Position of elevators when the plane is parked

[Youtch]

Hello,

 

I understand that many of the older planes had their elevators actually dropping due to their own weight when the plane was parked, with the stick dropping forward as a consequence. Then upon switching on the engine, the propeller wash would raise the elevator into a centered position.

I understand that some planes have a bobweight to counterbalance the weight of the elevator, and hence the elevators are never dropping. I understand that more modern plane might have an hydraulic system to raise the elevator upon turning on the engines.

DCS needs to always align the elevators with the actual position of the stick, which is then usually centered as most of the sticks are with a spring-loaded base, hence not reflecting correctly the position of the elevators for a plane at cold start. 

But some Force Feedback Software such as TelemFFB for VPForce Rhino allows to simulate the elevator drop, which is a very cool effect, that left me wondering to which planes this elevator dropping effect actually applied.

Does anyone know if the elevator dropping applied to any post-ww2 planes implemented as a module DCS?

Parked F-14 seems to be with elevator dropped for instance.

 

Many thanks  in advance,

y.

[Youtch]

AI found the answer (although it seems it went very creative and did not check any pictures...

DCS Fighter Jet Elevator Droop Table

Aircraft	Elevator Droop (Engine OFF, No Hydraulics)	Elevator Droop (Engine ON, Idle Hydraulics)	Notes
F-4 Phantom II	Yes	No	Stabilators droop when hydraulic pressure is lost.
MiG-15bis	Yes	No	Early jet design; elevators droop when unpowered.
F-5E Tiger II	Yes	No	Stabilators drop when the engine is off.
F-86F Sabre	Yes	No	Elevator droops with no hydraulic pressure.
MiG-21bis	Yes	No	Hydraulics hold surfaces in position when running.
F-14 Tomcat	Yes	No	Stabilators droop significantly when powered down.
F-16C Viper	No	No	Electric actuator locks stabilizers in place.
F/A-18C Hornet	No	No	Fly-by-wire holds control surfaces at neutral.
A-10C II Tank Killer	No	No	Manual trim keeps elevators neutral.
M-2000C	No	No	FBW system locks surfaces in position.
AV-8B N/A Harrier II	No	No	FBW prevents droop at all times.
JF-17 Thunder	No	No	FBW controls surfaces even when engines are running.
MiG-19P Farmer	Yes	No	Old Soviet jet; typical droop when unpowered.
MiG-23MLA	Yes	No	Stabilators drop without hydraulic pressure.
F-15C Eagle	No	No	Electric actuators hold position.
Su-27 Flanker	Yes	No	Elevators droop when powered down.
Su-33 Flanker-D	Yes	No	Same as Su-27, droops when unpowered.
MiG-29 Fulcrum	Yes	No	Stabilators drop without hydraulic pressure.
J-11A	Yes	No	Same as Su-27, droops when unpowered.
AJS-37 Viggen	No	No	Hydraulic lock holds elevators in place.
C-101CC	Yes	No	Elevators droop slightly when parked unpowered.
L-39 Albatros	Yes	No	Common for older Soviet trainers.
MB-339	Yes	No	Stabilizer droop is typical of its design.
Mirage F1	Yes	No	Hydraulic pressure loss causes elevator droop.

Edited February 11 by Youtch
Correcting ChatGPT mistakes

[Dragon1-1]

Sorry, but that's bogus at first glance. "FBW controls surfaces even when engines are running?" Well, it does, but what does it have to do with anything that happens when the engine is not running? Have you verified that answer? Because I did a quick check, and it's wrong about AV-8B:
https://en.wikipedia.org/wiki/McDonnell_Douglas_AV-8B_Harrier_II#/media/File:US_Navy_030425-N-4008C-508_An_AV-8B_Harrier_aircraft_hovers_above_the_flight_deck_of_the_amphibious_assault_ship_USS_Bataan_(LHD_5).jpg

A whole row of Harriers that all refute the bot's BS. One clue that should probably tipped you off is that the Harrier does not have FBW. An equally basic check (just find any carrier pic with both on deck) shows that Hornets are also parked with their stabs tilted down, while Tomcats' stabs do not droop, presumably because they'd bonk into overswept wings if they did. A quick Google search of L-39 pics show that its stabs don't droop, either (in fact, one pic shows them deflected up, presumably they didn't bother to center trim before shutdown).

ChatGPT did not "find" the answer, it fed you convincing-sounding garbage and you believed it. Never use it as a source of information, because it does not give you information, it gives you a bunch of words arranged in a pattern based on a bunch of equations. That those words mean things does not enter into it.

[Czar66]

4 hours ago, Youtch said:

AI found the answer:

DCS Fighter Jet Elevator Droop Table

Aircraft	Elevator Droop (Engine OFF, No Hydraulics)	Elevator Droop (Engine ON, Idle Hydraulics)	Notes
F-4 Phantom II	Yes	No	Stabilators droop when hydraulic pressure is lost.
MiG-15bis	Yes	No	Early jet design; elevators droop when unpowered.
F-5E Tiger II	Yes	No	Stabilators drop when the engine is off.
F-86F Sabre	Yes	No	Elevator droops with no hydraulic pressure.
MiG-21bis	Yes	No	Hydraulics hold surfaces in position when running.
F-14 Tomcat	Yes	No	Stabilators droop significantly when powered down.
F-16C Viper	No	No	Electric actuator locks stabilizers in place.
F/A-18C Hornet	No	No	Fly-by-wire holds control surfaces at neutral.
A-10C II Tank Killer	No	No	Manual trim keeps elevators neutral.
M-2000C	No	No	FBW system locks surfaces in position.
AV-8B N/A Harrier II	No	No	FBW prevents droop at all times.
JF-17 Thunder	No	No	FBW controls surfaces even when engines are running.
MiG-19P Farmer	Yes	No	Old Soviet jet; typical droop when unpowered.
MiG-23MLA	Yes	No	Stabilators drop without hydraulic pressure.
F-15C Eagle	No	No	Electric actuators hold position.
Su-27 Flanker	Yes	No	Elevators droop when powered down.
Su-33 Flanker-D	Yes	No	Same as Su-27, droops when unpowered.
MiG-29 Fulcrum	Yes	No	Stabilators drop without hydraulic pressure.
J-11A	Yes	No	Same as Su-27, droops when unpowered.
AJS-37 Viggen	No	No	Hydraulic lock holds elevators in place.
C-101CC	Yes	No	Elevators droop slightly when parked unpowered.
L-39 Albatros	Yes	No	Common for older Soviet trainers.
MB-339	Yes	No	Stabilizer droop is typical of its design.
Mirage F1	Yes	No	Hydraulic pressure loss causes elevator droop.

First one is already wrong. Man people fully trusting in AI is scary as f&$#...

The Phantom II stabilators/elevators should droop because there is a counter weight on it, regardless of hydraulics. Airflow will balance against the weight with speed resulting in a more neutral position. But of course, any photo evidence can be dismissed by arguing the pilots are pushing the stick forward when taxiing. Only reading about its IRL systems of be in one yourself could serve as proof. Source: see the threads about FFB and how Heatblur coded the phantom controls. Or own the module and you'll see the stick going forwards by itself.

F-16s: It is not as straightforward as droop or not. Depends on other factors.

F-18s... AI got completely wrong. Their elevators should droop with no power. FBW has nothing to do with it.

Just don't trust AI with your life.

Mirage 2000Cs should droop too. As so it does in DCS:

Which crazy AI was that gave you these wrong answers?

Edited February 11 by Czar66

[Youtch]

First experience with Chat GPT, still learning here.

Many thanks for your answer! According to these pictures, most of the plane in DCS do have their elevators dropping

[Dragon1-1]

It would seem to so, but make sure to do research. There's no way that would be much easier than looking up pics of various aircraft parked on the runway. You need to do the legwork here, and no AI will help you with that.

16 hours ago, Czar66 said:

First one is already wrong. Man people fully trusting in AI is scary as f&$#...

The only thing we can do is come down hard on AI slop. Sadly, generated misinformation will only spread, because many people think AI is "smarter than any human". Those of us who know it doesn't even think will roll their eyes, but that requires knowledge. At least here, we have enough aviation enthusiasts and actual aviators who can call BS when ChatGPT pretends to "know" something about their favorite jet. 

Still, I guess we'll soon get people asking ED to make the Su-57 or some other highly classified jet, brandishing an AI-written flight manual and documentation, fully convinced that the "superhuman" AI had divined all the modern military secrets.  

[Youtch]

I have learned since my first day with ChatGPT yesterday to challenge it much more, and cross reference everything, which helps fine tuning information.

But fact is that it has access and can browse pilot manuals much faster than me.

Thanks for your feedback

 

 

Edited February 13 by Youtch

[Nodak]

Stick and elevator positioning coordination isn't logical since most of the modern jets flight controls aren't even directly connected, the stick sends requests to the servo's which do the actual movement of the controls to the position the CADC tells them they're permitted to move, even in many a non fly by wire.  Once power and pressure is off, the stick can still be moved, but it's not moving anything except itself.  Era of direct connect bell cranks, cables, and pulleys to a flight control is pretty much long gone, they connect either electrically or mechanically to a servo controller, or a computer controlling a servo controller. 

Pretty sure that's already modeled with power and pressure on in game, as for matching the stick to an control may want to limit that to the WWII stuff where it applies.  Even some of those aircraft came equipped with external crew placed control locks like the C-47's for both elevators and rudder for high wind conditions.

MB-339 comes equipped with a stick forward lock, and is in the locked position on cold starts.

[Youtch]

38 minutes ago, Nodak said:

Era of direct connect bell cranks, cables, and pulleys to a flight control is pretty much long gone, they connect either electrically or mechanically to a servo controller, or a computer controlling a servo controller. 

What about the F4?

[j9murphy]

This could be complicated by the fact that for some aircraft ( I think) the shutdown procedure has the pilot put the elevators down.  Dont know what that does to the stick in aircraft without a physical link, but it could be that the elevators are down and the stick is centered when parked? Probably easier to ask former pilots of each aircraft what the stick position is when the aircraft is not powered and if the elevators drop on their own or not.

Edited February 12 by j9murphy