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Guest Dann

Reality Check

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There is no doubt Flight Unlimited III provides a fairly realistic feeling as far as flying general aviation aircraft is concerned.However, there are some places the game skips reality and favors playability; make no mistake, these do NOT affect the experience at all.Most every prop-driven aircraft in the sim (except the Cessna 172) requires gently reducing power at the risk of cracked heads. For instance, the Mooney requires about a 1" of manifold pressure per minute reduction, and the DC-3 about 1" of manifold pressure per 1,000 ft. with a prop rpm reduction coinciding or the propellors will drive the engine, starving the main bearings of oil.So, my question, in the form of a Yes or No poll: Does anyone here fly these aircraft this realistically?Me: No. It would limit the fun I would have buzzing airports and buildings.Dan

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I'm trying to fly them realistically but I will throttle down too fast if required. The better approach (literally speaking) is to plan ahead and get the gear down if you need to sink faster. Then one may add a couple of notches of flaps, retrim and come in nicely without having to shock-cool the engines by going idle. I prefer gear down and flaps to spoiler / air brake for slowing down and all planes can be slowed down nicely if one uses the "natural parasite drag" to ones advantage. But by all means, don't slow down by extending the flaps! Rather, lower the gear as your first step, retrim and lose speed and then extend flaps. At first there'll be a little ballooning but it soon settles at a lower speed. Then retrim and go more flaps if required. The gear can take much more abuse in terms of wind pressure than the flaps can. Plan to get into the landing configuration in due time and there'll be no need to kill the power suddenly to slow down.This wasn't exactly the "yes or no" answer you requested :-hah Hans Petter

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No. I do not fly them realistically :)The exception would be the Mooney because it's so darn expensive I don't want to break it.Just a ?If you reduce power, you say you also should reduce the prop RPM. However, in most checklists I've seen, the final approach should be done with prop RPM at full? Or am I wrong?

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RPM full is just one of those last check list items you'll do before landing. The whole idea is to have "fine" pitch for the most usuable power should a "go around" occur. In reality you may also be playing with pitch to control speeds (like an airbrake) when close to landing or in the pattern inviroment.L.Adamson

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I just noticed this as I re-read Dann's post:"-and the DC-3 about 1" of manifold pressure per 1,000 ft. with a prop rpm reduction coinciding or the propellors will drive the engine, starving the main bearings of oil".Propellers driving the engines = windmilling. I know that it's being taken advantage of in slowing down some aircraft -- are you saying that it's bad for all piston engines? Windmilling definitely is bad in an "engine out situation" since the dead engine isn't just ceasing to provide any power -- it's causing a lot of drag. The prop lever or the feathering ought to be set at "full feather" if an engine quits to minimize dead engine drag.Hans Petter

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Yes, I try to fly as realistically as possible.No, I don't always succeed! There's nothing as rewarding as a well-planned, smooth landing however it sometimes doesn't work out that way. Many is the time I hit just before I plough into an object - I don't believe in practising crashes! If I TRY being sloppy, I get bored and give up. The other thing is, if realism was the key, I wouldn't fly in half the weather I do!So, no, not really.Jon Point*************************(effyouthree@hotmail.com)*************************

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My curiosity is the statement of "starving the main bearings of oil". Not sure of the oil pump process in the radial engines of the DC-3, but I figure the oil pump would be running off a gear from the crankshaft. Depending on the crankshaft RPM, the oil pumped should vary accordingly. I don't see why windmilling would make a difference in the oil supply. If someone knows a reason......... then let me know!L.Adamson

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Hey all,Thanks for the replies! (It was 33 views and no responses, I thought the question might have been too hard!)Regarding prop speed and landing: YES, you advance the prop controls to max for the landing, in case of a go around.HOWEVER, after downloading and flying the wonderful DC-3, I did some research and found some information on checklists and flying. For whatever reason, the DC-3's engines, when windmilling excessively, can starve the main bearings of oil. Remember, this is 1930's technology we're talking about. Here is the entire excerpt:Rob Campbell (DC-3 pilot) says.... "One other 'thing' about the procedures in regard to using power. We NEVER reduce the MP below the RPM until the final reduction as the landing is assured. To reduce the power earlier invites the propeller to drive the engine and starve the main bearings of oil - this regardless of the speed of the aircraft - but especially if the speed is higher. If there is any question about this, the next time you fly, put the props full forward on downwind or at the outer marker, hold 100 kts and pull the power off to get down - you can actually hear the lugging of the engines. Proper use of the flaps w/ a MP setting no lower than the RPM will allow for a very nice descent rate."More from the same source...Most round engine drivers and those who have a great interest in the old birds have heard the term "backlash" or "backloading". It refers to the prop driving the engine. This can occur in a descent at low power settings. When the prop drives the engine, all the forces on the bearings and gearbox are reversed, and this is what causes the damage. The bearing surfaces and the gearbox are not designed for these opposite pressures.So...to keep the engine driving the prop, here are some airspeed guidelines. Above 140 kts. IAS...keep at least a 5" spread (ex. 2150 rpm / 26.5" map); 100 to 140 kts., at least square (ex. 2150 rpm / 21.5" map). Manifold pressure should not be allowed to go below the corresponding rpm until the airspeed is below 100 kts.Another guideline on power reduction is no more than 2 inches every 2 minutes. This assures gradual cooling.On landing the DC-3:Usually a landing would be made on the main wheels, very rarely is a three wheel landing made. Never make a three point landing in a DC-3. The wing effectively blanks out the airflow over the rudder in the three point attitude and the fuselage is weakest at the door. A botched three point landing is a good way to damage the tailwheel structure and fuselage around the cabin door.Cool stuff.Thanks for the answers!Dan

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The only thing I do in Fu3 is adjust the mixture knob to keep the rpm's just in the green from the red while cruising. Then on approach, push it back in to ensure I have enough power to go around should I need to. I've been generally flying a C182 with Steve Hess' cockpit. Its seems to have enough of the "bells and whistles" with-out complex "flash" like the Beechjet cockpit.Jim B.

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I generally do what "feels" the best. For instance, after I have re-trimmed the aircraft, slowed down, lost altitude, lowered the undercarriage and extended the flaps.........then I control the final approach by slight variations in engine power. Whether this is the rigorously correct thing to do is irrelevant to me. Remember that we are talking about a flight SIMULATOR here. I don't have to worry about engines running out of oil, or whether the de-icers are working or not. My only mission is to make sure that I enjoy myself whilst flying, whatever happens.Chris Low,ENGLAND.

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Hi Chris,Myself, I'm a lazy sim pilot. Don't bother with trimming much. Use the auto-pilot a lot to maintain the alt and heading that the towers specify. I have been using the nav freq's as well, but generally will use the external (F5) view to get an eye on the active, all the while contacting the tower for landing. Sometimes will use 1 notch of flaps while landing. Extend them if, after dropping gears (if applicable) I see my airspeed is to high. Generally if I give myself a long enough approach, flaps as speed breaks are rarely neccessary. (well, then there's the Malibu, a very different take-off and landing experience for me).Jim B.

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Dan,Medium answer: I don't fly them to the point of realism you've described in that I don't take into account very hidden things such as the possiblity of starving the engine of lubrication. I will watch the EGT and adjust mixture accordingly, not descend too fast to minimize stress caused by rapid temperature fluctuations, not make rapid throttle changes, set appropriate prop speed for the current task, and let the engine cool down for a few minutes before shutting down especially with turbocharged engines. However, depending on where I'm flying, I can be pretty hard on a plane to get in and out of a tricky wilderness location.Short answer: As realistically as reasonable given the situation.

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Peter,Sounds like the way I fly...Here's a hint for the Mooney and other turbo-charged aircraft, from a pilot who owns a turbo'd aircraft: "I've always found the taxi to my parking spot is enough time for the turbo to wind down and cool a little. I just shut her down when I stop."Seems to work for him, and saves me time in virtual reality!Dan

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Usually first time I boot up the Sim I will try to fly realistically (threads like this help a lot in doing that!) with gradual thrust/prop changes, attention to windsocks, air procedures, occasionally checklists (esp if its a change of plane), manual engine starts, lights, (I can't do CG checks!), fuel, flight plan, weather, ..And after I crash, I reload the scenario and takeoff full throttle from the nearest taxiway ... (I think I just lost my licence).The FU3 manual says something about throttle changing from memory - not to increase/decrease too quickly.

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Sounds good, Dan. Fortunately, the sim doesn't track that stuff but it's fun to do it anyway. On a rapid descent, do you ever lean out the mixture just so the engine temperature doesn't drop drastically? Is that realistic?The best part about flight sims is that you can fly any way you want!By the way, if you're feeling mischievous, add frequent_pilot_slams to your cfg file. Those controllers can be quite a riot. :-lol

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