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Benjamin J

Turboprops...

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FS2004 turboprops, both the default King Air (it's a turbo prop, right?) and those addons based on the default one, really make me go mad. You advance the throttle just a little bit, and the plane just starts racing over the ground! Can anybody tell me how to proparly control these planes on the ground?

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the turboprop model in FS isn't right.there are some addons that do a much better job ... but still nothing perfect. this is a limitation of the game.for most i get better success by moving the prop-pitch v. the throttle. again, depending on the aircraft this may, or may not, be real-world practice.--

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No problem- another MS "error." The problem is MS has the condition levers set to High Idle by default. In actuality, they should always be set at Low Idle, unless of course you have put them in the Cutoff position to shut down one or both engines. In RW, the only time you'd have High Idle is temporarily under certain conditions for starting- otherwise they are always in the Low Idle position.dickbloom.

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Guest napamule

Thraini,If you plan to do miles of taxi why not get a ground handling (taxi) package and install the gauge in panel (takes 5 minutes) and get it over with. I can give it 1% throttle and taxi 12 to 15 knots (with a 3% for turning). Some people don't ever KNOW the %'age of throttle, or have a way to 'gauge' it, so they can't do taxi. That's my 2 cents worth.Chuck BNapamule

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I was under the impression that on turbo-props the condition lever is always in high idle (flight idle) when in all phases of operation except when taxiing. With a turbine engine driven prop high idle is used to reduce the engine spool-up delay when accelerating. This reduced delay is necessary when sudden power is needed for immediate climb such as in a go-around or traffic avoidance. The engine flight idle meets the minimum power needs for all flight in-air phases so you are not losing anything by using it.Ground idle is referred to frequently as ground-beta range.

No problem- another MS "error." The problem is MS has the condition levers set to High Idle by default. In actuality, they should always be set at Low Idle, unless of course you have put them in the Cutoff position to shut down one or both engines. In RW, the only time you'd have High Idle is temporarily under certain conditions for starting- otherwise they are always in the Low Idle position.dickbloom.

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We are talking about PT6A engines- any other turbo-prop I have no idea. Possibly engines with "flight idle" are different from "high idle"? I have no idea. In flying the PT6A engine I never saw a pilot, nor myself taxi with high idle. Neither when flying, nor training or PC checks, was spool up time an issue. In line with that, in normal ops, I never had the engines at idle while in the air (training or PC's excepted)- reduced power on approach yes, but not at idle. When the power levers are pulled back to idle the props go flat and you fall like a brick. It's a little difficult to run explanations here at this point because I don't know your RW experience in general, or with turbo-props or the PT6A. Did or do you actually fly these engines?db.

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My understanding is that MS did model the PT6a. I have seen documentation that the condition is left in low idle, except for starting the second engine.I think maybe the bigger issue is the power levers and how they are set up and interact with the prop. From what I've seen and read FS does not properly model performance with power levers in ground fine or beta. You can correct me please, but I thought the power levers was where "flight idle" comes in, not the condition levers.scott s..

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Let me offer this: Condition levers have 3 positions and are set at: cutoff, low idle or high idle. The power levers control engine rpm at both the low and high idle settings with high idle raising the minimum (idle) engine rpm to a higher setting (don't remember the 2 idle rpms). At lower engine rpm's the props are controled by the power levers- beta range. So I believe you are saying that, in which you are correct. I don't see that modeling in MS. However, this engine has no "flight idle" or "ground idle". BTW, I don't remember how this is modeled in MS, but for RW starting, the engine is spooled to 20% (if memory serves) and then the condition lever is moved out of the cutoff position. As I remember in FS you had to move the lever out of cutoff then hit the start switch. Otherwise, if you moved from the starter switch to the condition lever the starter would cut out. I could definitely be wrong on this FS point tho.db.

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A picture speaks a thousand words.Pictured below is the throttle quadrant of a Turbo Beaver taken at cruise. The TurBeaver is equipped with a PT6.tc_09-04-09.jpgYou can see on the far left the throttle at about half.On the far right is the standby throttle which hasn't been seen, to the best of my knowledge since FS2k2 and then it didn't work.In the middle is the condition lever clearly set at idle. As I understand it this lever is an on/off switch for the fuel.The round knob in the middle is the prop lever set to what most would recognize as fine. In my experience flying FS9 and talking to RW TurBeaver pilots, very little of what we have in FS,pertaining to turbo props, is modeled correctly.Hope this helps clear things up a bit.Oh, and to the OP, try pulling back the "condition" lever to a point just above fuel cutoff and leave it there. In FS it simply does not matter if you ever advance above that point, I don't.regards,JoePS. photo credit - Neil Aird, DHC-2.com

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Nice photo! The King Airs and B99 had the 3-position condition lever. The twin otter had a fuel lever that was either off or on. Both were PT6A's.db.

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You can see on the far left the throttle at about half.
Can't believe I actually wrote that.What I should have said is - You can see on the far left the power lever at about half.Throttles control a butterfly valve that regulates airflow into an internal combustion engine.No such critter on a turbine engine.Sorry Chris, I know, I know.regards,Joe

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Do any of you know if FS models the increase in thrust when increasing the prop pitch a bit? I'm really wondering about that, considering it doesn't slow you down at all realistically when you put the props into full low pitch.

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Ah, okay okay, so let me summarize: to proparly use the default turboprop aircraft, the condition levers, which regulate minimum prop RPM, should not be set to 100%, but, say 50% (at least not for taxi)? Then you can use the prop power lever to change currect prop RPM (like the throttle levers on a jetliner)? After I had posted this topic, I noticed these levers and was thinking that was probably it. I decided to first wait and see what would be said here though, so I didn't go and mess with these settings.Currently, it's very important I get the functioning of turboprop engines right... Is it okay what I summarized here?

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I think there is some confusion here between the RW engine and the modeling in MSFS. The MSFS modeling is not correct. I would suggest in FS you set the condition levers (King Airs or other PT6A engines) to just above the "cutoff" point and then use the power levers to handle the a/c. On the ground and takeoff the prop levers will be full forward, but reduced a little for climb and reduced a little more again for cruise. I can't give you the figures to use for reduction because I don't use that a/c in FS very often.db.

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Do any of you know if FS models the increase in thrust when increasing the prop pitch a bit? I'm really wondering about that, considering it doesn't slow you down at all realistically when you put the props into full low pitch.
ummm...guess I don't understand the question. PT6A: first, whenever I wanted to slow the a/c first thing was to reduce power (power levers). At a given power setting, if you reduce prop rpm the torque increases, if you add prop rpm the torque decreases. I never noticed this in FS.db.

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Guest jonthedoors

Don't even get me started on the TBM700 that's here on avsim!That's so hard to taxi, it's as if you move the throttle 1% forward and you're rocketing ahead at 30KTS!

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Guest jonthedoors

Wait, I mean power lever.I forgot which thread I was in; I'd better correct myself before you guys crack down on my case!

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ummm...guess I don't understand the question. PT6A: first, whenever I wanted to slow the a/c first thing was to reduce power (power levers). At a given power setting, if you reduce prop rpm the torque increases, if you add prop rpm the torque decreases. I never noticed this in FS.db.
You answered it! Sorry, when I typed it I was tired.Thanks!

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I think we are saying the same thing:Low or "ground" idle for taxiing. High or "flight" idle for all airborne phases. I think that's what I stated but perhaps confusingly and apologize. I used the words "power" lever meaning throttle or thrust control and "condition" lever for idle setting. I was not aware the PT6 flattened the props at throttle idle. I have a R/W article that stated some Saab 340B pilots on approach before the inner marker used a flat pitch with throttle at idle to use the prop as an air brake (they referred to it as "flat blading"). Their idea was to initiate final coming in "hot" and then quickly slow the aircraft with the flat prop to expedite traffic and reduce time and fuel on final. Once the airspeed was correct the thrust lever was advanced again to maintain landing airspeed and descent rate with the prop back at full (rpm) landing prop pitch. I think I was reading about REX Australia operations but I'm not sure. I thought they achieved flat pitch by adjusting the prop lever to low rpm and throttle near idle. It probably varies somewhat by aircraft.I also have a R/W book, "The Turbine Pilot's Flight Manual", 2nd Edition (out of print now but a great book) that was written for piston engine pilots to upgrade to both turbo-prop and pure jet aircraft that explains the operation of the condition lever which is defined as the idle state and in some cases fuel cut-off. My real world experience is only piloting piston engine SE including constant speed props. What is confusing for me is that times times the prop rpm lever is referred to as the condition lever.On the PC I have never needed to place the condition lever in low idle either in any stage of flight. I mostly use Mike Stone's aircraft with a customized panel for the 340B. I also note that on the PC the torque reading varies(at constant throttle) with prop rpm. Back to the OP's question:In some aircraft (including jets) taxiing is sometimes done on one engine to stay slow where ground idle and throttle idle result in too fast a taxi once the aircraft overcomes inertia and starts moving. They claim that at slow taxi speeds assymetric thrust is not a problem. (There is another technique also incorporated in some jets, can't be used in turbo-props, where instead of braking they they move the throttle or reverse thrust levers just enough to open the reverse thrust buckets keeping the engines idled - called reverse idle - to slow the aircraft if it gains too much speed. This avoids brake wear.) I don't know how well FS models this.As another reply stated I sometimes cheat on the PC by reducing the prop lever to a lower rpm position to reduce prop thrust for taxiing.

We are talking about PT6A engines- any other turbo-prop I have no idea. Possibly engines with "flight idle" are different from "high idle"? I have no idea. In flying the PT6A engine I never saw a pilot, nor myself taxi with high idle. Neither when flying, nor training or PC checks, was spool up time an issue. In line with that, in normal ops, I never had the engines at idle while in the air (training or PC's excepted)- reduced power on approach yes, but not at idle. When the power levers are pulled back to idle the props go flat and you fall like a brick. It's a little difficult to run explanations here at this point because I don't know your RW experience in general, or with turbo-props or the PT6A. Did or do you actually fly these engines?db.

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Guest belga1

Hello,

This avoids brake wear.)
On the big airliners brake wear is indeed a problem .. but the biggest problem (and this to avoid for safety matter) is the overheating of the brakes ! who is far more dangerous (at short term) than wear.Regards.bye.gifGus.

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I don't think theSAAB uses the PT6A engine- could be wrong tho.Not to beat a dead horse, but terminolgy for te PT6: Condition Lever- B99, B1900, King Air- cutoff, low idle, high idle. DHC6 (twin otter)- off, on. Prop Levers- control prop rpm except in beta range- low power setting whiick is set by power levers. Power Levers- set engine power and in beta range contol prop rpm. "flight /ground idle" is not a term used with the PT6's.Wrong nomenclature can cause confusion.db.

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