the only possible way of loading a flight plan that the aircraft will recognize while in the air or without going back to the world map) with the approach and it worked as well as with the original attempt. Again, landed short due to speed.

On the fourth attempt, used the GTN750 again to set the flight plan and everything worked well again, with the exception that I selected 150 knots as the speed. The plane approached almost perfectly (maybe a tad short), much better that at the slower speed.

In none of these attempts did the AP or Auto Throttle seem to disconnect 85 feet above the ground, something I think should have happened.

On the VNAV information, I will see if I can input a *.pln file with the necessary (correct) information.

Thank you so very much again, Jack!


Hello everyone, new pilot with just over 400 hours flight time.

Is this basically correct? I’ve been reading everything but it makes my head hurt. lol

  1. Nav or heading mode until you can pick up LOC.
  2. Switch to LOC. (Back/left side of F14)
  3. Set speed/flaps/gear/dcs (front left side).
  4. Activate ACLS.(2 switches front right side of F14)

I’m trying Autoland JFK 4R ILS (cat II & III) 109.50 everything sets up nice but at the end F14 is off to the left of the runway. Not that big of a deal. I can hand fly it in but want to make sure I’m doing it correctly.
Only item in my community folder is the F15.

BIG!! THANKS!! to the creators of this F14 and for the ongoing customer support. You guys ROCK!! When looking for a new aircraft, I look to you guys first.

Note: I LOVE!! the Grand Canyon videos. I tried it but bounced off the walls a few times. lol

OMG!!! did you guys add a touch and go??? I was going to let the F14 land off runway but in that last photo you can see the F14 throttle up, climb and go ON IT"S OWN. That was so COOL!!!

1 Like

Hi and Wellcome! Let’s see: I would make changes there:

  1. Set your ILS freq and switch to VOR MODE.
  2. Set AP, set altitude (more or less 5000ft).
  3. Set speed/flaps/gear/DLC (front left side).
  4. Use heading mode to align your plane with LOC or RWY using the HDG knob.
  5. Activate ACLS. (when the altitude is slightly below the GSI (vertical deviation). Exactly, the upper switch is approach, the second is ACLS.

LOC switch is not really neccesary, unless you want to catch a Localizer without capturing the Glideslope.

1 Like

CodenameJack447: Hi and thank you for the welcome and your help. :slight_smile:

  1. I set my ILS freq before takeoff as I have a tendency to forget. :frowning: Not sure if I’m setting VOR mode correctly.
  2. I set my Alt 100ft below what the chart has and never have a problem.
  3. auto throttle/flaps/gear/DLC all setup very early. I have a tendency to forget my landing gear. Yes, my Tomcat has been taking a beating. :frowning:
  4. “Use heading mode to align with RWY”. I should have thought of that. Will try on my next flight. In the photo you can see LOC set it to 043 but the chart has the RWY at 044
    Thanks again. :slight_smile:
    Note: I know not much call for it, but a Boeing B-47 Stratojet would be awesome. :slight_smile:

I found an interesting (if somewhat repetitive) article concerning procedures a la what we’ve been discussing. I, at least, found it helpful: Integrated Approach Navigation (IAN) - Review and Procedures - Journal - Flaps 2 Approach

Although some of this doesn’t apply without an FMC, it was exciting to hear from Jack that they are considering putting that into the RIO’s panel.

In any event, this is, by far, my favorite aircraft to fly, and I love being able to use it in so many different scenarios (night, inclement weather, VFR, burning ABs and climbing as high as possibly, etc.).

Thank you again Jack and Dean for all your efforts!


Such a beautiful aircraft. And!! fun to fly. :slight_smile:

This time on landing I just left it on auto everything and used the stick to center the LOC. Yes, I know in real life you can not manipulate the autopilot like that but if MSFS is going to let me :slight_smile:


I don’t know if I’m suppose to tell you or MSFS? but airspeed indicator not working correctly. In the photos you can see it’s stuck at 512 even when on the ground and at a full stop. Will delete F15 from my community folder (so it will be completely empty), restart MSFS and see if it continues to happen.

1 Like

Community folder empty, restarted MSFS, did the same flight and it happened again. When I apply the airbrake to slow down, (as seen in the photo) airspeed will read correct for a time but then freezes. This time at 397. Flight from Atlantic City to JFK 4L with heavy snow.

1 Like

Pitot heat :slight_smile:


LMAO!!! It’s freezing outside and the airspeed indicator freezes… DUH!!! what did you think was going to happen. lol WOW!!! do I feel stupid. :pleading_face:

This is why I would not hesitate to buy a product from you guys. Product is top of the line and customer support is AWESOME!!!

Thanks again for your patience with a newbie. :slight_smile:


Deano1973 looks after us all


Yes, Dean & Jack are ROCK STARS… Wish I could do coding/programing like them.

You two have any new aircraft being released?? Say, I don’t know :thinking: a Boeing B-47 Stratojet. lol

1 Like