Reverse Thrust

[bstolle]

Quote:'It COULD effect handling'. A strong wind could do the same.
And don't cite real dyanmic parameters to 'apply' in flight simulator. It just don't work that way

Don't know where your weird aggressiveness comes from but:

A strong wind affects handling???? The plane doesn't care at all if its flying straight and level with 0kts wind or 50kts wind.
Of course real flight dynamics work in FSX, you just can't simply use real world numbers.

BTW:
1. A too far aft CG will reduce pitch stability (like IRL)
2. A too far forward CG can prevent you from stalling the plane due to too little elevator power (also like IRL)

 

[napamule]

Acertiveness

bstolle,
I am not agressive in any way. This is 'shop talk'. If you are not scientifically adept (ie: aeronautical engineer or mechanically inclined) then don't INVENT stuff. I am sorry, but you are using terminology that is not scientific. It's also vague. What is 'too far' for 'aft CofG' (did not know there was a SET reference position for CofG). By sheer OBSERVATION you can determine, and I am sure you will agree, that ALL models (default and 3rd party) are all DIFFERENT when it comes to CofG. It's never at the same point as the other aircraft. If you don't agree then I contend you don't have enough FDEs experience. Either you know it, or you don't. There is no guessing.

You say 'too far' 'aft CofG' will 'reduce pitch stability'. What does THAT mean? You can't pull up? Or you can't nose dive? Or the aircraft will not stay level? If it's the latter then you need to learn to use elevator pitch trim, as IRL.

Then you say 'too far' 'forward CofG' will prevent stalling due to 'elevator power'? What elevator power? If you cut throttle and pull nose up it will stall when it reaches a certain speed. So you don't have enough elevator area? Your elevator up/down limit(s) are not right? Your controls elevator axis is not calibrated? Your (flight tuning) entry for pitch stability is =5.0? It don't make any sense to blame ONLY the CofG. That's not scientific. Or true. Why? Because a lot of cfg entries are WRONG and no one is the wiser. It's 'tradition' to let some 'nube' (or program) do the 'brain work' for you and then you just accept it without any question. Not scientific.

You say a 'strong wind'. (I said a 5 kt wind will prevent you from backing into the wind if you are using reverse thrust and you only adjust (1). 'prop_reverse_available= 1' and (2). 'min_throttle_limit= -0.35'. Please define 'strong wind' and whether you can move backward against it using reverse thrust. And if not, what would you adust to remedy this. This is the original theme of thread, you know. Setting CofG to '=1.000, 0.000, 0.000' will NOT cause/lead to 'too little elevator power' (?) or 'reduce pitch stability' (?). Bogus.
Chuck B
Napamule

 

[bstolle]

1. If you are not scientifically adept (ie: aeronautical engineer or mechanically inclined) then don't INVENT stuff. I am sorry, but you are using terminology that is not scientific.
2. You say 'too far' 'aft CofG' will 'reduce pitch stability'. What does THAT mean? You can't pull up? Or you can't nose dive? Or the aircraft will not stay level? If it's the latter then you need to learn to use elevator pitch trim, as IRL.
3. If you cut throttle and pull nose up it will stall when it reaches a certain speed.

1. ROFL
2. As you apparently don't even know what reduced pitch stability means, this discussion is totally useless.
3. wrong

Have a nice day

 

[napamule]

Re-Hash

bs,
Quote: 'Please define 'strong wind' and whether you can move backward against it using reverse thrust. And if not, what would you adust to remedy this. This is the original theme of thread..'

About 'reduced pitch stability' (whatever this means), will this do?
Longitudinal static stability is the stability of an aircraft in the longitudinal, or pitching, plane under steady-flight conditions. This characteristic is important in determining whether a human pilot will be able to control the aircraft in the longitudinal plane without requiring excessive attention or excessive strength.

A mathematical analysis of the longitudinal static stability of a complete aircraft (including horizontal stabilizer) yields the position of center of gravity at which stability is neutral. This position is called the neutral point. (The larger the area of the horizontal stabilizer, and the greater the moment arm of the horizontal stabilizer about the
aerodynamic center, the further aft is the neutral point.) The static center of gravity margin (c.g. margin) or static margin is the distance between the center of gravity (or mass) and the neutral point. It is usually quoted as a percentage of the Mean Aerodynamic Chord. The center of gravity must lie ahead of the neutral point for positive stability (positive static margin). If the center of gravity is behind the neutral point, the aircraft is longitudinally unstable (the static margin is negative), and active inputs to the control surfaces are required to maintain stable flight.

Some combat aircraft that are controlled by fly-by-wire systems are designed to be longitudinally unstable so they will be highly maneuverable. Ultimately, the position of the center of gravity relative to the neutral point determines the stability, control forces, and controllability of the vehicle.

Quote: 'this discussion is totally useless'. I say I need to know if your ac will move backwards into a wind of 5 kts in FSX by using reverse thrust, and if not, what adjustment(s) would YOU make to aircraft cfg or air files? Help me out here. Forget the attitude.

And: To repeat: Moving the CofG 'forward by 1 foot' will not 'ruin' your dynamics (handling or stability) but IN FACT it will INCREASE your 'stability'. I hope you don't continue to argue against the facts on this point. But it's the reverse thrust question that needs answering. Anytime this week is 'ok'.
Chuck B
Napamule

 

[mal998]

"Could 'a Would 'a

Quote:'It COULD effect handling'. A strong wind could do the same. What I suspect 'happened' is that you inherited a set of lousy FDE's and ANY change anywhere COULD (of course) be 'blamed' for ruining the handling. It's just so easy to ASSUME things are a certain way, and set in concrete, because 'that's the way it's always been...'. Or, was 'made up' to apease the crowds. Like the nose up attitude. The horiz stab incidense does more to effect THAT than the CofG ever (EVER!!) will. But I am talking to the hand I imagine. Cheesh.

This is why I hate to discuss flight dynamics because there is always one or two that will argue all day about something that does not apply to flight simulator at all (although it DOES apply to 'real' flying). 1 ft change to CofG does NOT ruin your handling IN FLIGHT SIMULATOR. A bad set of FDEs (dynamics) WILL ruin your handling. Don't mix them up. And don't cite real dyanmic parameters to 'apply' in flight simulator. It just don't work that way. Flt Sim is DIFFERENT to real. Even flying ac in sim is different. OK? OK! So don't change anything. Leave your FDEs the way they are. Fly like you alway fly. Rely on the modeler to provide you with instructions ('how to fly') in the 'ReadMe' txt file. Right? Right. And ck the various forums for 'no reverse thrust', 'bounce on landing', 'shaking sitting on runway', 'tip over on tail on brake when in reverse', 'airplane won't turn on taxi', etc, etc. It's all there. Over and over. Same ole questions. Again and again. Something has GOT to change, I do believe. But, minds are hard to change. That I know.
Chuck
Napamule"


Chuck, Chuck, Chuck,

I never said anything COG "ruining" handling. I said it may affect the attitude of the aircraft while in flight. Oh and BTW, I already answered the question to which the original poster responded by saying "That's the perfect solution !!! Thanx a lot for that one. Every other mentioned solutions has the serious drawback of screwing up Ng, Np or boththanks it works"

And to be clear, I don't inherit things, I build them. You can try out my latest macinations when you fly Virtavia's new F-111. That would be my flight dynamics that you'll be enjoying, as I did the files for that little beauty.

But, you're the expert here so I'll leave you to your strongly held point of view, napa-mule.

 

[napamule]

I Get It

You wanted to promote your Virtavia F-111. Ok, fair enough. But since I don't buy (or ever intend to) any add ons I will never 'enjoy' your 'creation' (yeah right).

Send me the model and I will run it through my hanger and fly it and give you feedback. I want to know what 'PERFECT' FDEs (according to you) look like. (And from Virtavia, no less-go figure).
Chuck B
Napamule
'Napamule' means 'Napa Auto Parts' delivery driver (or 'mule'). My last job before I retired. I wouldn't make fun of your 'handle'. Your face, maybe. But not your username.

 

[Rich]

Sorry would someone who has the ability please put the clampers on this thread it gets so boring when the great I am keeps sticking his oar in.

 

[Moparmike]

Well guys,

The OP has found a solution to his problem and offered thanks. After that, a lively discussion on flight dynamics in real-world and FSX (yes, they can intermingle). And lastly, the name-calling has begun...

That means it's time to shut it down and move on to other things.