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Guest allcott

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Curious. I would like a RWP to answer this. I am flying in fsx and this refers to cessna but I suppose could apply to other ga a/c.#1 I notic in real world flying, when a small a/c takes off the flaps are set at 10 degrees. At what point are they normally retracted?#2 What altitude do you normally throttle back some? I imagine you don't fly full throttle all the time. Also, what rpm for cruising, providing weather conditions are not gusty or anything. I know it is not really essential in a sim but I would like to know if you don't mind. Thanks in advance Don

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>>#1 I notic in real world flying, when a small a/c takes off the flaps are set at 10 degrees. At what point are they normally retracted?#2 What altitude do you normally throttle back some? I imagine you don't fly full throttle all the time. Also, what rpm for cruising, providing weather conditions are not gusty or anything.<<1. I only ever use flaps for takeoff when executing special takeoffs such as a short field or soft field. I've only flown a few different a/c including the 152, 172rg, a couple of Pipers, and a Socata something or other and none of these required flaps for normal takeoff. To answer your question, you can bring the flaps up after a soft or short field takeoff generally after you have cleared any obstacle, they teach you 50ft obstacles, so once you have a positive climb and have cleared your real or assumed obstacle you can nose down let the aircraft speed up a little than bring your flaps back. 2. Depends on what you're flying, with complex aircraft, you have to pay attention to your torque readings, basically once you're clear of the runway on the climbout you can start to configure for climb. With the 172 for example, if it's a nice cool day, there's no problem with using less than full power for your climb. For the 152, I generally leave the power in until I get to the altitude I want since it is such a slow climber when the temps are high. As far as RPMs, it's not easy to get them in the red during a climb, but for cruise I believe the 152 uses about 2500 and the 172 around 2400 RPMs for cruise.Jeff

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As Jeff said-for most smaller Ga aircraft the normal takeoff setting is no flaps. Usually 10 degrees of flaps for a short field takeoff but some-like the Beech Debonair I flew, will actually recommend not using flaps even for a short field takeoff. I did some experiments when I flew this aircraft and as the Poh recommended -10 degrees of flaps did in fact decrease the takeoff performance/distance. I was surprised as all the aircraft I flew before this time always used 10 degrees for short field.I normally reduce power on a complex plane about 500 ft. Agl (25" and 2500 rpm)-but as Jeff mentioned--for many simpler non complex planes you can leave it all the way in. The engine looses power as you climb due to the thinner air-(about 1" inch of manifold pressure per 1000 ft.) so the reduction will happen automatically-if you are not over the redline line you should be ok-if right at it I would reduce at 500 agl. Of course then you have to remember to increase to maintain your power setting as you climb and loose power-eventually you will be back to full throttle depending on the altitude/density altitude.http://mywebpages.comcast.net/geofa/pages/rxp-pilot.jpg

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I realize now, thinking about it, that the airfield that I have watched planes takeoff probably would be considered a short field. Actually from what you guys said, it sounds like a lot of conditions dictate whether flaps are used or not. Things like length of runway, strength of wind, and heavy or light air etc. Thanks for the comeback.In fsx, my home airport has two runways- 33/15 and 1/19. The 33 is the long one and seems like the other one should be used by g/a, but I have never gotten clearance to 1/19 even though I have changed the wind at different angles. Guess it is not programmed to use that runway.Don

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>I realize now, thinking about it, that the airfield that I>have watched planes takeoff probably would be considered a>short field. Actually from what you guys said, it sounds like>a lot of conditions dictate whether flaps are used or not. >Things like length of runway, strength of wind, and heavy or>light air etc. Thanks for the comeback.>In fsx, my home airport has two runways- 33/15 and 1/19. The>33 is the long one and seems like the other one should be used>by g/a, but I have never gotten clearance to 1/19 even though>I have changed the wind at different angles. Guess it is not>programmed to use that runway.>>Don>Increasingly, environmental factors are also taken into consideration - full throttle low over the neighbouring houses is frowned upon as bad relations, even if the airfield has been there for fifty years, and the houses five. :) It is very, very aircraft specific, but on the 172 I generally won't use flaps on tarmac, or on a long grass field. 172's are not possessed of an abundance of power for their weight, so a clean climb allows more IAS, sooner. For all aircraft IAS is life.But a `flapped` 172 will definitely leave the ground sooner, so if the grass is soft or the field short you gain more by flying sooner, staying in ground effect to start with and using the flaps until you get to a few hundred feet. Climb power on a 172 is full throttle most of the time, so the choice of flaps is really about getting off the ground and the GROUND speed - for a given point on the ground you can reach a higher altitude at the same climb rate if the angle of climb is greater. If you think about some basic math: At a ground speed of 60 knots you are travelling across the ground at 1 mile per minute. At 120 knots its 2 miles in the same minute. If you climb at 500 fpm and are going to overfly a house that's two miles downrange from the takeoff point, then at 60 knots you will overfly at 1,000 feet. At 120, just 500. Which makes you the better `neighbour`? Another reason for using flaps is if the field procedure calls for a turn immediately after take-off, when you need the additional lift and stall margin.Allcott

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