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FS2004 Boeing 747 Classic
- Thread starter FSMuseum
- Start date
- Messages
- 246
- Country
Thanks! It's progressing well, my attention has briefly switched back to an AI Boeing 707 project that I may show here soon.
I am putting the final touches on misc features such as the radios and night lighting. I intend to send the panel to my beta tester sometime in the next couple months and then once all the kinks get worked out I will release it probably close to Q2, maybe Q3 2024.
Great, good luck with the last miles
!
Hi there! Very interesting project you have going on there.
I'm curious, do you have a sample or video containing the attitude comparator warning buzz sound? I'd be interested in hearing what it sounded like. This is in connection with the Korean Cargo 8509 accident.
- Messages
- 246
- Country
Yes I do, send me a PM and I'll discuss it with you.
Wilco! Thanks!
- Messages
- 3
- Country
Amazing work! Thanks for contributing! If you need any help with testing or whatever,give me a buzz 
.
Brgds,
Steven
.Brgds,
Steven
- Messages
- 246
- Country
Hey all,
Some quick updates from behind the scenes.
I think the coolest thing that has happened since the last update has been the implementation of the triple channel autoland fail-operational Sperry SPZ-1-922 autopilot (what a mouthful!). Originally this was intended to be an option that I would include later down the line, but I deicded that since I am making a PW 7R equipped late model 747 classic, it would only be fitting to include the most common/most capable variant of the autoflight system that came on these later build aircraft. I have also updated the FMA accordingly.
Rest assured, this is not just a visual change and a new autopilot paddle. This autopilot is considerably more capable than the dual channel autopilot of earlier models.
Automatic Go Around: This unit, with the -922 computer installed in the avionics bay, can fly a go around for you (note the arrow displays on the FMA). After GS capture, pressing the TO/GA switches (a clickspot on the autopilot panel is available for quick access) will cause the autothrottles to go to EPR mode and switch to GA thrust, the autopilot will pitch to maintain 800 fpm climb with flaps 25 or more, or will pitch to maintain speed with flaps less than 25, and the FD will command the same. This mode can only be exited by manual intervention of the pilot, by switching the heading mode knob out of ILS, which will cause the AP to disengage. It can then be re-engaged in the required modes.
Triple Channel Autoland: This autopilot can perform fail operational autoland, meaning that if any single channel out of the 3 engaged were to fail or disengage, the autopilot can continue to a successful automatic landing with only the two remaining channels. This was a big factor in getting CAT IIIb authorization for the 747 classic.
Automatic Rollout Control: Upon performing an automatic landing, beginning at 5 feet radio altitude, the autopilot will begin controlling the rudder and nose-wheel to maintain the runway centerline (actually, it maintains the localizer beam center, which is why some approaches cannot be done with autoland, if the beam is not correctly aligned or has too much anomaly). Unfortunately, due to FS2004's method of simulating ground roll dynamics, I could not simulate this system exactly as it exists in the real aircraft (believe me, I tried! I have the documents!). However, I have simulated a very close approximation of the real system that meets the requirements set out by the FAA for an automatic landing that functions very well in FS2004.
Something else I have been working on is tweaking the night lighting. I got to experience another ride on the Delta 737-200 sim in Atlanta as well as acquiring a few more instruments from real 747 classics and hooking them up to power sources to see the lights. I have tweaked my lighting accordingly since the last time you saw it based on my direct observations, a couple of examples can be seen below.
That's about all for now. I am still implementing finishing touches and finishing up various more minor systems like radios and such.
Some quick updates from behind the scenes.
I think the coolest thing that has happened since the last update has been the implementation of the triple channel autoland fail-operational Sperry SPZ-1-922 autopilot (what a mouthful!). Originally this was intended to be an option that I would include later down the line, but I deicded that since I am making a PW 7R equipped late model 747 classic, it would only be fitting to include the most common/most capable variant of the autoflight system that came on these later build aircraft. I have also updated the FMA accordingly.
Rest assured, this is not just a visual change and a new autopilot paddle. This autopilot is considerably more capable than the dual channel autopilot of earlier models.
Automatic Go Around: This unit, with the -922 computer installed in the avionics bay, can fly a go around for you (note the arrow displays on the FMA). After GS capture, pressing the TO/GA switches (a clickspot on the autopilot panel is available for quick access) will cause the autothrottles to go to EPR mode and switch to GA thrust, the autopilot will pitch to maintain 800 fpm climb with flaps 25 or more, or will pitch to maintain speed with flaps less than 25, and the FD will command the same. This mode can only be exited by manual intervention of the pilot, by switching the heading mode knob out of ILS, which will cause the AP to disengage. It can then be re-engaged in the required modes.
Triple Channel Autoland: This autopilot can perform fail operational autoland, meaning that if any single channel out of the 3 engaged were to fail or disengage, the autopilot can continue to a successful automatic landing with only the two remaining channels. This was a big factor in getting CAT IIIb authorization for the 747 classic.
Automatic Rollout Control: Upon performing an automatic landing, beginning at 5 feet radio altitude, the autopilot will begin controlling the rudder and nose-wheel to maintain the runway centerline (actually, it maintains the localizer beam center, which is why some approaches cannot be done with autoland, if the beam is not correctly aligned or has too much anomaly). Unfortunately, due to FS2004's method of simulating ground roll dynamics, I could not simulate this system exactly as it exists in the real aircraft (believe me, I tried! I have the documents!). However, I have simulated a very close approximation of the real system that meets the requirements set out by the FAA for an automatic landing that functions very well in FS2004.
Something else I have been working on is tweaking the night lighting. I got to experience another ride on the Delta 737-200 sim in Atlanta as well as acquiring a few more instruments from real 747 classics and hooking them up to power sources to see the lights. I have tweaked my lighting accordingly since the last time you saw it based on my direct observations, a couple of examples can be seen below.
That's about all for now. I am still implementing finishing touches and finishing up various more minor systems like radios and such.
- Messages
- 2,204
- Country
FSMuseum you are doing an Amazing Job! I was checking this thread since years, being sad it was just for FS9.... until few days ago when the 747 Classic was announced for MSFS here: https://www.fsdeveloper.com/forum/threads/boeing-747-classic.458548/ , reading you were behing that one too was such a good news for me! I'm really looking forward to it! Im already looking for the flights I'll do with it (Too Soon?)
(Too Soon?)
- Messages
- 246
- Country
Hey all,
Back again with another update, and this one is one I've been excited (but patiently waiting) to show you for quite some time. This is one of the ideas that I first had several years ago but have only now finally managed to bring to life. A very rewarding feeling
There's a lot to go over here, so let's not dally.
This is a module that I have yet to come up with a clever name for, but perhaps you all can help me with that. If you've ever sat in the instructor's seat of a full motion CAE Flight Sim, you will know that the instructor has access to a number of options concerning the simulation, namely the performance data inputs, CG envelope, and lots of miscellaneous options. I thought it would be cool to recreate this kind of menu design in the form of an in-simulator status and options screen.
During initial load-up, you will be greeted with this on the main panel:
This initializing is real and very important: FS2004 does not start the gauge loading exactly the same way every time it is loaded, so to ensure that the panel state you have selected loads properly and fully, I have programmed a short 10 second initialization period.
Once initialization is done, the screen will auto-update and bring you to the Status page:
The status page is very simple but powerful for us flight sim users. This page includes the direct weight and CG information of the aircraft as loaded into the simulator, plotted against the real CG envelope for the aircraft. You can use this to check that any weight changes you have made are reflected accurately (for example, checking if an external program like FSCaptain has properly loaded your aircraft), as well as checking that the CG is within limits. The CG being within limits really matters here - the flight model is extremely accurate in this respect!
You will also notice the warning/malfunction pane: This area will display warnings and malfunctions that are relevant to the simulation, such as the ZFW or CG being out of limits, or an impending generator failure due to overloading. The generators can be made to fail in dramatic fashion if you really goof it up. Several other systems-based consequences will appear in this area if they are relevant. If all is functioning well, the pane appears blank as shown above.
Using the status page, there should be no surprises to the user in any regard to the systems or weight/balance simulation.
Up next, using the buttons now visible at the bottom, you can navigate to the Performance Calculation page. This one is the one I am most excited for right now (though Triple Crew is pretty fun too!)
This performance calculation is very involved, this is no simple V1/VR/V2 lookup calculator.
This calculator is most akin to (and has been somewhat themed after) the program TOPCAT, well known by us serious simmers to give very accurate takeoff and landing performance calculation based on the same methods used in the real world.
You'll note that the calculator appears incomplete in the T/O profile section. This section has more to do with the triple crew part of this module, more on that later.
As shown above, the output window is currently blank. By default, on first load, the calculator has no flap setting selected. This is to ensure that the user doesn't nuisance-click the big CALCULATE button and then forget to change the performance information later. In fact, any time a change is made to any of the inputs at the left, or any time the actual weight of the aircraft in the sim suddenly changes by more than 2000 lbs (such as the user changing payload settings), the output window blanks! Safety, safety, safety.
Once all the other inputs have been modified and a flap setting chosen, clicking calculate will present you with the appropriate information relevant to your takeoff. As an example, here is the calculator using real world weather inputs for a runway 25 takeoff at KDEN:
There's a lot of information, but none of it should seem unfamiliar to a seasoned 742 driver!
A stabilizer trim setting (including corresponding green band switch setting), input OAT, the limit weight and limiting category for said weight, correctly adjusted V1, VR, and V2, and the EPR setting are all correctly calculated for any given set of inputs. These figures are based on corrected runway, takeoff, accelerate-stop distances, and pack config corrections directly from the 747 AFM for the 7R engine. At the bottom, the optimum climb speed for the selected takeoff weight is supplied.
You'll also note that all of this information is also supplied for a reduced thrust takeoff, if you so choose and if applicable. The limit weight for the reduced thrust takeoff is always either the current weight, or the minimum weight where V1 = VMCG, whichever is higher. The reduced thrust takeoffs also accurately adjust the V speeds when appropriate.
If you try to input information that results in a maximum takeoff weight that is less than the input takeoff weight, you will be greeted with a message:
You will also get a red alert if the takeoff runway is not sufficiently long enough to reach VMCG speed, if that is a limiting factor.
The speeds calculated by this calculator have been tested numerous times and so far, provided that you perform a rejected takeoff correctly and no later than V1, you will stop on the runway, every time. Of course, this is using my modified SIM1.DLL file the corrects the overly-high ground friction that exists by default in FS2004. Without this corrected file, your takeoff distances will be longer but braking distances will be shorter. My calculator will not be made to support the default ground friction, so for accurate results you should use my modified file.
You can switch between LBS and KG inputs if you want (which will also change the aircraft status page to the selected input), but by default the units that you have selected in your simulator will be what is chosen upon loading.
This functionality is repeated on the approach and landing page, but that is not complete enough to show yet...
You'll notice too, as mentioned earlier, the T/O Profile section which is incomplete (the runway condition section is also incomplete, as I am still implementing the corrections for wet runways, etc.)
This section has more to do with the Triple Crew part of this module, and the name should tell you everything you need to know about what it basically is. The real 742 is a triple crew aircraft, and managing all of the systems in busy phases of flight is daunting, hence why Boeing automated these functions on the 400 onward.
The T/O Profile section is your takeoff briefing to your virtual flight engineer: you will tell him the takeoff profile including when to switch to CLB thrust, what the acceleration height is in both all engines and engine out conditions, and he will faithfully follow your instructions during the takeoff climbout. He switches to CLB thrust for you, ensures the throttles come back to the correct setting, and manages reconfiguring the fuel and pneumatics systems all on his own, so that you can concentrate on flying the aircraft. The F/O will retract the gear and flaps for you during this time.
The flight engineer isn't only limited to takeoff and climbout, in fact he is active throughout the entire flight if enabled. He will accurately set the fuel configuration, change the packs over to half flow at cruise altitude, and lots of other functions that are all based on real automatic triggered flows at all phases of flight, allowing you to simply monitor him and concentrate on flying and checklists.
I am also currently working out if it is possible to get the virtual F/O to do holding patterns for you if you so desire.
And of course, using the triple crew menu, you will be able to enable or disable these crew members entirely, or disable only certain functions of them, all fully customizable to your preferred method of using them. Disable them completely for a challenging three-man experience! If you change your mind, simply re-enable them any time and they will automatically take over their duties without any complaints.
And finally...
Let's talk some flight model nonsense for a few moments.
If you're a real pilot or aerodynamicist, you'll know that most conventionally configured aircraft experience ground effect in a manner not quite accurate to what most simulators provide you.
Ground effect is much more than just an augmentation to your lift, there are also significant drag and pitch moment changes.
Unfortunately, I have not found out how to augment drag reliably with the tools I have without sacrificing functionality elsewhere, but pitching moment due to ground effect is something I can proudly say is accurately simulated in my flight model.
Now, if you're familiar with the FS2004 flight model, you must be scratching your head. The default flight model gives us developers no access to anything relating to change of pitch moment due to height over the ground, and you would be correct in that assertion! So how have I done this you ask? Well...
I briefly hijack your aircraft when the ground speed is over 100 knots and the aircraft is below 85 feet! Simple!
Joking aside, that is pretty much what I am doing. I have a gauge that is constantly writing to the stabilizer position when the above conditons are true. This gauge uses the real world data for pitching moment caused by ground effect for the 747 with appropriate adjustments for AoA and flap setting, converts that into a stabilizer trim position, and takes over the stabilizer from you during the takeoff roll and initial climbout, and during the landing flare and rollout.
The change in pitching moment at high AoA near the ground can be equivalent to several degrees of nose down trim, so needless to say, its big and important!
Once the above conditions are no longer true, the stabilizer will return to the setting that it was at initially before being taken over. During takeoff climbout, a ground effect multiplier based on current radio altitude is active, and will naturally reach zero by 85 feet, meaning the stabilizer will return naturally and correctly to the original setting during climbout. However, there is also a check that forces the stabilizer to its original setting no matter what once below 100 kts GS or above 85 feet, just in case a temporary lag spike or glitch should cause weirdness to occur.
And of course, because this is directly modifying the flight characteristics in ways that the user is not familiar with, the stabilizer gauge WILL show what is happening to your stabilizer, so you can watch it move in real time during ground effect if you want. And, just in case, there is an option to completely disable this function if you do not like it, however you will note that takeoff rotation and landing flare will be much more sensitive without this function enabled.
Alright... phew... that's everything for now! See you again soon for another update as we get closer to beta and release!
Back again with another update, and this one is one I've been excited (but patiently waiting) to show you for quite some time. This is one of the ideas that I first had several years ago but have only now finally managed to bring to life. A very rewarding feeling
There's a lot to go over here, so let's not dally.
This is a module that I have yet to come up with a clever name for, but perhaps you all can help me with that. If you've ever sat in the instructor's seat of a full motion CAE Flight Sim, you will know that the instructor has access to a number of options concerning the simulation, namely the performance data inputs, CG envelope, and lots of miscellaneous options. I thought it would be cool to recreate this kind of menu design in the form of an in-simulator status and options screen.
During initial load-up, you will be greeted with this on the main panel:
This initializing is real and very important: FS2004 does not start the gauge loading exactly the same way every time it is loaded, so to ensure that the panel state you have selected loads properly and fully, I have programmed a short 10 second initialization period.
Once initialization is done, the screen will auto-update and bring you to the Status page:
The status page is very simple but powerful for us flight sim users. This page includes the direct weight and CG information of the aircraft as loaded into the simulator, plotted against the real CG envelope for the aircraft. You can use this to check that any weight changes you have made are reflected accurately (for example, checking if an external program like FSCaptain has properly loaded your aircraft), as well as checking that the CG is within limits. The CG being within limits really matters here - the flight model is extremely accurate in this respect!
You will also notice the warning/malfunction pane: This area will display warnings and malfunctions that are relevant to the simulation, such as the ZFW or CG being out of limits, or an impending generator failure due to overloading. The generators can be made to fail in dramatic fashion if you really goof it up. Several other systems-based consequences will appear in this area if they are relevant. If all is functioning well, the pane appears blank as shown above.
Using the status page, there should be no surprises to the user in any regard to the systems or weight/balance simulation.
Up next, using the buttons now visible at the bottom, you can navigate to the Performance Calculation page. This one is the one I am most excited for right now (though Triple Crew is pretty fun too!)
This performance calculation is very involved, this is no simple V1/VR/V2 lookup calculator.
This calculator is most akin to (and has been somewhat themed after) the program TOPCAT, well known by us serious simmers to give very accurate takeoff and landing performance calculation based on the same methods used in the real world.
You'll note that the calculator appears incomplete in the T/O profile section. This section has more to do with the triple crew part of this module, more on that later.
As shown above, the output window is currently blank. By default, on first load, the calculator has no flap setting selected. This is to ensure that the user doesn't nuisance-click the big CALCULATE button and then forget to change the performance information later. In fact, any time a change is made to any of the inputs at the left, or any time the actual weight of the aircraft in the sim suddenly changes by more than 2000 lbs (such as the user changing payload settings), the output window blanks! Safety, safety, safety.
Once all the other inputs have been modified and a flap setting chosen, clicking calculate will present you with the appropriate information relevant to your takeoff. As an example, here is the calculator using real world weather inputs for a runway 25 takeoff at KDEN:
There's a lot of information, but none of it should seem unfamiliar to a seasoned 742 driver!
A stabilizer trim setting (including corresponding green band switch setting), input OAT, the limit weight and limiting category for said weight, correctly adjusted V1, VR, and V2, and the EPR setting are all correctly calculated for any given set of inputs. These figures are based on corrected runway, takeoff, accelerate-stop distances, and pack config corrections directly from the 747 AFM for the 7R engine. At the bottom, the optimum climb speed for the selected takeoff weight is supplied.
You'll also note that all of this information is also supplied for a reduced thrust takeoff, if you so choose and if applicable. The limit weight for the reduced thrust takeoff is always either the current weight, or the minimum weight where V1 = VMCG, whichever is higher. The reduced thrust takeoffs also accurately adjust the V speeds when appropriate.
If you try to input information that results in a maximum takeoff weight that is less than the input takeoff weight, you will be greeted with a message:
You will also get a red alert if the takeoff runway is not sufficiently long enough to reach VMCG speed, if that is a limiting factor.
The speeds calculated by this calculator have been tested numerous times and so far, provided that you perform a rejected takeoff correctly and no later than V1, you will stop on the runway, every time. Of course, this is using my modified SIM1.DLL file the corrects the overly-high ground friction that exists by default in FS2004. Without this corrected file, your takeoff distances will be longer but braking distances will be shorter. My calculator will not be made to support the default ground friction, so for accurate results you should use my modified file.
You can switch between LBS and KG inputs if you want (which will also change the aircraft status page to the selected input), but by default the units that you have selected in your simulator will be what is chosen upon loading.
This functionality is repeated on the approach and landing page, but that is not complete enough to show yet...
You'll notice too, as mentioned earlier, the T/O Profile section which is incomplete (the runway condition section is also incomplete, as I am still implementing the corrections for wet runways, etc.)
This section has more to do with the Triple Crew part of this module, and the name should tell you everything you need to know about what it basically is. The real 742 is a triple crew aircraft, and managing all of the systems in busy phases of flight is daunting, hence why Boeing automated these functions on the 400 onward.
The T/O Profile section is your takeoff briefing to your virtual flight engineer: you will tell him the takeoff profile including when to switch to CLB thrust, what the acceleration height is in both all engines and engine out conditions, and he will faithfully follow your instructions during the takeoff climbout. He switches to CLB thrust for you, ensures the throttles come back to the correct setting, and manages reconfiguring the fuel and pneumatics systems all on his own, so that you can concentrate on flying the aircraft. The F/O will retract the gear and flaps for you during this time.
The flight engineer isn't only limited to takeoff and climbout, in fact he is active throughout the entire flight if enabled. He will accurately set the fuel configuration, change the packs over to half flow at cruise altitude, and lots of other functions that are all based on real automatic triggered flows at all phases of flight, allowing you to simply monitor him and concentrate on flying and checklists.
I am also currently working out if it is possible to get the virtual F/O to do holding patterns for you if you so desire.
And of course, using the triple crew menu, you will be able to enable or disable these crew members entirely, or disable only certain functions of them, all fully customizable to your preferred method of using them. Disable them completely for a challenging three-man experience! If you change your mind, simply re-enable them any time and they will automatically take over their duties without any complaints.
And finally...
Let's talk some flight model nonsense for a few moments.
If you're a real pilot or aerodynamicist, you'll know that most conventionally configured aircraft experience ground effect in a manner not quite accurate to what most simulators provide you.
Ground effect is much more than just an augmentation to your lift, there are also significant drag and pitch moment changes.
Unfortunately, I have not found out how to augment drag reliably with the tools I have without sacrificing functionality elsewhere, but pitching moment due to ground effect is something I can proudly say is accurately simulated in my flight model.
Now, if you're familiar with the FS2004 flight model, you must be scratching your head. The default flight model gives us developers no access to anything relating to change of pitch moment due to height over the ground, and you would be correct in that assertion! So how have I done this you ask? Well...
I briefly hijack your aircraft when the ground speed is over 100 knots and the aircraft is below 85 feet! Simple!
Joking aside, that is pretty much what I am doing. I have a gauge that is constantly writing to the stabilizer position when the above conditons are true. This gauge uses the real world data for pitching moment caused by ground effect for the 747 with appropriate adjustments for AoA and flap setting, converts that into a stabilizer trim position, and takes over the stabilizer from you during the takeoff roll and initial climbout, and during the landing flare and rollout.
The change in pitching moment at high AoA near the ground can be equivalent to several degrees of nose down trim, so needless to say, its big and important!
Once the above conditions are no longer true, the stabilizer will return to the setting that it was at initially before being taken over. During takeoff climbout, a ground effect multiplier based on current radio altitude is active, and will naturally reach zero by 85 feet, meaning the stabilizer will return naturally and correctly to the original setting during climbout. However, there is also a check that forces the stabilizer to its original setting no matter what once below 100 kts GS or above 85 feet, just in case a temporary lag spike or glitch should cause weirdness to occur.
And of course, because this is directly modifying the flight characteristics in ways that the user is not familiar with, the stabilizer gauge WILL show what is happening to your stabilizer, so you can watch it move in real time during ground effect if you want. And, just in case, there is an option to completely disable this function if you do not like it, however you will note that takeoff rotation and landing flare will be much more sensitive without this function enabled.
Alright... phew... that's everything for now! See you again soon for another update as we get closer to beta and release!
Last edited:
- Messages
- 505
- Country
Loving the addition of the fail-operational autoland, which almost all our aircraft had and which was very good in practice. Not quite as buttery smooth as the A346, but very impressive. It's 22 years since I last flew the Queen, but I'm looking forward to reviving those memories in the MSFS version...
- Messages
- 1
- Country
@FSMuseum This really is outstanding work - such a shame the old, buggy, RFP 742 is the only viable 747 classic in the Microsoft world until now (really enjoyed your video all about it).
I was disappointed when JF canned their P3D 747 after teasing so much as it's a sorely missed AC in flightsim hangars around the world.
Best of luck with the remaining build - looks incredibly feature-rich and complex to programme.
I was disappointed when JF canned their P3D 747 after teasing so much as it's a sorely missed AC in flightsim hangars around the world.
Best of luck with the remaining build - looks incredibly feature-rich and complex to programme.
- Messages
- 246
- Country
It's going well! At the moment I'm working on a couple other little projects to take a break from it since I've done a lot of work on the 747 lately. The most recent addition has been a completely re-written and redesigned autothrottle system. Since documentation for the real system is virtually non-existent outside of a somewhat helpful patent document for the system from Boeing, I've had to design the system myself using data from NASA tests of systems with similar design intentions, and it's been going pretty well. The new autothrottle incorporates very accurate speed control across the whole flight envelope as well as having accurate gust response filtering and EPR control law. Once I come back to the 747 I'll probably be focusing on getting the remaining panel graphics finished and programming the few remaining subsystems that I've neglected so far.
Just for fun, here is the block diagram of the autothrottle speed control loop that I've designed! The final system will probably look different from this due to gain tuning and final tests.
Just for fun, here is the block diagram of the autothrottle speed control loop that I've designed! The final system will probably look different from this due to gain tuning and final tests.
Last edited:
- Messages
- 1
- Country
Can't put into words how excited I am!Hey all,
Back again with another update, and this one is one I've been excited (but patiently waiting) to show you for quite some time. This is one of the ideas that I first had several years ago but have only now finally managed to bring to life. A very rewarding feeling
There's a lot to go over here, so let's not dally.
This is a module that I have yet to come up with a clever name for, but perhaps you all can help me with that. If you've ever sat in the instructor's seat of a full motion CAE Flight Sim, you will know that the instructor has access to a number of options concerning the simulation, namely the performance data inputs, CG envelope, and lots of miscellaneous options. I thought it would be cool to recreate this kind of menu design in the form of an in-simulator status and options screen.
During initial load-up, you will be greeted with this on the main panel:
This initializing is real and very important: FS2004 does not start the gauge loading exactly the same way every time it is loaded, so to ensure that the panel state you have selected loads properly and fully, I have programmed a short 10 second initialization period.
Once initialization is done, the screen will auto-update and bring you to the Status page:
The status page is very simple but powerful for us flight sim users. This page includes the direct weight and CG information of the aircraft as loaded into the simulator, plotted against the real CG envelope for the aircraft. You can use this to check that any weight changes you have made are reflected accurately (for example, checking if an external program like FSCaptain has properly loaded your aircraft), as well as checking that the CG is within limits. The CG being within limits really matters here - the flight model is extremely accurate in this respect!
You will also notice the warning/malfunction pane: This area will display warnings and malfunctions that are relevant to the simulation, such as the ZFW or CG being out of limits, or an impending generator failure due to overloading. The generators can be made to fail in dramatic fashion if you really goof it up. Several other systems-based consequences will appear in this area if they are relevant. If all is functioning well, the pane appears blank as shown above.
Using the status page, there should be no surprises to the user in any regard to the systems or weight/balance simulation.
Up next, using the buttons now visible at the bottom, you can navigate to the Performance Calculation page. This one is the one I am most excited for right now (though Triple Crew is pretty fun too!)
This performance calculation is very involved, this is no simple V1/VR/V2 lookup calculator.
This calculator is most akin to (and has been somewhat themed after) the program TOPCAT, well known by us serious simmers to give very accurate takeoff and landing performance calculation based on the same methods used in the real world.
You'll note that the calculator appears incomplete in the T/O profile section. This section has more to do with the triple crew part of this module, more on that later.
As shown above, the output window is currently blank. By default, on first load, the calculator has no flap setting selected. This is to ensure that the user doesn't nuisance-click the big CALCULATE button and then forget to change the performance information later. In fact, any time a change is made to any of the inputs at the left, or any time the actual weight of the aircraft in the sim suddenly changes by more than 2000 lbs (such as the user changing payload settings), the output window blanks! Safety, safety, safety.
Once all the other inputs have been modified and a flap setting chosen, clicking calculate will present you with the appropriate information relevant to your takeoff. As an example, here is the calculator using real world weather inputs for a runway 25 takeoff at KDEN:
There's a lot of information, but none of it should seem unfamiliar to a seasoned 742 driver!
A stabilizer trim setting (including corresponding green band switch setting), input OAT, the limit weight and limiting category for said weight, correctly adjusted V1, VR, and V2, and the EPR setting are all correctly calculated for any given set of inputs. These figures are based on corrected runway, takeoff, accelerate-stop distances, and pack config corrections directly from the 747 AFM for the 7R engine. At the bottom, the optimum climb speed for the selected takeoff weight is supplied.
You'll also note that all of this information is also supplied for a reduced thrust takeoff, if you so choose and if applicable. The limit weight for the reduced thrust takeoff is always either the current weight, or the minimum weight where V1 = VMCG, whichever is higher. The reduced thrust takeoffs also accurately adjust the V speeds when appropriate.
If you try to input information that results in a maximum takeoff weight that is less than the input takeoff weight, you will be greeted with a message:
You will also get a red alert if the takeoff runway is not sufficiently long enough to reach VMCG speed, if that is a limiting factor.
The speeds calculated by this calculator have been tested numerous times and so far, provided that you perform a rejected takeoff correctly and no later than V1, you will stop on the runway, every time. Of course, this is using my modified SIM1.DLL file the corrects the overly-high ground friction that exists by default in FS2004. Without this corrected file, your takeoff distances will be longer but braking distances will be shorter. My calculator will not be made to support the default ground friction, so for accurate results you should use my modified file.
You can switch between LBS and KG inputs if you want (which will also change the aircraft status page to the selected input), but by default the units that you have selected in your simulator will be what is chosen upon loading.
This functionality is repeated on the approach and landing page, but that is not complete enough to show yet...
You'll notice too, as mentioned earlier, the T/O Profile section which is incomplete (the runway condition section is also incomplete, as I am still implementing the corrections for wet runways, etc.)
This section has more to do with the Triple Crew part of this module, and the name should tell you everything you need to know about what it basically is. The real 742 is a triple crew aircraft, and managing all of the systems in busy phases of flight is daunting, hence why Boeing automated these functions on the 400 onward.
The T/O Profile section is your takeoff briefing to your virtual flight engineer: you will tell him the takeoff profile including when to switch to CLB thrust, what the acceleration height is in both all engines and engine out conditions, and he will faithfully follow your instructions during the takeoff climbout. He switches to CLB thrust for you, ensures the throttles come back to the correct setting, and manages reconfiguring the fuel and pneumatics systems all on his own, so that you can concentrate on flying the aircraft. The F/O will retract the gear and flaps for you during this time.
The flight engineer isn't only limited to takeoff and climbout, in fact he is active throughout the entire flight if enabled. He will accurately set the fuel configuration, change the packs over to half flow at cruise altitude, and lots of other functions that are all based on real automatic triggered flows at all phases of flight, allowing you to simply monitor him and concentrate on flying and checklists.
I am also currently working out if it is possible to get the virtual F/O to do holding patterns for you if you so desire.
And of course, using the triple crew menu, you will be able to enable or disable these crew members entirely, or disable only certain functions of them, all fully customizable to your preferred method of using them. Disable them completely for a challenging three-man experience! If you change your mind, simply re-enable them any time and they will automatically take over their duties without any complaints.
And finally...
Let's talk some flight model nonsense for a few moments.
If you're a real pilot or aerodynamicist, you'll know that most conventionally configured aircraft experience ground effect in a manner not quite accurate to what most simulators provide you.
Ground effect is much more than just an augmentation to your lift, there are also significant drag and pitch moment changes.
Unfortunately, I have not found out how to augment drag reliably with the tools I have without sacrificing functionality elsewhere, but pitching moment due to ground effect is something I can proudly say is accurately simulated in my flight model.
Now, if you're familiar with the FS2004 flight model, you must be scratching your head. The default flight model gives us developers no access to anything relating to change of pitch moment due to height over the ground, and you would be correct in that assertion! So how have I done this you ask? Well...
I briefly hijack your aircraft when the ground speed is over 100 knots and the aircraft is below 85 feet! Simple!
Joking aside, that is pretty much what I am doing. I have a gauge that is constantly writing to the stabilizer position when the above conditons are true. This gauge uses the real world data for pitching moment caused by ground effect for the 747 with appropriate adjustments for AoA and flap setting, converts that into a stabilizer trim position, and takes over the stabilizer from you during the takeoff roll and initial climbout, and during the landing flare and rollout.
The change in pitching moment at high AoA near the ground can be equivalent to several degrees of nose down trim, so needless to say, its big and important!
Once the above conditions are no longer true, the stabilizer will return to the setting that it was at initially before being taken over. During takeoff climbout, a ground effect multiplier based on current radio altitude is active, and will naturally reach zero by 85 feet, meaning the stabilizer will return naturally and correctly to the original setting during climbout. However, there is also a check that forces the stabilizer to its original setting no matter what once below 100 kts GS or above 85 feet, just in case a temporary lag spike or glitch should cause weirdness to occur.
And of course, because this is directly modifying the flight characteristics in ways that the user is not familiar with, the stabilizer gauge WILL show what is happening to your stabilizer, so you can watch it move in real time during ground effect if you want. And, just in case, there is an option to completely disable this function if you do not like it, however you will note that takeoff rotation and landing flare will be much more sensitive without this function enabled.
Alright... phew... that's everything for now! See you again soon for another update as we get closer to beta and release!
About the ''ground effect stabilizer'', is there an option to retain this function without seeing the stabilizer movement on the indicator?
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Thank you!
That would certainly be possible to do, I'll consider implementing it.
Just a friendly and curious question as to how it’s all progressing?