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pacosancas

ATR 42-300 question

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Hi ,I use a little reverse thrust once i am moving ,this works fine for meAnniette xxxxxxxxx

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I will try that. Thanks for the tip and the BA repaint, Anniette!

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Excessive Speed (ala Beech 350) and cornering is a problem. I have installed the Version 2 *.air file and the updated aircraft.cfg (really helped) file. Trying to stay within some reasonable speed to make turns is difficult. I have tried to use F11/F12 (differential braking) with poor results. It seems the front tires are slipping across the pavement vice turning even at very slow speeds.I know Paco has worked hard on this model and made some trade-offs. I don't know if poor ground handling is part of the trade-offs due to COG and weight and balance.Since I really like his ATR42-300, I'll keeping flying it.

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Hi,First, make sure the idle gate is on ground idle position; FS leaves it on flight idle when you start with ctrl+E, and that gives much more throttle than desired.Still the plane will have a noticeable amount of thrust with both engines running, more than enough for taxiing. The real plane also suffers from this, and it is not unusual to start taxiing with only one engine runing, and then start the other one before taking the ruway.If you have the oportunity to see a real 42-300 at your local airport, you will notice if it starts taxiing with both engines running, that it will literally jump forward as soon as brakes are released, with no need to apply throttle. This is what I tried to simulate. If you don't like it, there is a way, if you have aired.exe, open the .air file and go to record #1503. Reduce all values in the first column, this will give less thottle at ground idle.The difficulty in steering may appear if you apply full pedal to either side, as this will only work at almost zero speed adn with the aid of differential brakes. This it because of the large steering angle, 85 degrees to either side. It is advisable not to apply full steering while taxiing, but only half steering angle. If you still dislike it, this can be changed in the following line in the aircraft.cfg file:point.0=1.000, 35.000, 0.000, -13.6000, 1574.803, 0.100, 0.518, 85.0, 0.2500, 1.500, 0.900, 8.000, 8.000, 0.000, 0.000, 0.000Just change the value 85.0 for a smaller figure. The problem will then be that you wont be able to perform 180degrees turns in runways less than 200m wide! ;-)Paco

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Thanks for the info, Paco! I think I'm going to have to sacrifice a little realism for I-can't-flyability and lower the ground idle.

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The typical way of controlling your taxi speed in a typical turboprop in real life is to make use of the beta position of your power levers, with the prop at full forward rpm, and the condition levers at ground idle. In beta, the props move fully flat, on their way towards the reverse position, nullifying any thrust. To simulate this in MSFS, go into just a little bit of reverse thrust as you taxi around and feel like you need to slow down. This is why when you hear a turboprop taxi in real life, the noise pitch will often change suddenly and briefly for no apparent reason.

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Paco,What does the Idle Gate do? Is it engine speed or prop RPM. I think the C-130/P-3 have a Low/High Range setting but I think it was gearbox changing.I changed the nose wheel steering angle to 35deg max. It seems to work better for me, since I use the joystick twist grip.Differential braking using the F11/F12 doesn't seem to work well for any aircraft. I suspect it is either totally ON or totally OFF, not just a slight brake pressure where the braked wheel keeps turning but slower.

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One thing I noticed with this aircraft, while using it exclusively as AI, is that the weight and balance is configured in a way that the entire weight lies at one specific point in the datum plane (original file). In other words, it all balances at one point. A fix for this is to move the weight on the lateral plane up one foot. This will make just enough shift to keep the nose from "poping up" while taxing at higher speeds.Serb

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Hi,The idle gate (in real life) sets the lower limit that the power levers will go. It has two positions, ground idle (the levers are allowed to go all the way down) and flight idle (the levers are stopped from going all the way down, which results on a higher turbine rpm -and therefore a higher torque- at idle). In the FS model, the levers will visually move the same, but the effect on the turbine rpm will be as described (FS does not have a separate variable for the idle gate, so I had to program its function into the trottle levers gauge). The default King Air does not have a separate idle gate lever, but has the same functionality in the condition levers; they have three positions: fuel shutoff, low idle and high idle.So basically it does not alter Propeller rpm (well, at slow speed in the FS model it does, as a side effect), but rather the gas producer (turbine) rpm. I am not familiar with the c-130, but my guess is that the high/low setting can be two things: either the idle gate as described, or the condition/propeller levers with two positions for the propeller rpm's. (remember, the prop levers on a constant rpm propeller do change the rpm at which the propeller rotate, not changing gear -such thing cannot be done on an aircraft-, but rather varying the blade angle -beta-. The effect is similar as shifting gears on a car.)Paco

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Paco,Thanks for the reply. I flew a flight from KMCO to KJAX last evening (I don't know why some complain about the lightening, the real weather here yesterday had lightening storms in the area and it sounded and looked pretty real). I followed your checklist to a "T". Works great but the margin around the Torque indication and the Warning Light seems tight (I think you mentioned this earlier).The only area of the checklist that confused me was on Pre Landing, where you say to place the Idle Gate to Ground Idle position. From your description above, this will NOT reduce the set engine torque during this phase when you move the Idle Gate from Flight Idle to Ground Idle but will allow a lower idle setting once you have brought the Throttles to idle after landing. Am I correct?Following the checklist on taxiing with the Idle Gate in Ground Idle and restricting the nose gear to 35deg, really improved my taxiing ability.Lastly, I had a very enjoyable flight, only problem was an AI cut in from of me on final and I knew he wouldn't clear the runway before I would get to the runway, so I initiated a 90/270 and the ATR42 responded wonderfully. Came around and tower cleared me No. 1 for landing.Thanks again for a great aircraft!!

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Hi again,I must do a check with the source for my checklist, as I do not remember now if in the real plane the idle gate is set to ground idle before or after touchdown. I guess it might be before, as the flight idle position shouldn't allow the levers to go into reverse.But in any case, if you have a certain torque, say 15%, putting the idle gate into ground position will not reduce this torque. The difference is only when the levers are put all way down to idle position, which in flight will always mean 0% torque. Your interpretation is correct as far as I know. Paco

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