McDonnell Douglas MD-11 Development

[merspieler]

If it's texture loading times, that's cause the fg code of the default way of switching liveries is so inefficient... loading the very same texture into a canvas is way quicker.
-> canvas livery system can relief that

[Octal450]

Yeah, I've looked at Canvas liveries but no time for that now. Maybe after CaptB's changes are done.

Kind Regards,
Josh

[merspieler]

I wouldn't recommend switching either to be honest... there are still a few bugs I need to fix (ie. MP)

[DaSovietPotato]

I was playing around with the aircraft and I was wondering how realistic the stall characteristics were. I am not sure if it has anything to do with how I am flying, but I noticed how hard it actually was to stall the plane when taking off. It just seems like the plane was too powerful to stall in any normal way. In the process I also noticed the wing flex, nice touch .

[Octal450]

@DaSovietPotato

You sure you used the version from my repo and NOT the launcher version?

While not perfect, the stall characteristics are pretty close to correct.

Kind Regards,
Josh

[DaSovietPotato]

I am using the repo version, and as far as I know it is fully up to date. It seems that two things are happening.
1. The controls can't change the pitch fast enough to completely stall.
2. The engines retain full power despite the complete lack of forward moving air to keep the aircraft from moving slow enough to stall.
TBH the issue is somewhat moot because of the flight director, but it just came to my mind to ask about the stall characteristics.

[Octal450]

Hi:
1) LSAS will try *really* hard to stop you from stalling. You have roughly 20 degrees of elevator, and the LSAS system has 5. So if you pull full aft, and are in the LSAS stall protection active, LSAS will give downward 5 degrees meaning you only get about 15 degrees upward deflection.

Furthermore the elevator feel system may reduce the deflection a little more, and lastly the MD-11 has a very small tail for fuel efficiency, so as you approach the wing stall area, the elevator loses its effectiveness very quickly, this is one of the reasons for the LSAS system to exist to modulate the elevator's movement to sharpen up the response during normal flight (and provide some basic pitch attitude hold/damping - similar to an Airbus but not as precise)

So naturally the system will try really hard to anti-stall you, making an attempted stall not very easy

2) If you want to throttle back, you will need to turn the AFDS OVRD's on, to prevent the ATS Speed Protection from maxing out the power to the thrust limit in an attempt to prevent underspeed.

Hopefully I understood what you meant correctly. There is room for improvement in the stall behavior, something I plan to address further later.

I really appreciate your feedback btw!

Kind Regards,
Josh

[naplesAPF]

Found Down load page

https://sourceforge.net/p/flightgear/fg ... rcraft/777

[Octal450]

Wrong thread
Josh

[Octal450]

Added Slat Stow function



Kind Regards,
Josh

[Octal450]

Fixed the first officer's yoke being inverted... I forgot a minus sign when I refactored the code. Thanks SymbolicSam for reporting this, I missed it somehow but he noticed!

Sorry guys!

Kind Regards,
Josh

[Octal450]

Improved stab trim simulation
- when over 250kts or above 33000ft, the trim speed is reduced
- you can now override LSAS's trim even during PAH law, however LSAS will go back to trimming to fair the elevator shortly after you stop overriding. This means you can now use your trim switches to trim faster if LSAS is not trimming quick enough for you
- PRD law no longer causes autotrim commands (this was incorrect)

Now when you cross 26000 in the climb, IAS automatically changes to mach
- if you had a mach preselected, that value will be used. otherwise, it will use the current mach
- same logic for back to IAS descending through 26600
- Note: if it switches over to mach, and you switch back to IAS, it will NOT go back to mach automatically unless you descend through 26000 and then climb up again through 26000, same is true for mach to IAS.

Kind Regards,
Josh

[Octal450]

Deploying the spoilers now causes an upwards pitching moment, LSAS and AP will of course help you not notice it.
You will notice when spoilers are deployed and AP on, the yoke will be nudged forward and then back when retracting.

This also means the LSAS's downward deflection on spoiler deployed during landing actually has a purpose now.

Kind Regards,
Josh

[Octal450]

I have added/simulated RCWS
This time properly, unlike the wrong way I did it years ago
When enabled, the yoke commands a roll rate and the inner aileron is controlled to keep it, this backdrives the other ailerons and spoiler thru the cables.

RCWS will also fight banks over 30 degrees similar to how the Airbus does, but there is no hard limit. A determined pilot can overbank.

RCWS is optional because most airlines de-activated it.
FedEx, UPS for example, fly with RCWS turned off.

There are still a few little details to simulate like the yoke kick interaction with drooped ailerons and RCWS, and some tweaking in the response, which will be done shortly.

Kind Regards,
Josh

[Octal450]

Added the yoke kick anomaly

it means, when RCWS AND Drooping Ailerons are equipped, the active RCWS inner aileron (left for FCC 1, right for FCC 2) is driven downwards to droop via the electronic FCC actuator, not the Aileron Deflection Actuator, and the FCC is ever slightly slower at driving the aileron. This causes the system to backdrive the yoke about 12 degrees for about a second. The effect on airplane stability and controllability is negligible since in either RCWS or Autopilot mode, the roll rate is held by the system. The direction of the yoke deflection depends on which FCC is active, and whether the drooped ailerons are deploying or retracting. It does not occur when deploying flaps for landing as the ailerons do not droop.

You can read more about it here: https://www.pprune.org/tech-log/229706- ... ost2647968

Kind Regards,
Josh