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jcmmg
05-04-2010, 07:51 AM
Hi all

I got some thoughts and rhetorical questions about it, hope someone can answer!


In real life the way to control the steering of a plane (GA) is to use differential brakes or throttle (multiengine) to control the steering, as the nosewheel behaves like a supermarket trolley wheel, it is free!

Does someone know if there are an utility, fix, edit, etc to improve the ground handling of every aircraft in FSX? It is possible to be created?

Or could be possible if the Realair feature "nosewheel free castoring" of the Duke, can be added to other planes?

This feature will be excellent in all planes as improves dramatically the ground steering making it realistic and particularly helpful for crosswind landings!

Clear skies and free glitches!

Jcmmg

pggppg
05-04-2010, 08:31 AM
It depends what you are flying - certainly some Airliners are controlled at low speeds using nose wheel steering and differential braking, assisted by differential thrust. To my knowledge there are certainly some (I won't put my head on a block by saying all) aircraft that have true nose wheel steering which is accomplished by hydraulically steering the nose landing gear which is by either a tiller in the cockpit or the rudder pedals though I believe rudder pedals give only a few degrees turn. I also think I read on a spec sheet that the nose wheel steering is disconnected by retraction of the landing gear so that it fits correctly in the wheel bay and stays put.

Some are electrical and some are mechanical but I know not which planes are which.

I hope this helps.

ladamson
05-04-2010, 09:43 AM
My real life airplane has a castoring nosewheel, which uses differential brakes until the rudder kicks in. The rudder is somewhat effective at higher taxi speeds. However, lot's of GA aircraft do use a nosewheel connected to the rudder pedals. And larger aircraft may use the tiller as mentioned in the other reply. On the other hand, WWII bombers such as the B-29 & B-25 used a castoring nosewheel.

With all the variables, when it comes to flight simulation, I don't worry about it. I'll use my rudder pedals, and if the turn radius isn't enouigh, then I'll use differential brake keys. I don't have multiple throttles for the use of engine turning.

L.Adamson

Anubis
05-04-2010, 04:16 PM
The Alphasim Rutan Long-EZ has the option to use a castoring nosewheel, it can be switched on (steering with differential brakes) or off (steering with the rudder) by a simple change in aircraft.cfg.

Paolo

simonevans
05-04-2010, 07:40 PM
Hi all

I got some thoughts and rhetorical questions about it, hope someone can answer!


In real life the way to control the steering of a plane (GA) is to use differential brakes or throttle (multiengine) to control the steering, as the nosewheel behaves like a supermarket trolley wheel, it is free!

Does someone know if there are an utility, fix, edit, etc to improve the ground handling of every aircraft in FSX? It is possible to be created?

Or could be possible if the Realair feature "nosewheel free castoring" of the Duke, can be added to other planes?

This feature will be excellent in all planes as improves dramatically the ground steering making it realistic and particularly helpful for crosswind landings!

Clear skies and free glitches!

Jcmmg

A sweeping generalisation which is simply not true. Others have answered for the nosewheel steering, but having a castoring nosewheel does NOT improve crosswind handling - not in real life and DEFINITELY not in the sim! :eek:

ladamson
05-04-2010, 09:11 PM
A sweeping generalisation which is simply not true. Others have answered for the nosewheel steering, but having a castoring nosewheel does NOT improve crosswind handling - not in real life and DEFINITELY not in the sim! :eek:

Was going too, and didn't get around to it....

Yep, can't think of any condition where my castoring nosewheel/ differential brakes improves the crosswind landing. At the most, you might tap a brake on the takeoff roll.

L.Adamson

ScatterbrainKid
05-05-2010, 12:45 AM
I've yet to see an aircraft in FSX (and FS2004 for that matter) that handles properly on the ground; it's as if the ground is an ice rink and you slip and slide all over the place during takeoff/landings because the tyres have no 'bite', it's a Major Flaw that the programmers never bothered fixing.

napamule2
05-05-2010, 08:39 AM
Well FINALLY someone hit the nail on the head. FINALLY someone has made a TRUE statement in that the 'Programmers' (ie: modelers) don't know and probably don't care if the a/c ground handling is proper. It is evident, if you know what to look for. The problem is in the wheel position, or placement, in the (Contact Points) section. But most modelers wouldn't EVEN know what to do, so it's no use asking them to fix it. Not won't-CAN'T.

If you have the nose wheel too far forward, or too far back, and mains too far back, you WILL ruin the ground handling. And all the positioning of ACTUAL contact points will be different for different models and will ALSO depend on the 'reference_datum_position', and the 'empty_weight_CG_position' values. What they 'give' you is not always right.

Hard to fix? Not if you know what to do and you have the model to test out the changes (with a little 'trial & error' tweaking). The contact points is the FIRST thing I look at and fix on EVERY a/c I install. No other way. Bob Chicilo keeps mighty busy with just this one (ignored) FACT and he never gets any praise, credit and/or respect.

Oh yeah, it LOOKS good, but it handles like heck. But, you got it at a good price (free). Right? Not good enough. If you are 'in the business' you should know all about it-not just what is 'fun'. Rant? No-this is my pet peeve-2nd rate 'work' and sloppy cfgs by modelers.
CB
Napamule
CB
Napamule

jcmmg
05-11-2010, 05:31 AM
Thanks everyone for your answers!

I first started this threat as part of my testing to know how FSX aircraft behaves under strong cross wind environment, particularly after seeing the improvements of paywares, I wanted to see if this enhancement includes ground handling.
I started by setting the weather: winds 278/24 kts, location EGPO, broken clouds at 10000 ft, temperature ISA, and the departure runway 18.

Then I have performed some taxi manoeuvres and a standard circuit landing, with 5 default planes (GA and military) and 8 pay addons (GA and military). Notice that I didn't use commercial airplanes or big irons.

I started by thinking as I stated in this threat that having a "nosewheel free castoring" will be better than the common option (linked to the rudder) and of course payware Vs default.

My findings were not very different to the general knowledge but here they are:

- Low speed taxi (less than 30 kts indicated) Rwy 18: "nosewheel free castoring" behaves slightly better than the other case.

- High speed taxi (more than 30 and less than 45) Rwy 18: The wind starts to affect all airplanes handling, some behave better than other, it doesn't matter if they are payware or not. "nosewheel free castoring" are good, but the best handling was for military planes.

-Takeoff: The skating sensation was stronger, some payware are much better. But I could control all of them. Keep in mind that you have to apply strong rudder in order to keep align to the runway, but in the wind direction, other words downwind (is this real?)

-Landing: 1 out of 13 I ended crashing the plane (default DC-3) for me was the worst, very difficult to control after the touch down!!! 2/13 I have to perform a "go around" manoeuvre with 2 military planes. All GA landed safety and within the first third of the runway. I strongly advise that you must change the rudder direction as the touchdown is imminent, from upwind in the air to downwind as you touch down, otherwise you could end by going out of the runway since the plane will have the tendency to move upwind! In some planes you have to do it with a strong force even braking with the downwind wheel.

At the end I got mixture results, being the military planes (payware and default) the best controllable, but keep in mind that they are unstable in the ground so very small and balance braking need to be taken in order to keep them align and in the centre of the runway. I think this result is because they have stronger brakes...

Some payware are better than default some not, I don't have the proper methodology to judge them and I was concentrate more in the skating behaviour on FSX. In order to do so I think more than one touch and go will be needed in order to evaluate them properly

Hope this will guide new simpilots and could have some words about the ground handling that it is important to take into consideration by programmers!

Any comments feel free to contact me

Best wishes to all!

Julio

jcmmg
05-11-2010, 05:56 AM
The list:

Default:
Ultralight Trike
Cessna C172
Beech Baron BE-58
Boeing F-18 Hornet
Douglas DC-3

Payware:
Carenado Cessna C-172N
Carenado Mooney
IRIS Diamond DA-42
Just Flight Cessna C-152
Realair Duke
Flight1 Cessna Citation Mustang
Aerosoft F-16
VRS F-18E

simonevans
05-11-2010, 10:02 AM
Most of the nosewheel-wandering tendency is solved (in nosewheel aircraft, obviously) by the simple expedient of applying some DOWN elevator when taxiing or beginning the t/o run. This is particularly beneficial with the default aircraft.

For taildraggers the results of applying UP elevator can be mixed. Which is symptomatic of the individualistic nature of tailwheels, and precisely why nosewheels are more common in the modern age.

Finally, in all cases your criterion are incomplete UNLESS you also state the loadout configuration and fuel load of the aircraft in question: All aircraft vary in ground response depending on the CG location. FSX exaggerates this effect.

ladamson
05-11-2010, 11:41 AM
-Takeoff: The skating sensation was stronger, some payware are much better. But I could control all of them. Keep in mind that you have to apply strong rudder in order to keep align to the runway, but in the wind direction, other words downwind (is this real?)

For takeoff in a crosswind, I'll roll the stick/yoke fully into the wind at the start of the takeoff roll, but use rudder to remain tracking straight down the runway. My main concern with rudder is the ability to remain on the runway. As airspeed picks up, then just start rolling the aileron back towards neutral.



-Landing: 1 out of 13 I ended crashing the plane (default DC-3) for me was the worst, very difficult to control after the touch down!!! 2/13 I have to perform a "go around" manoeuvre with 2 military planes. All GA landed safety and within the first third of the runway. I strongly advise that you must change the rudder direction as the touchdown is imminent, from upwind in the air to downwind as you touch down, otherwise you could end by going out of the runway since the plane will have the tendency to move upwind! In some planes you have to do it with a strong force even braking with the downwind wheel.

Use aileron to center the plane on the runway, even if the nose is crabbed in the direction of the wind. Then use the rudder to align the nose to the landing direction............to avoid side loads on the gear. If there is not enough rudder, then land somewhere else, that's more aligned with the wind.

Notes: In a strong crosswind, I can elect to start the takeoff from the opposite side of the runway if desired. Same for landing. Some aircraft have landing gear that are capable of landing while crabbed, as they can rotate sideways. There are several methods of landing........ kick the nose straight at the last second, or cross control (wheel low --slip) on the final descent. I prefer kick at the last second. I tend not to use brakes for the landing until slowed sufficiently. How much aileron I'll actually use in the crosswind takeoff varies with conditions.

L.Adamson

jcmmg
05-12-2010, 05:33 AM
Finally, in all cases your criterion are incomplete UNLESS you also state the loadout configuration and fuel load of the aircraft in question: All aircraft vary in ground response depending on the CG location. FSX exaggerates this effect.

Not only that, I also don't have the same amount of hours on each aircraft hence I can't judge each plane nor compare default Vs payware.

My point was to have a look on crosswind simulation in FSX using standard control management, yes I can choose other runway or airport in the event of extreme cross wind, but this was an experiment. I started this threat by indicating that "nosewheel free castoring" was better, which prove not to be true.

Also if you use real weather, you will hardly find 25 kts of pure cross wind component (Well I have around 600 hours in FSX and never find it)

I learned new techniques and will apply them to see the results!

Well guys thanks a lot for all your participation; I am really glad with outcome, very interesting feedback and plenty of new knowledge!!

I really like being part of Flightsim Forum

Clear skies!

Jcmmg