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larshgf

Problems reducing airspeed when descendin/approaching

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I have some problems slowing down the airspeed of my DC3 during descend/approach.When aproching an airport I descend and this phase should contains three segments: 1) Cruise Descent, 2) Initial Approach, and 3) Final Approach. (according to DC3-Airways website).(1) Cruise Descend:For instance I descend from 5500 ft to 3000 ft in order to be at 3000 ft about 10 NM from the airport. I reduce the Manifold Pressure to 20 in. and leave the props at 2050 RPM. trying to obtain a descend rate of 500 fpm and continue with an airspeed of about 140 kts.(2) Initial Approach:To slow the aircraft from about 140 kts. to 105 kts. I'm told to reduce power by setting Masinfold Pressure to 19 in., set the props back to 1700 RPM.and drop one notch of flaps. Still aiming for a descendrate of 500 fpm. (But doing this do not reduce my airspeed as planned.)(3) Final Approach:At the Outer Marker, about 5 NM from the runway threshhold the airspeed must ber reduced to 85 kts. This is done by lowering the gear and by dropping flaps to 3/4. Besides the props are pushed to high RPM.Then when you get near the field you drop full flaps. (now the airspeed is reduced to the expected values - but very late in relation to what was planned according to the profi description)My question is if these above descriped actions under usual circumstances would reduce the airspeed of the DC3? Some little trick I'm missing? Something wrong with my settings or maybee the aircrafts config file?Best RegardsLars

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>I'm told to reduce power So that we're talking the same numbers, Lars, what are you referring to for performance data? MAAM-SIM documentation or other?MarkMark "Dark Moment" BeaumontVP Fleet, DC-3 AirwaysTeam Member, MAAM-SIM[a href=http://www.swiremariners.com/cathayhk.html" target="_blank]http://www.paxship.com/maamlogo2.jpg[/a]

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Guest wji

It's not beneath me during descent to close the throttle and drop the gear to get the required reduced airspeed. Realworld pilots in GA aircraft have been know to drop the gear in cruise configuration to keep their craft shiny-side-up in severe windstorms (I've done it myself in my Mooney). It's best to do whatever is required to get the necessary result(s).P.S. As a last resort one can always put the crate into a side-slip to get down in a hurry (this maneuver is replicated quite well in FS9). Hope this helps getting your R4D rubber on the runway.

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Hi LarsThanks for clarifying that.You'll read a hundred different ideas about correct descent for the DC-3. The DCA stuff is good ... but you should certainly refer to the videos to be found in your own MAAM-SIM manual: DESCENT, APPROACH and LANDING.From my own experience of reading all the manuals, flying both the default and MAAM-SIM birds often, and listening to real world advice, this is how I do it, for a left base approach as an example:1. Descent at 300' per minute with passengers aboard (you're in an unpressurised aircraft, most companies wrote this into the ops manual), up to 500' allowable with cargo. 800' is max recommended for rapid descent. RPM remains at 2050, pull MAP back to 27-28". Avoid rapid engine cooling by reducing too quickly. Trim for 140-150 knots airspeed during descent.2. When in range (about 5 miles from airport) reduce to 25". Level out in plenty of time for pattern height in order to reduce speed to approx 135 knots when entering downwind. On downwind (2-3 miles out, no more) drop 1/4 flaps, lower landing gear, trim for 120 knots airspeed. MAP remains 25", RPM 2050.3. Turn base when intended runway threshold is at 45% to your shoulder, looking back. Trim to slow to 95-100 knots, dropping 1/2 flaps. 4. Roll out on final and drop 3/4 flaps, trim for 95 knots. Full flaps at your discretion dependent on height (you should be 500'-700' AGL at this point). Trim for 85 knots airspeed on final approach, descent rate approx 200' p.m., MAP still 25", RPM 2050. Over the fence, reduce MAP to 20", 80 knots, lift nose for final descent rate of 50-100'. Trim, trim, trim. Flare very slightly for landing, feel her down. Pull tail down gently with yoke, flaps up, go for a beer.There's lots more detail to that, of course, which the checklists will help you with, but that should get you where you need to be. Basically, do everything in plenty of time, and plan carefully. Then you should find you're flying her as you should. It's very satisfying when you get it right.Then, of course, ATC tells you to expedite descent, or fly your approach at 180 knots! Ignore them, you've been around longer than the Boeings!MarkMark "Dark Moment" BeaumontVP Fleet, DC-3 AirwaysTeam Member, MAAM-SIM[a href=http://www.swiremariners.com/cathayhk.html" target="_blank]http://www.paxship.com/maamlogo2.jpg[/a]

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Thank's Mark,It's a comfort to know that there is not ONE solution. When everything is new (like the DC3 is for me right now!) I have a tendency to look for THE solution, allthough I know that it is generally not there. Maybee its an attempt to make complicatred things more simple. There is a lot of work in the cockpit!! I will have a serious look at your schedule and the video's you mentioned.I hope its OK with a few supplementary questions:1) I guess that the most sofisticated DC3 for FS9 is the one from MAAM SIM? 2) Can you recommend other DC3's for FS9?3) I find the MAAM SIM's DC3 very fine allthough the sound in the cocktpit is a little uncomfortable, because it sounds sort of resounding or kind of pulsating. I do not know if you recognize this description? 4) Is there an alternative sound from MAAM SIM? or is it just how "the real thing" sounds?Thank you for a fine forum-- Lars

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Hi again LarsYour further questions:1. :)2. :(3,4. Hmmm ... I suppose it's just down to personal choice. I like Jan's sounds a lot, although I don't have the cockpit sound level very high ... when I flew in the real thing, I was amazed how much the sound was dampened once I was wearing a headset. To date, however, there is no alternative sound set for the MAAM-SIM aircraft that I am aware of. It is not easy to synchronise the sound levels correctly with MAP and RPM as Jan has done. Default sound sets will not work properly with the MAAM-SIM aircraft.MarkMark "Dark Moment" BeaumontVP Fleet, DC-3 AirwaysTeam Member, MAAM-SIM[a href=http://www.swiremariners.com/cathayhk.html" target="_blank]http://www.paxship.com/maamlogo2.jpg[/a]

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Guest killerwatt

I seem to remember some time ago there was a tutorial and video featuring a short flight in the DC3 taking of from Meigs Field and landing at O'Hare, which went through all the procedures including an ILS landing. If I remember right it was created by Trev Morson. I think it would be great if some kind soul would do something similar with the MAAMSIM DC3.

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